An outbreak of lead poisonings in children, tied to contaminated cinnamon applesauce pouches, illustrates the gaps in how heavy metals in foods are regulated.

Despite strong efforts to limit lead exposure from sources like paint and gasoline, the U.S. government doesn’t broadly limit lead levels in food, a blind spot that’s become all the more glaring, experts say, as cases of lead poisonings in young children linked to contaminated cinnamon applesauce continue to mount.

As of Tuesday, lead poisoning had been reported in at least 65 children, all younger than 6, who ate pouches of now-recalled cinnamon apple puree and cinnamon applesauce, up from 57 cases two weeks ago, according to the Food and Drug Administration.

Children under the age of 6 are most vulnerable to lead poisoning, the Centers for Disease Control and Prevention says. The heavy metal can lead to developmental problems, damage to the brain and nervous system, and problems with learning, behavior, hearing and speech. Lead exposure can lead to lower IQ and underperformance in school, according to the CDC.