By CBS3 Staff

PHILADELPHIA (CBS) — A new study is raising chemical concerns about some popular Cheerios products. The Environmental Working Group says it found traces of the main chemical used in the weed Killer Roundup in five of the six Cheerios products it tested.

Some experts think that chemical causes cancer. Honey Nut Cheerios Medley Crunch and regular Cheerios had the highest levels.

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General Mills says food safety is a top priority and it’s working to minimize the use of pesticides on the ingredients it uses.

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Nature Valley products were also continued to test positive for trace amounts of the herbicide, the study found.