Herbicides responsible for farmer depression?

July 2013

A study of more than 700 French farmers and farmworkers found that those who used herbicides were more likely to be treated for depression than were those who avoided the stuff.

When the researchers took into account factors linked with depression, such as age and cigarette smoking, they determined that those farmers exposed to weedkillers were nearly two and a half times as likely to have had depression.

Furthermore, farmers who had greater exposure – either more hours or longer years using herbicides – also had a greater chance of having depression than farmers who had used weedkillers less.

The researchers can’t say whether chemicals in the weedkillers actually caused the depression. More work would be needed to make that link.

The study, which was published in the American Journal of Epidemiology, states: »The possibility that environmental contaminants could affect psychological health has been generally underappreciated. Herbicide exposure in particular has received little research attention. If true, our findings have important public health implications for agricultural workers given the tremendous public health burden of depression and the fact that herbicides are widely used in agriculture and landscape management. In the United States, herbicides make up about 65% of all agricultural pesticide use.«

Marc Weisskopf, the study’s lead author and an associate professor at the Harvard School of Public Health, underlined that the new research »raises concerns that need to be looked into more fully« and is a reminder that »we should not be ignoring herbicides« when considering pesticide hazards.

Pesticide Exposure and Depression Among Agricultural Workers in France