Higher concentrations in children associated with lower antibodies against diphtheria, tetanus
MONDAY, June 21 (HealthDay News) -- Exposure to polychlorinated biphenyls (PCBs) early in life may reduce the effectiveness of childhood vaccinations and impair immune-system responses to infection, according to research published online June 20 in Environmental Health Perspectives.
Carsten Heilmann, M.D., of the Copenhagen University Hospital in Denmark, and colleagues analyzed data from 587 children residing in the Faroe Islands who were born between 1999 and 2001. Mothers provided blood samples at 32 weeks of pregnancy, as well as samples of milk four to five days after birth. Children were vaccinated against diphtheria and tetanus, and blood samples were taken from them periodically.
The researchers found that higher PCB concentrations, especially in children at 18 months, were linked to lower concentrations of antibodies against diphtheria and tetanus at 5 and 7 years of age. In some children, antibody concentrations were insufficient to protect against the diseases.
"Developmental PCB exposure is associated with immunotoxic effects on serum concentrations of specific antibodies against diphtheria and tetanus vaccinations. The immune system development during the first years of life appears to be particularly vulnerable to this exposure," the authors conclude.