According to researchers from the Harvard School of Public Health, chemicals found in food packaging can lower a child’s response to immunizations.

Perfluorinated compounds can be found in grease-resistant packaging like popcorn bags and pizza boxes. They are also in Teflon products including non-stick cooking pans and cleaning and personal-care products like shampoo, dental floss, and denture cleaners.

"These findings suggest a decreased effect of childhood vaccines and may reflect a more general immune system deficit,” said Philippe Grandjean, M.D., D.M.Sc. “Assessment of risk related to exposure to these contaminants therefore needs to consider the immunotoxic potential of the PFCs."

Dr. Grandjean’s team studied 656 children born during 1999-2001 for seven years, measuring serum antibody concentrations against tetanus and diphtheria.

The study is published in the Journal of the American Medical Association.