Environmental Analysis: Uncovering Earth’s Pollutants

SPONSORED BY Environmental Analysis: Uncovering Earth’s Pollutants Inside the Evolving Landscape of PFAS Regulation New Methods To Combat Environmental Pollutants Microplastics: How Do They Spread? Credit: iStock 2 TECHNOLOGYNETWORKS.COM Contents Digging Deep: Emerging Contaminants in Soil 5 Inside the Evolving Landscape of PFAS Regulation 8 Testing London’s Water for PFAS 12 Newly Discovered Fungus Capable of Degrading Plastic 14 New Methods To Combat Environmental Pollutants 17 Microplastics: How Do They Spread? 19 Water Analysis: A Pollution Solution? 22 3 TECHNOLOGYNETWORKS.COM Environmental Analysis Foreword Welcome to “Environmental Analysis: Uncovering Earth’s Pollutants,” an insightful exploration into the growing challenges and innovative solutions in the realm of environmental pollution. In this eBook, we delve into the multifaceted world of contaminants, from soil pollutants and PFAS (Per- and Polyfluoroalkyl Substances) in water to the ubiquitous microplastics threatening both terrestrial and aquatic ecosystems. We also explore the discovery of a fungus capable of degrading polyethylene, offering a glimpse of hope in our fight against plastic pollution, and examine the evolving landscape of PFAS regulation and the innovative methods being developed to detect and combat these persistent chemicals in our water supplies. By understanding the complex interactions between pollutants and ecosystems, we can develop more effective strategies to protect our environment and ensure a sustainable future for generations to come. Join us as we uncover the hidden threats to our planet and the pioneering efforts to combat them. Copyright © 2024 PerkinElmer U.S. LLC. 119752 All rights reserved. PerkinElmer® is a registered trademark of PerkinElmer U.S.LLC. All other trademarks are the property of their respective owners. PFAS ANALYSIS INTO CONFIDENCE COMPLEXITY For regulatory and contract testing labs performing PFAS analysis, we understand that staying compliant with evolving testing requirements while minimizing instrument downtime and boosting efficiency can be challenging. That’s why our LC/MS PFAS testing solutions support lab efficiencies with increased uptime from reduced system contamination, even when dealing with complex matrices. Our Application team offers end-to-end support, providing scalable, validated method implementation to help labs adapt to changing regulations. Partner with PerkinElmer today to build future-proof PFAS analysis workflows in your lab. Robust, Reliable and Compliant PFAS Testing Solutions Click here to learn more www.perkinelmer.com/pfas 5 TECHNOLOGYNETWORKS.COM Credit: iStock. You might be forgiven for thinking soil is just dirt beneath our feet. Certainly, this writer vastly misjudged its importance to life as we know it. It’s becoming increasingly obvious that soil could be the unsung hero of our planet, quietly working behind the scenes to keep everything in balance. Sure, it’s crucial for growing our food, but its role goes way beyond that. Think of soil as one of Earth’s most important life support systems. In addition to nurturing crops, soil does some heavy lifting in fighting climate change. It’s like nature’s sponge, soaking up carbon and helping to regulate our planet’s temperature – it’s a natural filter, purifying the water and air we depend on for our very existence. And let’s not forget about the bustling community of insects that call soil home. They’re the ultimate recyclers, breaking down dead plants and organic matter, and keeping the whole ecosystem ticking. Even in our cities, soil plays a vital role – handling heavy rain, absorbing pollutants and even playing a part in mitigating the urban heat island effect. It’s the foundation for our urban gardens, parks and playgrounds – the green spaces that make life in cities that little bit more bearable and greener. However, beneath the earth’s surface, there is a whole hidden world of growing threats to soil from emerging contaminants. These contaminants, ranging from harmful collations of heavy metals and pesticide derivatives to pharmaceutical residues, biological pathogens and plastic waste, hold an alarming power when left unchecked, posing significant threats to environmental, animal and human wellbeing. Human practices such as polluting industrial activities, agriculture and urbanization all contribute to ongoing environmental pollution. Their impact on soil not only compromises health, fertility and biodiversity but also has far-reaching implications for food safety and water quality. Biological pathogens, including bacteria, viruses and parasites, introduced through improper waste disposal and agricultural runoff, are another source of worry. These can lead to the spread of many diseases and require thorough screening to ensure they do not compromise public health. Moreover, the relatively recent and pervasive presence of plastic waste, composed of non-biodegradable materials, further exacerbates environmental degradation. Microplastics and nanoplastics infiltrate soil and water systems, posing threats to both terrestrial and aquatic ecosystems by entering the food chain ‒ endangering human health from the presence of pathogens carried on their surface. Addressing the multifaceted nature of contaminants is crucial for mitigating their detrimental effects and safeguarding the integrity of our environment and wellbeing now and for our future generations. “Understanding what soil is comprised of can be extremely challenging,” said Dr. David Hackett, chair of the British Standards Institution’s AW/20 Soils Other Growing Media and Turf Committee. He elaborated on the implications of emerging contaminants in soil ecosystems, shedding light on their potential impacts and challenges in detection. “It’s one thing to identify its Digging Deep: Emerging Contaminants in Soil Nicholas Gaunt, PhD Environmental Analysis 6 TECHNOLOGYNETWORKS.COM Environmental Analysis components, but it’s a whole new problem to comprehend their environmental impact. Organic chemicals, for instance, may break down into other harmful substances, making it crucial to assess their effects on the environment.” So, what challenges do we face in addressing the longterm impacts of contaminants on soil health? And how can we develop effective solutions? “With the rise of things like micro-, and now, nanoplastics being a relatively recent phenomenon, we’re still learning about their long-term impacts after decades of use,” Hackett told Technology Networks. The difficulty lies in understanding the significance of soil contaminants but also in determining effective solutions, especially when they’ve become ubiquitous. The ultimate solution is stopping the production of contaminants. But addressing historic problems like “forever chemicals” will require a deeper understanding and robust approaches.” Upon being questioned on the importance of examining the chemical contaminants themselves, Dr. Hackett continued, “We need to consider not just the chemical itself but also how it finds its way back to potentially impact human health. While we can observe its impact on the environment to some extent, understanding its route back to human consumption is crucial. The efficiency and likelihood of contaminants reaching humans are key considerations. This journey from soil to human consumption is dynamic and constantly changing, making it imperative to monitor and understand.” Analytical conundrums Understanding this comprehensive microbiome ecosystem cycle is crucial in safeguarding, not only the health of the animals and crops that we consume but also the health of wild species; there is a collective expert recognition that a diverse and resilient soil microbiome is essential for ecosystem health. So how can soil be monitored and studied? It’s a task that’s challenged scientists for decades. The complex nature of soil matrices, coupled with the diverse range of contaminants, makes detection and quantification tremendously complex. Traditional analytical methods often fall short in accurately assessing contaminant levels, necessitating the development of cutting-edge techniques. “Current techniques for analyzing complex matrices like soil must meet rigorous standards before being utilized, especially in legal proceedings where transparency and reliability are paramount,” said Professor Lorna Dawson, head of the Centre for Forensic Soil Science at the James Hutton Institute. “Methodologies must undergo thorough testing, publication, and peer review to ensure their validity, credibility, accuracy and reliability, with rare exceptions only being made for intelligence purposes.” “While cutting-edge analytical techniques, such as volatile organic compound analysis using gas chromatography-mass spectrometry, show promise in identifying suites of organic compounds to identify sources of decomposition, their reliability in court settings remains unproven,” Dawson warned. Future directions Efforts to remediate soil contamination issues are underway, with many countries across Europe making progress on soil remediation measures to more sustainable and regulated models for agricultural practices. These practices aim to provide fairness for farmers, while achieving high sustainability, meeting societal expectations and contributing to climate neutrality. Looking ahead, innovation in soil analysis holds promise for enhancing our understanding of soil ecosystems and mitigating contamination risks. Innovative solutions such as customized soils and collaborative research endeavors will be instrumental in addressing the current and emerging challenges in both soil management and overall environmental conservation. “We’re witnessing a shift towards understanding the nature of new contaminants and their impacts.” noted Dr. Hackett when asked about the future of soils “The future lies in developing tools to identify these contaminants and determining their effects, whether harmful or not, to devise appropriate treatment methods. Additionally, soil analysis is expanding beyond agriculture to support urban life, such as in the cultivation of street trees and green roofs. From contaminated soil to the physical and chemical properties, comprehensive analysis is essential. Developing analytical tools and resources to assess soil quality and guide its utilization is key to the future of soil analysis.” Professor Dawson spoke on the current analytical limitations and what the future looks like from a technological point of view. “It all hinges on the seamless integration of these technologies, enabling precise decision-making in the field,” she said. “I’d love to imagine a future where physical, chemical and biological sensors work in tandem, allowing for comprehensive soil analysis at a glance. While this vision may seem ambitious, with continued innovation and collaboration, we can pave the way for a more sustainable and resilient future based on the best available evidence.” 7 TECHNOLOGYNETWORKS.COM Environmental Analysis Soil analysis: Earth’s silent hero? On reflection, it’s clear that soil analysis is very swiftly emerging as a silent hero in safeguarding environmental health and sustainability. In 2024 and beyond, as we continue to navigate the complexities of soil management and environmental conservation, advocacy for continued collaboration and research efforts is paramount. It should remain a top priority to develop and implement rigorous standards and innovative solutions to address soil contamination issues effectively. Collaboration among scientists, policymakers and stakeholders is essential to ensure our remaining soil is protected. And, by investing in research, technology and sustainable practices, we can ensure a resilient and healthy soil ecosystem for the wellbeing of all life on Earth. About the interviewees: Dr. David Hackett BSc (Hons) MLD PhD MCIEEM CEnv, co-founder of Biora, is a distinguished expert in plantsoil relations and landscape architecture, boasting over three decades of experience in brownfield regeneration. He currently chairs the British Standards Institution’s AW/20 Soils, Other Growing Media and Turf Committee, where he leads efforts to establish industry standards. Dr. Hackett’s visionary approach and unwavering commitment to sustainability have made him a prominent figure in the field, driving transformative change in landscape design and environmental conservation. Prof. Lorna Dawson, CBE, is head of the Centre for Forensic Soil Science at the James Hutton Institute in Aberdeen and an Honorary Professor at RGU, Aberdeen. She is a registered expert with the National Crime Agency and has worked on over 100 forensic cases, presenting evidence in court for over 20 of these. She holds diplomas in civil and criminal law (Cardiff University, 2011, 2012, 2017 and University of Aberdeen, 2021) She is a Commissioner with the Food, Farming and Countryside (FFCC) and authored the RSA Scotland FFCC report (2019) and is co-chair of the devolved Scotland inquiry. She recently served on the Scottish Government Arable Climate Change Advisory Group (ACCG) and is on the scientific advisory panel for the Scottish Government’s Agriculture Reform Implementation Oversight Board (ARIOB). She is treasurer of the IUGS Initiative on Forensic Geology (IFG) and Chair of the Geological Society Forensic Geology Group (FGG) and an affiliate member of the Organisation of Scientific Area Committees (OSAC) for Forensic Science, USA. She was awarded a CBE in the late Queen’s birthday honors list, June 2018, for services to soil and forensic science and was made a Fellow of the Royal Society of Edinburgh (FRSE) in 2019 and awarded Soil Forensic Expert Witness of the Year in the Corporate INTL 2021 Global Awards. 8 TECHNOLOGYNETWORKS.COM Environmental Analysis Credit: iStock Inside the Evolving Landscape of PFAS Regulation Alexander Beadle Since their invention in the mid-20th century, perfluoroalkyl and polyfluoroalkyl substances, or PFAS, were quickly adopted as key components of firefighting foams, non-stick coatings for cookware and other water and oil-resistant materials.1 However, in subsequent years, the scientific community would discover that these compounds did not readily degrade in the environment once released, raising some troubling environmental concerns. In response, a number of jurisdictions would go on to introduce policies aimed at reducing the use of PFAS.2 Bodies such as the European Union have also recently proposed and adopted limits on the levels of PFAS that are allowable in drinking water.3 Just like the regulatory landscape for these compounds, the scientific understanding around PFAS is still evolving. While studies have suggested that PFAS can present health risks to humans,1 the effects of long-term exposure are still not fully understood, especially in more vulnerable populations. There is also demand for improved PFAS testing method development and further study of the compounds that are now being used in PFAS’ stead, to ensure that these do not present similar risks. Together, these studies continue to inform the evolving landscape of PFAS regulation as national and international governing bodies look to safeguard the environment and public health. What are PFAS and what risks do they pose? PFAS are a class of fluorine-containing polymers with remarkably unique physical and chemical properties. Their water and oil repellency, temperature resistance and ability to reduce friction resulted in them being used extensively by the textile and cookware industries, with firefighting forces also taking advantage of their flame-retardant properties to create more effective firefighting foams. However, the same extreme chemical stability that was key to their utility also results in these compounds being highly mobile, persistent and bioaccumulative environmental contaminants.4 In addition, these compounds can be difficult for traditional remediation technologies to deal with.5 The extreme longevity of these compounds in the environment has even earned them the nickname the “forever chemicals”. “PFAS are everywhere, and nearly everyone currently has some measurable amount of PFAS in their blood,” said Dr. Anne P. Starling, an assistant professor of epidemiology at the University of North Carolina at Chapel Hill (UNC) Gillings School of Global Public Health. Starling also serves as a coprincipal investigator at the Agency for Toxic Substances and Disease Registry’s (ATSDR) Colorado site for a national study of the health effects of PFAS in drinking water. “Older consumer products containing PFAS can deteriorate and be ingested as dust in households and workplaces. People continue to be exposed to PFAS through drinking water in many parts of the US, and even 9 TECHNOLOGYNETWORKS.COM Environmental Analysis those without PFAS in their drinking water are regularly ingesting small amounts of PFAS through food and dust,” she explained. PFAS have essentially become ubiquitous, and have even been found in samples from remote regions of the Antarctic.6 Yet, despite our continued exposure to these compounds, researchers are only now beginning to unravel the health implications presented by PFAS. “Much of what we know about the health risks of PFAS exposure in humans is based on studies of highly exposed workers, including firefighters exposed to PFAS in aqueous film-forming foams and workers in factories producing fluorochemicals including PFAS,” Starling explained. “These studies have consistently shown associations between PFAS exposure and higher cholesterol in the blood as well as higher levels of enzymes that may indicate damage to the liver. Some PFAS are also suspected to increase the risk of kidney cancer and testicular cancer.” While restrictions on the manufacture of PFAS products mean that this kind of high-volume exposure to the compounds is a rare occurrence these days, researchers are still keen to examine the health impacts of longterm exposure to lower levels of PFAS contamination, particularly among more vulnerable demographics. “Some PFAS have been associated with a wide range of serious health harms, from cancer to more severe COVID-19 outcomes. Children are especially vulnerable not only because their organs are still developing, but also because they often have higher exposures,” said Rebecca Fuoco, MPH, director of science communications at the Green Science Policy Institute. In addition to maintaining the PFAS Data Hub, the Green Science Policy Institute is in active collaboration with scientists and politicians to improve regulations and research efforts relating to PFAS. “Per pound of body weight, children eat more food, drink more water and breathe more air—all of which can be contaminated with PFAS,” Fuoco continued. “Infants and toddlers may have even higher exposure due to crawling and hand-to-mouth behaviors. Exposure to certain PFAS during childhood or in utero has been linked to reduced antibody response to certain vaccines and infections, obesity, higher cholesterol and more.” PFAS regulation around the world In light of the potential dangers presented by PFAS, many national governments and international institutions have moved to introduce regulatory policies and guidelines aimed at stemming the tide of PFAS production and protecting the public from exposure.2 Arguably the most prominent of these policies is the Stockholm Convention, a global treaty signed by 152 countries committing to protect human health and the environment from what it dubs “persistent organic pollutants”, or POPs.7 Signatories to the Convention are required to either completely prohibit or significantly reduce the manufacture, import and export of POPs. Currently, the Convention recognizes three PFAS — perfluorooctanoate (PFOA), perfluorooctane sulfonate (PFOS) and perfluorohexane sulfonic acid (PFHxS) — as POPs,8 with long-chain PFAS as a collective group also under consideration for future inclusion. “PFOA and PFOS in particular are considered “legacy pollutants”, because their use has been restricted and production has ceased in many industrialized countries,” Starling explained. “However, PFOA and PFOS, along with other long-chain “legacy” PFAS and newer, shortchain PFAS used as replacements, are still widely detected in blood samples from adults and children in the general public. This is likely due to the extreme persistence of these chemicals in the body and in the environment.” Outside of the Stockholm Convention, there are a number of different restrictions currently regulating the use and production of PFAS9 in the EU. The European Chemicals Agency (ECHA) restricts the manufacture and use of several individual PFAS under the registration, evaluation, authorisation and restriction of chemicals (REACH) regulation. In addition, authorities in Denmark, Germany, the Netherlands, Norway and Sweden recently submitted a joint proposal to the ECHA that seeks to ban all PFAS compounds as a group, which will be consulted on throughout 2023.10 Relevant EU regulation on PFAS also includes the Drinking Water Directive, which includes limits for total PFAS set at 0.5 μg/L, and the sum of 20 PFAS deemed to be of most concern at 0.1 μg/L. It also requires the European Commission to establish new technical guidelines on standard methods of analysis for PFAS monitoring in water.11 In the United States (US), the Environmental Protection Agency recently published a new PFAS strategic roadmap and national testing strategy that will require manufacturers working with PFAS to report toxicity testing data to the Agency.12 “PFAS have contaminated freshwater fish in rivers and lakes throughout the US,” Starling explained. “Many drinking water sources have been contaminated with PFAS, and the US currently has no enforceable maximum contaminant limit for the amount of PFAS present in treated drinking water.” 10 TECHNOLOGYNETWORKS.COM Environmental Analysis Despite the current lack of enforceable federal guidance on the issue, several US states have now begun to adopt the non-enforceable EPA Lifetime Drinking Water Health Advisory Level of 70 ppt for PFOS and PFOA, or have adopted their own limits of similar values.13 The future for PFAS testing It is clear that this evolving regulatory environment is likely to have a significant impact on testing. For example, in the absence of federal regulations, nine US states have adopted drinking water standards or guidance values set at levels lower than the EPA advisory levels.2 Such stringent guidelines bring about a new need for analytical testing methods with much lower limits of quantification. As exemplified by the Drinking Water Directive and subsequent commitments from the European Commission, developing methods that are capable of detecting and quantifying a wide range of different PFAS compounds at once is also a priority. Also advocating for improved non-targeted methods are those who believe that PFAS would be better managed as a broad class of compounds. With less than one percent of known PFAS having been tested for toxicity,14 there is concern that testing procedures that only deal with one compound at a time may delay efforts to protect health and the environment. “Only a small fraction of the thousands of PFAS have been tested for toxicity, but we know that all PFAS are either extremely persistent in the environment or break down into extremely persistent PFAS,” Fuoco said. “Additionally, some newer PFAS first claimed to be safe were later determined to be harmful to our health. To stem further irreversible damage, we need to eliminate all non-essential uses of this problematic class as soon as possible.” In line with regulatory efforts that aim to limit PFAS production and stem the flow of PFAS contaminants into the environment, there is also a desire for increased environmental monitoring and surveillance using techniques that are able to detect these compounds in environmental samples quickly. This has been accompanied by a wave of promising development efforts towards creating low-cost PFAS-detecting sensors that can be deployed in situ and provide rapid readouts for assessment.15 As PFAS testing efforts and health studies continue to highlight the dangers of PFAS contamination, legislators are using this data to introduce new policies that dictate when and how contamination is screened for and handled. In turn, this evolving regulatory landscape is helping to drive the development of new detection and analysis methods that can be deployed where concerns are raised, furthering the array of tools and technologies available to help make our environment safe for all. High-content screening is an imaging method that combines the automated recording of multicolor fluorescence imaging and high-throughput quantitative data analysis. The approach helps extract spatial and temporal information about target activities within cells. It yields information that allows better lead optimization before in vivo testing. The way forward The pharmaceutical industry’s commitment to advancing drug discovery has led to several innovations and has transformed the HTS sector. Remarkable advances in analytical technology and laboratory automation tools have increased the efficiency of HTS workflows with minimal manual intervention and less material required. However, the increased data generated warrants more efficient and quicker data management and modeling tools such as machine learning and first-principles modeling. About the interviewees: Dr. Anne P. Starling is an assistant professor of epidemiology at the University of North Carolina at Chapel Hill Gillings School of Global Public Health. Starling also serves as a co-principal investigator at the Agency for Toxic Substances and Disease Registry’s Colorado site for a national study of the health effects of PFAS in drinking water. Rebecca Fuoco is the director of science communications at the Green Science Policy Institute. She previously worked as a communications strategist for nonprofit organizations and academic research centers in the health and environmental fields and holds a master’s of public health degree from UC Berkeley, where she was a Center for Health Leadership Fellow. References 1. What are PFAS? Agency for Toxic Substances and Disease Registry. https://www.atsdr.cdc.gov/pfas/ health-effects/overview.html. Published June 24, 2020. Accessed March 2023. 2. Brennan NM, Evans AT, Fritz MK, Peak SA, von Holst HE. Trends in the regulation of per- and polyfluoroalkyl substances (PFAS): A scoping review. Int. J. Environ. Res. Public Health. 2021;18(20):10900. doi:10.3390/ijerph182010900 3. Perfluoroalkyl chemicals (PFAS). European Chemicals Agency. https://echa.europa.eu/hot-topics/ perfluoroalkyl-chemicals-pfas. Accessed March 2023. 4. Interstate Technology Regulatory Council. History and use of per- and polyfluoroalkyl substances (PFAS). https://pfas-1.itrcweb.org/fact_sheets_page/ PFAS_Fact_Sheet_History_and_Use_April2020.pdf. Published April 2020. Accessed March 2023. 11 TECHNOLOGYNETWORKS.COM Environmental Analysis 5. Interstate Technology Regulatory Council. Treatment Technologies. https://pfas-1.itrcweb.org/12- treatment-technologies/. Updated August 2021. Accessed March 2023. 6. Microplastics and persistent fluorinated chemicals in the Antarctic. Greenpeace. https://www. greenpeace.org/static/planet4-internationalstateless/ 2018/06/4f99ea57-microplastic-antarcticreport- final.pdf. Published 2018. Accessed March 2023. 7. Overview. UN Environment Programme Stockholm Convention. http://www.pops.int/TheConvention/ Overview/tabid/3351/Default.aspx. Published 2013. Accessed March 2023. 8. Information on the 16 chemicals added to the Stockholm Convention. UN Environment Programme Stockholm Convention. http://www.pops.int/ TheConvention/ThePOPs/TheNewPOPs/tabid/2511/ Default.aspx. Accessed March 2023. 9. Portal on Per and Poly Fluorinated Chemicals. Organisation for Economic Co-operation and Development (OECD). https://www.oecd.org/ chemicalsafety/portal-perfluorinated-chemicals/ countryinformation/european-union.htm. Accessed March 2023. 10. ECHA publishes PFAS restriction proposal. European Chemicals Agency. https://echa.europa.eu/-/echapublishes- pfas-restriction-proposal. Published February 2023. Accessed March 2023. 11. Directive (EU)2020/2184 of the European Parliament and of the Council of 16 December 2020 on the quality of water intended for human consumption (recast). L 435/1. https://eur-lex.europa.eu/legal-content/ EN/TXT/PDF/?uri=CELEX:32020L2184&from=EN. Accessed March 2023. 12. Key EPA Actions to Address PFAS. US Environmental Protection Agency. Published March 13, 2018. https:// www.epa.gov/pfas/key-epa-actions-address-pfas. Accessed March 2023. # 13. Lifetime Drinking Water Health Advisories for Four Perfluoroalkyl Substances. Environmental Protection Agency. FRL 9855- 01-OW. https://www.federalregister.gov/ documents/2022/06/21/2022-13158/lifetimedrinking- water-health-advisories-for-fourperfluoroalkyl- substances. Accessed March 2023. 14. Findings and Recommendations of the North Carolina Per- And Polyfluoroalkyl Substances Testing Network: Final Report to the North Carolina General Assembly. NC PFAST Testing Network. https://ncpfastnetwork. com/wp-content/uploads/sites/18487/2021/04/NCPFAST- Network-Final-Report_revised_30Apr2021. pdf. Published April 2021. Accessed March 2023. 15. Kwiatkowski CF, Andrews DQ, Birnbaum LS, et al. Scientific basis for managing PFAS as a chemical class. Environ. Sci. Technol. Lett. 2020;7(8):532-543. doi:10.1021/acs.estlett.0c00255 16. Rodriguez KL, Hwang JH, Esfahani AR, Sadmani AHMA, Lee WH. Recent developments of PFASdetecting sensors and future direction: A review. Micromachines. 2020;11(7):667. doi:10.3390/ mi11070667 12 TECHNOLOGYNETWORKS.COM Environmental Analysis Credit: iStock Testing London’s Water for PFAS Leo Bear-McGuinness British water is in need of some good publicity. The country’s water companies have been mired in controversy in recent years following reports of mismanagement, widespread leaking pipes, sewagesaturated seas and record fines. In a recent survey, only 34% of respondents trusted their local water company to prevent sewage from entering rivers and seas. So, the last thing these companies would want right now is a trending story about another dangerous contaminant in the country’s water systems. But such a headline may just be around the corner… London trawling: looking for forever chemicals in the Thames Per-and polyfluoroalkyl substances (PFAS) are a growing concern around the world. The group of surfactants were first mass produced in the mid-20th century to waterproof consumer products like pans, paints and packaging. They’re now known as “forever chemicals” because they have an almost-unbreakable highlyfluorinated alkyl chain backbone that makes them extremely chemically stable and difficult to degrade naturally. This robustness has helped the chemicals reach as far the Arctic and the base camp of Mount Everest. So it’s no surprise they’re in British rivers, too. What may be more shocking is the level of PFAS that might persist in the nation’s drinking water, particularly as a recent wave of research has linked the compounds to health concerns like cancer and low birth weights. A recent report from the Royal Society of Chemistry found that more than a third of tested water courses in England and Wales contained medium- or high-risk levels of PFAS. The river Thames in London was one of the most polluted sites the team sampled; the capital’s waterway contained a combined PFAS concentration level of 4,931.1 nanograms per liter (ng/l) – nearly 50 times the Royal Society’s proposed limit (100 ng/l) of all forever chemicals in drinking water. So, the pertinent question is: how many of these PFAS compounds are making their way through the river’s filtration network and into London’s drinking water? To work that out, researchers would need to gather tap water samples from across the city, which is exactly what one team is about to do. “We want to quantify how much PFAS is coming out of the taps in people’s homes,” said Dr. Alexandra Richardson, a researcher at Imperial College London’s School of Public Health. Richardson is heading up the university’s Investigating the Toxicological Assessment of PFAS (ITAPS) project, which is partly funded by the Royal Society of Chemistry. 13 TECHNOLOGYNETWORKS.COM Environmental Analysis “There are guidelines for what PFAS levels are suitable once it leaves the drinking water treatment plant, but there’s a lot of piping between the treatment plants and our kitchen taps,” said Richardson. “In the US, that there are quite a few studies looking at what’s coming out the taps in the various states in the USA, but nothing really in the UK. So that’s what this project is about.” To gather the required data, Richardson and her colleagues have already recruited 40 participants, and hope to enlist more from across the city after the Easter break. “From an experimental and scientific standpoint, a scatter [of data] across London is what we’re trying to achieve – good representation from almost every from every London borough,” said Richardson. “Because we genuinely do not know if the PFAS concentrations vary across the city at all, or one region, or if a region with old infrastructure is better or worse affected than a newer build area. We genuinely don’t know.” More PFAS, more research If the team do end up detecting high levels of PFAS in one particular area, they’ve vowed to notify all relevant participants. “We want to give back to the community in some ways,” Richardson continues. “We are planning on giving them the concentrations of PFAS in line with the current drinking water spectra guidelines, which I’ve hoped would be below the lowest tier. If a house does trigger a concern, then we will investigate that further. But it’s a balance, as we don’t want to fear monger.” This balance between safety and excessive scrutiny is something that, according to Richardson, hasn’t always been struck when it comes to recent PFAS regulation, particularly in the US. “I think the US has gone a bit overboard in some ways with it,” she said. “PFAS and PFOA [perfluorooctanoic acid] are nasty compounds. There are definitely indications there might be cancer risk caused by them. But asking labs to routinely test down to four PPT [parts per trillion], it’s a very big ask, analytically.” In 2022, the US Environmental Protection Agency (EPA) issued its interim PFOA and perfluorooctanesulfonic acid [PFOS] limit of 4 ng/l for single samples. In comparison, the European Union’s collective limit for 20 PFAS chemicals is 100 ng/l. While there are no firm limits for PFAS in England and Wales, there are “wholesomeness” guidelines to keep 47 individual PFAS compounds to 100 ng/l. While the Royal Society of Chemistry isn’t as ardent as the EPA, it has proposed more stringent PFAS limits for the UK (100 ng/l for all collective compounds) to bring the country’s regulations in line with the continent. In its report last year, the society also called on the UK government to enforce stricter limits on PFAS industrial discharge and ensure that many hundreds of sources of PFAS are captured and documented in a national lab for record-keeping. In principle, Richardson agrees that more PFAS research can only be a good thing for public health policies. “I hope that research along this route will continue,” she said. “It doesn’t necessarily have to be the same model as the ITAP study. It’s like the early days of understanding the health effects of air pollution. We know these things are in the environment. We know they can cause effects. But we don’t know the human dose at the moment. Because we don’t know how much we ingest in food or tap water. Therefore, it’s very hard to put a toxicology value on it and to determine effect. So, I definitely hope that PFAS research into human health exposures and human health effects will definitely continue because I do think it’s something that is important.” Richardson hopes the ITAP study will have produced its first round of results by the end of this year. Dr. Alexander Richardson was speaking to Leo Bear- McGuinness, Science Writer for Technology Networks. About the interviewee: Dr. Alexander Richardson is a research associate within the Epidemiology and Biostatistics (EBS) and Emerging Chemical Contaminants (ECC) groups at Imperial College London. 14 TECHNOLOGYNETWORKS.COM Environmental Analysis Credit: iStock. Newly Discovered Fungus Capable of Degrading Plastic Kate Robinson Humans produce over 380 million tons of plastic every year, and this number is expected to have tripled by 2060. Much of this waste appears in our oceans, and the most abundant type, polyethylene, can be found floating in surface waters and even resting on the seafloor. In a paper published in Science of The Total Environment, researchers from the Royal Netherlands Institute for Sea Research (NIOZ) reported on the discovery of a fungus capable of breaking down polyethylene particles. The researchers collected plastic litter from the hotspots of plastic pollution in the North Pacific Ocean, leading to the discovery of the degrader, Parengyodontium album. Technology Networks spoke to Dr. Annika Vaksmaa, the lead author of the paper, to learn more about how plastic impacts marine life, the discovery of plastic-degrading microbes, and the importance of plastic degraders Q: How does plastic litter in the ocean impact marine life? A: Plastic litter in the ocean has severe and far-reaching effects on marine life. Among many impacts of this pollution, one of the best known is the impact on marine animals that mistake plastic debris for food. When ingested, this plastic can cause malnutrition, blockages and even death. Additionally, other impacts may be due to the toxic additives plastics often contain or compounds absorbed from the water. Additionally, fish, birds and turtles can become entangled in plastic items such as fishing nets and plastic bags, leading to injuries, impaired movement and sometimes drowning or suffocation. Plastic also contributes to habitat destruction. For example, coral reefs can be smothered by plastic debris, blocking sunlight and hindering their growth, while plastic accumulating on the seabed disrupts the habitats of bottomdwelling organisms. And counteractively, while it destroys natural habitats, it forms others. This is especially apparent in areas such as the Pacific garbage patch, where organisms that should not be far out from the coast have found new surfaces to attach to and live on. When plastics are transported in aquatic ecosystems, they can also carry along many species and facilitate the transport of invasive species and pathogens that disrupt local ecosystems. In addition, as larger plastic items break down, they form microplastics, which are ingested by a wide range of smaller marine organisms. While some studies into the effects of micro and nanoplastics do exist, far more research is needed. Q: What inspired your attempt to uncover plastic-degrading microbes? A: I have always been fascinated by environmental problems such as climate change, which was the subject of my PhD. During this time, I investigated microbes that can oxidize methane. Now, I am focusing more on plastic pollution in the ocean. 15 TECHNOLOGYNETWORKS.COM Environmental Analysis I am particularly intrigued by the use of microbes to mitigate environmental issues. The resilience and adaptability of microbes offer a unique and powerful tool for addressing environmental challenges. Discovering and harnessing plastic-degrading microbes can improve the understanding of what happens in nature: which microbes live on plastic, and which can then potentially break it down. In the future, microbes may offer a solution to reducing plastic waste Q: How does P. album degrade plastic? A: We have now seen that P. album is able to break plastic down, but uncovering how that process happens and which fungal enzymes are involved is another step in this process. It definitely will be worthwhile to identify the molecular mechanisms as this will provide another method of seeking out plastic degraders. If we know the enzymes responsible, we can see which other microbes and their genomes contain these, and from there, we could test if they do break down the plastics as well. Q: What methods did you use to study the degradation process? A: In this study, we used isotopically labeled polyethylene. This is one of the most abundant polymers produced and discarded, so large amounts of it are present in our oceans. Studying the degradation process, which is known to be extremely slow, using these “tagged” plastics enables us to monitor the production of degradation products such as CO2 with very sensitive detection methods. This allows us to measure plastic degradation in less than a week. In nature, plastics take decades to break down and many require even longer. We used nanoscale mass spectrometry for high-resolution imaging and precise chemical analysis. Such methods are crucial for understanding the intricate processes involved in plastic degradation at a very detailed level. However, our results showed that the 13C tag from plastic is mainly found in CO2 and to a lesser extent in biomass, indicating that P. album does not use it for growth. We also used scanning electron microscopy (SEM) which allowed us to see detailed surface structures and the morphology of biomass at the microscale. This is crucial for understanding how microorganisms and biofilms attach to and interact with surfaces, including plastics. Q: How important is it to discover other plastic degraders? A: Finding other plastic degraders is very important. We now know quite a bit about bacteria and fungi degrading plastics in the terrestrial environment, however it may be that there are other types of microbes and organisms breaking down these hard to break polymers. Furthermore, as large amounts of plastic end up in our oceans, focusing there and identifying new microbes and pathways can give a holistic understanding and illustrate what happens to the plastics in the marine environment. This can help answer questions on how the break down is facilitated, how the total ecosystem is impacted and the process of biodegradation. Q: Do you envision P. album could be used to reduce plastic waste industrially? A: Microbes are well-known for being used to mitigate pollution and environmental disasters, such as when oil pollution occurs on land. However, further research is required to determine if P. album is the best candidate for plastic degradation on an industrial scale. It is just the first step to identify the organisms, how they function and which plastics can they degrade. To tackle the massive problem of plastic pollution on an industrial scale is something that one hopefully can address in the future. However, the sooner the better, as plastic is still piling up in oceans and the problem is only growing. Dr. Annika Vaksmaa was speaking to Kate Robinson, Assistant Editor for Technology Networks. About the interviewee: Dr. Annika Vaksmaa is a postdoctoral researcher at the Royal Netherlands Institute for Sea Research (NIOZ). She obtained a PhD in microbiology from Radboud University Nijmegen in 2017. Microplastics can be either primary (produced in “micro” form e.g., beads in personal care products like facial scrubs) or secondary (larger plastics that are broken down over time). The three main routes through which humans, animals and the environment might be exposed to microplastics are: Key sources of microplastic pollution Water While wastewater treatment plants can remove larger microplastics, smaller particles can evade removal. Microplastics are particularly problematic in our water systems as they are further eroded through physical abrasion, ultraviolet (UV) irradiation and biodegradation into smaller particles, making them more difficult to remove and more easily ingested. Microplastics can enter water systems through: Degraded plastic waste Surface run-off Atmospheric deposition Wastewater and industrial effluent Combined sewer overflows While wastewater treatment plants can remove larger microplastics, smaller particles can evade removalremove larger microplastics, smaller particles can evade removal Untreated raw sewage can enter into superficial water bodies before treatment due to heavy rain. Click here to download the full infographic 17 TECHNOLOGYNETWORKS.COM Credit: iStock Environmental Analysis New Methods To Combat Environmental Pollutants Kate Robinson New headlines appear every day highlighting the detection of pollutants ranging from forever chemicals to microplastics in environments across the globe, but how are scientists fighting back against these unwelcome guests? Here, we explore recent advances in methods to detect and remove the contaminants invading our planet. Nanoconfined Materials Developed for Efficient Fluoride Removal From Water In a study published in Chemical Engineering Journal, researchers reported on the development of an innovative material for the efficient removal of fluoride ions from water. Fluoride is a major water pollutant, with high doses causing dental or skeletal fluorosis, which is linked to osteosclerosis, calcification of tendons and ligaments, and bone deformities. Layered double hydroxides (LDHs) are effective at removing fluoride, however, they are prone to material aggregation during preparation, which leads to a significant decrease in adsorption capacity. Because of this, it’s important to design LDH materials that fully expose their active sites to efficiently remove fluoride ions. The new material, called La-Mg LDH/Ti3C2TX, was developed by combining La-Mg LDH with Ti3C2TX to help prevent the sheets from clumping together. After being used and regenerated five times, the material was still able to remove over 80% of the fluoride ions from water. In addition, the levels of magnesium, titanium, and lanthanum in the filtered water remain below national safety standards, demonstrating that the material is stable and safe. “Our study could lead to more effective methods for water purification,” said Dr. Junyong He, a member of the research team, Hefei Institutes of Physical Science, Chinese Academy of Sciences. Atom-Thin Graphene Membranes Make Carbon Capture More Efficient Scientists from the Swiss Federal Institute of Technology Lausanne (EPFL) have developed advanced atomthin graphene membranes that show unprecedented performance in CO2 capture. The need for efficient and cost-effective carbon capture technologies is more urgent than ever, as the war against climate change rages on. Carbon capture, utilization and storage (CCUS) is a critical technology used to reduce CO2 emissions from industrial sources, however, current capture methods are costly and unsustainable. In the study, published in Nature Energy, the researchers reported on the development of single-layer graphene films that show exceptional CO2 capture performance by incorporating pyridinic nitrogen at the edges of graphene pores. The membranes were synthesized using chemical vapor deposition on copper foil and the pores were introduced into the graphene through controlled 18 TECHNOLOGYNETWORKS.COM Environmental Analysis oxidation with ozone. The researchers then developed a method to incorporate nitrogen atoms at the pore edge by reacting the oxidized graphene with ammonia. These membranes can significantly reduce the costs and energy requirements of carbon capture processes. The team is now looking to produce these membranes by a continuous roll-to-roll process. Caffeine Levels May Help Pinpoint Polluting Wastewater Leaks In research published in Environmental Chemistry Letters, researchers have suggested that caffeine levels could be used to find likely sources of leaks in wastewater systems. The team collected storm drain water, rainwater, puddle water and domestic sewage samples, in order to measure how frequently compounds consistently detected in domestic wastewater in Japan are found in rainwater and puddle water. They found that polycyclic aromatic hydrocarbons were detected 80% of the time, fragrance compounds were found 60% to 82% of the time and a common sunscreen ingredient was found 90% to 100% of the time. Caffeine was detected less than half the time in rainwater and puddle water, and the level of contamination was distinctly different for rainwater and puddle water, storm drainages and domestic sewage. As there is little recirculation of caffeine into the drainage system via rainfall and the source of any caffeine in runoff could be attributed to domestic sewage, it could be a good tracer for future research. Looking ahead, the team wants to understand more about the pollution caused by these leaks. “We want to clarify the extent of the possible pollution of the receiving public water bodies, such as rivers, lakes or coastal areas, by the leaks,” said Noriatsu Ozaki, an associate professor at Hiroshima University’s Graduate School of Advanced Science and Engineering. “And finally, we want to develop the diagnostic technology to indicate the leakage at the site using the trace organic chemicals as an indicator.” New Spectroscopy Method Simplifies Measurement of Microplastics in Soil Researchers from Waseda University and the National Institute of Advanced Industrial Science and Technology (AIST) have developed a novel method to measure the concentration of microplastics in different soil types. Microplastics are present throughout our environment, having been found in environments across the globe. A significant portion of these pollutants are held in soils, from which they can easily transfer to groundwater and eventually enter the human body. Current techniques for measuring microplastic concentrations in soil require separation of the soil organic matter content, a process during which microplastics are often lost. Following this, techniques that require advanced skills and have limited resolution are typically used. The research, published in Ecotoxicology and Environmental Safety, demonstrates the efficacy of a newly developed spectroscopy-based method to correctly measure the concentration of microplastics in soil, without any cumbersome separation process. The new method uses the difference between the absorbance spectra of microplastics and soil particles to quantify the pollutants. “Our novel measurement approach can quantify different [microplastics], including polyethylene and polyethylene terephthalate, in a variety of soils and can easily be used as an initial assessment tool. Moreover, it can help further our understanding of the distribution and migration behavior of [microplastics] in the geosphere environment,” said Kyouhei Tsuchida, a researcher at AIST and a doctoral student at Waseda University. know is important but is very difficult to get intellectual property on and to sell and to reimburse, what you’ll be left with is very transactional,” says Heifets. “Go to a clinic, take your trip, then leave and do the [therapy] app. The field is at a crossroads will it embrace placebo, using different trial designs and formal definitions of set and setting or remove these factors altogether.” Regardless of the route that the field decides to take, it will have to acknowledge the power of placebo. “I wish I could be more hopeful about decriminalization and commercialization of psychedelics,” he concludes. “I don’t think they’re going to reimburse the right things.” 19 TECHNOLOGYNETWORKS.COM Microplastics: How Do They Spread? Alexander Beadle From remote and pristine regions of the Pyrenees1 to the deep-sea floor,2 small fragments of plastic can be found the world over. With such a broad geographic spread, these microplastics — the umbrella term given to tiny plastic particles or fibers typically measuring less than 5 mm — have become ubiquitous in the modern world. Broadly, microplastics can be divided into two categories: primary and secondary microplastics.3 Primary microplastics are plastic particulates designed for commercial use, such as the microbeads sometimes included in personal care products or the synthetic fibers shed from clothes during washing. In contrast, secondary microplastics are formed when larger plastic products, such as discarded bottles or plastic bags, begin to decompose and break down in the environment. Once these particles enter the environment, there is a risk that the microplastics could be unknowingly ingested by fish, local animals or humans who might eat contaminated foods. While the health effects of microplastics are still not fully understood, current research indicates that microplastic exposure can cause tissue damage, oxidative stress and changes in immune-related gene expression for marine life.4 In humans, accidental consumption is also thought to be linked to problems with cytotoxicity, neurotoxicity, immune system disruption and lead to the accumulation of microplastics in different body tissues.4 But how does this exposure happen? Research suggests that our soil, waterways and even the air around us can all be a source of microplastic contamination. Fortunately, researchers have a number of tools at their disposal that can help to identify and quantify cases of serious contamination,5 with several commercial-scale cleanup technologies also helping to stop the continued spread of such microplastics Routes of microplastic contamination There are three main avenues through which humans, animals and the wider environmental ecosystem might be exposed to microplastics. These are: Soil There are multiple routes that microplastics might take to enter the soil.6 The breakdown of discarded plastic items that have been sent to landfill is a major contributor to this. Other sources of contamination might include tire wear and tear, soil amendments or the spreading of contaminated sewage sludges or wastewater on farmland. Once they are in the soil, microplastics can have a significant impact on their local environment. Plants may struggle with proper nutrient metabolism and absorption if microplastics are present at high enough levels, as the microplastics can disrupt soil microorganisms and thus affect the normal microbiome.7 There is also the risk that microplastics could enter the broader food chain once they have been introduced to fertile land, increasing the risk of accidental consumption by animals and humans. Environmental Analysis Credit: iStock 20 TECHNOLOGYNETWORKS.COM Environmental Analysis Current research indicates that microplastics may also act as a vector for other harmful pollutants, carrying residual chemicals into new environments where they could present additional risks to life.8 Water Microplastics may be present in seawater, freshwater, wastewater or groundwater, although the exact source of the plastic does vary significantly. Microplastic fibers may be relatively common in seawater, for example, as fishing nets begin to degrade and release material into the oceans. The microplastics found in wastewater are more likely to be primary microplastics from personal care products being used and washed down the drain.9 Rainwater is another interesting case, as this water can act as a powerful vector that transports microplastics out into soil or other aquatic environments, often picking up other contaminants along the way. One study conducted in the Nakdong River, South Korea, found that between 70–80% of the annual microplastic load is moved during the country’s rainy season.10 In a marine environment, microplastics will gradually fragment into greater numbers of smaller microplastic particles through physical abrasion, ultraviolet (UV) irradiation and biodegradation. At such small particle sizes, these microplastics may pose even more substantial risks to aquatic life by penetrating cell membranes and causing cellular damage.9 This presents a significant danger to the rest of the food chain too, as predators run the risk of consuming prey containing large amounts of plastic accumulated in their tissues, thus furthering the spread of these microplastics. Air Due to their incredibly small size and low density, it is also possible for microplastics to be picked up in the wind and blown from place to place.11 This means that humans and animals are actively breathing in atmospheric microplastics as they go through daily life. Indeed, current research simulations suggest that humans may breathe in nearly 300 microplastic particles during a day of light activity.12 Microplastic particles have already been found in human lung tissue samples, however, there is still a general lack of information regarding the effects of these particles on the respiratory system and the mechanisms through which they might contribute to lung disease.13 How is microplastic contamination detected? Visual inspection using a microscope or stereoscope can be sufficient to detect the presence of microplastics in simple sample matrices. Despite being a relatively time-consuming technique, even when assisted by the use of special dyes, a recent review estimates that visual inspection is still used in just under one-third of microplastic analyses of water and sediment samples.14 According to the same review, the most frequently used methods of analysis for water and sediment samples are Fourier-transform infrared spectroscopy (FTIR)- based methods. This spectroscopy technique uses the vibrational modes of different molecules in order to identify certain characteristic structures within a sample that will indicate its chemical makeup. Raman spectroscopy, another vibrational spectroscopy method, is also commonly used for microplastic analysis. Pyrolysis-gas chromatography-mass spectrometry (pyro-GC-MS) is another frequently used method of analysis wherein microplastic samples are pyrolyzed in an inert atmosphere and the resulting gases are analyzed.14 By its nature, this method is destructive and does not allow an analyst to glean any information regarding the number of microplastic particles in a given sample. However, for the bulk analysis of a large sample, this technique can provide very accurate characterizations of the different plastics present within very complex matrices. Microplastic remediation An effective microplastic remediation technique must take care not to create more microplastics inadvertently, either through incomplete degradation or additional fragmentation. For this reason, coagulation is one of the most frequently used techniques for removing microplastics at commercial wastewater treatment facilities.15 The technique works by using different chemical coagulants to destabilize the microplastic particles suspended in the wastewater, promoting sedimentation and easy removal when passed through a filter. However, the technique is not a perfect solution to microplastic pollution. At the industrial level, the coagulation process will produce significant amounts of sludge that may pose its own risk to the environment if not adequately treated. There are other, more experimental techniques for microplastic remediation that are currently being trialed.15 One of these is photocatalytic degradation. This method makes use of a semiconductor material that absorbs visible or UV light and, in the process, generates free radicals, which degrade the microplastics. However, while this technique does effectively destroy microplastic particles, it still generates some sludge waste that must be monitored and disposed of carefully to prevent damage to the environment. Environmental Analysis 21 TECHNOLOGYNETWORKS.COM Another novel technique that is attracting significant attention is electrocoagulation. A sustainable and costeffective alternative, electrocoagulation operates on the same principle as traditional coagulation but without the use of chemical coagulating agents. In electrocoagulation, metallic electrodes are used to produce cations that can promote flocculation between the microplastic particles. This produces significantly less sludge waste than the traditional approach, which is a boon for both the environment and the wastewater treatment plant, that no longer has to deal with the expensive post-processing and monitoring steps needed for proper sludge disposal. As a material, plastic has revolutionized our modern world. Its impressive durability and strength-toweight ratio has enabled significant advancement in a wide variety of disciplines, including building and construction, electronics, textiles, consumer products and transportation. But now more than ever, scientists are aware of the dangers presented when these products are disposed of improperly and are allowed to break down to form harmful microplastics. For today’s researchers, it is crucial that we improve our understanding of how these plastic particles are being spread, so that actions can be taken to remediate cases of contamination and stem the flow of these plastics into our environment. Participants in the study were severely allergic to peanuts and at least two other foods. After four months of monthly or bimonthly omalizumab injections, two-thirds of participants were able to eat small amounts of their allergytriggering foods safely. Upon re-testing, 66.9% of patients who had taken omalizumab could tolerate at least 600 mg of peanut protein, the amount in two or three peanuts, compared with only 6.8% who had the placebo. Similar proportions of patients showed improvement in their reactions to the other foods in the study. “Patients impacted by food allergies face a daily threat of life-threatening reactions due to accidental exposures,” said Robert Wood, lead author of the study and professor of pediatrics at Johns Hopkins University School of Medicine. “The study showed that omalizumab can be a layer of protection against small, accidental exposures.” Reference 1. Allen S, Allen D, Phoenix VR, et al. Atmospheric transport and deposition of microplastics in a remote mountain catchment. Nat Geosci. 2019;12(5):339-344. doi:10.1038/ s41561-019-0335-5 2. Barrett J, Chase Z, Zhang J, et al. Microplastic pollution in deep-sea sediments from the great australian bight. Front Mar Sci. 2020;7. doi:10.3389/fmars.2020.576170 3. Microplastics: sources, effects and solutions. European Parliament. Published November 22, 2018. Accessed June 1, 2023. https://www.europarl.europa.eu/news/ en/headlines/society/20181116STO19217/microplasticssources- effects-and-solutions 4. Bhuyan MdS. Effects of microplastics on fish and in human health. Front Environ Sci. 2022;10. doi:10.3389/ fenvs.2022.827289 5. Bose P. Microplastic detection. Technology Networks. Published August 31 2021. Accessed June 1, 2023. http:// www.technologynetworks.com/applied-sciences/articles/ microplastic-detection-353032 6. Guo JJ, Huang XP, Xiang L, et al. Source, migration and toxicology of microplastics in soil. Environ Int. 2020;137:105263. doi:10.1016/j.envint.2019.105263 7. Sun Y, Yang C, Liang H, et al. Health risk analysis of microplastics in soil in the 21st century: A scientometrics review. Front Environ Sci. 2022;10. doi:10.3389/ fenvs.2022.976237 8. Sajjad M, Huang Q, Khan S, et al. Microplastics in the soil environment: A critical review. Environ Technol Innov. 2022;27:102408. doi:10.1016/j.eti.2022.102408 9. Kye H, Kim J, Ju S, Lee J, Lim C, Yoon Y. Microplastics in water systems: A review of their impacts on the environment and their potential hazards. Heliyon. 2023;9(3):e14359. doi:10.1016/j.heliyon.2023.e14359 10. Eo S, Hong SH, Song YK, Han GM, Shim WJ. Spatiotemporal distribution and annual load of microplastics in the Nakdong River, South Korea. Water Res. 2019;160:228-237. doi:10.1016/j.watres.2019.05.053 11. Abad López AP, Trilleras J, Arana VA, Garcia-Alzate LS, Grande-Tovar CD. Atmospheric microplastics: exposure, toxicity, and detrimental health effects. RSC Adv. 13(11):7468-7489. doi:10.1039/d2ra07098g 12. Vianello A, Jensen RL, Liu L, Vollertsen J. Simulating human exposure to indoor airborne microplastics using a Breathing Thermal Manikin. Sci Rep. 2019;9:8670. doi:10.1038/s41598-019-45054-w 13. Lu K, Zhan D, Fang Y, et al. Microplastics, a potential threat to patients with lung diseases. Front Toxicol. 2022;4:958414. doi:10.3389/ftox.2022.958414 14. Prata JC, da Costa JP, Duarte AC, Rocha-Santos T. Methods for sampling and detection of microplastics in water and sediment: A critical review. TrAC Trends Anal Chem. 2019;110:150-159. doi:10.1016/j.trac.2018.10.029 15. Osman AI, Hosny M, Eltaweil AS, et al. Microplastic sources, formation, toxicity and remediation: a review. Environ Chem Lett. 2023. doi:10.1007/s10311-023-01593-3 22 TECHNOLOGYNETWORKS.COM Water Analysis: A Pollution Solution? Matt Hallam Water is an essential ingredient for life on Earth – and possibly beyond. For modern humans, water represents a means to hydrate, wash, cook, clean and even to dispose of our waste. But our activities are not without consequences. Every headline about pollutants like microplastics and forever chemicals (namely per- and polyfluoroalkyl substances) is a daunting reminder that our presence on this planet has a direct impact on the quality of its water. Understanding this impact could help us to improve water quality and avoid the potential adverse effects of contaminants. But how big is the problem? What tools are used to quantify it? And how can this knowledge help us? The tools of the trade “There are over 200 parameters that we can analyze when assessing water quality and most of these are source- and location-specific,” said Dr. Sarper Sarp, a senior lecturer at Loughborough University. Among these parameters are a wide variety of contaminants. Though many researchers have focused on traditional pollutants (like nutrients and heavy metals), so-called emerging pollutants are now taking center stage. “There isn’t enough information about emerging pollutants and their impact,” explained Prof. Rachel Gomes, a professor of water and resource processing at the University of Nottingham. “These include pharmaceuticals, microplastics, and microorganisms that have developed resistance to commonly used antimicrobials.” The impact of these pollutants is widely documented: microplastics were identified in human breastmilk in 20221 and antimicrobial resistance caused an estimated 1.27 million deaths globally in 2019.2 The choice of technique used for water analysis is largely driven by the application and target. A combination of gas (GC) or liquid chromatography (LC) with mass spectrometry (MS) can prove effective for targeted and untargeted contaminant identification, but each approach has its own strengths (and preferred targets). MS variants, like matrix-assisted laser desorption/ionization time-offlight MS, can also be applied to study microorganisms in water sources.3 Some contaminants might be identified via Raman spectroscopy, which studies the vibrational modes of molecules and requires minimal sample preparation. Biosensors, which convert biological signals into a measurable response, also represent a viable option with high sensitivity and selectivity and the potential for miniaturization.4 Of course, other techniques – like genomic methods – are available for specific applications. And, as may be expected, our analytical capabilities have changed (and will continue to change) over time. As Sarp said: “We used to be able to detect contaminants at the parts per million level in water; now we can study them at parts per trillion. The driving force is knowledge – and the fact that some of these chemicals can be toxic at extremely low concentrations.” Environmental Analysis Credit: iStock Environmental Analysis 23 TECHNOLOGYNETWORKS.COM Life in plastic Of all the analytes that scientists study in water, plastics have probably received the greatest level of media attention in recent years. Worldwide familiarity with microplastics is testament to this coverage, but how problematic are they? “Microplastics were a big focus in research a few years ago,” Sarp explained. “But microplastics often leave the body without a negative impact because of their chemical inertness and large size. I wondered if we could study nanoplastics instead, which are small enough to penetrate cell walls and cause toxicity. We did so by combining nanofiltration with pyrolysis GC-time-of-flight MS (considered the best technique to identify specific plastics). Our approach made the analysis of nanoplastics in water possible for the first time.”5 But simply detecting these plastics is not enough. “The wider context around plastics is also important to consider,” Gomes said. “What type of polymer are we looking at? Are they weathered or pristine (unweathered, or as manufactured)? What is their size and distribution? Not all microplastics are created equal. How do their individual qualities influence their fate and impact? And are the samples analyzed truly representative of the wider water environment being studied? These factors must be explored to gain a full understanding of the problem.” Combatting COVID Wastewater represents a powerful analytical target because an estimated 2.1 billion people are connected to wastewater treatment processes around the world.6 Many scientists have used – and are still using – this water as an opportunity to study COVID-19. Rolf Halden and colleagues began using the quantitative polymerase chain reaction and metagenomic approaches to study SARS-CoV-2 particles in wastewater on a regular basis in Tempe, Arizona, during the early days of the pandemic. The hope was to identify local infection hotspots, and the online dashboard still boasts results from these analyses.7 A study led by clinician Dr. Tanya Monaghan at the University of Nottingham accomplished a similar feat in Nagpur, India. The team, which included Gomes, applied RNA sequencing to retrospectively measure SARS-CoV-2 and other zoonotic viruses from a total of 140 sample sites and identified SARS-CoV-2 in 59% of the locations studied (though the levels of virus varied massively between sites).8 They also detected several infectious agents in wastewater for the first time – including Jingmen tick, chikungunya, and rabies viruses – but Hepatitis C was the most common virus detected. Studies like this provide an opportunity to assess the health status of large populations and can help to direct interventions against the diseases present. Sarp’s contributions to the fight against COVID-19 via wastewater analysis again focused on nanoplastics. “When the pandemic started, we shifted our focus to facemasks and whether they emit nanoplastics once disposed of,” he said. “To our surprise, we found that each mask released thousands of nanoparticles, some of which were laced with heavy metals like arsenic, lead and copper. The potential impact of these findings could be huge.” What’s next? Water analysis is essential to protect people and our planet, but we have a long way to go to truly understand and ensure the quality of our water. Part of the problem is the limitations of our current knowledge and technologies. “We need to answer a number of key questions,” Gomes explained. “Which emerging pollutants should be treated as a priority? Can current treatment technologies remove them? How can we improve these technologies where needed, and what new technologies or strategies might be necessary?” Essential technological advances will include the development of cheap and mobile analytical equipment, as well as remote sensing capabilities and end user-based monitoring. Another important issue to address will be inequity in water analysis between geographies. “Analytical approaches and their availability need to be more inclusive,” Gomes said. “Access to LC-MS/MS instrumentation is limited in some countries and existing machines tend to become outdated very quickly. This is driven partly by the need for ever-decreasing detection limits. Determinations of environmental risk using predicted no effect concentrations (PNECs; the level at which a contaminant is thought to have no negative impact) could also be modified to be more geographically equitable. Current PNECS tend to focus on European aquatic species, but are also applied to other regions where they may not be relevant. Ways to reduce contamination levels in water without the need for expensive technologies and processes are needed, too.” Ambitious targets like the 9% reduction in microplastics by 2040 proposed by the European Commission9 paint a picture of a bright (and clean) future. Perhaps suggestions like those above can help us to achieve it. About the interviewees Dr. Sarper Sarp is a senior lecturer in the School of Architecture, Building and Civil Engineering at Loughborough University. His research focuses on water quality, micropollutant monitoring in water, and water treatment systems. Prof. Rachel Gomes is a professor of water and resource processing in the Faculty of Engineering at the University of Nottingham. Her research focuses on wastewater and reuse, 24 TECHNOLOGYNETWORKS.COM Environmental Analysis with an emphasis on pollutants, water quality, and waste valorization opportunities. Dr. Tanya Monaghan is a clinical associate professor and honorary consultant in gastroenterology in the Faculty of Medicine and Health Sciences at the University of Nottingham. Her current research interests include developing wastewater-based epidemiological approaches to understand population health in East Africa and India. References 1. Ragusa A, Notarstefano V, Svelato A, et al. Raman microscopy detection and characterisation of microplastics in human breastmilk. Polymers. 2022. doi: 10.3390/polym14132700 2. Antimicrobial resistance. World Health Organization. https://www.who.int/news-room/fact-sheets/detail/ antimicrobial-resistance. Published November 21, 2023. Accessed March 19, 2024. 3. Jiang W, Lin L, Xu X, et al. A critical review of analytical methods for comprehensive characterization of produced water. Water. 2021. doi: 10.3390/w13020183 4. Zakir Hossain SM, Mansour N. Biosensors for on-line water quality monitoring – a review. Arab J Basic Appl Sci. 2019. doi: 10.1080/25765299.2019.1691434 5. Sullivan GL, Delgado Gallardo J, Jones EW, Holliman PJ, Watson TM, Sarp S. Detection of sub-micron (nano) plastics in water samples using pyrolysis-gas chromatography time of flight mass spectrometry (PY-GCToF). Chemosphere. 2020. doi: 10.1016/j. chemosphere.2020.126179 6. Hart OE, Halden RU. Computational analysis of SARSCoV- 2/COVID-19 surveillance by wastewater-based epidemiology locally and globally: Feasibility, economy, opportunities and challenges. Sci Total Environ. 2020. doi: 10.1016/j.scitotenv.2020.138875 7. Biomarker: COVID-19. Tempe Wastewater BioIntel Program. https://wastewater.tempe.gov/pages/ biomarker-covid19. Accessed March 19, 2024. 8. Stockdale SR, Blanchard AM, Nayak A, et al. RNA-Seq of untreated wastewater to assess COVID-19 and emerging and endemic viruses for public health surveillance. Lancet Reg Health Southeast Asia. 2023. doi: 10.1016/j. lansea.2023.100205 9. Urban wastewater. European Commission. https:// environment.ec.europa.eu/topics/water/urbanwastewater_ en. Accessed March 19, 2024. There have been relatively few studies investigating the sources of emerging PFAS. The few studies that have been done suggest that their presence in the environment is primarily the result of direct emissions from fluorochemical manufacturing. Short-chain PFAS compounds generally have a shorter half-life in the environment than long-chain legacy PFAS. Still, HFPO-DA has been detected alongside other legacy PFAS in Arctic seawaters, suggesting that emerging PFAS also have the potential to travel long distances and become global contaminants if left unaddressed. Direct emissions from local fluorochemical production Degradation of other fluorinated substances Long-range transport A 2015 study of surface water in the US found traces of HFPO- DA, a PFOA substitute, and other new PFAS in geographic egions with historic legacy PFAS contamination. A 2017 study of river and drinking water in the Netherlands found HFPO-DA and other emerging PFAS downstream from a fluorochemical production plant, suggesting the plant was the source of the compound. Click here to download the full infographic 26 TECHNOLOGYNETWORKS.COM Environmental Analysis Contributors Alexander Beadle Alex is a science writer and editor for Technology Networks. Alexander holds an MChem in Materials Chemistry from the University of St Andrews, Scotland. Kate Robinson Kate Robinson is an assistant editor at Technology Networks. She joined the team in 2021 after obtaining a bachelor’s degree in biomedical sciences. Leo Bear-McGuinness Leo is a science writer with a focus on environmental and food research. He holds a bachelor’s degree in biology from Newcastle University and a master’s degree in science communication from the University of Edinburgh Matt Hallam Matt is a freelance science writer with years of experience producing content. He has a master’s degree in translational oncology from the University of Sheffield. Nick Gaunt, PhD Nick is a multi-award winning science writer and the founder, director and CEO of Acorn Scientific Marketing. He completed a PhD at the University of Exeter focusing on enhancing agrochemistry to bolster food security.