Saturday, May 19, 2012

Understanding Risk

By Rich Kozlovich

Recently I spoke against an anti-pesticide ordinance at the April Cuyahoga County Council meeting in Cleveland, Ohio. The basis for this ordinance was that pesticides were “toxic” and “carcinogenic”. None of that is an explanation for understanding whether they represent an inappropriate ‘risk’ or not, and since those are both trigger words the ordinance was based on scare mongering. One of the council members claimed that they had the studies to show the health risks caused by pesticides. Baloney! If this was true then the EPA would be required by law to remove those products from the market place; and we need to understand that the EPA is not a pesticide friendly organization, but there are even limits to the kind of junk science they can heap on society. However, I do think it is important for everyone to know how risk evaluations are properly done, or in this case an explanation of how they are done improperly.

Statistics aren't science and cannot alone prove the existence or absence of risk. One of the problems with using statistics to determine risk is 'data dredging'. If you drag up enough data you can come up with any explanation that suits the particular issue you are trying to promote. “Statistics are being looked to more and more as explanations for answers to medical problems from people with expertise in mathematical manipulation and information technology, rather than from people with an understanding of disease and its causes." “Statics can’t prove cause and effect associations because they don’t provide biological explanations. Without such explanations, statistical associations are hollow numbers.” Biological explanations, not mere possibilities or conjecture, are a necessary component of determining the existence of risk.

Epidemiology alone isn't science because epidemiology is statistics and alone cannot prove the existence or absence of risk. Mice aren't little people. The results of tests on laboratory animals do not necessarily pertain to humans. Mice aren't little rats either. Very often reactions to a substance that occur in mice do not occur in rats and vice versa. The American Council on Science and Health petitioned the EPA to stop declaring substances ‘carcinogenic’ on rodent testing alone because that violated the principles outlined in the Information Quality Act. “Finally….EPA replied with a dodge, claiming that their Risk Assessment Guidelines are not statements of scientific fact -- and thus not covered by the IQA -- but merely statements of EPA policy.” One would think that policy would be based on science, so if it isn't we must ask; just what is this policy based on? So if the EPA can't find a reason to remove these products from the market place we can be assured some local council has nothing to offer that could ever begin to look like 'valid science'.

Exposure isn't toxicity. Just because someone is exposed to a substance or condition doesn't necessarily mean that they've been exposed to a harmful level. I often read that articles that deal with bio-monitoring to see just how many synthetic chemicals we have in bodies. That number has consistently been over 200. We are also living longer and healthier lives. Does that mean that having more synthetic chemicals in our bodies increases our life span and quality of health? The dose makes the poison. All substances are poisons in sufficient amount. Below that amount, exposures are not harmful. At some point the molecular load of any substance will be so small that cells will not respond to it. This is called the threshold principle.

There is always a safe exposure to a substance or condition.

Sources:
Junk Science Judo, by Steve Milloy
American Council on Science and Health
Ecological Sanity, by Claus and Bolander

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