Allyl Chloride: The Mutagenic Activity of Its Photooxidation Products

Irradiations of C3H5CI/NO_x, C₃H₅C1/C₂H₆/NO_x, and C₂H₆/NO_x mixtures were conducted in a 22.7-m₃ Teflon smog chamber, operated in a static mode. The irradiated mixtures were tested for mutagenic activity by periodically exposing Salmonella typhimurium strain TA100 to the smog chamber effluent during the irradiation. The allyl chloride photooxidation products’ total mutagenic activity was found to be dramatically dependent on the presence of Cl atom reaction products. In the absence of C₂H₆, which is used as a Cl atom scavenger, the observed mutagenic activity of the irradiated C₃H₅C1/NO_x mixture at long extent of reaction was 13 revertants-plate_-1-h_-1.(ppb C₃H₅CI consumed)_-1. However, when sufficient C₂H₆ was present to remove all Cl atoms, the observed mutagenic activity for C₃H₅C1 photooxidation products was 1.4 revertants·plate_-1·h_-1· C₃H₅C1 consumed)_-1. Under conditions of excess C₂H₆, the mixture is approximately 30 times more mutagenic than that previously observed for the mutagenic activity of the photooxidation products of propylene, the nonchlorinated analogue of allyl chloride. The observed mutagenic activity in the presence of excess C₂H₆ is consistent with the total response caused by chloroacetaldehyde, a primary C₃H₅C1 photooxidation product.