Heavy metals such as lead, arsenic, cadmium and mercury can be toxic to everyone, but exposure is especially dangerous for babies and toddlers. The neurotoxins can permanently damage developing brains, potentially causing long-term intellectual and behavioral problems.

Multiple reports in recent years have detailed concerning levels of these contaminants in foods manufactured for babies and toddlers. A 2019 report from the advocacy group Healthy Babies Bright Futures said that 95% of baby foods from major manufacturers contained lead and a quarter of the foods contained all four heavy metals. And in 2021, an investigation by the House Subcommittee on Economic and Consumer Policy found levels of heavy metals in baby food that were far above the limits set for bottled water.

Still, the FDA has set limits for heavy metals in only two baby foods: infant rice cereal and juice. And the standard set for rice cereal in 2020 – limiting inorganic arsenic to 100 parts per billion – was 10 times higher than the standard set for bottled water. The federal agency released draft guidance that would limit the amount of lead allowable in many popular baby foods early last year but hasn’t formally set any additional limits.

The Baby Food Safety Act of 2024, introduced on Thursday, would direct the FDA to develop maximum allowable limits for toxic heavy metals found in baby food more broadly. It would set standards for testing of the final food products and allow the FDA to monitor these standards through access to the records of food suppliers and manufacturers.

It would also bolster the FDA’s authority to enforce the limits it sets, allowing the agency to mandate that companies recall food products that don’t meet standards, as opposed to the voluntary recalls that have been the standard.

“Parents want what’s best for their children, and they deserve peace of mind knowing the food they purchase for their babies and toddlers is safe,” Sen. Amy Klobuchar, D-Minnesota, said in a statement about the bill she is leading. “This legislation will boost food safety standards and require more complete testing by manufacturers to prevent heavy metals from poisoning our kids.”

At a Senate subcommittee hearing Wednesday, FDA Commissioner Dr. Robert Califf asked Congress for more authority to oversee food manufacturers using a model that’s similar to how it oversees drug manufacturers – a request that aligns closely with the newly proposed legislation.

“In most of our regulatory paradigms, the first line of defense is the industry that we regulate,” he said. “Like in the production of medications, we don’t test every lot of medications, but the company that manufactures the drug is required to do it, and they have the records available for us to look at. And we’d like to see the same thing happen not only with infant formula but also with regard to all critical foods, particularly for children.”

FDA also seeks new authority to require that manufacturers report contamination that they find in critical foods such as infant formula or medical foods and conduct more frequent monitoring of facilities.

In 2021, the same group of lawmakers who sponsored the new bill – Klobuchar and fellow Democrats Sen. Tammy Duckworth of Illinois, Rep. Raja Krishnamoorthi of Illinois and Rep. Tony Cárdenas of California – introduced similar legislation to reduce toxic heavy metals in baby food, but it didn’t have enough support to move farther.

And in December, as hundreds of children across the country were sickened by applesauce pouches that contained elevated levels of lead and chromium, they called on the FDA to use the authority of the agency’s new Human Foods Program to address the issue.

“All food manufacturers have a responsibility by law to meaningfully minimize or prevent chemical hazards, including through preventive controls to reduce or eliminate the presence of lead in their products,” the lawmakers wrote in a letter to Califf. “In light of recent harm caused by certain cinnamon applesauce and fruit puree products, it is clear that the agency must prioritize the work on heavy metal action levels.”

The primary way that toxic metals get into the foods we eat is through the soil that the foods are grown in, experts say.

“When you grow a plant, whether it’s a sweet potato or rice, the plant will take up the metals through its roots into the plant. That’s the bad news,” said Scott Faber, senior vice president for government affairs for the Environmental Working Group, a nonprofit environmental and consumer advocacy organization. “The good news is that it is easy to avoid toxic metals by choosing where you plant.”

And setting limits works, he said. Arsenic levels in infant cereal were cut in half after the FDA issued recommended limits, according to an analysis of data from the agency’s Total Diet Study.

In 2021, the FDA launched its Closer to Zero Initiative, a long-term strategy to reduce childhood exposure to lead, arsenic, cadmium and mercury in foods. The initiative aims to keep dietary exposure to environmental contaminants to as low as possible, while maintaining access to nutritious foods.

But the need for more substantial regulation is urgent, advocates say.

“Government actions to protect babies from the toxic heavy metals in their food are long overdue. Every day that passes, nearly 10,000 more babies in the U.S. begin eating solid food. The FDA must take swift action to protect the next generation of children,” Paige Whipple Glidden, communications director for Healthy Babies Bright Futures, said in an email. “Heavy metal contamination spans all the food aisles of the grocery store, and FDA’s safety standards should as well.”

CNN’s Sandee LaMotte contributed to this report.