Adults and young boys exposed to high levels of phthalates have reduced levels of testosterone in their blood, a new study finds.
Phthalate is a chemical that's commonly found in plastic and some personal care products. It is known to have many negative effects on a person's mental and physical health. In a new study by researchers from the University of Michigan, it was found that adults and young boys exposed to high levels of phthalates have reduced levels of testosterone in their blood compared to those with lower exposure to the chemical.
"We found that reduced levels of circulating testosterone were associated with increased phthalate exposure in several key populations, including boys ages 6-12, and men and women ages 40-60," said John Meeker, associate professor of environmental health science at the U-M School of Public Health, in a press statement. "This may have important public health implications, since low testosterone levels in young boys can negatively impact reproductive development, and in middle age can impair sexual function, libido, energy, cognitive function and bone health in men and women.
The study was conducted on 2,208 people who participated in the U.S. National Health and Nutrition Examination Survey, 2011-2012. Study authors measured their phthalate exposure and testosterone levels. They also analyzed urine samples to measure concentrations of 13 substances left after the body metabolizes phthalates. Each participant's testosterone level was measured using a blood sample.
Researchers noted that among boys aged between 6 and 12 years, increased concentrations of metabolites of a phthalate called di-(2-ethylhexyl) phthalate resulted in a 24 to 34.1 percent drop in testosterones levels. For women aged between 40 to 60 years, the drop was between 10.8 and 24 percent.
"While the study's cross-sectional design limit the conclusions we can draw, our results support the hypothesis that environmental exposure to endocrine-disrupting chemicals such as phthalates could be contributing to the trend of declining testosterone and related disorders," Meeker said. "With mounting evidence for adverse health effects, individuals and policymakers alike may want to take steps to limit human exposure to the degree possible."
Previous studies on animals have also found that phthalates block the effects of testosterone on the body's organs and tissues. Findings were published online in the Journal of Clinical Endocrinology & Metabolism.
