(Beyond Pesticides, July 9, 2013) A recent pesticide contamination incident in Great Britainâ€™s Kennet River has decimated aquatic invertebrate populations on a ten mile stretch of river between the towns ofÂ Marlborough and Hungerford. The contamination occurred after a spill of the toxic pesticide chlorpyrifos entered a Marlborough sewage system. The lack of aquatic invertebrates could lead to a dramatic decline of the riverâ€™s chalk trout population. A similar incident occurred in Great Britain on the Wey River in 2003, and in Sussex Ouse in 2001. This recent calamity helps to underscore the importance for the U.S. Environmental Protection Agency (EPA), across the Atlantic, to fully implement pesticide restrictions that U.S. conservation groups are seeking to enforce through court action.
The damage to the U.K. river may have been caused by, according to an Express article, only two tablespoons of the neurotoxic insecticide chlorpyifos. Members of the public have been advised by Britain’s Environment Agency to avoid skin contact with the water and not to eat fish caught from the river.Â The contamination has occurred at the height of fly-fishing season. Environmental organizations are afraid that a decline in the number of aquatic invertebrates could lead chalk trout and other forms of wildlife to starve. Mark Owen, Freshwater and Environment Campaigns Manger for the Angling, was quoted in an Express article saying, â€śEven if fish stocks remain untouched there is now precious little left for the fish or other wildlife to eat which is why the Angling Trust is calling for measures to try and recolonize the affected stretches with invertebrates as quickly as possible.â€ť
The chemical that contaminated the river, chlorpyrifos, is a neurotoxic insecticide that was banned from residential applications in the U.S. after EPA determined that cumulative exposure resulted in serious adverse health outcomes, especially for children. EPA has left virtually all agricultural uses, with the exception of tomatoes,Â on the market. Chlorpyrifos is acutely toxic to bees, birds, mammals, aquatic life, and certain species of algae. Poisoning from chlorpyrifos affects the central nervous system, the cardiovascular system, and the respiratory system, and causes skin and eye irritation. A study of children exposed to chlorpyrifos in utero found that extensive and unusual patterns of birth defects, including brain, nervous system, eyes, ears, palate, teeth, heart, feet, nipples, and genitalia. The published literature and EPA documents contain reports that identify similarities in defects found in test animals and children exposed to chlorpyrifos.
There are also a wide range of adverse environmental effects linked to chlorpyrifos, including toxicity to: beneficial insects, freshwater fish, other aquatic organisms, bird, a variety of plants, soil organisms, and domestic animals. It has been shown to bioaccumulate in fish and synergistically react with other chemicals. Thus, even if no acute health issues are seen in fish contaminated by this incident, chronic problems may arise in the future.
Though chlorpyrifos use is banned for residential application in the U.S., EPA has not taken action to implement strong measures to protect fish from the threat of chlorpyrifos stream contamination. In 2008 the National Marine Fisheries Service (NMFS) released a biological opinion (BIOp) that set forth a plan to protect salmon and other fish from chlorpyrifos and other toxic organophosphates. Part of this plan included restrictions on sprayed within 500 to 1000 feet of waterways. Four years later, in 2012 Conservation groups filed lawsuits against EPA clamming that the agency had still not implemented the restrictions proposed by the NMFS. This lawsuit came after EPA had already been ordered to consult with NMFS after lawsuits in 2002 and 2007. EPA is mandated by law to protect dwindling species like salmon under the Endangered Species Act, and by failing to implement NMFS buffer mandates, EPA is responsible for endangering salmon.
However, last February a U.S. Court of Appeals found that the pesticide restrictions proposed by NMFS were â€śarbitrary and capricious.â€ť This decision came after The U.S. District Court upheld NMFSâ€™ BiOp in 2011, finding that the BiOp is rationally supported by the â€śvoluminous facts and studies considered by the [Fisheries Service].â€ť Even though this opinion was thrown out, EPA can still force chemical companies to change their labels to include buffer zones and other protections for aquatic life. The recent contamination of the Kennet River underscores the importance for the U.S. EPA to act to protect our threatened waters.
For more information on pesticides and water quality, please visit Beyond Pesticidesâ€™ Threatened Waters page.
All unattributed positions and opinions in this piece are those of Beyond Pesticides.