Persistent organic pollutants and early menopause in U.S. women.
Level 4 - case-series / case-control
Cross-sectional analysis of survey data
PubMed 25629726 · doi:10.1371/journal.pone.0116057
What was done
Researchers analyzed cross-sectional data from the National Health and Nutrition Examination Survey (NHANES) from 1999 to 2008 (total female pool n = 31,575). Eligible participants were menopausal women older than 30 years who were not pregnant, breastfeeding, using hormonal contraception, or having a history of hysterectomy or bilateral oophorectomy. Serum lipid-adjusted and urine creatinine-adjusted levels of 111 endocrine-disrupting chemicals (EDCs) were analyzed, focusing on chemicals with half-lives >1 year and phthalates. Multivariable linear regression adjusted for age, race/ethnicity, smoking, and body mass index. A secondary analysis evaluated the odds of being menopausal among women aged 45–55 years.
What was found
Fifteen EDCs were significantly associated with earlier menopause: β-hexachlorocyclohexane, mirex, p,p'-DDE, 1,2,3,4,6,7,8-heptachlorodibenzofuran, two phthalates (mono-(2-ethyl-5-hydroxyhexyl) and mono-(2-ethyl-5-oxohexyl) phthalate), and nine polychlorinated biphenyl congeners (-70, -99, -105, -118, -138, -153, -156, -170, -183). Women with high levels had mean menopausal ages 1.9 to 3.8 years earlier than women with lower levels. Among women aged 45–55 years, EDC-exposed women were up to 6 times more likely to be menopausal than non-exposed women.
Why it matters
This study links specific persistent pollutants and phthalates to earlier ovarian senescence in a representative sample of US women, identifying priority chemicals for reproductive toxicity research.
Limits
The cross-sectional design cannot establish causality or exclude reverse causality (such as altered metabolism or excretion of EDCs post-menopause). The exact sample size of the eligible analyzed subset is not stated in the abstract. Single-time-point biomarker measurements were used rather than cumulative lifetime exposure tracking.
Cited by
- supports Endocrine-disrupting chemicals can accelerate the onset of menopause by up to two years.