Prevalence and clinical outcome of contact allergy to methylisothiazolinone/methylchloroisothiazolinone in Southern-East Norway. A retrospective case-study

The use of preservatives as methylisothiazolinone (MI)/methylchloroisothiazolinone (MCl) in cosmetic and industrial products has led to an epidemic of contact allergy to MI worldwide.1-4 However, to our knowledge, current data from Norway is missing. Hence, the latest available data from 2006 to 2008, reports a nationwide prevalence of MI/MCI contact allergy of 2%,5 in line with other European countries before 2010.6, 7