Baby Health - First Evidence Common Pollutant - Perchlorate May Reduce Iodine Levels in Breast milk
Posted Oct 14 2008 4:14am
By Colleen Hurley, RD, Certified Kids Nutrition Specialist
Although chemicals like BPA and phthalate have been getting lots of press, that does not mean they are the only inorganic materials in our food and water supply. There can, at times, be an array of different substances in what we eat and drink due to pollutants or factory run-offs that end up in the soil and water. Many of the substances, however, are inert or found in such small amounts they do not disrupt our own basic chemistry. In the first human study of its kind, one common pollutant has been found to alter the composition of breast milk.
Texas based researchers found that an increasingly common pollutant called perchlorate may interfere with the bioavailability of the iodine in breast milk, thus decreasing an infants intake. Perchlorate naturally occurs in soil but is also produced for use as rocket fuel and explosives. Previous studies have found that perchlorate did indeed inhibit iodine uptake, but little was known about how the pollutant affected the iodine levels in breast milk.
In order to discover perchlorates affect on breast milk composition, researchers collected milk samples from 13 nursing mothers and measured content of iodine and perchlorate, as well as another known iodine inhibitor called thiocyanate. The researchers found that if the sample were fed to infants, almost all would have inadequate iodine intake.
In addition, researchers found that 9 of the infants would ingest perchlorate at a level higher than what the National Academy of Sciences has deemed safe. Iodine deficiency in infants can result in mental retardation, stunted growth, and diminished intelligence. Although the number of women in the study was small, researchers note the number of samples analyzed is the most extensive on the topic to date.
What You Can Do
Since the advent of iodized salt, iodine deficiency in industrialized countries is rare yet does remain a problem in developing nations. Iodine deficiency is the number one cause of preventable mental disabilities in children worldwide. As salt is in many of the foods we eat, it is likely you are getting adequate amounts. Most prenatal vitamins contain adequate amounts of iodine to meet the increased needs during pregnancy and lactation. Speak with your physician or dietitian about making sure you are getting adequate nutrients while pregnant and nursing.