The search for fungal strains capable of pentachlorophenol degradation led to the isolation and identification of 98 different micromycetes. When these strains were submitted to toxicity tests in aquatic microcosms at concentrations of 10 mgL-1 and 100 mgL-1 PCP, inhibition of growth was 57% and 36% respectively of the total isolated and identified strains. Among the strains inhibited at 10 mgL-1, 6 can serve as bioindicators of PCP pollution while the strains resistant can be regarded as potential PCP biodegraders. It was confirmed that fungal strains isolated from sites contaminated by chemically different products manifest different levels of sensitivity to PCP toxicity and probably different biodegradation potentials.