http://www.cancer.gov/cancertopics/factsheet/Risk/ahs
For example, a study from the AHS reported in 2009 that people who use the weed killer imazethapyr have increased risks of bladder cancer and colon cancer. Imazethapyr is in a class of chemicals known as aromatic amines. It was first used in the United States in 1989, and, since then, has been one of the most commonly used herbicides for killing weeds in soybean, dry bean, alfalfa, and other crop fields.
I explained that pesticide residue on food is not the big concern, the concern is the residue in soil. And it is hardly a significant claim, it is common knowledge for people who work in oncology, however those people have been gagged. You said, "In general pesticides break down over time." Could you please cite where you found that information?
You can see the table for half-life of common pesticides if you click the link below.
http://pmep.cce.cornell.edu/profiles/extoxnet/TIB/movement.html
And the study concludes:
SUMMARY
The release of pesticides into the environment may be followed by a very complex series of events which can transport the pesticide through the air or water, into the ground or even into living organisms. The most important route of distribution and the extent of distribution will be different for each pesticide. It will depend on the formulation of the pesticide (what it is combined with) and how and when it is released. Despite this complexity, it is possible to identify situations that can pose concern and to try to minimize them. However, there are significant gaps in the knowledge of pesticide movement and fate in the environment and so it is best to minimize unnecessary release of pesticides into the environment. The fewer pesticides that are unnecessarily released, the safer our environment will be.
Those gaps in knowledge? Some of them have been paid for.
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