Ex vivo prediction of the sensitization potential of biocides

Biocides are widely used in the workplace, mainly in the industrial and healthcare sectors. Because of their potential hazard for human health, their use is regulated on the European market. In particular, the sensitization potential of these substances must be identified in order to implement avoidance of exposure or measures maximizing protection of exposed employees. The objective of this study was to predict the sensitization potential of 24 biocides used in the workplace. For this purpose, the expression of two co-stimulatory markers and four chemokines was analyzed by flow cytometry in murine bone marrow-derived dendritic cells (BMDCs) exposed to the substances. Twenty-two substances induced cell activation with a concentration effect and were identified as sensitizers. Based on the BMDC model, these substances were classified into four potency categories: six extreme sensitizers, twelve strong sensitizers, two moderate and two weak sensitizers. All these biocides, except the ones classified as extreme, induced an upregulation of chemokines secretion in BMDCs. To conclude, the majority of the biocides tested were identified as potential sensitizers. These data underline the need to handle such substances with care in a preventive occupational context.