Kemin selects raw material suppliers after review and evaluation, and receives certificates of analysis on each lot of raw material purchased from the suppliers. Although the company performs additional testing at its own laboratory to verify suppliers' claims on the certificates of analysis, Kemin is investigating one of its tocopherol suppliers.

On April 3, certified lab results in Europe showed 40.035 nanograms/kilogram of dioxin in a single batch of Naturox IP Plus Dry, an antioxidant used in petfood. Kemin is replacing any unused antioxidants containing tocopherols from this supplier as a precaution.

Kemin has been in contact with all affected European customers to notify them that when the antioxidant is applied at recommended application rates, the amount of dioxin in finished petfood is 0.04 - 0.09 nanograms/kilogram—well below the maximum allowable limit for dioxin in Europe. The EU allowable limit for dioxin in finished petfood is 1.75 nanograms/kilogram. As a comparison, the US limit for dioxin is 200,000 nanograms/kilogram.