Permitted Water Pollution Discharges and Population Cancer and Non-Cancer Mortality
News May 01, 2012
The study conducts statistical and spatial analyses to investigate amounts and types of permitted surface water pollution discharges in relation to population mortality rates for cancer and non-cancer causes nationwide and by urban-rural setting. Data from the Environmental Protection Agency's (EPA) Discharge Monitoring Report (DMR) were used to measure the location, type, and quantity of a selected set of 38 discharge chemicals for 10,395 facilities across the contiguous US. Exposures were refined by weighting amounts of chemical discharges by their estimated toxicity to human health, and by estimating the discharges that occur not only in a local county, but area-weighted discharges occurring upstream in the same watershed. Centers for Disease Control and Prevention (CDC) mortality files were used to measure age-adjusted population mortality rates for cancer, kidney disease, and total non-cancer causes. Analysis included multiple linear regressions to adjust for population health risk covariates. Spatial analyses were conducted by applying geographically weighted regression to examine the geographic relationships between releases and mortality.
Greater non-carcinogenic chemical discharge quantities were associated with significantly higher non-cancer mortality rates, regardless of toxicity weighting or upstream discharge weighting. Cancer mortality was higher in association with carcinogenic discharges only after applying toxicity weights. Kidney disease mortality was related to higher non-carcinogenic discharges only when both applying toxicity weights and including upstream discharges. Effects for kidney mortality and total non-cancer mortality were stronger in rural areas than urban areas. Spatial results show correlations between non-carcinogenic discharges and cancer mortality for much of the contiguous United States, suggesting that chemicals not currently recognized as carcinogens may contribute to cancer mortality risk. The geographically weighted regression results suggest spatial variability in effects, and also indicate that some rural communities may be impacted by upstream urban discharges.
There is evidence that permitted surface water chemical discharges are related to population mortality. Toxicity weights and upstream discharges are important for understanding some mortality effects. Chemicals not currently recognized as carcinogens may nevertheless play a role in contributing to cancer mortality risk. Spatial models allow for the examination of geographic variability not captured through the regression models.
The article is published online in the International Journal of Health Geographics and is free to access.
Off Road Diesel Vehicles Contribute to PollutionNews
Wildfires, cigarette smoking and vehicles all emit a potentially harmful compound called isocyanic acid. The substance has been linked to several health conditions, including heart disease and cataracts. Scientists investigating sources of the compound have now identified off-road diesel vehicles as a major contributor.READ MORE
Algae Could Feed and Fuel Planet with Aid of New High-Tech ToolNews
Vast quantities of medicines and renewable fuels could be produced by algae using a gene-editing technique, a study suggests. The technique uses molecules that act like scissors to cut DNA - called CRISPR molecules - which allow researchers to add new genes or modify existing ones. Until now, scientists have struggled to develop a technique that works efficiently in algae.READ MORE
Marine Microbes may be Responsible for Production of the Greenhouse GasNews
Industrial and agricultural activities produce large amounts of methane, a greenhouse gas that contributes to global warming. Many bacteria also produce methane as a byproduct of their metabolism. Some of this naturally released methane comes from the ocean, a phenomenon that has long puzzled scientists because there were no known methane-producing organisms living near the ocean’s surface but new evidence is helping to solve the mystery.READ MORE