New study predicts climate change will make pesticides more lethal to fish

Australian scientists have found that fish exposed to sub-lethal concentrations of endosulfan and chlorpyrifos showed significant reductions in the ability to survive in warmer waters. Both endosulfan and chlorpyrifos are commonly used in cotton, horticulture and sugar cane production.

The study published in Environmental Toxicology and Chemistry predicts that global warming will make fish more susceptible to dying from pesticide-contaminated water. According to the study affected fish displayed “erratic swimming…, uncoordinated movement with body quivering, rolling over on sides or back” and loss of the ability to swim upright.

Combine this with the strain already imposed on global fish stocks as a consequence of over-fishing by commercial operators and it’s not difficult to envisage a future without many popular fish varieties.

So, what exactly are endosulfan and chlorpyrifos?

According to the Pesticide Action Network of North America, endosulfan is an antiquated insecticide. Here are some facts about endosulfan:

• It is highly toxic and persistent
• It has been banned in the European Union
• It is used extensively throughout rural U.S., India, China, and many other countries.
• Studies indicate that it endangers the health and wellbeing of children, farmworkers, and those living proximate to affected areas
• Poisoning symptoms include headaches, nausea, vomiting, seizures, and in extreme cases unconsciousness and even death
• It is a suspected endocrine disruptor, with low dose exposure while in the womb being linked to autism, male reproductive harm, and birth defects.

Much like endosulfan, chlorpyrifos is a dangerous yet widely used pesticide. Here are some facts about chlorpyrifos:

• It is a neurotoxic organophosphate insecticide, acaricide and miticide used to control foliage and soil-borne insect pests on a variety of food and feed crops.
• About 20 million pounds of chlorpyrifos are applied in the U.S. every year according to the EPA, with about half for agricultural uses and half for residential uses
• Until recently it was used extensively in homes for pest control (mostly as a termiticide and in pet flea collars)
• It causes cholinesterase inhibition in humans which can result in nausea, dizziness, confusion, respiratory paralysis and even death.

What can be done?

Studies such as this are an important reminder of the need to remove dangerous pesticides from our food chain. Apart from the obvious potentially adverse health consequences associated with pesticide use, their persistent nature means that many of them will continue to wreak environmental havoc long after their initial application. Here are some steps to take if you’re keen to remove pesticides from our food chain:

• Support organic agriculture
• Join PANNA.
• Write to your local politician requesting that endosulfan and chlorpyrifos be banned from use.