(NaturalNews) A recent study conducted by researchers from the University of Texas at Austin has uncovered evidence that the damage done by pesticides may last for four generations or more.
Reproductive neuroendocrinologist Andrea Gore and evolutionary biologist David Crews compared the sexual behavior of two different groups of rats. One group of rats was a standard laboratory rat stock, while the other group was descended from rats that had been subjected to the hormone-disrupting effects of chemicals. Reproductive biologist had injected the great-grandmothers of these rats with vinclozolin, a common fungicide that is particularly popular among grape-growers.
Skinner’s research had previously shown that the male descendents of the rats who had been injected with vinclozolin developed various reproductive and other difficulties later in life, including sperm deficiencies, infertility, breast tumors and kidney disease.
All the rats in the Gore-Crews study were between 90 and 120 years old, half were female and half were male. Males and females were separated by a wire mesh, and then the researchers timed how long each rat spent sniffing or bumping noses with rats of the opposite sex, indicators of sexual interest.
The researchers observed no difference in how female rats were treated by males, regardless of whether those females were descended of injected rats or control rats. But females expressed significantly less interest in males who were descended of vinclozolin-injected rats than in males descended from control rats.
Researchers could not find any apparent health or fertility problems in the rats descended of the injected females. This led them to believe that certain chemicals function not to damage DNA, but instead to permanently silence or reprogram normal genes to have abnormal function. This type of change can be more long-lasting than a mutation, which can be more easily bred out of a population through mating with healthy animals.
Because the reproductive developmental processes of mammals are all incredibly similar to each other, the researchers believe that similar effects probably occur in humans exposed to toxic chemicals as well.
Friday, June 20, 2008
by: David Gutierrez
Source: Natural News