A new study recently published in the American Journal of Epidemiology has found that men who live near large industrial farms have an increased risk of prostate cancer compared to men who live farther away.
For the study, researchers recruited 173 men between the ages of 60 and 74 who were identified by the California Cancer Registry as having prostate cancer and living in Tulare, Fresno or Kern counties — counties with large swaths of industrial agricultural farms in central California. They also used Medicare lists and tax records to find 1,212 men aged 65 years and older who did not have prostate cancer and recruited 162 of them to participate in the study as a control group.
To compare pesticide exposure for the two groups of men, researchers compiled data on each man's living quarters and job history between the years of 1974 and 1999. These locations were matched with and compared to historical data gathered from California pesticide use reports on of each area's reported agricultural pesticide use.
They looked at the pesticide methyl bromide, the fungicide captan, and eight organochlorine pesticides that have been linked to prostate cancer in other studies. Three additional chemicals — maned, paraquat and simazine — were evaluated as control exposures.
The researchers found that the men who lived near large industrial farms that sprayed methyl bromide had a 1.62-fold increased risk of prostate cancer compared to the men who were never exposed to this pesticide. Men who were exposed to organochlorine pesticides showed a 1.64 increase risk over men who were not exposed. Researchers found no associated increase in risk between the other commonly applied pesticides, including maned, paraquat and simazine and prostate cancer.
A number of studies have been conducted on the effects of pesticides on farm workers, and many of the studies found links between pesticide exposure and prostate cancer risk. But this was the first study to look at the effects of these chemicals on men who don't work at the farm but merely live near it — men who are exposed to these chemicals indirectly, via chemical drift when fields are sprayed onto neighboring properties or into drinking water.
We can't draw conclusions based on the results of one study, but it doesn't bode well for men who currently live near this kind of large farm.