Pesticide exposure robs Yaqui girls of breastfeeding.
Posted Feb 21 2010 12:00am
Pesticide exposure robs Yaqui girls of breastfeeding. by Terri C. Hansen - Environment and Science Reporter
SONORA VALLEY, Mexico—The problems began ominously with the Yaqui pueblo peoples after they accepted pesticide practices in the 1950s so-called Green Revolution.
The intensive industrial agricultural pesticide approach was born in the Yaqui homeland in the northwestern Mexican state of Sonora’s Yaqui Valley.
The decision whether to accept pesticides divided the poverty-stricken Yaqui community.
The valley Yaqui agreed to grow wheat treated with pesticides for export and for other purposes. The other Yaqui removed themselves to the foothills, avoiding pesticide use or exposure.
Long-term research led by Elizabeth Guillette, Ph.D., of the University of Florida found compelling proof that pesticides acted as endocrine disruptors and produced negative health impacts over the years to the exposed Yaqui indigenous communities.
Endocrine disruptors or EDCs, endocrine disrupting chemicals, include chemicals DDT and other pesticides.
Guillette’s latest research finds that some pre-adolescent daughters of mothers exposed to pesticide spraying will never have the ability to breast-feed their babies. With others there is uncertainly. Although there is breast growth some daughters lacked development of the mammary tissue needed to produce milk, or developed a minimal amount.
As the girls in the exposed group matured their breast size became much larger than normal, yet they had less mammary tissue and often none at all, while the unexposed girls were normal.
“A large study, using my techniques, was done in India showing the exact same results,” says Guillette. She published her research findings in the journal Environmental Health Perspectives.
Other EDCs include Bisphenol A or BPA used in many plastic products and dental sealants, and PCBs. EDCs interfere with the hormones that send signals to the nervous system, reproductive system, kidneys, gut, liver and fat.
Human and experimental animal studies clearly show that exposure to certain EDCs before birth can harm the development of the nervous system, neuroendocrine function, and behavior, said Guillette.
Population studies that show the age that puberty occurs is becoming younger have raised concerns about the influence of EDCs on the rise in precocious puberty.
There is a growing body of evidence that EDCs lower testosterone levels, reduce sperm count, and cause malformations of male sex organs. Evidence in regions and countries where far fewer boys than girls are being born link skewed sex ratios with unidentified external influences and suggest EDCs are involved.
Guillette said her study proves pesticide exposures can cross generations and that they have affected the daughters of mothers exposed to agricultural pesticides. “The results underscore the importance of women protecting themselves from manufactured chemicals beginning at birth because they stay in the body.”
“Some of the most devastating injustices [are] visited on indigenous farming communities around the world,” stated the Pesticide Action Network. “High exposure to pesticides suffered by many indigenous peoples is a frequent indicator of these injustices.”
What piqued Guillette’s interest was Dr. Theo Colborn’s research that brought widespread attention to hormonal changes wrought to wildlife and humans by EDCs. An anthropologist referred her to the Sonoma Yaqui Valley, where research was promising with two groups virtually identical except for their exposures to pesticides.
Study results from her first long-term study, published in the journal EHP in 1999 in which she tested Yaqui children aged four and five indicated key differences between the two populations in fine motor skills such as hand-eye coordination, balance, short-term memory, simple problem solving and even the ability to draw a human figure.
“The future of our society depends on today’s children,” said Guillette. “Preventative action to protect them from contamination must occur now, including individual, national and global levels.”