The Danger of Dioxins - Solutions To Keep Us Safe

To protect consumer’s health, the food and drinks industry test products at every stage of production for a multitude of hazards, from pesticides, to microbes and trace chemical contaminants. One group of contaminants that are getting particular attention are dioxins and related chemicals. Even trace levels can accumulate and persist in the environment and pass into the food chain where they can be extremely toxic and cause lasting damage. Therefore, sensitive and effective detection is imperative.

We spoke to Fausto Pigozzo, director of workflow development for food and beverage, Thermo Fisher Scientific, about the problems that dioxins pose for consumers and analysts, and how their solutions are improving detection.

Karen Steward (KS): Why is the quantification of dioxins in food and feed so important? What are some of the most common sources?

Fausto Pigozzo (FP): Dioxins/furans and dioxin-like polychlorinated biphenyls (dl-PCBs) are environmental pollutants generated as unintentional by-products from waste combustion processes or industrial chemical manufacturing processes like the synthesis of chlorinated pesticides. They are classified as persistent organic pollutants and have been labelled as a significant risk to human health at any level and even carcinogenic by the NIEHS (National Institute of Environmental Health Sciences). Action can be taken to actively reduce the amount of dioxins generated from these processes, but they cannot be completely eliminated as by-products. 

Once dioxins are introduced to an ecosystem, they can easily persist and accumulate, contaminating the local environment and entering the food chain. As a result, foodstuff is considered the primary source of human exposure to dioxins, with some studies indicating that food and feed can account for up to 90 % of human exposure to this highly toxic class of compounds. Once this toxic substance enters the body, it accumulates over time within the organisms’ fat stores as a result of its lipophilicity, and the fact that it cannot be easily metabolized and excreted. It is this mass effect that leads to a toxic accumulation of dioxins over a lifetime, and its resulting health effects. 

KS: Are there any sample types that are particularly challenging for dioxin analysis?

FP: Usually, the extraction and separation of dioxins from other compounds found in a sample is the biggest challenge that laboratories face. Processed foods that combine ingredients into a final product can further complicate the matrix with chemical additives.

KS: What does the Thermo Scientific Dioxin Analyzer offer that other available options do not?

FP: The Thermo Scientific Dioxin Analyzer allows for the cost-effective high sample-throughput monitoring of maximum levels and action levels of dioxins/furans and dl-PCBs in foodstuffs and animal feeds. To support the validity of data reported within the framework of official controls by the European Union, testing laboratories are required ¬– for each analytical sequence – to demonstrate, compliance with quality performance criteria ranging from sensitivity to accuracy, as well as method compliance. In particular, the limit of quantitation (LOQ) for each of the most toxic congeners needs to be confirmed by checking the consistency of the response at the lowest concentration level of a calibration curve. Leveraging the benchmark sensitivity of the Thermo Scientific TSQ 9000 Triple Quadrupole GC-MS/MS system combined with the Advanced Electron Ionisation (AEI) source, the Dioxin Analyzer provides the confidence to meet all compliance criteria at the lowest LOQ levels. This level of sensitivity also enables users to lower sample weights, reducing both the cost of sample preparation and system maintenance. Furthermore, the built in Thermo Scientific Chromeleon Chromatography Data System (CDS) software enables scientists to deal with the complex calculations required to process and report data using isotopic dilution. This eliminates the need for a laboratory to adopt multiple external software tools to process, analyze and report their data.

KS: Could dioxins be tested for by a non-expert using this workflow?

FP: Dioxin analysis is one of the most complex workflows that a food safety laboratory could undertake. It requires a high level of expertise, from the extraction/clean up procedure to instrument setup, data interpretation and calculation. Given this, it is recommended that dedicated, skilled technicians should analyze food and feed samples for dioxins.

KS: Are there any challenges that remain to be addressed in the analysis of dioxins and how are you approaching them?

FP: While the analytical workflow is automated, the extraction and clean-up of dioxins from food matrices is still a tedious and expensive process for laboratories to perform.  However, Thermo Fisher Scientific is offering equipment to address these challenges. For example, the Thermo Scientific Dionex ASE 350 Accelerated Solvent Extractor combines elevated temperatures and pressures to increase the efficiency of the extraction process, which results in faster extraction times and significantly reduces solvent usage.

Fausto Pigozzo was speaking to Dr Karen Steward, Science Writer for Technology Networks.