The Food and Drug Administration on Tuesday proposed significant limits on levels of lead in processed baby food that could reduce exposure to the contaminant by as much as 27%.

The new draft guidance applies to packaged foods — items sold in jars, pouches, tubs and boxes — intended for babies and children under 2 years old. It would limit the concentration of lead in fruit, vegetable and yogurt products to 10 parts per billion, and to 20 parts per billion for dry cereals and single-ingredient root vegetable products like mashed potatoes.

Because crops absorb nutrients from soil and the environment as they grow, they also take up contaminants like lead, the FDA said in its announcement.

"Although it is not possible to remove these elements entirely from the food supply, we expect that the recommended action levels will cause manufacturers to implement agricultural and processing measures to lower lead levels," the announcement said.

The FDA estimates the new limits could cut lead exposure by 24-27% from processed baby foods.

High levels of lead exposure can cause brain damage and other problems, particularly in young children.

"Neurological effects of lead exposure during early childhood include learning disabilities, behavior difficulties, and lowered IQ," the FDA's draft guidance says, adding, "Because lead can accumulate in the body, even low-level chronic exposure can be hazardous over time."

The proposed limits would not be binding, however. Rather, the FDA said, it "would consider these action levels, in addition to other factors, when considering whether to bring enforcement action" against a food manufacturer that exceeds the limits.

Before the proposed guidelines can be finalized, there will be a 60-day period of public comment.