Cadmium Intake from Six Foods Analyzed by Age Group

Washington D.C. – A new dietary cadmium risk review combines exposures from six different foods that appear to exceed limits set by a federal public health agency for young groups.

The risk analysts found that 2-5 year olds were the most highly exposed group next to 6-24 month olds to the metal cadmium from six common foods in a comparison across diet surveys.

“American infants and young children of these age groups who regularly consumed rice, spinach, oats, barley, potatoes and wheat had mean cadmium exposures exceeding limits” set by the Agency for Toxic Substances and Disease Registry [A branch of the Centers for Disease Control & Prevention], according to the study.

However, none of the cadmium exposures in any of the age groups in the United States exceeded cadmium limits set by other regulatory agencies worldwide: the European Food Safety Authority (EFSA) and the Joint Expert Committee on Food Additives (JECFA) of the Food and Agriculture Organization and World Health Organization.

Background

Cadmium is a naturally occurring metal that finds its way into crops through atmospheric deposition from smelting operations, mining, combustion, sludge, landfills and water sources. At sufficient levels of exposure, it can damage the kidneys and lead to some cancers. Mitigation options for reducing metals in the food supply are also a focus of the research.

The risk analysts conclude, “At the mean food intake and mean cadmium levels, the cumulative exposure from just six food items, commonly used in commercial baby food manufacturing, exceeded ATSDR’s chronic oral MRL [Minimal Risk Level] values for the 6-24 and 24-60 month age groups.”

The new review is available online, “Dietary Exposure to Cadmium from Six Common Foods in the United States,” and will appear in the August 2023 print issue of the journal Food & Chemical Toxicology. The research was supported by the Institute for the Advancement of Food and Nutrition Sciences and the U.S. Department of Agriculture.

The authors, Ashish Pokharel and Felicia Wu of Michigan State University, direct attention to young groups’ exposures to metals like cadmium because children are still developing when these exposures occur.

Low Absorption

Cadmium can result in adverse health effects: at elevated exposure levels it may accumulate in the kidneys and contribute to renal dysfunction. However, because a small percent of cadmium is absorbed in the gut, the authors express caution about making firm conclusions about health effects.

“..we advise caution in extrapolating to particular health effects. Most ingested Cd passes through the gastrointestinal tract without being absorbed and it is estimated that only 1-10% of the total Cd is absorbed in the intestines…” they write.

The combined exposure estimates in the risk review were in part built from adding the cadmium together found in 27 samples each of rice and spinach — common ingredients in baby, toddler and many other foods. The samples were drawn from across different regions of the U.S. Other exposure databases were also used in generating the estimates.

Agile Science

As U.S. lawmakers scrutinize the metal contents of baby foods through hearings and reports, the authors say policymakers should prioritize mixtures.

Although the individual foods tested by themselves didn’t trigger any federal limits for cadmium in the analysis, the authors say mixed ingredient foods warrant policymakers’ attention.

In pureed and mixed ingredient foods “…exposure to cadmium may come from multiple different ingredients with highly diverse cadmium levels,” the authors conclude.

The findings may complicate communications around healthy foods as the six foods surveyed contain important nutrients and fiber — benefits long understood to be healthy.

In response, Wu of Michigan State University, says “It is still important to convey the nutritional benefits of foods that may contain cadmium. An important next step is to identify cost-effective and feasible methods of reducing the amount of cadmium these crops take up from the soil.”

The study is available here.

The Institute for the Advancement of Food and Nutrition Sciences (IAFNS) is a 501(c)(3) science-focused nonprofit uniquely positioned to mobilize government, industry and academia to drive, fund and lead actionable research. This work was supported by IAFNS Food Chemical Safety Committee. For more information, visit iafns.org.