You do everything right. You eat your organic produce, free-range meat and eggs, and hormone-free milk. You studiously avoid plastic containers that could leach Bisphenol A (BPA), a possibly toxic estrogen-mimicking compound. Does it matter? A new study indicates that it does—but only to a point. In fact, you could eat an organic, local diet without any plastic exposure and still end up with high levels of toxic chemicals in your body.
Dr. Sheela Sathyanarayana, a pediatrician focused on endocrine-disrupting chemicals and health impacts at the Seattle Children’s Research Institute, noticed that her patients often asked how they could reduce exposure to endocrine disruptors at home. So she and her colleagues set up a study to test the efficacy of a written recommendation versus a five-day catered diet to see which (if either) would reduce exposure to BPA and pthalates, a group of chemicals used in plastics that have been linked to cancer, birth defects, and more. The results, published this week in the Journal of Exposure Science and Environmental Epidemiology, were somewhat shocking.
Sathyanarayana’s study consisted of 10 families. One group of random participants was given written guidelines from the national Pediatric Environmental Health Specialty Unit on avoiding BPA and pthalates in daily life (i.e. avoid canned foods when possible). The other group was given catered food and drink from a local company that offers organic, fresh, and local items. Both groups were asked to drink filtered water and avoid plastic drink containers. "People tend to focus on the organic part of it, but it was also fresh foods when possible, and no plastic used in cooking, preparation, or storage of foods," she explains.
The researchers assumed that urinary BPA and pthalate levels would drop in the catered group compared to the group using written instructions—people are generally bad at following advice from their doctors after all. "Instead we saw big spikes and increases in the catered diet group and no changes at all in the written education group," she says.
Sathyanarayana’s team tested the food samples in the catered group to find the source of contamination. The culprits: milk, cream, ground coriander, and other spices. "I honestly don’t know why the spices were more contaminated or why the dairy had higher contamination, but I do know it’s consistent with other reports," she says. In general spices, high fat dairy, and animal fats tend to have higher phthalate concentrations—but not at the levels reported in Sathyanarayana’s study.
What happened? Remember: That milk came from local farms in glass containers. And the coriander and other spices, while not local (many aren’t produced in the U.S.), came from an organic company trusted by the caterer.
Nonetheless, Sathyanarayana stresses that this doesn’t mean chemical exposure is out of our hands. "We do have national studies that [look at] general population exposures, and they don’t see concentrations this high. Other food studies don’t document concentrations in food this high either," she says. "It was a fluke in the sense that we happened to have a catered diet with several spices and dairy with higher concentrations."
It’s not like going vegan would have solved the problem. The kids in the study had higher phthalate concentrations, possibly because the caterer gave the families snacks (bread, cheese, etc.) that they turned into grilled cheese. "But even without the dairy, we still wouldn’t have seen results we’d hope to see," says Sathyanarayana.
The authors conclude in their study: "It may be that our findings reflect an isolated rare contamination event because of unusual processing or a packaging abnormality. It also could be the case that the food supply is systematically contaminated with high phthalate concentrations, which are difficult to identify."
Sathyanarayana isn’t planning to dig deeper in the supply chain to figure out where the chemicals came from—that falls outside her research interests, though she hopes that advocacy groups will pursue the issue.
There are still ways to reduce BPA and phthalate exposure, despite what the study’s results indicate. Sathyanarayana recommends a fresh food diet with reduced animal fat and canned food intake. "Diet can really contribute to your chemical exposure," she says.