Application of the margin of exposure (MoE) approach to substances in food that are genotoxic and carcinogenic: Example: (CAS No. 96-23-1) 1,3-Dichloro-2-propanol (DCP)

1,3-Dichloro-2-propanol (DCP) is formed in foods under a variety of conditions. It was positive in a variety of in vitro genotoxicity tests, but was negative in two in vivo studies. DCP produced neoplasms at several sites in rats. Kidney tumours in male rats were selected as the critical tumour type. Dose–response modelling of the data for DCP gave a BMDL10 for combined kidney carcinomas and adenomas in male rats of 9.62 mg/kg-body weight (bw)/day. The exposure of humans was estimated at an average of 0.00009 mg/kg-bw/day and a high exposure of 0.000136 mg/kg-bw/day. The MOEs for these exposures were 100,000 and 70,000, respectively.