Sanet Post, Dale Wilson
RE: Cancer and Farmers
March 4, 1999
The same kind of situation may exist in the occupational side of pesticide risk. Probably there are a small number of genuinely carcinogenic pesticides (phenoxy herbicides or dioxin contaminants are strongly suspected for example) that increase risk of a few peculiar varieties of cancer.
> Much evidence is pointing to impaired immune system development > and function as one of the most common mechanisms, i.e., > pesticide exposure does not directly cause the cancer but it > plays a role in disarming/weakening the body's natural > defenses such that tumors gain the upper hand and are able to > progress to become malignant.
I know this is like gospel among green activists, but the evidence doesn't look that strong. I did another lit search on immun* and (pesticide* or phenoxy* or herbicide*). Forty four of these seemed relevant so I downloaded them. Some of those showed immunosuppression in animal studies from high doses of mostly organochlorines, especially pentachlorophenol and chlorophenoxy's (TCDD imurities were implicated). Some organophosphates and carbofuran were implicated, in most studies, at doses higher than farmers are likely to pick up. I could not find any epidemiological evidence of immunosupression among ag workers.
> There is a series of coordinated epidemiological tudies underway > now for 3-5 years as part of a national farm/farm family health > study. Dozens of new studies will be published over the next 24 > months, providing a much firmer base to quantify the contribution > of pesticide exposure (snip)
I would like to follow these reports. Are you going to post links?
> some labelled "junk science" just as the Consumers Union article > and analysis are being attacked.
I'm not familiar with these, but people should be aware that it is possible to design biased studies when you have a political axe to grind.
> Some people in the ag community now so firmly believe that > pesticides are safe, period, that they appear not interested in > nor willing to seriously consider new evidence of risks.
I agree that these risks should be investigated. It is foolish to assume that pesticides are safe, or that all the hazards are understood just because they are registered. But environmental activists need to keep in mind that the level of risk we are talking about here is much less than risk from things like farmers lung, tractor accidents, asthma, PTO accidents, injuries caused by animals, etc. The vast majority of the higher risk of injury and death that farmers experience is clearly caused by factors other than pesticides.
Dale Wilson
Last Updated on 3/7/99
By Karen Lutz
Email: karen@hillnet.com