The Daunting Task of Cutting Heavy Metals from Baby Food
In the meantime, botanists, soil chemists, and plant geneticists — who have long worked to reduce heavy metals in the food supply — continue to look for potential solutions, from new land management practices to nano-sized fertilizers to genetic engineering. Not all of these technologies are available yet; however, even when they are, eliminating heavy metals entirely won’t be easy.
Still, some experts are optimistic about the possibilities. While “there is no single magic bullet that can address this problem,” said Om Parkash Dhankher, a professor of crop biotechnology at the University of Massachusetts Amherst, “there are lots of technologies and practices that farmers can use.”
Some of these approaches have yet to be applied in large-scale interventions beyond the lab. “Scientists don’t even think about extension,” said Ganga Hettiarachchi, a soil and environmental chemistry scientist at Kansas State University, referring to a century-old partnership with the U.S. Department of Agriculture and land-grant universities to translate science for practical application in farms and food production. When it comes to the newest research on soil and land management, Hettiarachchi worries that farmers might not be aware of how to apply the latest research. But she is optimistic: “I do see that it’s changing.”
One challenge in tinkering with soil chemistry and plant genetics is blocking arsenic can affect the way a plant takes up other nutrients. “There is a balance between this, a tradeoff between the required nutrients and these toxic elements,” Parkash said. “It’s a very complex system.”
In recent guidance for arsenic in infant rice cereal, and for lead in baby food more broadly, the FDA notes that strict limits may not be possible for manufacturers. Pinson told Undark that although it is possible to produce rice with relatively low levels of arsenic, supply chain realities make it difficult to achieve low levels in rice-based baby foods, in part because sellers merge grains from multiple truckloads from different farms into single bins, making low-arsenic rice difficult to trace.
The manufacturing process can also increase concentrations in baby food products that make it on the shelf. The February 2021 Economic and Consumer Policy Subcommittee report found that, at least in tests from of one company’s products, inorganic arsenic levels were 28 to 93 percent higher in the finished products compared to ingredients. The report points to high levels of arsenic in additives — like vitamin mixes and spices — as the cause of the spike pre- and post-manufacturing.
If food companies can’t meet limits on heavy metals in their products, Elisabeth Davis, a spokesperson for the FDA, told Undark that there could be unintended economic consequences for consumers. This includes, she continued, “limiting access to foods that have significant nutritional benefits by making them unavailable or unaffordable for many families, or unintentionally increasing the presence of one environmental contaminant when foods are reformulated to reduce the presence of another.”
The FDA’s risk assessment estimated the average lifetime risk of cancer at different levels of infant rice consumption at various limits of inorganic arsenic. For white rice infant cereal, a limit of 100 parts per billion would reduce the risk of cancer by almost 19 percent, whereas limits of 75 and 50 ppb were calculated to reduce risk by 41 and 79 percent, respectively.
The hazard models the report’s authors used are a standard approach, but experts told Undark that the science of calculating health risks around heavy metal contamination is complex. While it is quite straightforward to calculate exposure from water, when it comes to food, White, from the Connecticut Agricultural Experiment Station said: “There isn’t a formula right now that could be used to actually calculate something like that.”
“Baby food manufacturers hold a special position of public trust. Consumers believe that they would not sell unsafe products. Consumers also believe that the federal government would not knowingly permit the sale of unsafe baby food,” the report read. Baby food manufacturers and federal regulators had “broken the faith.”
As for the FDA efforts on reducing heavy metal exposure so far, “it’s good, and I fully support getting closer to zero,” Hettiarachchi said. “But at the same time, I think we have to do much better.”