Precaution on Toxics in an Interlocked World

In “ ‘Better Safe Than Sorry’ Carries a High Price Tag” (Commentary, June 21), Henry Miller argues against the “precautionary principle,” stating that, for instance, many more lives were lost by the banning of DDT and a consequent spread of malaria than would have been if we had continued to use DDT as a pesticide.

Actually, by the time Paul Muller, the inventor of DDT, received the Nobel Prize in 1948 there were already reports of the evolution of resistance to DDT by houseflies. By 1960, mosquitoes had effectively evolved a resistance to the chemical. As Stephen Palumbi reported in an article in the Sept. 7, 2001, issue of the journal Science, more than 500 species had evolved resistance to at least one pesticide by 1990.

The idea that the world can be treated categorically, rather than needing to be taken evolutionarily, is seductive but ultimately more dangerous by far than the idea Miller makes objection to--the precautionary principle.

Ashwani Vasishth

Hollywood

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Human history is fraught with problematic episodes of leaping into things before discovering all the consequences. Although DDT is effective in stopping the spread of malaria, it is one of the most deadly chemicals ever to have seen the commercial market. The large DDT deposit off the Palos Verdes coast necessitates a Superfund cleanup, has devastated an ecosystem and harmed people eating contaminated fish. DDT has done similar things elsewhere. Toxic chemicals don’t go away. Following the precautionary principle would have been handy in the case of nuclear power. The previous generation has created dependency on a system that produces tons of deadly waste that outlives us all by tens of thousands of years. The scientific method only speaks for that which scientists are able to directly and repeatedly observe. Lack of studies demonstrating harm does not mean there is no harm occurring.

Andrea L. Bell

Long Beach