By Ben Harder
Men’s exposure to some compounds common in cosmetics and plastics is associated with sperm abnormalities, a new study suggests. The data don’t establish a causative link between so-called phthalates and aberrant semen, but they bolster the case that phthalate concentrations typically seen in healthy people may have a negative effect on male reproduction.
Scientists have been working for years to understand the causes in developed countries of an apparent half-century-long decline in sperm quality–lower counts, reduced motility, and higher fractions appearing malformed. One hypothesis attributes this trend to the increasing prevalence of certain hormonally active chemicals, including phthalates, in the environment and in people’s bodies.