Even though the levels of two environmental pollutants have declined over the last 20 years, they may still have adverse effects on children's development, according to a new study by the Norwegian Institute of Public Health. This is the largest study of environmental pollutants and infant growth to date.
Researchers investigated whether exposure to two persistent organic pollutants before and after birth was associated with rapid growth in infancy, a known risk factor for obesity in later life:
- polychlorinated biphenyl 153 (PCB153), a chemical used extensively in windows and electrical equipment in Norway before being banned in the 1990s
- p,p'-dichlorodiphenyldichloroethylene (p,p'-DDE), a metabolite of the controversial pesticide 1,1,1-trichloro-2,2-bis(4-chlorophenyl)ethane (p,p′-DDT), now only used in malaria control
Due to their long half-lives, these pollutants accumulate and become concentrated in the food chain. Humans are exposed to them through food, particularly seafood and breast milk.
Affects growth
The researchers found that maternal levels of DDE (indicating the levels to which the foetuses were exposed to in utero) were significantly associated with rapid growth in early life. They also found that levels of PCB153 in milk and the amount transferred through breastfeeding were associated with decreased infant growth and falling below expected growth curves.
"Although PCB and DDE levels have declined markedly over the last 20 years, our study shows that even the lower levels that European infants are exposed to today may affect their development. This is important information for regulatory bodies, and emphasises the need to continue to reduce these pollutants in the environment," says Merete Eggesbø, Principal Investigator of the HUMIS cohort study at the Norwegian Institute of Public Health.
"We also need to identify any unwanted effects from pollutants transferred through breast milk so we can establish optimal breastfeeding recommendations," she adds.
http://www.fhi.no/artikler/?id=114260