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PubMed1979

Carcinogenicity of oil shale tars, some of their components, and commercial products.

Bioassays for carcinogenicity of various primary processing products (crude oils or tars) and commercial products obtained from Estorian oil shale have been carried out since 1951. The products (undiluted or diluted) were painted twice weekly 50 times on the interscapular area of the skin of random-bred or CC57Br mice. The products processed at high temperatures have a higher carcinogenic activity. Blends of products containing over 10% of high temperature crude oil (chamber furnace oil) have about the same carcinogenic activity as the latter. There is no strict correlation between the concentration of benzo(a)pyrene (BP) in oil shale products and their carcinogenic activity. Determination of BP in such products can serve as an approximate estimate of carcinogenic properties. The results of animal experiments with chromatographic fractions of the high temperature shale oil demonstrated the presence of compounds which lengthen the latency period of the carcinogenic effect of BP in the aromatic fraction of this oil as well as other carcinogens and compounds enhancing the activity of carcinogenic compounds. Under industrial conditions, contact of workers with carcinogenic shale oils can be reduced by means of coking the carcinogenic oils, which results in production of solid coke and of distillate which is recycled. Medical vaseline potentiates the carcinogenic action of BP and similar compounds. Dilution of shale oils with oils containing aliphatic hydrocarbons cannot be considered as diminution of the carcinogenic potency of these products.

Animals↗
PubMed1994

Human peripheral blood lymphocytes as a cell model to evaluate the genotoxic effect of coal tar treatment.

Peripheral blood lymphocytes (PBL) from psoriatic patients therapeutically exposed to polycyclic aromatic hydrocarbons (PAH) during coal tar (CT) treatment were used to evaluate the in vivo formation of benzo[a]pyrene diol epoxide(BaPDE)-DNA adducts by an ELISA technique and by the 32P-postlabeling method. Moreover, we controlled if the pretreatment with CT influences the formation of BaP-DNA adducts and the BaP metabolism in the PBL obtained from psoriatic patients, treated in vitro with BaP. Our data did not show any significant influence of the CT treatment on the levels of PAH-DNA adducts. Moreover, the use of PBL from psoriatic patients, treated in vitro with BaP, did not allow to detect significant modifications of the metabolic activation of BaP and of the ability of its metabolites to bind to DNA, before and after CT treatment. Thus, PBL do not seem to represent an useful cell model to evaluate the possible genotoxic effect of the exposure through the skin of psoriatic patients to the PAH contained in CT.

7,8-Dihydro-7,8-dihydroxybenzo(a)pyrene 9,10-oxide↗
PubMed1998

Genotoxicity of bioremediated soils from the Reilly Tar site, St. Louis Park, Minnesota.

An in vitro approach was used to measure the genotoxicity of creosote-contaminated soil before and after four bioremediation processes. The soil was taken from the Reilly Tar site, a closed Superfund site in Saint Louis Park, Minnesota. The creosote soil was bioremediated in bioslurry, biopile, compost, and land treatment, which were optimized for effective treatment. Mutagenicity profiles of dichloromethane extracts of the five soils were determined in the Spiral technique of the Salmonella assay with seven tester strains. Quantitative mutagenic responses in the plate incorporation technique were then determined in the most sensitive strains, YG1041 and YG1042. Mutagenic potency (revertants per microgram extract) in YG1041 suggested that compost, land treatment, and untreated creosote soil extracts were moderately mutagenic with Arochlor-induced rat liver (S9) but were nonmutagenic without S9. However, the bioslurry extract was strongly mutagenic and the biopile extract was moderately mutagenic either with or without S9. A similar trend was obtained in strain YG1042. The strong mutagenic activity in the bioslurry extract was reduced by 50% in TA98NR, which suggested the presence of mutagenic nitrohydrocarbons. Variation in reproducibility was 15% or less for the bioassay and extraction procedures. Bioavailability of mutagens in the biopile soil was determined with six solvents; water-soluble mutagens accounted for 40% of the total mutagenic activity and they were stable at room temperature. The mutagenic activity in the bioslurry and biopsile samples was due to either the processes themselves or to the added sludge/manure amendments. The in vitro approach was effective in monitoring bioremediated soils for genotoxicity and will be useful in future laboratory and in situ studies.

Animals↗
PubMed1988

Prevalence of the misuse of ultra-low-tar cigarettes by blocking filter vents.

Evidence from tar-stain patterns in 135 cigarette filters discarded in ashtrays in public areas of shopping malls was used to estimate the prevalence of behaviorally blocked air dilution vents in ultra-low-yield cigarettes. Nineteen per cent (+/- 4, standard errors of the mean) of the filters had been blocked extremely, 39 per cent (+/- 5 SEM) had been blocked to some degree, and 42 per cent (+/- 5 SEM) had not been blocked at all. Smokers, health practitioners, and researchers need to be warned of the risks of vent blocking.

Behavior↗
PubMed1978

Biochemical decomposition of coal-tar dyes. I. Biochemical decomposition and identification of decomposed products.

Biochemical degradation test of food coal-tar dyes using sludge was studied in order to evaluate their safety. It was found that some dyes were little decomposed under aerobic condition but four azo dyes were readily decomposed under anaerobic condition. These were Food Yellow No. 4, No. 5, and Food Red No. 2, No. 102. Decomposed products of these four azo dyes by sludge under anaerobic condition were identified as sulfonilic, naphthionic acids and so on.

Aerobiosis↗
PubMed2000

Exposure to cigarette tar inhibits ribonucleotide reductase and blocks lymphocyte proliferation.

Cigarette smoking causes profound suppression of pulmonary T cell responses, which has been associated with increased susceptibility to respiratory tract infections and decreased tumor surveillance. Exposure of human T cells to cigarette tar or its major phenolic components, hydroquinone and catechol, causes an immediate cessation of DNA synthesis without cytotoxicity. However, little is known of the mechanisms by which this phenomenon occurs. In this report we demonstrate that hydroquinone and catechol inhibit lymphocyte proliferation by quenching the essential tyrosyl radical in the M2 subunit of ribonucleotide reductase.

Catechols↗
PubMed1987

Mortality of tar distillation workers.

Two hundred and fifty-five British tar distillery workers were followed from 1 January 1967 to 31 December 1983. Seventy-five men had died by the end of the follow-up, compared with 73.3 deaths expected on the basis of age-specific regional population death rates. Excess mortality occurred from lung cancer (12 deaths, 7.5 expected), bladder cancer (3 deaths, 0.7 expected) and diseases of the arteries and veins (5 deaths, 2.1 expected). Although the number of deaths from ischemic heart disease was not significantly increased overall (29 deaths, 25.3 expected), eight deaths from this cause occurred among men under 55 years of age compared with 3.9 expected. Four small matched case-referent studies, comparing men who died from these four causes with survivors, failed to reveal any associations between excess mortality and job type. In the light of other studies, it is concluded that the excess lung and bladder cancer mortality was work-related, while the deaths from ischemic heart disease and diseases of the arteries and veins merit further investigation.

Aged↗
PubMed2000

[A case of squamous cell carcinoma that developed on chronic tar dermatosis].

A 79-year-old Japanese man visited our clinic for evaluation of a large tumor on the left wrist and multiple keratotic tumors. He had handled creosote oil, which is a purified product of coal tar production, for 50 years. Physical examinations revealed poikiloderma with multiple hyperkeratotic tumors on the back of his hand and forearm bilaterally, and a cauliflower-like tumor, 80 x 60 x 15 mm in size, on the left wrist. Histopathologically, the large tumor showed a proliferation of atypical squamoid cells with many keratinization foci, indicating well-differentiated squamous cell carcinoma.

Aged↗
PubMed1990

The effect of clobetasol-17-propionate and crude coal tar on dithranol-induced inflammation. A clinical and biochemical study.

Clobetasol-17-propionate (CP) and crude coal tar (CT) have an anti-inflammatory potential. Both agents have been advocated to suppress irritation of the skin during dithranol treatment. The effect of CP and CT on dithranol-induced irritation was studied by the assessment of erythema and measurement of alkaline phosphatase (ALP) as a direct reflection of the metabolic activity of the endothelial cells. Dithranol was applied for 2 h in the relatively high concentration of 10%, which resulted in a marked inflammation of the skin in all volunteers. Neither CP nor CT influenced the erythema. In contrast, CP and CT had a synergistic effect on the dithranol-induced induction of ALP. In conclusion, the present study indicates that CP and CT are not indicated for the treatment of dithranol-induced irritation.

Adolescent↗
PubMed1998

[Detection of sister chromatic exchange in workers exposed to coal tar pitch and to coke oven volatiles].

In order to know the changes of genetic toxicological effects on workers occupationally exposed to polycyclic aromatic hydrocarbons (PAHs), sister chromatic exchange(SCE) was detected by the methods of peripheral lymphocyte culture in 23 workers exposed to coal tar pitch (CTP) and in 19 workers exposed to coke oven volatiles (COV) and 12 normal controls. The results suggested that the SCE in occupational workers was significantly higher than that in controls (11.31 vs 6.37, P < 0.001). The SCE in workers exposed to CTP and to COV was higher than that of control (10.27 and 12.58 vs 6.37) respectively. In workers exposed to CTP and COV, there were no differences of SCE for smokers and nonsmokers (P > 0.05). It is indicated that CTP and COV caused strong genetic toxicity and injury to chromosome.

Adult↗
PubMed1998

[Studies on the Ras p21 levels in workers exposed to coal tar pitch and coke oven volatiles].

To study the effects of serum p21 levels on the health of coal tar pitch(CTP) and coke oven volatiles (COV) workers recognized as the high risk population of pulmonary carcinoma, serum p21 levels among 24 cases of CTP workers, 25 cases of COV workers and 12 cases of normal control were detected with the method of Western Blotting. The results showed that the mean serum p21 level in exposed group was significantly higher than that in the normal control (366.8 vs 1270.7, P < 0.001). In the COV workers, serum p21 level in coke furnace workers was remarkably higher than that in the workers with other types of work. There were no differences for p21 among workers with different work years and between workers with or without smoking history. It indicates that CTP and COV can cause the p21 protein level increase in the occupational population.

Adult↗
PubMed2003

Bioaugmentation of tar-contaminated soils under field conditions using Pleurotus ostreatus refuse from commercial mushroom production.

The influence of the white rot fungus Pleurotus ostreatus on the degradation of selected poly- and heterocyclic aromatic hydrocarbons (referred to as polycyclic aromatic hydrocarbons [PAHs]) in soil was investigated under field conditions representing the Northern temperate zone. Pleurotus ostreatus was added to two contaminated soils in the form of homogenized refuse from the commercial production of fungus. The soils were collected from a former shipyard (the B&W soil) and underneath a former coal tar storage at an old asphalt factory in Denmark (the Ringe soil). Treatments (control, soil mixed with autoclaved sawdust medium, and soil mixed with P. ostreatus refuse) were set up in triplicate in concrete cylinders (height, 50 cm; diameter, 60 cm). The activity of P. ostreatus was measured as laccase activity and phenanthrene (PHE)- and pyrene (PYR)-degrading bacteria were enumerated. Twenty-one different PAHs were quantified. After nine weeks the concentrations of the 3-, 4-, 5-, and 6-ring PAHs in the Ringe soil were reduced by 78, 41, and 4%, respectively. These reductions corresponded with high initial laccase activity, a decrease in pH caused by the fungus, and an increase in the number of PHE- and PYR-degrading bacteria. No significant PAH degradation was observed in the B&W soil. Reasons for the difference in performance of P. ostreatus in the two soils are discussed in terms of soil histories and bioavailability. The use of P. ostreatus refuse holds promising potential for bioremediation purposes.

Bacteria↗
PubMed1990

[Studies on activated charcoal concerning the determination of sulfate in food coal-tar dyes].

It is very difficult to determine the content of sulfate in food coal-tar dye by the method designated in the "Japanese Standards of Food Additives(V)", because the endpoint on titration is difficult to gauge. We determined the concentration of sulfate in food dye nephelometrically after decolorization with charcoal but obtain different values depending on the kind of charcoal used. Because the adsorbed or eluted sulfate in the various charcoals were dispersed widely, so we tested the sulfate contents in five kinds of charcoals. It was found that all kinds of charcoals eluted or adsorbed sulfate in varying degrees. Therefore no charcoal was found to be satisfactory for use in the sulfate test.

Charcoal↗
PubMed2004

Possible genotoxic risk of combined exposure to pharmaceutical coal tar and UV-B radiation.

Goeckerman's therapy of psoriasis combines exposure to pharmaceutical coal tar and UV-B radiation. In the pilot study (15 patients had been diagnosed with psoriasis, the average time period in hospital therapy was 24 days, the average age of the patients was 29 years, 47% of them were smokers) a level of genotoxic risk from therapy was evaluated by using chromosomal aberration of peripheral lymphocytes. The study suggested the presence of an increased genotoxic risk from the therapy. The PASI scores (Psoriasis Area and Severity Index) were monitored.

Adult↗
PubMed1990

[Effect of tar and dithranol on fibrinolysis in treatment of psoriasis].

There are well known side effects of drugs for topical use due to systemic resorption. In the present study, however, 36 psoriasis blood sera were examined before and fourteen days after the coal tar and dithranol (anthralin, cignolin) therapy onset to determine D and E fibrinogen fragments. These serum levels were compared with those in 36 blood donors. The higher levels in psoriatics and their causes are being discussed.

Administration, Topical↗
PubMed1988

[Epidemiologic study of the mortality among the employees of a coal tar distillery].

A mortality study was carried out, throughout the period 1970-1984, in a cohort of 963 men who had worked for at least one year in a coal tar distillery. The observed number of deaths, 109, did not significantly differ from the expected number. Using the death rates of the local population as a reference, no excess was observed for lung cancer and for cancers of the larynx, while there was an excess for cancers of the oesophagus but non significant and for cancers of the buccal cavity and pharynx (SMR = 2.17 - p less than 0.05). A nested case-control study was carried out. From within the cohort, 5 deaths from lung cancer and 10 deaths from cancers of the buccal cavity and pharynx were defined as "cases". For each case, all the available dead controls with the same sex, year of birth, tobacco and alcohol consumption were selected from within the cohort. The odds ratios for lung cancer did not reveal any occupational risk. With regard to buccal cavity and pharyngeal cancers, the odds ratios were neither significant for a duration of exposure greater than or equal to 1 year nor for a duration greater than or equal to 5 years along with a latent period greater than or equal to 10 years. Nevertheless there is a significant OR for exposure less than or equal to 10 years (OR = 7.56) but it is near one for exposures greater than 10 years.

Adolescent↗
PubMed1985

Diflorasone diacetate ointment 0.05 percent in conjunction with UVB and tar in a modified outpatient Goeckerman regimen.

Nineteen patients with psoriasis were treated with a modified Goeckerman regimen tailored to enhance patient compliance. Treatment consisted of daily coal tar emulsion baths at bedtime, followed by the application of 0.05 percent diflorasone diacetate ointment. Patients received increasing suberythemal dosages of short ultraviolet radiation (UVB) three times weekly at our outpatient phototherapy center. The duration of therapy ranged from three to twenty-eight weeks. The average number of phototherapy treatments was twenty-nine. Eight patients had total clearing of their lesions. Of the remainder, seven had at least 75 percent clearing and one had less than 25 percent clearing of psoriasis. One patient with psoriatic erythroderma experienced no improvement. Two patients did not complete the study. There were no side effects encountered during treatment other than periodic excessive erythema. If the two patients who did not complete the study are excluded from the results, 88 percent (fifteen of the remaining seventeen) had 75 percent or greater resolution of their psoriatic eruption and 47 percent (eight of seventeen) had total clearing. This outpatient modification of the Goeckerman regimen eliminates the use of cosmetically unacceptable topical agents during working hours, promotes patient compliance, and presumably contributes to enhanced therapeutic efficacy.

Administration, Topical↗
PubMed1978

In vitro morphological transformation of cryopreserved hamster embryo cells with tobacco tar.

Cryopreserved primary cultures of Syrian golden hamster embryo cells were used as the source of target and feeder cells for in vitro bioassay of carcinogenesis. Since cultures that gave the best overall response in a preliminary test were used for the bioassay, in almost every case a range of responses was obtained. By the use of this of this bioassay system, the capacities of tobacco tar and its subfractions to induce morphological transformation were examined. Some fractions induced typical morphologically transformed colonies. A close correlation was observed between morphological transformation and bacterial mutagenesis.

Animals↗