And there have been many incidents of serious poisonings, even deaths, from exposure to pesticides used legally and according to label directions. There are serious concerns with relying on the current pesticide regulatory process as sufficient to protect the public from potential health effects of pesticides especially chronic effects such as cancer, and damage to the brain and reproductive systems. I wish to focus on four of the more important weaknesses. The scientific tests that are required to register pesticides are based on regulations passed over twenty years ago and apply only to gross toxicological endpoints. The recent concern with endocrine disrupters and sperm counts is an example of these developments.
Current regulations require only one chemical to be tested at a time.
Often it may take a very high dose of the chemical to produce a toxic effect. This ignores synergistic or multiplicative effects from exposure to more than one chemical at a time which is the usual situation with human exposures. Recent studies show that when exposure occurs to two or more chemicals at the same time, very low doses can produce a toxic effect. This has enormous implications for pesticides since most are mixtures, including unknown inert ingredients, and common practice is to use a variety of pesticides including herbicides, insecticides, and fungicides. Current regulatory requirements do not include studies of or consider exposures to vulnerable populations.