ABSTRACT
In the early experiments, it was the general conclusion that there were no effects of halogenated compounds on microorganisms. There seemed to be no damage to ammonification, accumulation of nitrate, or other normal soil parameters. Stenersen performed experiments to investigate whether absorption, metabolism, or excretion of DDT was the cause of resistance in the stable fly Stomoxys calcitrans. Hill and McCarty made use of an active anaerobic condition under an idealized situation to examine whether a group of chlorinated hydrocarbon pesticides were capable of being degraded. For a number of years many microbiologists had been certain that any organic compound could be degraded if the compound were exposed to microorganisms in the environment long enough. In reality, many forms of both fungi, bacteria and protozoa are able to resist breakdown in the soil; for example, sclerotia, chlamydospores, and Bacillus endospores persist for many years with very little loss in viability.
