Kellogg’s recalled four funky-smelling cereals late last month — and now we know what funky chemical was causing the foul odor. Methylnaphthalene is the petrochemical that caused nausea and vomiting — and a recall for Kellogg’s Apple Jacks, Corn Pops, Froot Loops and Honey Smacks.

Methylnaphthalene isn’t an ingredient in these cereals — or at least isn’t supposed to be. The petrochemical is used in the packaging for these cereals, but it apparently leached into the sugar-laden “food.”

How concerned should you be if you plugged your nose and ate the foul-smelling edible food-like substance anyway? We don’t know. According to the Environmental Working Group, “health agencies know very little about its safety” — though the few studies that have been done do show some cause for concern:

Methylnaphthalene, which has two forms, is a component of crude oil and coal tar and may also be formed “as a pyrolytic byproduct from the combustion of tobacco, wood, petroleum-based fuels and coal” (EPA 2003)…. The chemical is known to be a commonly detected air pollutant from cigarette smoke, diesel and gasoline engine exhaust, wood smoke, tar and asphalt (ATSDR 2005). Animal studies show that methylnaphthalene causes lung damage when exposure occurs via inhalation, ingestion and skin contact. Mice given feed containing 0.075 percent or 0.15 percent of 1- or 2-methynaphthalene for 81 weeks had lung damage known as “pulmonary alveolar proteinosis,” marked by abnormal lipids, proteins and fluid in the lung (ATSDR 2005, citing Murata 1993, 1997). Applying a mixture of 1- and 2-methylnaphthalene to the skin resulted in similar lung injury to mice (Murata 1992)….
In 2005, the Agency for Toxic Substances and Disease Registry concluded: “The available data on the methylnaphthalenes appear inadequate to determine their carcinogenicity potential in humans.” (ATSDR 2005).
Despite inadequate studies, millions of pounds of methylnaphthalene are being produced every year — and as the Kellogg’s recall shows, the chemical is making its way into our food supply. EWG’s report on methylnaphthalene shows the need for stronger food safety and chemical regulation laws.

In the meantime, my suggestion is to try and reduce your consumption of overpackaged foods — especially if they are sugar-heavy foods that come from a company that’s repeatedly run afoul of government agencies.

The opinions expressed by MNN Bloggers and those providing comments are theirs alone, and do not reflect the opinions of While we have reviewed their content to make sure it complies with our Terms and Conditions, MNN is not responsible for the accuracy of any of their information.