Pentachlorophenol: Health and Environmental Effects Profile

Pentachlorophenol is used as an industrial wood preservative for utility poles, crossarms, fence posts, and other purposes (79%);for NaPCP (12%); and miscellaneous, including mill uses, consumer wood preserving formulations and herbicide intermediate (9%) (CMR, 1980). As a wood preservative, pentachlorophenol acts as both a fungicide and insecticide (Freiter, 1978). The miscellaneous mill uses primarily involve the application of pentachlorophenol as a slime reducer in paper and pulp milling and may constitute ∼6% of the total annual consumption of pentachlorophenol (Crosby et al., 1981). Sodium pentachlorophenate (NaPCP) is also used as an antifungal and antibacterial agent (Freiter, 1978). Pentachlorophenol also is used as a general herbicide (Martin and Worthing, 1977). Photolysis and microbial degradation are the important chemical removal mechanisms for pentachlorophenol in water. In surface waters, pentachlorophenol photolyzes rapidly (ECETOC, 1984; Wong and Crosby. 1981; Zepp et al., 1984); however, the photolytic rate decreases as the depth in water increases (Pignatello et al., 1983). Pentachlorophenol is readily biodegradable in the presence of accli-mated microorganisms; however, biodegradation in natural waters requires the presence of microbes that can become acclimated. A natural river water that had been receiving domestic and industrial effluents significantly biodegraded pentachlorophenol after a 15-day lag period, while an unpolluted natural river water was unable to biodegrade the compound (Banerjee et al., 1984). Even though pentachlorophenol is in ionized form in natural waters, sorption to organic particulate matter and sediments can occur (Schellenberg et al., 1984), with desorption contributing as a continuing source of pollution in a contaminated environment (Pierce and Victor, 1978). Experimentally determined BCFs have shown that pentachlorophenol can significantly accumulate in aquatic organisms (Gluth et al., 1985; Butte et al., 1985; Statham et al., 1976; Veith et al., 1979a,b; Ernst and Weber, 1978), which is consistent with its widespread detection in fish and other organisms. Direct photolysis may be an important environmental sink for pen tachlorophenol present in the atmosphere. The detection of pen tachlorophenol in snow and rain water (Paasivirta et al., 1985; Bevenue et al., 1972) suggests that removal from air by dissolution is possible. Soil degradation studies indicate that pentachlorophenol is biodegrad able; microb