How was the review conducted?

Scientists at the National Cancer Institute and the National Institute for Environmental Health Science conducted the review. They looked only at "epidemiologic" studies, those that study people exposed to pesticides at work or elsewhere; studies of laboratory animals were not included. They included studies of various kinds of cancer, nervous system problems associated with chronic low-level exposure, and nervous system diseases like Parkinson's disease and dementia. In all, over 300 studies were included in the review.

What did the review find?

The review found, for the cancers non-Hodgkin's lymphoma, leukemia, and prostate cancer, that the majority of studies demonstrated a link between pesticide use and cancer. In addition, studies show that chronic low-level pesticide exposure is associated with a broad range of nervous system symptoms: headache, fatigue, dizziness, tension, anger, depression, and impaired memory, Parkinson's disease, and Alzheimer's disease. The review concludes that "human health effects occur at current exposure levels in occupational and environmental settings." The review also concludes that epidemiologic studies, like those included in this review, "will allow the human health risks of pesticide exposure to be more accurately judged by the makers of public health policy."

View abstract of this review article:
http://arjournals.annualreviews.org/doi/abs/10.1146/annurev.publhealth.25.101802.123020