A group of specialists from the Juarez University of the State of Durango (UJED) has discovered traces of organochlorine pesticides in the blood of children and pregnant women in the Laguna region. Said pesticides were applied three, four, and even five decades ago.
Édgar Olivas, chief investigator from the UJED
, explained that his team had conducted a study on 60 pregnant women and 60 children born in 2017 in the communities of La Laguna and Durango, and found that they all had concentrations of pesticides such as DDT , which is a colorless, tasteless, and almost odorless crystalline chemical compound.
“They were all evaluated and we found pesticide concentrations. In some cases, they were minimal amounts, but we cannot assure that they are harmless,” the specialist explained.
The study showed that some mothers had DDT concentrations of 24 nanograms per millimeter while newborns showed concentrations of up to 30 nanograms. The scientists also found endosulfan concentrations of 13 nanograms in the mothers and 20 among babies, as well as methoxychlor concentrations of up to 70 nanograms in mothers and 55 nanograms in newborn babies.
“It’s too much, these chemicals should not be found in newborns at all,” claimed the investigator Édgar Olivas. Each test subject was found to have concentrations of between five and seven different organochlorines. “This is quite significant. The presence of DDT is certainly the most concerning,” he added.
Said pesticides were applied at a time when the cultivation of cotton was booming in the region, which extended across 247,105 acres . However, they still persist in the environment. “Perhaps now the amounts are minimal, but it still poses a threat to public health,” argued Olivas.
Mario García Carrillo
, an investigator from the soil department at the Antonio Narro Autonomous Agrarian University (UAAAN) , reminded that back then, when said pesticides were broadly used for pest control, farmers would conduct between 10 and 15 pesticide applications per farming cycle, which could be the cause of their persistence on soil.
"The soil tends to absorb that sort of compound and hold it for decades, I’d say for up to 50 years,” García Carrillo explained.
Though many of those pesticides were banned in the 1970s and 80s, other organochlorine products such as endosulfan are still used frequently in the country.
The UAAAN investigator has conducted several studies on soil, where he found residues of pesticides such as DDT. He added that pesticides do not exist in nature, but are completely synthetic. Perhaps at the time they offered many advantages for agricultural crops since they helped eliminate pests. “But the thing is that once the DDT is applied, it decomposes into metabolites, which are more persistent, stable, and dangerous than the original substance,” he warned.
“The problem,” added Mario García, “is that the residues don’t stay in the same place. They tend to move towards water bodies such as dams or aquifers.”
Édgar Olivas mentioned that organochlorine contamination in the bloodstream is known to cause to neurodevelopmental deficits in newborns. He explained that organochlorinated pesticides tended to accumulate in parts of the body that are high in fat, such as the brain. This puts babies at risk of developing learning disabilities at school or other cognitive issues.
Édgar Olivas passed on the results of his investigation to the Sanitary Jurisdiction of Gómez Palacio , in the Mexican state of Durango.
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