Decreasing trends in methyldibromo glutaronitrile contact allergy – following regulatory intervention

Abstract

The preservative methyldibromo glutaronitrile (MDBGN) has been banned, first from stay-on, and later from rinse-off cosmetics, in the EU countries because of increasing rates of contact allergy. To evaluate the frequency of contact allergy to MDBGN among patients patch tested by the Danish Contact Dermatitis Group just before and following regulatory decisions. The data set comprised 19 279 consecutive eczema patients patch tested from 2003-2007 with MDBGN 0.3% in petrolatum (pet.) or, in a minority of patients, with Euxyl K 400 1.5% in pet. A significantly decreasing trend in the frequency of positive patch tests to MDBGN was found from 4.6% in 2003 to 2.6% in 2007 (P < 0.001). The decreasing trend was seen for both men and women. A significantly decreasing proportion of cases with a current relevance of contact allergy to MDBGN was also seen from 51.3% in 2003 to 29% in 2007 (P < 0.001). Regulatory interventions have already had a major effect on allergic disease due to MDBGN in Denmark. The same trends are likely to be seen in other EU countries.