Contact allergy to preservatives is an important public health problem. Ideally, new substances should be evaluated for the risk on skin sensitisation before market entry, for example by using a quantitative risk assessment (QRA) as developed for fragrances. As a proof-of-concept, this QRA was applied to the preservative methylisothiazolinone (MI), a common cause of contact allergy. MI is used in different consumer products, including personal care products (PCPs) and household cleaning products (HCPs). Aggregate exposure to MI in PCPs and HCPs was therefore assessed with the Probabilistic Aggregated Consumer Exposure Model (PACEM). Two exposure scenarios were evaluated: scenario 1 calculated aggregate exposure on actual MI product concentrations before the restricted use in PCPs and scenario 2 calculated aggregate exposure using the restrictions for MI in PCPs. The QRA for MI showed that in scenarios 1 and 2, the proportion of the population at risk for skin sensitisation is 0.7% and 0.5%, respectively. The restricted use of MI in PCPs does not seem very effective in lowering the risk on skin sensitization. To conclude, it is important to consider aggregate exposure from the most important consumer products into consideration in the risk assessment.

接触防腐剂过敏是重要的公共卫生问题。理想情况下，应在进入市场之前评估新物质的皮肤致敏风险，例如使用针对香水开发的定量风险评估（QRA）。作为概念验证，此QRA应用于防腐剂甲基异噻唑啉酮（MI），它是接触过敏的常见原因。MI用于不同的消费产品，包括个人护理产品（PCP）和家用清洁产品（HCP）。因此，使用概率综合消费者暴露模型（PACEM）评估了PCP和HCP中MI的总暴露量。评估了两种暴露情况：方案1计算了在PCP中限制使用之前的实际MI产品浓度的总暴露，方案2使用了PCP中MI的限制计算了总暴露。MI的QRA显示，在方案1和2中，有皮肤过敏风险的人口比例分别为0.7％和0.5％。PCPs中MI的限制使用似乎在降低皮肤过敏风险方面并不十分有效。总之，在风险评估中必须考虑最重要的消费产品的总暴露量，这一点很重要。