BPA, a chemical found in everyday plastic items, linked to 49% greater death risk within 10 years: Study
High levels of exposure to a common industrial chemical used in plastic production, Bisphenol A (BPA), has now been associated with an increased risk of death. Researchers found that Americans with higher bisphenol A levels in the urine were about 49% more likely to die during a period of 10 years.
“In a prospective cohort of a US nationally representative sample, we found that BPA exposure was significantly and positively associated with all-cause mortality in adults. The association remained significant after adjustment for demographic characteristics, socioeconomic status, dietary and lifestyle factors, body mass index (BMI), and urinary creatinine levels,” write authors in the study published in JAMA Network Open.
Widespread exposure to bisphenol A has emerged as a major public health concern. BPA belongs to a group of chemicals known as endocrine-disrupting chemicals (EDCs), which are capable of interfering with hormone action and which thereby contribute to disease and disability across the lifespan. Endocrine-disrupting chemicals are found in food and food packaging, water, personal care products, household goods, detergents, fabrics and upholstery, electronics, medical equipment, and pesticides. A recent study said that evidence has doubled in the last five years about the negative impact of endocrine-disrupting chemicals in plastics, pesticides, flame retardants on people’s health.
Bisphenol A is a high-volume industrial chemical produced primarily for the manufacturing of polycarbonate plastics and epoxy resins. According to the US Centers for Disease Control and Prevention (CDC), polycarbonate plastics based on BPA are used in many consumer products, such as plastic bottles, compact discs, plastic dinnerware, impact-resistant safety equipment, automobile parts, and toys. BPA epoxy resins are used in the protective linings of food cans, in dental sealants, and in other products such as thermal paper that is used in sales receipts. In the US currently, 12 states and Washington, DC have restrictions in place against BPA. “Previous epidemiologic studies have shown that BPA exposure is associated with an increased risk of obesity, diabetes, hypertension, and cardiovascular disease. Although growing evidence suggests that BPA has potentially toxic effects on a variety of organs and systems in humans, the association between BPA exposure and risk of mortality remains unknown. In the present study, we examine the association of BPA exposure with all-cause and cause-specific mortality in US adults,” say researchers.
The National Health and Nutrition Examination Survey (NHANES) is a nationally representative health survey program of the resident population in the US. It is administered by the National Center for Health Statistics (NCHS) at the CDC. For the current analysis, the research team included adults aged 20 years or older who participated in NHANES from 2003 to 2008 and had available data on BPA measurements. “We linked all participants to mortality data through 2015, which enabled approximately 10 years of observation for mortality outcomes,” they explain.
Overall, the study included 3,883 adults aged 20 years or older. During “36,514 person-years of follow-up (median 9.6 years, maximum, 13.1 years), 344 deaths occurred, including 71 deaths from cardiovascular disease and 75 deaths from cancer. Participants with greater urinary BPA levels were at higher risk for death. The researchers measured BPA levels in the urine of the US adults and found that participants with higher BPA levels were at a 49% risk of death over the 10 years of observation, even after adjusting for lifestyle factors such as demographics, diet, and BMI. Those with higher levels of BPA were also at more risk of death from heart disease.
Participants with higher urinary BPA levels were more likely to be younger, male, non-Hispanic Black, and have lower educational levels, lower family income, lower physical activity, higher total energy intake, poorer dietary quality, and higher BMI. “After adjustment for age, sex, race/ethnicity, socioeconomic status, dietary and lifestyle factors, BMI, and urinary creatinine levels, the hazard ratio comparing the highest versus the lowest tertile of urinary BPA levels was 1.49 for all-cause mortality, 1.46 for cardiovascular disease mortality, and 0.98 for cancer mortality,” the findings state.
According to the investigators, further studies are needed to replicate the findings in other populations and determine the underlying mechanisms. Given the wide range of potentially toxic effects of BPA in humans, it is imperative and important to minimize human exposure to BPA, they recommend.
Kevin McConway, emeritus professor of applied statistics, The Open University, who did not work on the research, says: “This research used data from quite a large sample of Americans, that is generally representative of the US adult population. But it’s an observational study, and there are always issues in deciding what the results of observational studies actually mean. The big snag is that researchers cannot adjust for everything that might be a confounder. They simply do not have data on all possible confounders.”
Commenting on the findings, Professor Mark L Wahlqvist, emeritus professor and head of Medicine, Monash University and Monash Medical Centre, who also did not work on the paper, says that it “makes it clear, if not surprising, that exposure (to BPA) is reducing survival.” “And bear in mind that the burden of global contamination and pollution with these compounds, along with microplastic and nano plastic on land and in water, especially the oceans, is continuing and has roughly doubled in 10 years. There is now virtually no form of sea life which is free of endocrine disruptors, with the particles binding about five times the amount because of their peculiar binding sites,” he says.