3D model of dichlorodiphenyltrichloroethane (DDT), an insecticide
I think everyone would agree that it would not be a good idea to put pesticides in a saltshaker and add them to our food at the table. But there is little agreement when it comes to their use in agriculture. How much gets into our food? What are the effects on our health? On the environment? Is there a safer alternative?
Where should we look to find science-based answers to those questions? One place we should not look is books written by biased non-scientists to advance their personal agendas. A friend recently sent me a prime example of such a book: Myths of Safe Pesticides, by André Leu, an organic farmer whose opinions preceded his research and whose bias is revealed in the very title. (more…)
Three kids on the same block were diagnosed with leukemia last year. That couldn’t happen just by chance, could it? There MUST be something in the environment that caused it (power lines, the chemical plant down the street, asbestos in their school, iPods, Twinkies?). Quick, let’s measure everything we can think of and compare exposures to other blocks and find an explanation.
That may be the common reaction, and it may seem plausible to the general public, but it’s not good science.
I have just read a book that does a great job of elucidating the pitfalls of epidemiologic studies, the problematic interface between science and emotion-laden public concerns, and the way environmental hazards have been hyped far beyond the evidence. Hyping Health Risks: Environmental Hazards in Daily Life and the Science of Epidemiology by Geoffrey C. Kabat.
He covers the uses, strengths and limitations of epidemiology, discusses the pros and cons of different study designs, and explains how to judge whether an association is causal.
One-fourth of the veterans of the 1990-91 Gulf War complain of persistent memory and concentration problems, chronic headaches, widespread pain, gastrointestinal problems, and other chronic abnormalities not explained by well-established diagnoses. Treatments are ineffective and symptoms do not improve over time. Gulf War Syndrome or Gulf War Illness is a controversial diagnosis, and some have questioned whether it really exists. Now a new report from the Research Advisory Committee on Gulf War Veterans’ Illnesses has concluded that Gulf War Illness is real and that it is probably attributable to pyridostigmine bromide (PB) and pesticide exposures.
Its major conclusions:
- Gulf War illness is a serious condition that affects at least one fourth of the 697,000 U.S. veterans who served in the 1990-1991 Gulf War.
- Gulf War illness fundamentally differs from trauma and stress-related syndromes described after other wars.
- Evidence strongly and consistently indicates that two Gulf War neurotoxic exposures are causally associated with Gulf War illness: 1) use of pyridostigmine bromide (PB) pills, given to protect troops from effects of nerve agents, and 2) pesticide use during deployment.
The Research Advisory Committee on Gulf War Veterans’ Illnesses was mandated by Congress and appointed in 2002. The report, published November 17, 2008, is an exhaustive review of all available data, including some that is unpublished. It runs to 454 pages, has multiple authors and consultants, lists 1840 references and has multiple appendices. I can’t pretend to have mastered all the information, but I have read enough to understand the basis of their conclusions. They are based on good evidence and logic, but they leave me with some doubts.