Determinants of Polychlorinated Biphenyl Levels in Plasma from 42-Month-Old Children

Abstract.

We report on the PCB levels in plasma from 42-month-old children and the factors that determine these levels. We measured the levels of the PCB congeners 118 (2,4,5-3′4′ pentachlorobiphenyl (CB)), 138 (2,3,4-2′4′5′hexaCB), 153 (2,4,5-2′4′5′hexaCB), and 180 (2,3,4,5-2′4′5′heptaCB) in cord plasma, breast milk, and plasma from 42-month-old children (n = 126) living in the Groningen area, The Netherlands. The sum of the levels of these four congeners was calculated for cord plasma (ΣPCB_cord), breast milk (ΣPCB_milk), and 42-month plasma (ΣPCB_42mo). ΣPCB_cord was used as a measure of prenatal exposure. Postnatal exposure was assessed in terms of the ΣPCB_milk and the duration of lactation. In addition, maternal factors including age, body weight and height, parity, and formal education were recorded. In 42-month-old children who have been fully breast-fed for at least six weeks as babies, the median ΣPCB_42mo was 4.5 times as high as that in formula-fed children (0.81 μg/L vs. 0.18 μg/L). The PCB levels in cord blood and human milk and the duration of breast-feeding predict the plasma PCB level at 42 months. Each additional week of full breast-feeding is estimated to result in an increase of 0.3% of the milk PCB level. We concluded that lactation is a major source for the child's PCB body burden at 42 months.