Dec. 30 (UPI) -- A new analysis has linked environmental exposure to a certain type of insecticides with increased risk for death from heart disease.
In findings published Monday in the journal JAMA Internal Medicine, researchers report that higher levels of 3-phenoxybenzoic acid in those exposed to pyrethroid-based sprays and other products likely contributes to a roughly 50 percent increase in their risk for death from cardiovascular disease and/or cancer.
Pyrethroids -- which are found in many residential pest control sprays and household and garden insecticides and pet sprays, as well as specialty shampoos, lice treatments and mosquito repellents -- have been used in the United States for more than 40 years.
"Pesticide exposure at varying levels is ubiquitous to the general population," co-author Wei Bao, an assistant professor of epidemiology at the University of Iowa College of Public Health, told UPI. "So the findings have public health relevance to the general population, not only to farmers or pesticide applicators."
Bao and his colleagues assessed the health risks of these products in a study of more than 2,100 adults who participated in the National Health and Nutrition Examination Survey between 1999 and 2002. The participants provided urine samples for pyrethroid metabolite measurements and were linked to mortality data from the survey date through December 31, 2015.
In all, 246 of the study participants died during the follow-up period, and 41 of these deaths were associated with heart disease while 52 were due to cancer-related causes. During the follow-up, 8.5 percent and 10.2 percent of participants with 3-phenoxybenzoic acid levels in their urine between 0.07 and 0.13 ng/mL and 0.14 and 0.49 ng/mL died.
Nearly 12 percent of those with 3-phenoxybenzoic acid levels above 0.50 ng/mL died during the study period.
Although, to date, research attempting to determine "normal" levels of urinary 3-phenoxybenzoic acid has yielded varying results, larger population studies suggest that most people fall within the range of 0.2 to 2 ng/mL. These levels are likely much higher in those who work in occupations in which pyrethroid products are used regularly, like gardening and pest control.
Bao noted that the findings of JAMA Internal Medicine research didn't focus specifically on "occupational exposure," but he offered this advice to all users of these products: "A general recommendation to pesticide applicators is to use appropriate protectors to reduce exposure," he said.