Environmental organic pollutants in human milk before and after weight loss.
Many persistent organic pollutants (POPs) are banned because they accumulate in organisms and are toxic. Lipophilic POPs are stored in maternal adipose tissue and concentrations in human milk (HM) may increase during weight loss. Our aim was to examine associations between weight loss and concentrations of chlorinated POPs in HM in lactating women participating in a weight loss study. We analysed POPs (PCB 28, PCB 153, HCB, DDE) in HM at 12 and 24 weeks postpartum from 32 women who participated in a randomized, 2 × 2 factorial trial of diet and exercise for postpartum weight loss. Participants donated milk before and after the intervention period. We examined associations between weight loss and change in POP concentrations and estimated the intake of POPs by their breastfed infants. Most (n = 27) women lost weight during intervention, 0.45 ± 0.30 kg/week (mean ± SD). Among these women, the concentration of PCB 153 in HM was significantly (p = 0.04) higher at follow-up than at baseline. Weight loss was significantly positively associated with changes in concentrations of all studied POPs (2.0-2.4% increase per percent weight loss). Estimated mean intakes of POPs (ng/day) remained stable because infant milk consumption decreased during the study period. As infants gained weight, estimated mean intakes per kg body weight decreased 17-22%. Changes in concentrations of POPs in HM correlated positively with maternal weight loss, but it is unlikely that the balance between the benefits and risks of breastfeeding will change if the weight loss is restricted to 0.5 kg per week.
Risk Benefit Assessment Department, National Food Agency, PO Box 622, SE-751 26, Uppsala, Sweden. Electronic address: sanna.lignell@slv.se.
Sanna
S
Lignell
Department of Internal Medicine and Clinical Nutrition, University of Gothenburg, PO Box 459, SE-405 30, Gothenburg, Sweden. Electronic address: anna.winkvist@nutrition.gu.se.
Anna
A
Winkvist
Department of Internal Medicine and Clinical Nutrition, University of Gothenburg, PO Box 459, SE-405 30, Gothenburg, Sweden. Electronic address: fredrik.bertz@nutrition.gu.se.
Fredrik
F
Bertz
Division of Nutritional Sciences, Cornell University, Ithaca, NY, 14853, USA. Electronic address: kathleen.rasmussen@cornell.edu.
Kathleen M
KM
Rasmussen
Risk Benefit Assessment Department, National Food Agency, PO Box 622, SE-751 26, Uppsala, Sweden. Electronic address: anders.glynn@slv.se.
Anders
A
Glynn
Chemistry Department, National Food Agency, PO Box 622, SE-751 26, Uppsala, Sweden. Electronic address: marie.aune@slv.se.
Marie
M
Aune
Department of Internal Medicine and Clinical Nutrition, University of Gothenburg, PO Box 459, SE-405 30, Gothenburg, Sweden; Department of Nutrition, Institute of Basic Medical Sciences, University of Oslo, 0317, Oslo, Norway. Electronic address: h.k.brekke@medisin.uio.no.
Hilde Kristin
HK
Brekke
D000328:Adult; D001942:Breast Feeding; D003633:Dichlorodiphenyl Dichloroethylene / Q000032:analysis*; D004785:Environmental Pollutants / Q000032:analysis*; D005081:Exercise Therapy; D005260:Female; D006801:Humans; D007223:Infant; D007774:Lactation; D008895:Milk, Human / Q000737:chemistry*; D050177:Overweight / Q000178:diet therapy / Q000628:therapy; D011078:Polychlorinated Biphenyls / Q000032:analysis*; D015431:Weight Loss
D004785:Environmental Pollutants; D003633:Dichlorodiphenyl Dichloroethylene; D011078:Polychlorinated Biphenyls
Human milk; Obese; Overweight; POPs; Postpartum; Weight loss