Plants, terrestrial pentachlorophenol

Pentachlorophenol in terrestrial ecosystems clears rapidly (Haque et al. 1988). In one case, a terrestrial ecosystem was given a single surface application of radiolabeled PCP equivalent to 5 kg sodium pentachlorophenate/ha. PCP residues on foliage decreased rapidly, with 50% metabolized within 15 days. After 131 days (autumn), most of the remaining PCP was in the topsoil and plant litter. After 222 days (winter), 39% of the radiocarbon remained. There was little bioconcentration in the resident fauna, due to rapid metabolism and excretion (Haque et al. 1988). 

The toxicity of commercial or technical grades of PCP significantly exceeds that of analytical or purified PCP. Some of this added toxicity is attributed to impurities such as dioxins, dibenzofurans, chlorophenols, and hex-achlorobenzene. Pentachlorophenol is rapidly accumulated and rapidly excreted, and has Utile tendency to persist in Uving organisms. It acts by uncoupling oxidative phosphorylation. Terrestrial plants and soil invertebrates were adversely affected at 0.3 mg PCP/L (root growth), and at 1.0-5.0 g PCP/m soil (reduction in soil biota populations). 

In a terrestrial ecosystem, the distribution of pentachlorophenol in soil, plant, air and leachate were 65, 9, 25 and 0.3%, respectively (Gile and Gillet, 1979). 

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