The problem begins at the farm where plants draw toxins from the soil. There’s no washing them away.
The Food and Drug Administration’s new plan to keep high levels of lead out of baby foods like mashed sweet potatoes, apple sauce and dry cereal is part of a larger effort to eliminate heavy metals from the foods the youngest children eat.
The push follows years of studies by public health, consumer and government experts revealing concerning levels of arsenic in rice cereal and other items fed to infants, including big-name brands like Gerber and organic staples like Earth’s Best.
This problem is not confined to baby-food factories, though. Metals like cadmium and mercury often get into crops as the plants burrow into the ground, drawing in nutrients from contaminated soil — or from naturally occurring compounds. Here are some possible answers to how these heavy metals get into food, what growers can do to keep it out — and how parents of the tiniest diners can steer clear of tainted food.
How do heavy metals get into foods in the first place?
Rain washes pollutants from factories, landfills, animal feed lots or from roadway auto emissions into lakes, rivers and streams. These pollutants can travel through groundwater or irrigation streams and contaminate crops or soil, according to Laurie Beyranevand, director of the Center for Agriculture and Food Systems at Vermont Law and Graduate School.
Some of the metals occur naturally in the soil. Others can get added by certain fertilizers and insecticides, said Arthur Villordon, a professor at Louisiana State University who specializes in sweet potato farming.
As plants grow, some, like leafy greens, are particularly efficient at drawing in heavy metals and storing them in their leaves, roots or fruit.
Why do these metals get into baby foods?
Beyond contamination because of absorption from the soil, heavy metals can also find their way into baby food through additives like fortified vitamin mixes, said Evelyn Rusli, co-chief executive of Yumi, a baby food company that does extensive testing of its ingredients and finished products.
Why is that a particular concern for babies?
Heavy metals are not healthy for adults, but they are particularly bad for babies. Infants and toddlers grow rapidly, developing key body systems and laying the foundation for lifelong cardiovascular, immune and brain health. Because they are far smaller than adults, a small dose of any toxin can be harmful. They may also be less efficient at metabolizing toxins than adults. Small amounts of lead, for instance, have been found to affect behavior, I.Q. and academic achievement, according to the American Academy of Pediatrics.
What products should I avoid if I’m feeding a baby?
Rice, used in baby cereal and snack puffs, is consistently identified in studies as the food with the highest levels of arsenic, which is associated with cancer. The problem is believed to stem from rice farming in fields that are flooded year after year with water that can contaminate the soil. (Scientists are working on ways to minimize the problem.)
Dry rice cereal is often one of the first foods parents are urged to mix with breast milk or formula when a baby begins the transition from a liquid diet to solid food. Dry oatmeal cereal is a better alternative, according to a report by Healthy Babies Bright Futures, an advocacy group.
Other foods found to have the lowest levels of heavy metals include peas, green beans, butternut squash and bananas. Beans, eggs and soft meat in traditional baby food or prepared at home are low-metal forms of protein, the report says. Serving a wide variety of fruits and vegetables — instead of relying heavily on carrots and sweet potatoes — can help reduce overall exposure to heavy metals.
Why aren’t the foods tested before they get on the market?
While some food companies monitor toxin levels, they are not required to report the results to the public or to list them on product labels. The F.D.A. has broad mandates that food makers ensure their products are safe, but there are few actual limits for specific toxins. The F.D.A. has set an “action limit” for inorganic arsenic in rice cereal marketed for babies and has proposed one for lead in juice.
These limits — like those proposed for lead in baby food — do not set a strict bar. Rather, they create guidelines for food makers to voluntarily follow. If the F.D.A. finds that a company exceeds the levels, it can pursue enforcement action, which can lead to a product recall, seizure or a recommendation for criminal prosecution.
What can be done to remove metals from foods?
Washing produce will not help. But there are agricultural techniques that can reduce the levels seeping into crops. Farmers can test soil and use contaminated fields for crops that do not tend to pick up the metals, like beans. They can also use fields with suboptimal soil to grow lavender or other crops that might not be eaten, Ms. Beyranevand, of Vermont Law, said. Farmers are also trying to reduce toxins by growing crops — such as sunflowers and poplar trees — that are efficient at drawing impurities out of the soil and then disposing of the plants.
Agriculture experts are studying hundreds of varieties of plants that people eat to determine which are the least likely to harbor heavy metals, according to the Healthy Babies Bright Futures report.
What can food companies do?
Ms. Rusli, of Yumi, said her company reviewed soil content data from the Environmental Protection Agency to buy produce for its baby food from regions with lower levels of contamination. It also conducts testing before entering into contracts with farmers and tests finished products to ensure that metals aren’t added during processing.