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A case is presented involving an acute fatality resulting from self-administered dichlorophen, a chlorophenol fungicide. The compound was quantified using gas chromatography/mass spectrometry after extraction with methyl-tert-butyl ether, derivatization by methylation and separation on a HP5-MS capillary column. The blood concentration was 9.77 mg/l and other drugs, including ethanol, were not detected.
OBJECTIVES: To determine blood and urine concentrations of a number of metals and organic substances in workers at a hazardous-waste incinerator (HWI) 1 year after regular operations in the facility, and to compare these concentrations with the baseline levels. METHODS: The employees were divided into three groups according to their workplaces. Plasma analyses of hexachlorobenzene (HCB), polychlorinated biphenyls (PCBs 28, 52, 101, 138, 153 and 180) and polychlorinated dibenzo- p-dioxins and dibenzofurans (PCDD/Fs), and urinary analyses of 2,4- and 2,5-dichlorophenol (DCP), 2,4,5- and 2,4,6-trichlorophenol (TCP), pentachlorophenol (PCP) and 1-hydroxypyrene (1-HP) were carried out. The blood concentrations of beryllium, manganese, mercury and lead, and the urine levels of cadmium, chromium, nickel and vanadium were also determined. RESULTS: The current plasma HCB, PCB and PCDD/F levels, and the urine levels of chlorophenols (CLPs) and 1-HP did not show significant differences between workplace groups or the baseline concentrations. Moreover, no significant differences between metal levels could be observed. DISCUSSION AND CONCLUSION: The lack of differences between the current levels of metals and organic substances and the respective baseline concentrations, together with the absence of differences depending on the workplace indicate that the potential exposure of HWI workers to the analyzed compounds was insignificant. According to these results, 1 year of potential exposure to the above metals and organic substances would not mean any specific health problem for the workers at the HWI.
OBJECTIVE: To assess baseline concentrations of a number of metals and organic compounds in blood and urine of 28 workers employed at a new hazardous waste incinerator (HWI), before operation of the plant. METHODS: Plasma analyses of hexachlorobenzene (HCB), polychlorinated biphenyls (PCB 28, 52, 101, 138, 153 and 180), benzene, toluene, ethylbenzene, m-xylene, and polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) were carried out. The urinary levels of 2,4- and 2,5-dichlorophenol (DCPs), 2,4,5- and 2,4,6-trichlorophenol (TCPs) and pentachlorophenol (PCP), as well as those of 1-hydroxypyrene (1-HP) were also measured. Beryllium (Be), manganese (Mn), mercury (Hg) and lead (Pb) concentrations were determined in total blood, while the levels of arsenic (As), cadmium (Cd), chromium (Cr), nickel (Ni) and vanadium (V) were measured in urine. RESULTS: The levels of benzene, toluene, ethylbenzene and m-xylene were under their respective detection limits. The concentrations of HCB, PCBs and PCDD/Fs in plasma of the HWI workers, chlorophenols (CLPs) and 1-HP urinary concentrations, as well as those of metals in blood and urine are shown. PCDD/F concentrations in plasma of the new HWI workers ranged between 13.4 and 84.0 pg international toxic equivalents (I-TEQ)/g lipid, with a geometric mean value of 24.4 pg I-TEQ/g lipid. DISCUSSION: PCDD/F levels, as well as the concentrations of PCBs were of the same order of magnitude as those recently obtained for non-occupationally exposed populations of Catalonia (Spain). No significant gender differences were found for the levels of HCB, PCBs and PCDD/Fs. Although the present results showed a notable variability in the levels of CLPs, geometric mean values of these compounds were similar or even lower than those considered as potential reference values. Metal concentrations in blood and urine were also of the same order of magnitude than previously reported metal levels in the same area. CONCLUSION: The present results should be useful in future surveys in which internal exposure of the HWI workers will be determined.
UNLABELLED: The aim of the study was to investigate the concentration of organochlorine compounds of environmental-medical relevance in biological materials from refugees with regard to their countries of origin and to compare these concentrations with the internal exposure of the German general population. METHODS: During medical examination after entry to Germany specimens could be taken from the refugees to determine the following parameters of biological monitoring: 1,1-dichloro-2,2-bis(-chlorophenyl)-ethylene (DDE-P), polychlorinated biphenyls (PCB-P), pentachlorophenol (PCP-P) and the beta- and gamma-hexachlorocyclohexanes (beta-HCH-P, gamma-HCH-P) in plasma and the excretion of chlorophenols (4-MCP-U, 2,4-DCP-U, 2,5-DCP-U, 2,4,5-TCP-U, 2,4,6-TCP-U, 2,3,4,5-TeCP-U, 2,3,5,6-TeCP-U) in urine. One hundred and three men (13 from former Yugoslavia, 29 from the former USSR, 33 Africans and 28 Asians) ranging from 16 to 53 years of age (median 27 years) were investigated. Thirty four male Germans without occupational exposure to these substances and a similar age structure (age 25-36 years; median 26 years) served as a control group. RESULTS: A much higher level of internal exposure was found for the DDT metabolite, DDE, for those persons from Asia, the former USSR and Africa compared with the German controls (medians: 16.9 micrograms/l, 11.9 micrograms/l and 10.9 micrograms/l) and 1.1 micrograms/l). The levels of PCB in plasma were below the detection limit in the majority of refugees. In the control group, however, the PCB levels were higher (sigma PCB; median: 2.1 micrograms/l, maximum: 13.3 micrograms/l). The highest beta-HCH concentrations, up to a maximum of 15.5 micrograms/l, were detected in the persons from the former USSR and Asia. The five groups do not differ with regard to internal exposure to PCP and gamma-HCH. Renal excretion of 4-MCP, 2,4-DCP and TeCP did not differ between the five groups. The concentrations of 2,5-DCP in urine, however, were significantly lower in the Germans than the refugees from the four regions investigated. The median for the Germans was 3.0 micrograms/l and for the refugees between 10.8 and 14.7 micrograms/l. Also the levels of 2,4,5-TCP and 2,4,6-TCP in urine were lower in the German controls than in the men from the former USSR, Africa and Asia. CONCLUSIONS: Organochlorine compounds exist worldwide due to their extensive use. There are, however, regional differences for the various substance groups, which during biological monitoring are seen in the different background exposures of the general population. Particularly characteristic are markedly higher levels of DDE in plasma from the refugees compared with the German population.
A novel bioinorganic catalyst was obtained via reduction of Pd(II) to Pd0 on to the surface of cells of Desulfovibrio desulfuricans at the expense of H2. Palladised biomass, supplied with formate or H2 as an electron donor, catalysed the dehalogenation of 2-chlorophenol and polychlorinated biphenyls. In the example of 2,3,4,5-tetrachlorobiphenyl, the bioinorganic catalyst promoted a rate of chloride release of 9.33 +/- 0.17 nmol min(-1) mg (-1) and only approximately 5% of this value was obtained using chemically reduced or commercially available Pd0. In the case of 2,2',4,4',6,6'-hexachlorobiphenyl the rate was more than four orders of magnitude faster than the degradation reported using a sulfidogenic culture. Negligible chloride release occurred from any of the chloroaromatic compounds using biomass alone, or from palladised biomass challenged with hexane carrier solvent only. Analysis of the spent solution showed that in addition to catalysis of reductive dehalogenation the new material was able to remove very effectively the organic residua, with neither any PCB nor any breakdown products identifiable by GC/MS.
Herbicide-resistant sweet potato plants were produced through biolistics of embryogenic calli derived from shoot apical meristems. Plant materials were bombarded with the vectors containing the beta-glucuronidase gene (gusA) and the herbicide-resistant gene (bar). Selection was carried out using phosphinothricin (PPT). Transformants were screened by the histochemical GUS and Chlorophenol Red assays. PCR and Southern-blot analyses indicated the presence of introduced bar gene in the genomic DNA of the transgenic plants. When sprayed with Basta, the transgenic sweet potato plants was tolerant to the herbicide. Hence, we report successful transformation of the bar gene conferring herbicide resistance to sweet potato.
Prostaglandin (PG) synthesis from [1-14C]-arachidonic acid by bovine dental pulp microsomes was stimulated by 0.1-0.5 mM concentrations of p-chlorophenol (PCP) and inhibited by more than 3 mM. Dual effects (stimulation and inhibition) of phenol, PCP, o-, m-, p- and tri-cresol on PG synthesis by rabbit kidney medullary microsomes were observed. Of various compounds tested, eugenol, thymol and guaiacol were the most potent inhibitors; the inhibitory action was reversible. Phenolic compounds did not affect the activity of glucose-6-phosphatase, adenosine triphosphatase, or lactate dehydrogenase in rabbit kidney medulla within the range of concentrations that stimulated or inhibited PG synthesis. Thus the analgesic effect of phenolic medicaments in endodontic therapy may be due to inhibition of arachidonic-acid metabolism.
The oxidation-reduction midpoint potentials (Em) of the following compounds have been measured in the range of pH from 3 to 12 by polarography: methyl viologen; benzyl viologen; 2-hydroxy-1,4-naphthoquinone; 2-hydroxy-1,4-anthraquinone; N,N,N',N',-tetramethyl-p-phenylenediamine; 2,3,5,6-tetramethyl-p-phenylenediamine; phenazine; N-methylphenazonium methosulfate; N-methylphenazonium sulfonate methosulfate; N-ethylphenazonium ethosulfate; pyocyanine; neutral red; safranin; phenol red; chlorophenol red; cresol red; bromocresol purple; 2,5-dibromo-3-methyl-6-isopropylbenzoquinone and 5-n-undecyl-6-hydroxy-4,7-dioxobenzothiazole. Many of these previously assumed to have a simple behavior in this range have proven to be rather more complicated, and several anomalous observations have been reconciled.
Induction of cytosolic long-chain acyl-CoA hydrolases was investigated in rat liver after administration of various peroxisome proliferators and related compounds. Treatment of rats with di-(2-ethylhexyl)-phthalate, di-(2-ethylhexyl)-adipate or tiadenol induced hydrolases I and II, while acetylsalicylic acid induced only hydrolase II. Among the various phenoxyacetic acid derivatives and related compounds, 2,4,5-trichlorophenoxyacetic acid, 2-(4-chlorophenoxy)-2-methylacetic acid, 2-(2-chlorophenoxy)-2-methylpropionic acid and clofibric acid induced both hydrolases I and II, whereas 2, 4-dichlorophenoxyacetic acid induced only hydrolase II. All nine of the above-mentioned inducers also markedly increased the activity of peroxisomal beta-oxidation. Other compounds tested (2-chlorophenoxyacetic acid, 4-chlorophenoxyacetic acid, 4-chlorophenol, phenoxyacetic acid and phenoxy-2-methylacetic acid) were ineffective as inducers. These results suggest that inducers of acyl-CoA hydrolase II also enhance peroxisomal beta-oxidation activity, but do not necessarily induce acyl-CoA hydrolase I. The structure-inducing activity relationships of these compounds are discussed.
Serum sialic acid has been assayed enzymatically. The reaction includes neuraminidase hydrolysis of glycoprotein, cleavage of sialic acid to pyruvate by N-acetyl neuraminic acid (NANA)-aldolase, oxidation of pyruvate by pyruvate oxidase which produces hydrogen peroxide, and colorimetry of hydrogen peroxide using the peroxidase-p-chlorophenol-4-amino-antipyrine method. This method showed good correlation between a chemical method (r = 0.984), good recovery (98.8%) and good reproducibility (within-run-precision: 1.0% C.V.; day-to-day precision: 1.9% C.V). Intrinsic serum pyruvate produces an equimolar positive effect. The normal value range is 1.94 +/- 0.29 mmol/l (mean +/- S.D.,n = 24).
The state of the art of chromatographic methods used in the determination of herbicide residues in crops, food and environmental samples is reviewed. The main structural groups of herbicides, i.e., triazines, phenyl- and sulphonylureas, carbamates, uracils and phenoxyalkanoic and arylphenoxypropanoic acids, and important degradation products (dealkylated triazines, substituted anilines, chlorophenols) are considered. Advantages and drawbacks of gas (GC), liquid (LC) and thin-layer chromatography in this type of analysis are discussed. The characteristics of a modern chromatographic method for the determination of herbicide residues are summarized and trends in the development and combination of current GC and LC methods discussed.
DBA/2 mice, previously identified as "unresponsive" to aromatic hydrocarbons which induce microsomal enzymes in C57BL/6 mice, are more vulnerable to the convulsant effect of repeated doses of lindane than similarly treated C57BL/6 mice. Death in convulsions and higher blood and brain lindane concentrations indicate that less efficient disposition of lindane itself accounts for the greater vulnerability of the DBA/2 mice. The same two principal chlorophenolic metabolites of lindane were identified in the blood and tissues of both strains, but the time-courses of blood concentrations in response to repeated lindane dosing were different.
This study was undertaken to determine the ability of a series of 19 compounds representing different chemical classes of carcinogens to induce lung tumors in strain A/J mice after either ip or po administration. Aflatoxin B1, dibutylnitrosamine, 1,2-dimethylhydrazine, and methylnitrosourea induced a significant increase in the lung tumor response in both sexes after ip and po administration. Azaserine was active in both sexes only after ip administration. Benzene, 1,2-dibromoethane, and epichlorohydrin, following ip administration, produced significant increases in the tumor response in at least one sex. Aflatoxin B1, azaserine, benzene, 1,2-dibromoethane, dibutylnitrosamine, and epichlorohydrin were more active when given ip than after po administration. In contrast, dimethylhydrazine and methylnitrosourea were more active (in females only) when given po. 2-Acetylaminofluorene, azobenzene, chloroform, 1,4-dioxane, FANFT (N-[4-(5-nitro-2-furyl)-2-thiazolyl]formamide), lead subacetate, methylmethanesulfonate, beta-naphthylamine, beta-propiolactone, safrole, and 2,4,6-tri-chlorophenol did not induce lung tumors in strain A/J mice. These data confirm previous observations on the importance of the route of chemical administration on the lung tumor response in strain A mice, and on the inability of the lung tumor bioassay to detect certain liver and bladder carcinogens and unstable alkylating agents.
Eulachons return to the Fraser River each spring and migrate through the estuary to spawn in freshwater. During this migration they may be subjected to varying water quality conditions due to the discharge of domestic and industrial wastes and land drainage. Fish were captured at five estuarine stations in April 1986 and again at three stations in April/May 1988. The locations were from Steveston, at the river mouth, to Port Mann bridge, 31.0 km upstream, just above saltwater influence. Water samples, whole fish, gonads and pooled livers of both sexes were analyzed separately for selected organochlorine contaminants. Water and tissue samples contained chlorophenols from wood preservation operations and chloroguaiacols from pulp bleaching. Whole fish also contained DDE and DDD, while PCBs were present in some fish gonads in 1986, but not in 1988. With the exception of whole body concentrations of 2,3,4,6-tetrachlorophenol (TeCP), concentrations of pentachlorophenol (PCP), 3,4,5-trichloroguaiacol (3,4,5-TCG), tetrachloroguaiacol (TeCG), DDE and DDD in whole bodies, livers and gonads revealed an increasing trend with distance of the eulachon capture site upstream from the Fraser River mouth. Marked differences occurred in the concentration of contaminants in eulachon livers (for example, levels of 50.8 +/- 42.2 ng g-1 3,4,5-TCG at Steveston, and 446.4 +/- 222.5 ng g-1 at Port Mann). The relatively high lipid content of eulachons suggests them to be potential integrators of low-level contaminants in the Fraser River system. This, and their anadromous life history, recommend them as suitable annual monitors of selected organic compounds.
The acute toxicity of nine para-substituted phenols was determined using a pulse-exposure testing protocol and 8-day-old larval American flagfish (Jordanella floridae). Relative tolerance was assessed by determining the 2-h pulse exposure concentration causing 20 and 50% mortality (PE LC20 and PE LC50) over the subsequent 94 h. Four bioassays were run for each phenol and yielded the following mean PE LC20 values (mg 1(-1)) in descending order of toxicity: p-aminophenol, 0.06; hydroquinone, 0.13; phenol, 0.70; p-nitrophenol, 0.81; p-cyanophenol, 3.0; p-chlorophenol, 3.3; p-hydroxyacetophenone, 4.2; p-hydroxybenzyl alcohol, 6.4; and p-hydroxybenzoic acid, 170. These toxicities did not correlate significantly with either previously reported toxicity values for the photoluminescent bacteria Photobacterium phosphoreum, or with the log octanol-water partition coefficient. For some of the compounds, however, sensitivities were quite close to previously reported rainbow trout chronic no-observed-effect concentrations based on continuous exposure. Caution is urged with respect to applying "low-level" biota techniques or simple quantitative structure-activity correlations such as Kow when attempting to predict the toxicity of specific chemicals to fish.
The genotoxic potential of 6 disinfectants and their 9 metabolites was investigated by umu test. In the tested disinfectants, glutaraldehyde showed positive genotoxicity independent of metabolic activation system and acrinol was positive only in the presence of S9 mixture. Alkylaminoethylglycine, benzalkonium chloride, chlorhexidine digluconate and methylrosaniline chloride were negative in the presence or absence of S9 mixture. In some metabolites of benzalkonium chloride, chlorhexidine digluconate or glutaraldehyde, only pyrogallol showed positive genotoxicity in the absence of S9 mixture and the activity was not affected by the metabolic activation system. Aniline, p-chloroacetoanilide, p-chloroaniline, p-chlorophenol, decabutyldimethylamine, glutaric acid, phenol and pyrocatechol did not induce umu gene expression independently of the presence of S9 mixture. The results in the umu test of these compounds were compared with their findings in the liquid rec-assay and Ames test. The umu test is a more useful and simplified method for the detection of genotoxicity of the compounds with killing effects on tester bacteria.
The adsorption of phenol, p-chlorophenol and mercuric ions from aqueous solution onto activated carbon has been studied in fixed bed columns. The influence of varying parameters such as bed depth, solution flowrate and pollutant concentration has been studied. The Bed Depth Service Time has been used to analyse the experimental data and identify design correlations. Furthermore, an optimization procedure based on the Empty Bed Residence Time has been applied to the data.
A series of seven randomly selected potential halogenated water disinfection by-products were evaluated in vitro by the hydra assay to determine their developmental toxicity hazard potential. For six of the chemicals tested by this assay (dibromoacetonitrile; trichloroacetonitrile; 2-chlorophenol; 2,4,6-trichlorophenol; trichloroacetic acid; dichloroacetone) it was predicted that they would be generally equally toxic to both adult and embryonic mammals when studied by means of standard developmental toxicity "teratology" tests. However, the potential water disinfection by-product chloroacetic acid (CA) was determined to be over eight times more toxic to the "embryonic" developmental portion of the assay than it was to the adults. Because of this potential selectivity, CA is a high-priority item for developmental toxicity tests in pregnant mammals to confirm or refute its apparent unique developmental hazard potential and/or to establish a NOAEL by the route of most likely human exposure.