Attorney General Phil Weiser is looking out for the well-being of the youngest Coloradans, according to his office, as he joined a coalition of 23 states’ top prosecutors who want to remove any toxic heavy metals from food for infants and toddlers.

“We must work together to protect our children in Colorado and across the country,” Weiser said in a statement. “The FDA can and should act quickly to stop manufacturers that have allowed toxic heavy metals into the food we give our children when they are at their most vulnerable.”

A press release from Weiser’s office cited a February congressional report that cited high levels of such toxins as arsenic, lead, cadmium and mercury in baby food sold by at least four of the seven largest U.S. manufacturers: Nurture, Beech-Nut, Hain and Gerber, all four that responded to the request for internal testing information. Walmart, Campbell and Sprout Organic Foods “refused to cooperate” with the investigation, the congressional reported stated.

“The Subcommittee is greatly concerned that their lack of cooperation might be obscuring the presence of even higher levels of toxic heavy metals in their baby food products than their competitors’ products,” reported the investigation by the House Oversight and Reform Committee’s Subcommittee on Economic and Consumer Policy.

The U.S. Food and Drug Administration does set limits on toxic metals in other foods, it has not similarly regulated baby food, and has, except for inorganic arsenic in one type of baby food, rice cereal.

The American Academy of Pediatrics notes that low levels of such toxins in baby food is a relatively low amount of a child’s overall toxic metal exposure risk, but all sources should be minimized.

Heavy metals can harm a developing brain, which is linked to problems with learning, cognition and behavior. The metals are a natural part of the environment, but make their way into foods through manufacturing and packaging.

The safest solution to reduce exposure, the academy recommends, is for parents to make their own baby food from natural ingredients.

The letter signed by Weiser and other state AGs calls on federal regulators to limit heavy metals faster than what was recommended in an April FDA report called “Closer to Zero: Action Plan for Baby Foods,” which would not start until the middle of next year and wouldn’t limit inorganic arsenic until April 2024, then limit cadmium and mercury sometime after that.

The attorneys general want the FDA to impose all new limits no later than next April, the narrowest window for the such a regulatory request.

Weiser was joined on the request by attorneys general from California, Connecticut, Delaware, Hawaii, Illinois, Iowa, Maine, Maryland, Massachusetts, Michigan, Minnesota, New Jersey, New Mexico, New York, Nevada, North Carolina, Oregon, Pennsylvania, Vermont, Virginia, Washington and Wisconsin.