[The pesticide endosulfan is used extensively to protect cotton crops in Australia. The following report from the Pesticide Action Network North America Updates Service documents serious problems with endosulfan in the United States.]
In August 1995, pesticide-contaminated run-off from cotton fields resulted in a huge fish kill in Alabama. State personnel estimate that more than 240,000 fish of all locally known species were killed along a 25 km stretch of the Big Nance Creek, which flows into the Tennessee River.
Water quality tests at three locations indicate that concentrations of endosulfan, an organochlorine insecticide applied to cotton fields, were at levels almost two times higher than that known to kill fish. In addition to being extremely toxic to fish and other aquatic life, endosulfan is reported to disrupt the endocrine and reproductive systems of both humans and wildlife.
According to state officials, a pesticide product was sprayed by both airplanes and tractor-type applicators on about 10 farms in early August near Big Nance Creek. The product, made by FMC Corporation of Philadelphia, contains a combination of methyl parathion and endosulfan.
Heavy rains occurred in the area shortly after some of the applications. In addition to the Big Nance Creek incident, pesticide run-off is also suspected as the cause of several smaller fish kills in the area during the same period.
The Alabama Department of Environmental Management, the departments of Agriculture and Industry, Public Health and Conservation and Natural Resources announced after a three-week investigation that "heavy rains, an epidemic of cotton worms and improper labelling of a pesticide all played a role in the fish kill".
According to their findings, there was no indication that endosulfan was applied in an illegal manner. The director of the plant protection division of the Department of Agriculture and Industries stated, "It was primarily a run-off situation of normal or proper application of a pesticide to a crop site".
Investigators also found that labels on the pesticide containers did not include a warning that it should not be applied within 300 feet [90 metres] of lakes, ponds, streams and estuaries because of its toxicity to aquatic life. They stated that some of the fields where the pesticide was applied may be slightly less than 300 feet from the creek.
FMC Corporation stated that literature distributed with the pesticide product contains the warning, but confirmed that it is not included on container labels. FMC officials offered no explanation for the lack of warning information, but stated that the issue is "under investigation." The product literature was not distributed to farmers using the pesticide in this region. There are no charges pending at this time.
One farmer stated that she used endosulfan only because beet army worms and bud worms had reached epidemic levels after becoming resistant to the pesticides normally used to control these cotton pests. After learning that the chemical was suspected of causing the fish kill, the farmer stated that she sent all endosulfan stocks on her farm back to the distributor.