TOXIC EFFECTS OF DICHLOROMETHANE ON THE GROWTH OF METHANOTROPHIC BACTERIA

The effect of a range of dichloromethane (DCM) concentrations on the g rowth of five obligate methanotrophic bacteria of the genera Methylomo nas, ''Methylosinus'', and Methylocystis was assessed. DCM concentrati ons of 78 mM were bactericidal for all strains. Concentrations of 7.8 mM-156 muM were bacteriostatic for Methylocystis parvus ACM 3309 and M ethylomonas aurantiaca HB2, and partially inhibitory for Methylomonas methanica strains ACM 3307 and HB1. ''Methylosinus trichosporium'' ACM 3311 grew in the presence of up to 780 gm DCM, but a concentration of 7.8 mM was bacteriostatic.