The pesticides involved in the study include organophosphates and organochlorines used by 18,782 farmers in Iowa and North Carolina. Some of the pesticides, including DDT, have been banned, but others are still on the market. However, this new study may help urge farmers to cut down on their pesticide use, if for no other reason than their own health.
U.S. farmers exposed to agricultural insecticides are at risk for neurological problems even if the products no longer are used, government researchers said.
A study by the National Institute of Environmental Health Sciences, the National Cancer Institute and the Environmental Protection Agency is available online and will be included in the print June edition of the journal Environmental Health Perspectives.
The study included data from 18,782 North Carolina and Iowa farmers and linked use of insecticides, including organophosphates and organochlorines, to reports of reoccurring headaches, fatigue, insomnia, dizziness, nausea, hand tremors, numbness and other neurological symptoms.
Some of the insecticides in the study are still on the market, but some, including DDT, have been banned or restricted.
Researchers found nearly 3,000 study participants had a high lifetime exposure to insecticides -- they used insecticides more than 500 days in their lifetime.
Nearly 800 of these farmers reported more than 10 neurological symptoms compared to those using insecticides fewer than 50 days.
The researchers did not find a significant association between neurological symptoms and other chemicals, including herbicides or fungicides.