Circulating serum xenoestrogens and mammographic breast density.

Introduction: Humans are widely exposed to estrogenically active phthalates, parabens, and phenols, raising concerns about potential effects on breast tissue and breast cancer risk. We sought to determine the association of circulating serum levels of these chemicals (reflecting recent exposure) with mammographic breast density (a marker of breast cancer risk).

Methods: We recruited postmenopausal women aged 55 to 70 years from mammography clinics in Madison, Wisconsin (N = 264).