TY - JOUR
T1 - Influence of maternal bone lead burden and calcium intake on levels of lead in breast milk over the course of lactation
AU - Ettinger, Adrienne S.
AU - Téllez-Rojo, Martha Maria
AU - Amarasiriwardena, Chitra
AU - Peterson, Karen E.
AU - Schwartz, Joel
AU - Aro, Antonio
AU - Hu, Howard
AU - Hernández-Avila, Mauricio
N1 - Funding Information:
This study was supported by grants from the US National Institute of Environmental Health Sciences (P42-ES05947, Superfund Basic Research Program; R01-ES07821; center grant 2 P30-ES 00002; and T32-ES07069 NRSA), by Consejo Nacional de Ciencia y Tecnología (CONACyT) grant 4150M9405, and by CONSERVA, Department of Federal District, México.
PY - 2006/1
Y1 - 2006/1
N2 - The authors studied 367 women who were breastfeeding their infants in Mexico City, Mexico, between 1994 and 1995 to evaluate the effect of cumulative lead exposure, breastfeeding practices, and calcium intake on breast milk lead levels over the course of lactation. Maternal blood and breast milk lead levels were measured at 1, 4, and 7 months postpartum. Bone lead measurements were obtained at 1 month postpartum. At 1, 4, and 7 months postpartum, respectively, the mean breast milk lead levels were 1.4 (standard deviation (SD), 1.1), 1.2 (SD, 1.0), and 0.9 (SD, 0.8) μg/liter and showed a significant decreasing trend over the course of lactation (p < 0.00001). The relations of bone lead and blood lead to breast milk lead were modified by breastfeeding practice, with the highest breast milk lead levels among women with a high level of patella lead who were exclusively breastfeeding. Dietary calcium supplementation increased the rate of decline in breast milk lead by 5-10%, in comparison with a placebo, over the course of lactation, suggesting that calcium supplementation may constitute an important intervention strategy, albeit with a modest effect, for reducing lead in breast milk and thus the potential for exposure by infants.
AB - The authors studied 367 women who were breastfeeding their infants in Mexico City, Mexico, between 1994 and 1995 to evaluate the effect of cumulative lead exposure, breastfeeding practices, and calcium intake on breast milk lead levels over the course of lactation. Maternal blood and breast milk lead levels were measured at 1, 4, and 7 months postpartum. Bone lead measurements were obtained at 1 month postpartum. At 1, 4, and 7 months postpartum, respectively, the mean breast milk lead levels were 1.4 (standard deviation (SD), 1.1), 1.2 (SD, 1.0), and 0.9 (SD, 0.8) μg/liter and showed a significant decreasing trend over the course of lactation (p < 0.00001). The relations of bone lead and blood lead to breast milk lead were modified by breastfeeding practice, with the highest breast milk lead levels among women with a high level of patella lead who were exclusively breastfeeding. Dietary calcium supplementation increased the rate of decline in breast milk lead by 5-10%, in comparison with a placebo, over the course of lactation, suggesting that calcium supplementation may constitute an important intervention strategy, albeit with a modest effect, for reducing lead in breast milk and thus the potential for exposure by infants.
KW - Bone and bones
KW - Breast feeding
KW - Calcium
KW - Lactation
KW - Lead
KW - Longitudinal studies
KW - Milk, human
UR - http://www.scopus.com/inward/record.url?scp=29344459843&partnerID=8YFLogxK
U2 - 10.1093/aje/kwj010
DO - 10.1093/aje/kwj010
M3 - Article
C2 - 16282237
AN - SCOPUS:29344459843
SN - 0002-9262
VL - 163
SP - 48
EP - 56
JO - American Journal of Epidemiology
JF - American Journal of Epidemiology
IS - 1
ER -