Household chemicals can make vaccines less effective

Common household chemicals such as those found in nonstick cookware, food packaging, and fabrics-even microwave popcorn bags-can reduce the immune response to routine childhood immunizations. According to newly released study results, the more children are exposed to perfluorinated compounds (PFCs), the less likely they are to have a good immune response to vaccinations. The study is the first to link PFCs to immune problems in children.

PFCs don’t break down easily and persist in the environment for years. They have become common everywhere in the world and exist in humans and animals. Animal studies have shown that PFCs can weaken the immune system.

Researchers wanted to know whether this was happening in humans, so approximately 600 children in the remote Faroe Islands were studied because they were found to have blood levels of PFCs similar to those of US children.

They found that high levels of PFCs in 5- and 7-year-olds resulted in a much weaker antibody response to tetanus and diphtheria vaccines. Scientists have been concerned about a link between PFCs and developmental problems in children. The Environmental Protection Agency has taken steps to phase out the use of some PFCs.

Even though US exposure to PFCs may be falling, researchers say that the problem is that levels are not going down in other parts of the world and there are places where they are going up. One of those places is China, which is a problem for countries such as the United States that buy products from China.

Although the findings don't prove that the chemicals are harming the immune system, researchers say, it is "very likely" to be the case.

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