Levels of Octachlorostyrene in Mothers’ Milk and Potential Exposure Among Infants in Sendai City, Japan 2012

Persistent organic pollutants can accumulate inside the human body, including in mothers’ milk, which may affect infant development. This cross-sectional study aimed to examine selected persistent organic pollutants in the milk of 100 mothers in Sendai city, Miyagi Prefecture, Japan. We used gas-chromatography-electron capture negative chemical ionization-mass spectrometry to check for octachlorostyrene, dechlorane (Dec) plus, Dec 602, Dec 603, and Dec 604. Octachlorostyrene was detected in 86 samples at more than the method detection limit (84 pg g-lipid(−1)) but no dechloranes were above the method detection limit (1 ng mL(−1) for dechlorane plus, Dec 602, and Dec 603; 20 ng mL(−1) for Dec 604). The mean octachlorostyrene concentration was 461 pg g-lipid(−1), the median was 337 pg g-lipid(−1), and the standard deviation 450 pg g-lipid(−1). No baseline characteristics were associated with octachlorostyrene level except for mother’s occupation (stay-at-home mother, 353 ± 327 pg g-lipid(−1); others, 531 ± 509 pg g-lipid(−1)). Octachlorostyrene was also significantly negatively correlated with lipid content (r = −0.35, p = 0.0004). However, the maximum intake of octachlorostyrene among infants in this study (3.5 ng/kg/day) was under the acceptable daily intake (30 ng/kg/day, derived from 12−month study in rats), and is therefore unlikely to pose a health risk.