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Reducing breast milk concerns

Reducing breast milk concerns

For years doctors have extolled the benefits of breastfeeding infants while remaining concerned about the potential for mothers to unwittingly pass on environmental contaminants in their milk. Now, Purnendu “Sandy” Dasgupta, the Jenkins Garrett Professor of Chemistry and Biochemistry, has discovered that the risk might not be as great as feared.

How can breast milk be a potential danger?

We and other researchers have found in the past that there is a higher concentration of perchlorate, an environmental contaminant, in breast milk versus formula. The fear is that mothers would be exposed to it and pass it on to their children through their breast milk. While reports of high levels of perchlorate have not been widespread, it has caused some concern.

What harm could perchlorate potentially do?

Evidence suggests that the contaminant—which occurs naturally in the environment and in rocket fuel, fireworks, some fertilizers, and road flares—can block the uptake of iodine to the thyroid and disrupt the production of hormones necessary for normal neurological development. These effects would be particularly harmful to infants and young children.

But your study may help ease concerns.

Yes, our results suggest that nature has already devised a way to at least partly take care of the problem. We studied 18 pairs of infants and mothers and found evidence that breast-fed babies can in fact metabolize perchlorate, thus decreasing their potential for exposure if their mothers pass it on. The research indicates that it may be due to bifidobacteria, bacteria that are plentiful in the digestive systems of breast-fed babies.

So formula-fed babies wouldn’t be able to metabolize it as well?

No, but formula-fed babies get much less perchlorate anyway, so the risk of exposure is not as great for them as for breast-fed babies.