California’s attorney general, Bill Lockyer, has sued 33 companies that make or sell certain types of confectionery imported from Latin America after tests revealed the sweets contained levels of lead that may be harmful to children.

Lockyer asked a Superior Court judge to block sales of the sweets until health warnings are put on the labels, reported the Associated Press. Most of the affected sweets were imported from Mexico although some was from Brazil.

“Lead ranks as a major health hazard for children, who can suffer serious learning disabilities from even low levels of exposure. When a product as popular among children as candy contains lead, consumers and parents deserve to know,” Lockyer was quoted by the Associated Press as saying.  

Arturo J. Gonzalez, from the National Confectioner Association, said the association’s members’ Mexican sweets were safe to eat and complied with all US FDA food safety laws.

Gonzalez said California’s Proposition 65, which requires warning labels on substances that can cause cancer, does not apply to trace amounts of naturally occurring substances in foods. He argued that traces of minerals such as lead are found naturally in soil and water where plants grow, and so traces of them are also found in many foods.