The Kellogg Company has recently recalled 28 million boxes of children's cereals. The recall was prompted after complaints were received from 20 consumers, five of whom were nauseated and vomited after eating or smelling Kellogg's cereals.

Kellogg has not made a public statement identifying the subtance in question. But the Environmental Working Group (EWG) called Kellogg's 1 - 800 number and learned that the substance was a petroleum-based compound called methylnaphthalene. It had leached into the cereal from the package liner.

"Methylnapthalene contamination in cereal raises safety questions. The chemical is structurally similar to naphthalene, which was the primary component in mothballs until those products were reformulated due to toxicity concerns. Naphthalene and methylnapthalene share the same toxicity to lung cells. Naphthalene is also toxic to red blood cells, causing anemia, fatigue, nausea, vomiting and diarrhea (ATSDR 2005). The methylated form of the mothball chemical has not been fully assessed for toxicity to blood cells, a critical data gap when it comes to evaluating the potential effects of food contamination. The National Library of Medicine’s Hazardous Substances Data Bank lists these symptoms as a concern for workers exposed to methylnapthalene (NLM 2010)."

http://www.ewg.org/health-risks-from-packaging