New research from the University of Iowa shows that people with higher levels of a certain chemical in their bodies, indicating exposure to commonly used pesticides, are significantly more likely to die from cardiovascular disease.
The results, published in JAMA Internal Medicine, show that people with high exposure to pyrethroid pesticides are three times less likely to die from cardiovascular disease than people with low or no exposure to pyrethroid pesticides.
The results come from an analysis of a nationally representative sample of U.S. adults, not just those who work in agriculture, said Wei Bao, an assistant professor of epidemiology at the University of Iowa School of Public Health and an author of the study. This means that the findings have public health implications for the general population.
He also cautioned that because this is an observational study, it cannot determine whether people in the sample died as a result of direct exposure to pyrethroids. The results suggest a high likelihood of a link, but more research is needed to replicate the results and determine the biological mechanism, he said.
Pyrethroids are among the most commonly used insecticides by market share, accounting for the majority of commercial household insecticides. They are found in many commercial brands of insecticides and are widely used for pest control in agricultural, public and residential settings. Metabolites of pyrethroids, such as 3-phenoxybenzoic acid, can be found in the urine of people exposed to pyrethroids.
Bao and his research team analyzed data on 3-phenoxybenzoic acid levels in urine samples from 2,116 adults aged 20 years and older who participated in the National Health and Nutrition Examination Survey between 1999 and 2002. They collated mortality data to determine how many adults in their data sample had died by 2015 and why.
They found that over an average follow-up period of 14 years, by 2015, people with the highest levels of 3-phenoxybenzoic acid in urine samples were 56 percent more likely to die from any cause than people with the lowest levels of exposure. Cardiovascular disease, by far the leading cause of death, is three times more likely.
Although Bao’s study did not determine how subjects were exposed to pyrethroids, he said previous studies have shown that most pyrethroid exposure occurs through food, as people who eat fruits and vegetables sprayed with pyrethroids ingest the chemical. The use of pyrethroids for pest control in gardens and homes is also an important source of infestation. Pyrethroids are also present in household dust where these pesticides are used.
Bao noted that the market share of pyrethroid insecticides has increased since the 1999-2002 study period, making it likely that cardiovascular mortality associated with their exposure has also increased. However, further research is needed to evaluate whether this hypothesis is correct, Bao said.
The paper, “Association of exposure to pyrethroid insecticides and the risk of all-cause and cause-specific mortality among US adults,” was co-authored by Buyun Liu and Hans-Joachim Lemler of the University of Illinois School of Public Health. , along with Derek Simonson, a graduate student at the University of Illinois in human toxicology. Published in the December 30, 2019 issue of JAMA Internal Medicine.
Post time: Mar-15-2024