Is Common Pesticide Responsible for Rare Birth Defect?
In 2007, Indiana researchers reported in the Journal of Pediatric Surgery that high levels of atrazine were linked to the state’s equally high number of birth defects, particularly gastroschisis. The research used data from the Centers for Disease Control and the Indiana State Department of Health.
Gastroschisis is a birth defect in which the infant is born with some or all of its intestines protruding through an opening in the abdominal wall that never closed, as during typical fetal development. The defect is often corrected through surgery, though often the procedure cannot happen right away as the intestines are too swollen to be reinserted. Up to ten percent of the children born this way do not survive.
A rare occurrence in the past, happening to 1 in 5,000 babies born, gastroschisis has been on the rise in the U.S. and around the world. Nobody seems to know why, but there is at least one strong theory.
Atrazine is an herbicide applied to corn, sorghum, and sugarcane, among other crops. It’s also applied to sod, pasture, Christmas trees, and woody ornamentals. Introduced in 1958, atrazine is a product of Syngenta, which claims it is “still one of the most effective, affordable and trusted products in agriculture today”.
A study published in 2009 in Acta Paediatrica, found results similar to that of the Indiana study, this time for the general U.S. population. Atrazine, the study found, increased the risk of nine birth defects in babies born to mothers who conceived in late spring/early summer, the period when atrazine surface water levels are highest.
Later in 2009, the Natural Resources Defense Council asked the U.S. EPA to restrict the use of atrazine, citing numerous health threats. Banned in the E.U. in 2004 because of its persistence in groundwater contamination, atrazine is a known hormone-disruptor that can interfere with the body’s hormonal activity and development of the reproductive system. The EPA declined NRDC’s request.
The latest study was done by the University of Washington in 2010. Researchers there were alerted to high levels of gastroschisis in that state, double the levels of everywhere else in the country. The study included all live births of infants with the birth defect from 1987-2006. Birth certificates were matched with U.S. Geological Survey databases of agricultural spraying.
The results showed more frequency in the defect among infants whose mothers lived less than 25 km from the site of high surface water contamination with atrazine. The risk was also greater for babies conceived in spring (March-May), when chemical use was more prevalent.
Syngenta dismissed the findings as “not credible”, claiming a large number of studies have shown no birth defects. It also referred to its consistent approval by the EPA.
The EPA allows for 3 parts per billion of atrazine in U.S. drinking water. As NRDC pointed out in 2009, however, the EPA looks at annual average levels, which misses springtime spikes. Bi-weekly data collected by the EPA from 139 municipal water systems found atrazine present 90% of the time, and 54 systems had one-time spikes above the recommend safety level.
For mothers in the critical, early stages of pregnancy, even very low levels of a hormone disruptor can cause birth defects.
This is perhaps most poignant and painful for the mothers in the small community on the Queensland/New South Wales border of Australia. In the past three years, there have been at least seven babies born with gastrochisis, which could bring birth data for the defect there to 1 in 950 births, an astoundingly high number. While health officials there scramble to figure out what’s going on in this area, surrounded by farmland treated with atrazine, parents wait and deal with guilt.
In the past, gastroschisis has been blamed on mothers who smoked or took recreational drugs during pregnancy. Mothers in Queensland, however, who took part in neither activity, want answers.
See more on the story: Cluster of Rare Birth Defects in Small Community