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Biomedical subjects

S Monarca

Publications and source records attributed to S Monarca.

At least 55 records · Page 3Linked to original sources
PubMed1989

Thioethers, mutagens, and D-glucaric acid in urine of operating room personnel exposed to anesthetics.

Mutagenic hazards related to occupational exposure to nitrous oxide and enflurane was studied in the personnel of five operating rooms using a coupled environmental and biological monitoring approach. The environmental monitoring revealed air concentrations of the two anesthetics exceedings the TLVs by 10-15-fold. These values were correlated individually with the concentrations of the two anesthetics in the expired air of the exposed subjects. The biological monitoring was carried out by determining two parameters associated with mutagen exposure (urinary mutagenicity and thioethers) and a parameter associated with the enzymatic induction (D-glucaric acid) in the urine of exposed and unexposed subjects (N = 64 and N = 37, respectively). The results showed no difference in the two groups for urine mutagenicity and D-glucaric acid, but urine thioethers were significantly increased among highly exposed subjects.

Adult↗
PubMed1989

Urinary excretion of mutagens, thioethers and D-glucaric acid in workers exposed to bitumen fumes.

The authors carried out biological monitoring of the mutagenic/carcinogenic hazards associated with exposure to bitumen fumes during paving operations, analysing some biological parameters in the urine of a group of exposed workers. The urine samples were studied for mutagenicity by the Ames test and for thioethers concentration. D-Glucaric acid urine excretion was also determined to investigate the enzymatic induction potential of bitumens. Even though, in a previous environmental monitoring phase, a low content of mutagenic/carcinogenic compounds was found in bitumen and air samples, urinary mutagenicity data of exposed workers were statistically higher than those of a group of unexposed subjects. The urinary mutagenicity increased further if exposure to bitumens was associated with cigarette smoking. Thioethers were higher only in subjects exposed simultaneously to bitumens and cigarettes. D-Glucaric acid excretion did not increase significantly. The authors think that this type of coupled environmental and biological monitoring is a valid tool for a better evaluation of the mutagenic/carcinogenic exposure to bitumens or similar complex mixtures.

Air Pollutants, Occupational↗
PubMed1989

Chemical composition and genotoxic activity of petroleum derivatives collected in two working environments.

Pitch and bitumen, two complex petroleum derivative mixtures, were studied for both their chemical composition and their mutagenic/DNA damaging activity. While bitumen revealed no genotoxic effect and low polycyclic aromatic hydrocarbons (PAHs) concentration, petroleum pitch showed a high concentration of mutagenic/carcinogenic PAHs, and also an elevated mutagenic activity when assayed by the Ames test, in the presence of postmitochondrial rat liver fractions. The in vitro mutagenic activity was detectable as frameshift mutation by assaying the pitch both as an in toto mixture and after HPLC fractionation, the most polar fractions being the most active. In contrast, both derivatives showed no in vivo DNA damage in rat liver, using the DNA alkaline elution technique and the fluorometric assay of DNA unwinding.

Animals↗
PubMed1988

Effects of SO2 or NOx on toxic and genotoxic properties of chemical carcinogens. II. Short term in vivo studies.

Short term in vivo studies were performed to study biological effects of the common air pollutants SO2 or NOx and their influence on the genotoxic activities of nitrosamines. Hepatocytes and lung cells were isolated from Sprague-Dawley rats which had inhaled 50 p.p.m. of SO2 or NOx for 2 weeks. After incubating the cells for 1 h, genotoxicity was determined in hepatocytes by measuring DNA single-strand breaks induced by N-nitroso-acetoxymethylmethylamine, N-nitrosodimethylamine and N-nitrosomethylbenzylamine. Parameters of toxicity (trypan blue exclusion and leakage of serum enzymes) were determined in both liver and lung cells also following 1 h incubation. The activities of aryl hydrocarbon hydroxylase (AHH), nitrosodimethylamine demethylase (NDMA-D) and glutathione-S-transferase (GST) were determined in subcellular microsomal fractions isolated from lung and liver tissues. Finally, as a measure of overall toxicity, the activities of various serum enzymes were determined in the blood serum of the rats. It was found that the induction of DNA single-strand breaks by three nitrosamines was decreased in hepatocytes from SO2-treated animals. The viability of rat hepatocytes and of rat lung cells, as determined by trypan blue exclusion, was similar in all three treatment groups immediately after isolation, as well as after 1 h incubation with DMSO or with the nitrosamines. In contrast, the leakage of enzymes was different in hepatocytes of SO2-treated rats, since lactate dehydrogenase activity was decreased. Leakage of enzymes from the lung cells did not differ from group to group, but was lower than from hepatocytes. Foreign compound metabolizing enzymes were mainly decreased in NOx-treated animals, namely AHH, NDMA-D and GST in liver and GST in the lung. For SO2-treated animals NDMA-D was increased in liver and GST was decreased in lung. Blood serum enzyme levels were not greatly different from each other, except for lactate dehydrogenase which was elevated in SO2-exposed animals.

Air Pollutants↗
PubMed1988

Enzymatic activities of human lung tissue: relationship with smoking habits.

Twenty-two S12 preparations of surgical lung specimens obtained from smoker and non-smoker cancer patients were assayed to detect aryl hydrocarbon hydroxylase (AHH), dimethylnitrosamine demethylase (DMND), and glutathione-S-transferase (GST) activities, in both normal and neoplastic lung tissue from the same patients. Pulmonary fractions were also tested for their ability to activate some precarcinogens into mutagenic metabolites in the Ames test. Statistically significant differences were found for AHH and DMND activities between normal and neoplastic tissue of smoker patients. In addition, higher AHH activity in the neoplastic tissue of the smoker group was observed compared with that found in the non-smoker group. No differences were found for GST activity. All the lung S12 preparations were able to metabolize water-soluble bases and water-insoluble bases, derived from main-stream cigarette smoke condensate, into mutagenic agents in the Salmonella test system. However, S12 preparations from smoker group neoplastic tissues were more effective.

Aged↗
PubMed1987

Environmental monitoring of mutagenic/carcinogenic hazards during road paving operations with bitumens.

Environmental monitoring of mutagenic/carcinogenic hazards associated with occupational exposure to bitumen fumes was performed during road paving operations. Bitumen samples were collected and analysed for polycyclic aromatic hydrocarbons (PAH) content by HPLC and for mutagenicity by the Ames test. The exposure of sixteen road workers to bitumen fumes was studied. Time-weighted average values of bitumen fumes were determined by personal samplers. PAH concentration in the air and the mutagenicity of airborne particulates were also analysed. The results showed that bitumen samples contained low levels of total PAH (microgram/g) and were not mutagenic. Environmental monitoring showed a low level of exposure to bitumen fumes, which were found to contain only trace levels of PAH and not to be mutagenic. The authors suggest that these workers' exposure to mutagenic/carcinogenic agents is low.

Air Pollutants↗
PubMed1987

Enzyme induction in rat lung and liver by condensates and fractions from main-stream and side-stream cigarette smoke.

Aryl hydrocarbon hydroxylase (AHH) and dimethylnitrosamine demethylase (DMND) activities in pulmonary and hepatic tissues of male Sprague-Dawley rats were assayed following pretreatment with known inducers (benzo[a]pyrene, 3-methylcholanthrene, Aroclor 1254, phenobarbital) and with main-stream (MS) and side-stream (SS) cigarette smoke condensates and their related fractions. Biochemical assays by spectrophotofluorimetry (AHH activity) and spectrophotometry (DMND activity) and by a biological assay (Ames test) were performed to detect AHH and DMND induction. Ames test proved to be much less sensitive than the spectrophotofluorimetric analysis for AHH determination. Both main-stream and side-stream cigarette smoke condensates and some fractions, containing water-soluble bases, water-insoluble bases, and polycyclic aromatic hydrocarbons, were found to induce AHH activity in lung and liver, the lung being induced to the greatest extent. The highest levels of AHH inducibility were found for the SS-smoke condensate and related fractions. In particular, the insoluble bases fractions gave the highest induction. On the contrary, pulmonary DMND activity was not affected by pretreatment with the same materials, while hepatic DMND response was only minimally induced by Aroclor and phenobarbital treatment.

Animals↗
PubMed1987

Alcohol, tobacco, and psychoactive medicine consumption among high school students of 10 Italian towns.

Consumption of alcohol, tobacco, and psychoactive medicine among 8,276 high school students of 10 Italian towns was studied. Wine was the most widely used alcoholic beverage and was consumed daily by 16-41% of students. Alcohol use increased with age and was higher among males. Occasional or current smokers were 24-47%. Nine percent to 12% of the students admitted to having taken psychoactive medicine during the 12 months prior to the interview. Females showed the heaviest use. Relationships were found among the use of these three licit drugs.

Adolescent↗
PubMed1985

Mutagenicity studies and D-glucaric acid determination in urine of workers exposed to mineral oils.

Urine from workers of a cold-rolling steel plant exposed to mineral oils were tested for the mutagenic activity by the Salmonella/microsome assay, and for D-glucaric acid content as a measure of hepatic mixed-function oxidase activity. An occupationally unexposed group served as control. The biological monitoring phase followed an environmental phase carried out in the working environment that showed a substantially low mutagenic/carcinogenic risk for the exposed workers. Urine samples were collected before, during and after work. From the results it was observed that the urinary mutagenicity was detectable only with TA98 strain in the presence of enzymatic activation (+ S9 mix). Further addition of beta-glucuronidase did not give any enhanced mutagenic effects. There was a significant difference in urinary mutagenicity between the exposed and control workers. However, in both groups the highest mutagenicity data was found in smokers: both exposed smoking workers and smoking controls had significantly higher urine mutagenicity than the non-smoking exposed and control workers. The results suggested a synergistic effect of smoking with exposure to mineral oils: the mutagenicity of urine from exposed smokers was significantly higher than that of control smokers. There was no difference in urinary D-glucaric acid results between exposed and unexposed groups, however, smokers of both groups had a significant increase in D-glucaric acid excretion. The authors suggest that even for this workplace with its low mutagenic/carcinogenic risk, smoking could interact with the complex mixtures present in the environment, and thus modify urinary mutagenicity data.

Adult↗
PubMed1984

Mutagenic/carcinogenic hazards in a cold-rolling steel plant exposed to mineral oils: environmental monitoring phase.

A survey was carried out in a cold-rolling steel plant exposed to mineral oils to study the mutagenic/carcinogenic hazards, following a coupled environmental/biological monitoring. The present paper deals only with the environmental phase by determining polycyclic aromatic hydrocarbons (PAH) and applying a mutagenicity test (Ames test), and includes the following steps: (a) work process and environment study; (b) sampling and analysing mineral oils before and after use (PAH determination and mutagenicity analysis); (c) sampling and analysing oil mist (TWA determination, PAH determination and mutagenicity analysis). The results showed that: (1) both unused and used (recycled) mineral oils contained only trace amounts of PAH and were not mutagenic; (2) the TWA concentrations of oil mists were lower than the TLV (less than 5 mg/m3); (3) oil mists contained only trace amounts of PAH and were not mutagenic. The authors suggest that these results could be due to the moderate temperature of the oil during the work process and that there is a relationship between low PAH content and absence of mutagenicity in the oils and air samples.

Air Pollutants, Occupational↗
PubMed1984

Mutagenicity of coal tar paints used in drinking water distribution systems.

The aim of this study was to evaluate the mutagenicity of coal tar paints used for coating drinking water tanks and pipes, as a preliminary screening for potential genotoxic hazards associated with leaching of mutagens into drinking water during water storage and distribution. To this end, the Salmonella/microsome assay was performed on different fractions of two paints. The fractions were obtained using different fractionation procedures (a sequential solvent extraction and an acid-base fractionation) for removing the presence of inhibitory components. Both fractionation procedures confirmed an extraordinarily high mutagenicity in both paints, with metabolic activation, much higher than the mutagenicity of the unfractionated paints. The acid-base fractionation was more time-consuming but gave higher mutagenicity recoveries and provided information as to the general nature of the genotoxic constituents, which were concentrated in the neutral fractions. On the other hand, the sequential solvent extraction by sonication was a shorter and simpler method and permitted to reveal the presence of direct-acting mutagens. It is concluded that the application of the Salmonella/microsome assay coupled with both fractionation methods may give complementary and confirmatory data on the genotoxic properties of these coal based paints, as a screening of the potential mutagenic/carcinogenic hazards derived from these materials used in drinking water distribution systems.

Coal Tar↗
PubMed1983

Detection of mutagenic/carcinogenic compounds in unused and used motor oils.

The discharge of used motor oils in the environment poses public health problems because of the mutagenic/carcinogenic compounds in them. Among these hazardous chemicals, polycyclic aromatic hydrocarbons (PAH) are of particular interest since the carcinogenic properties of some of them are known. The authors have applied the Salmonella/microsome test, coupled with two preparation methods of samples, to motor oils of different brands, both before and after use in car petrol engines. A PAH determination method was also studied. The results showed the unused motor oils to be nonmutagenic and to contain traces of PAH, while the used motor oils of the samples taken according to both preparation methods were highly mutagenic and contained a much higher quantity of mutagenic/carcinogenic PAH.

Automobiles↗
PubMed1982

Mutagens in urine of carbon electrode workers.

Following previous work carried out in an Italian factory producing carbon electrodes and evaluating the occupational mutagenic-carcinogenic hazards, the authors studied the presence of mutagen metabolites in the urine of workers in the same factory who were exposed to petroleum coke and pitch and in the urine of a control group of unexposed workers. The urine samples were concentrated by absorption on XAD-2 columns and were tested using the Salmonella/microsome assay (strain TA 98, TA 100, TA 1535, TA 1538) with and without the addition of beta-glucuronidase and metabolizing system. The collection of urine samples was carried out twice, with an interval of 2 months; "before working time", "after working time", and also during Sunday. The results showed that (1) urine samples collected "before" occupational exposure (upon waking) or on Sunday revealed no mutagenic activity in either worker groups and (2) that the urine samples collected after or during occupational exposure revealed high mutagenic activity in the exposed workers, with a statistically significant difference (P less than 0.05) between the mean of the revertants/plate values for exposed and unexposed workers. On the basis of the previous and the present research, the authors suggest that application of the Salmonella/microsome test to work environments could offer useful and suitable tool for evaluating the health hazards due to mutagenic/carcinogenic substances from occupational exposure.

Carbon↗
PubMed1982

Application of the Salmonella mutagenicity assay and determination of polycyclic aromatic hydrocarbons in workplaces exposed to petroleum pitch and petroleum coke.

Workplaces of an Italian carbon electrode factory, exposed to petroleum pitch and petroleum coke, were studied using a coupled chemical and biological approach to evaluate occupational mutagenic/carcinogenic hazards. Analytical procedures for the determination of polycyclic aromatic hydrocarbons (PAH) and Salmonella/microsome mutagenicity tests (with TA98 and TA100 strains) were performed on both industrial ingredients (pitch and coke) and airborne particulate matter of the working environment, after fractionating by sequential Soxhlet extractions with four organic solvents of increasing polarity (benzene, chloroform, methanol and acetone). The results showed: (a) the presence of extraordinarily high PAH (carcinogenic and non-carcinogenic) contents in the benzene extracts of petroleum pitch (3.6 wt% of total PAH) and of airborne particulate samples (up to 0.35 wt% of total PAH), in correlation with very high indirect (after metabolic activation) mutagenic responses of benzene extracts with strain TA98; (b) very high indirect mutagenic responses in the other extracts of the airborne particulate samples (especially with strain TA98); (c) the production during the processing at high temperatures of directly acting mutagens (without metabolic activation) which were absent in the starting materials and their release in the air of workplaces. The comparison of chemical analytical and mutagenicity data has proved to be an interesting approach for better defining the relative health hazards due to occupational exposure to potentially mutagenic/carcinogenic petroleum products.

Air Pollutants↗
PubMed1982

Presence of benzo[a]pyrene and other polycyclic aromatic hydrocarbons in suntan oils.

Column and thin-layer chromatography followed by spectrophotofluorometry were used to determine the carcinogen benzo[a]pyrene and other polycyclic aromatic hydrocarbons (PAH) in commercial samples of four suntan iols based on mineral and/or vegetable oils liable to contain traces of PAH. The analyses showed that all the samples contained benzo[a]pyrene together with three other mutagenic, co-carcinogenic or non-carcinogenic PAH (perylene, fluoranthene and benzo]k]fluoranthene). One sample also contained the carcinogen anthanthrene. The total PAH content of the samples varied from 88 . 5 to 188 . 7 ng/g while benzo[a]pyrene levels were in the 1 . 5-4 . 7 ng/g range. The results suggest that users of suntan oils may be exposed to low levels of potentially hazardous PAH; however, in comparison with many other cosmetics that are presumably based on similar oils, suntan oils are only used intermittently and for relatively short periods.

Benzo(a)pyrene↗
PubMed1981

Evaluation of the potential carcinogenicity of paraffins for medicinal and cosmetic uses--determination of polycyclic aromatic hydrocarbons.

A previously developed method for the determination of polycyclic aromatic hydrocarbons (PAH) in purified petroleum products was applied to some fully-refined paraffin samples for cosmetic and medicinal uses of Italian Pharmacopoeia grade materials. The analytical procedure used provided identification and quantitative assay for ng/g amounts of two well-known carcinogenic PAH, namely benzo[a]pyrene and benzo[b]fluroanthene, together with five other none-carcinogenic PAH. The method is sensitive and reliable for routine analysis of PAH content in these paraffins and is compared with very rapid pharmocopoeial tests based on different criteria of quality. The data obtained showed a lack in agreement between PAH content in paraffin samples and the results of pharmacopoeial tests.

Carcinogens↗