In pure form or in high concentrations, methylchloroisothiazolinone is a skin and membrane irritant and causes chemical burns. In the United States, accepted concentrations are 15 ppm in rinse-offs and 8 ppm in other cosmetics. In Canada, the accepted concentrations are 15 ppm and 7.5 ppm respectively.[3] The Canadian levels are also reflected in a paper published in the International Journal of Toxicology.[4]