Case studies pentachlorophenol

The following case study illustrates the use of SCREEN. In this example we analyze a fire incident that occurred at a wood preserving facility. The incident involved a fire and explosion of six cylindrical vessels containing creosote and pentachlorophenol. Refer to Figure 15. 

Ocular Effects. A case-control study of office workers was conducted by Baj et al. (1994) to evaluate the risks of chronic exposures to inhaled formaldehyde, phenol and isomers of organic chlorohydrocarbons from Ksylamit which is a widely used liquid wood preservative reported to consist of a mixture of chlorinated benzenes, pentachlorophenol, alpha-chloronaphthalene, chloroparafifin, and kerosene . Twenty-two workers (18 women and 4 men) exposed for at least 6 months were the cases, and 29 non-exposed, non-smoking volunteers matched for age, sex, and place of residence were the controls. The authors indicate that all of the exposed workers developed chronic complaints, among them burning eyes, but that no remarkable increase in morbidity was found during the 6 months of exposure to Ksylamit , nor during the 3-year follow-up study (details of which were not provided). The authors attribute these symptoms to the irritant effect of the inhaled Ksylamit probably (based on the references provided) due to the formaldehyde vapor they assert emanates from the woodpreserving liquid. 

Case reports and case control studies in humans have suggested a possible association between cancer, including soft tissue sarcoma, acute leukemia, Hodgkin disease, and non-Hodgkin lymphoma, and occupational exposure to pentachlorophenol. However, in all cases concomitant exposure to other toxic substances may have contributed to the effects seen. "... 

Associations with chlorophenols were, however, analysed in two case-control studies nested within 24 of the 36 cohorts of the lARC study. These compared 11 cases of soft-tissue sarcoma and 32 cases of non-Hodgkin lymphoma with 55 and 158 controls, respectively (Kogevinas et al., 1995). Exposure to chlorophenols, phenoxy acid herbicides, dibenzodioxins and -furans and other agents was assessed by a team of industrial hygienists (Kauppinen et al., 1994). Odds ratios for non-Hodgkin lymphoma, not adjusted for exposure to other agents, were 1.3 (95% CI, 0.5-3.1) for any chlorophenol, 2.8 (0.5-17.0) for pentachlorophenol and 1.0 (0.3-3.1) for 2,4-dichlorophenol. No excess risk was found in relation to other chlorophenols, but the munber of exposed cases was small. The odds... 

In a study of 89 women (87% German) with repeated ( 2) miscarriages, Gerhard et al. (1998) found that blood concentrations of PCBs were higher than the reference level in 22% of the cases. The effect cannot be specifically attributed to PCBs because blood levels of other organochlorine compounds (pentachlorophenol, DDE, p- and y-hexachlorocyclohexanes, HCB) were higher than reference ranges in... 

The decomposition of benzene and naphthalene and its homologues by microorganisms has already been discussed earlier. The metabolizing mechanisms of naphthalenes in fish have been well studied [47, 49]. Decomposition products of chlorobenzene in daphnia, mosquitos, snails and fishes are the polar compounds chlorophenol and chloro-o-dihydroxybenzene amongst other compounds, those of nitrobenzene aniline, acetanilide, aminophenols and nitrophenols and those of hexachlorobenzene pentachlorophenol and unknown compounds [71]. Bromoben-zene is deactivated to the toxic bromophenol [217]. In the case of man and land mammals, studies have concentrated on the metabolism of benzene, toluene, xylenes and styrene, which are also significant in occupational medicine [12, 13, 136, 195, 196, 215-217], A comparison of the metabolism of benzene into phenol in various animal species with the aid of microsomal preparations of the lungs or liver yielded vast differences. However, it is possible for benzene, in part, to inhibit or prevent its own metabolism [218]. 

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