(Beyond Pesticides, July 28, 2014) New research from Michael Skinner, Ph.D.â€™s laboratory out of Washington State University finds that â€“yet againâ€” exposure to pesticides may have devastating consequences for future generations. The study, â€śPesticide Methoxychlor Promotes the Epigenetic Transgenerational Inheritance of Adult-Onset Disease through the Female Germline,â€ť published in PLOS ONE, finds that gestating rats exposed to the pesticide methoxychlor develop a higher incidence of kidney disease, ovary disease and obesity in offspring spanning three generations. The incidence of multiple diseases increased in the third generation or “great-grandchildren.”
This study suggests that ancestral exposures to methoxychlor over the past 50 years in North America may play a part in today’s increasing rates of obesity and disease. The epigenetic changes observed were specific to methoxychlor exposure and, according to researchers, may prove to be valuable biomarkers for future research on transgenerational disease. For people exposed to the pesticide, Dr. Skinner says his findings have implications such as reduced fertility, increased adult onset disease and the potential to pass on those conditions to subsequent generations.
“What your great-grandmother was exposed to during pregnancy, like the pesticide methoxychlor, may promote a dramatic increase in your susceptibility to develop disease, and you will pass this on to your grandchildren in the absence of any continued exposures,” says Dr. Skinner.
Methoxychlor is an organochlorine compound which, though eventually cancelled in 2003 in the U.S., was initially developed as a â€śsaferâ€ť replacement to DDT. It was first registered in 1948, and has been used to control various nuisance species including cockroaches, mosquitoes, flies and chiggers, as well as various arthropods that attack field crops, vegetables, fruits, ornamentals, stored grain, livestock, and domestic pets. Methoxychlor can behave like the hormone estrogen and profoundly affects the reproductive system. It is also listed as a persistent, bioaccumulative, and toxic (PBT) chemical by the EPA Toxics Release Inventory (TRI) program. PBT chemicals are of particular concern not only because they are toxic, but also because they remain in the environment for long periods of time, are not readily destroyed, and build up or accumulate in body tissue.
Previous studies have demonstrated that exposure to chemicals, including fungicides, dioxins, and other endocrine disruptors, can have severe health impacts on offspring. This study builds on a history of research showing that pesticides â€“even a decade after it is bannedâ€” can continue to impact health across generations. Evidence of multi-generational impacts from pesticide exposure is not isolated to laboratory animals. A 2007 scholarly review, entitled Pesticides, Sexual Development, Reproduction and Fertility: Current Perspective and Future Direction, written by Theo Colborn, PhD. and Lynn Carroll, PhD, points to studies linking the legacy chemical DDT to transgenerational health effects.
Dr. Skinner, who has been studying the genetic effects of pesticides for 15 years, and was dubbed â€śThe Epigenetic Hereticâ€ť by Science Magazine, is also the author of the landmark study that links exposure to the insecticide DDT with multi-generational effects. The 2013 study, â€śAncestral dichlorodiphenyltrichloroethane (DDT) exposure promotes epigenetic transgenerational inheritance of obesity,â€ť finds that, while the first generation of ratsâ€™ offspring develop severe health problems, more than half of the rats studied areÂ likely to be obese by the third generation.
In addition to these two important studies, Dr. Skinner’s lab has also documented epigenetic effects from a host of other environmental toxicants, including plastics, pesticides, fungicides, dioxins, hydrocarbons and the plasticizer bisphenol-A or BPA. He has published over 240 peer-reviewed publications and has been to an equal amount of invited symposia, plenary lectures and university seminars, including Beyond Pesticidesâ€™ annual forum. The newest findings support those observations.
For more information, watch Dr. Skinner’s most recent talk, Epigenetic Transgenerational Actions of Endocrine Disruptors on Reproduction and Disease: The Ghosts in Your Genes, Â from Beyond Pesticides’ 32nd National Pesticide Forum in Portland, OR, April 2014.
Source: WSU News
All unattributed positions and opinions in this piece are those of Beyond Pesticides.