There are a variety of ways to rid insects from your home: plugging structural holes, strategically placing poisons, or adopting a cat. Whichever method you chose, you have to consider any potential risks the method has for your health.
Pyrethroids are insecticides included in over 3,500 registered products, many of which are used widely in and around households, including on pets and in treated clothing, in mosquito control, and in agriculture.
Source: EPA Pyrethrins and Pyrethroids
According to the EPA, the general US population is commonly exposed to pyrethroids like permethrin and cypermethrin. Exposure can occur through inhalation, ingestion, or even skin absorption.
To measure this pest control substance in the body, scientists use a biomarker called 3-PBA. This biomarker can tell scientists not only if exposure is present, but if the exposure is high or low.
Risk of heart disease
Source: Nonoccupational Exposure to Pyrethroids and Risk of Coronary Heart Disease in the Chinese Population
To measure the association between pest control exposure and heart disease, researchers in the Shanxi province of China recruited 72 heart disease patients and 136 healthy patients matched by age and gender. Participants with a family history of heart disease, adverse medical history, and occupational chemical exposures were excluded. The presence of heart disease was correlated with results from urine sample testing for pest control exposure.
A positive association was found between participants with the highest levels of pyrethroids exposure and the risk of heart disease. However, we do not know exactly how severe the relationship is because the confidence interval is wide.
Risk of death
Source: Association Between Exposure to Pyrethroid Insecticides and Risk of All-Cause and Cause-Specific Mortality in the General US Adult Population
To measure the association between pest control exposure and mortality, researchers in the United States used data from a well-known survey called NHANES. They used a sample of 2116 adults, aged 20 years and older, with a mean age of 42.6 years.
They followed the participants for an average of 14.4 years. Over the study period, 246 deaths were reported. The researchers analyzed participant urine samples and correlated their results to mortality reports.
Researchers found a positive association between pest control exposure and increased risk of both all-cause mortality and heart disease mortality. Cancer mortality was not found to be significant.
Interestingly, a few demographic characteristics were associated with high pest control exposure risk: non-Hispanic black, lower educational levels, lower family incomes, and poorer dietary quality. The correlation between pest control exposure and all-cause mortality was also 5.69 times higher among participants with obesity.
There are a number of potential explanations for these associations. We must consider location, occupation, and other socioeconomic factors as potential avenues for exposure. For example, participants with a lower income may live in areas with poorer regulation of hazardous chemicals.
What does this all mean?
The data suggest that high levels of exposure to pest control products containing pyrethroids may be associated with an increased risk of heart disease, heart disease mortality, and all-cause mortality. However, these studies did not completely isolate pyrethroid chemicals from all the other chemicals that could be influencing health outcomes. In general, the average study participant had relatively low levels of pest control exposure.