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Biomedical subjects

J O Levin

Publications and source records attributed to J O Levin.

At least 37 records · Page 2Linked to original sources
PubMed1999

Exposure to polycyclic aromatic hydrocarbons and genotoxic effects on nonsmoking Swedish road pavement workers.

OBJECTIVES: The objective of this study was to investigate exposure to polycyclic aromatic hydrocarbons (PAH) from asphalt fumes among Swedish road pavement workers and determine whether any effects could be detected with genotoxic tests. METHODS: The study included 28 nonsmoking road pavers and 30 nonsmoking referents. The concentration of PAH was determined in the breathing zone of the road pavers. 1-Hydroxypyrene was analyzed before and after shifts of asphalt work and during the afternoon for referents. Sister chromatid exchanges (SCE) and micronuclei (MN) were determined in peripheral lymphocytes. RESULTS: Several 3- or 4-ring PAH were found, and the analysis indicated that they occurred in bitumen fumes rather than in traffic fumes. The average total concentration of PAH was 2.3 (range 0.2-23.8) microg/m3. The concentration of 1-hydroxypyrene in urine was higher for the road pavers than for the referents, but there was no significant difference between the pre- and postshift values of the road pavers. The road pavers had no significant increase in SCE or MN. CONCLUSIONS: The study showed that Swedish road pavers have an increased exposure to PAH from bitumen fumes, but no genotoxic effects could be detected by SCE or MN tests.

Adult↗
PubMed1997

Terpene exposure and respiratory effects among workers in Swedish joinery shops.

OBJECTIVES: Exposure to monoterpenes (alpha-pinene, beta-pinene and delta 3-carene) in joinery shops was studied in Sweden during the processing of Scot's pine, and the acute respiratory effects among the employees were evaluated. METHODS: A cross-sectional study of 38 workers was carried out in 4 joinery shops. The investigation included personal air sampling of monoterpenes, biological monitoring of metabolites of alpha-pinene in the workers' urine, interviews following a standardized questionnaire, and dynamic spirometry. RESULTS: The personal exposure to monoterpenes in the joinery shops was 10-214 mg/m3. The correlation (correlation coefficient = 0.69) between exposure to alpha-pinene and verbenols (metabolites from alpha-pinene) in urine was relatively good. No acute effects on forced vital capacity or forced expiratory volume during 1 s were detected. The workers had significantly reduced preshift lung function values when compared with the values of a local reference group, even when smokers and ex-smokers were excluded. CONCLUSIONS: Personal exposure to the monoterpenes alpha-pinene, and delta 3-carene in joinery shops may exceed the present Swedish occupational exposure limit of 150 mg/m3 during the winter season when workroom air is commonly recirculated. The determination of metabolites of alpha-pinene (verbenols) in urine can be used as an index of exposure to fumes released during wood-treating processes. The results from the lung function tests indicate chronic rather than acute reactions in the airways. The fact that there were no major changes in lung function over a workshift indicates chronic reaction in the airways.

Adult↗
PubMed1996

Gas chromatographic-mass spectrometric identification of metabolites from alpha-pinene in human urine after occupational exposure to sawing fumes.

Three metabolites from alpha-pinene (two diols and an alcohol with an aldehyde group) have been identified in human urine after occupational exposure to sawing fumes from pine. Urine was enzymatically hydrolyzed, cleaned up on a C18 micro-column and the metabolites were identified by GC-MS using electron impact (70 eV) and chemical ionization with ammonia or isobutane as the reagent gas. Analysis of underivatized metabolites was performed using a capillary column with a semi-polar phase and trimethylsilylated derivatives were analyzed using a non-polar phase.

Bicyclic Monoterpenes↗
PubMed1996

Terpene exposure and respiratory effects among sawmill workers.

OBJECTIVES: This study was performed to evaluate exposure to terpenes in sawmills and to study the acute effects on lung function and the respiratory tract of exposed laborers. METHODS: The relationships between personal exposure to sawing fumes, assessed by air sampling, and terpene metabolites in urine were studied. The association between exposure to terpenes and acute effects on lung function was studied for 48 workers. The reactivity to methacholine within the study population was investigated. Variation in acute subjective respiratory symptoms during a workshift was evaluated by interviewing the employees before and after work, following a standardized questionnaire. RESULTS: Personal exposure to terpenes in the sawmills was 11-158 mg. m-3. The correlation (correlation coefficient = 0.84) between exposure to alpha-pinene and the concentration of verbenols (metabolites from alpha-pinene) in urine was good. No acute effects on forced vital capacity or forced expiratory volume during 1 s were detected. A decrease in carbon monoxide lung diffusing capacity after a workshift was detected. Workers with > or = 5 years of sawmill employment showed a higher reactivity to methacholine than those with < 5 years. Eye irritation increased during a workday. CONCLUSIONS: Personal exposure to monoterpenes during a workshift sometimes exceeds the present Swedish limit value. The results show that verbenols in urine can be used as a biological exposure index of sawing fumes. Exposure in sawmills can cause an acute decrease in diffusing capacity. Workers with < or = 5 years of employment showed increased bronchial reactivity.

Acute Disease↗
PubMed1995

Occupational PAH exposure: urinary 1-hydroxypyrene levels of coke oven workers, aluminium smelter pot-room workers, road pavers, and occupationally non-exposed persons in Sweden.

Polycyclic aromatic hydrocarbon (PAH) levels in air, and worker urinary 1-hydroxypyrene levels were studied in a coke oven, a Söderberg aluminium smelter pot-room, and during road-paving. Increased PAH exposure was shown to cause increased 1-hydroxypyrene excretion. Road-paving gave low PAH exposure, but resulted in a detectable elevated urinary 1-hydroxypyrene level. Background urinary 1-hydroxypyrene levels in office workers were determined, and a statistically significant difference between smokers and non-smokers was observed. It is suggested that urinary 1-hydroxypyrene can be used as biological exposure index for PAH exposure.

Air Pollutants, Occupational↗
PubMed1994

Exposure to low molecular polyamines during road paving.

Fatty amine wetting agents are used to increase adhesion in bitumen emulsions used in road paving, but commercial fatty amine products are contaminated with low molecular polyamines and alkanol polyamines which are released from the hot bitumen during paving. Polyamines and alkanol polyamines are known to cause eye and respiratory tract irritation and skin sensitization. The exposure of road pavers to ethylenediamine, diethylenetriamine, triethylenetetramine, tetraethylenepentamine, hydroxyethylethylenediamine, hydroxyethyldiethylenetriamine, monoethanolamine and diethanolamine was studied, since most of these compounds were found in the products used. Personal and static air sampling was performed during road paving. A highly sensitive measurement technique utilizing naphthylisothiocyanate-coated sorbents and filters was used. Exposure was found to be in the range < 0.02-0.5 mg m-3, as total concentration of low molecular polyamines and alkanol polyamines. Since the polyamines and alkanol polyamines in question are highly irritating they may contribute to the symptoms experienced by the road pavers.

Air Pollutants, Occupational↗
PubMed1992

Renal elimination of verbenols in man following experimental alpha-pinene inhalation exposure.

The renal elimination of verbenols after experimental exposure to (+) and (-)alpha-pinene was studied in humans following exposure to 10, 225, and 450 mg.m-3 terpene in an exposure chamber. The pulmonary uptake was about 60%. About 8% was eliminated unchanged in exhaled air. Depending on the exposure level, about 1%-4% of the total uptake was eliminated as cis- and trans-verbenol. Most of the verbenols were eliminated within 20 h after a 2-h exposure. The renal excretion of unchanged alpha-pinene was less than 0.001%.

Adult↗
PubMed1991

Assessment of genotoxic exposure in Swedish coke-oven work by different methods of biological monitoring.

This study evaluated the results of several biological methods used simultaneously to monitor coke-oven work. Blood samples from 44 male coke-oven workers and 48 male referents, matched for age and smoking/snuff consumption, were examined for cytogenetic damage in lymphocytes. Urinary thioether excretion was determined for 62, and urine mutagenicity for 31, of the subjects, who followed a standardized diet during the urine sampling. Exposure to polycyclic aromatic hydrocarbons varied with work task, the ambient air levels of benzo[a]pyrene sometimes exceeding 5 micrograms/m3. Cytogenetic damage, urine mutagenicity, and thioether excretion did not differ between the groups. The smokers, however, had significantly higher sister chromatid exchange frequencies, urine mutagenicity, and thioether excretion than the nonsmokers. The absence of biological indications of genotoxic exposure was unexpected and indicates that the studied methods are not adequate to assess the carcinogenic risks of Swedish coke-oven workers.

Adult↗
PubMed1990

Identification of cis- and trans-verbenol in human urine after occupational exposure to terpenes.

Urine from sawmill workers exposed to alpha-pinene, beta-pinene and delta-3-carene was collected and hydrolyzed with beta-glucuronidase at pH 5.0 for 24 h at 37 degrees C. After hydrolysis the urine was cleaned on a SEP-PAK C18 cartridge. The cartridge was eluted with n-heptane. The eluate was injected onto a gas chromatograph equipped with a 25-m (0.32-mm ID) SP-1000 capillary column. The major peak in the chromatogram was identified by GC-MS as trans-verbenol by electron impact at 70 eV. cis-Verbenol was also identified. These metabolites could not be detected in non-hydrolyzed urine from the exposed workers or in hydrolyzed urine from an unexposed individual. The recoveries of the verbenols from hydrolyzed urine were in the range of 85 to 94% and the metabolites were stable both in urine and in n-heptane after sample cleaning at -20 degrees C for at least 12 weeks. We suggest that these metabolites are formed from alpha-pinene by hydroxylation.

Bicyclic Monoterpenes↗
PubMed1989

Monitoring of parts-per-billion levels of formaldehyde using a diffusive sampler.

A diffusive sampler for formaldehyde originally designed for use in personal monitoring of worker exposure has been evaluated for static measurement of low formaldehyde levels in indoor air. The sampler consists of a 37-mm glass fiber filter impregnated with 2,4-dinitrophenylhydrazine and phosphoric acid and mounted in a polystyrene filter cassette. Formaldehyde is sampled by controlled diffusion and subsequent hydrazone formation on the filter. The hydrazone is eluted from the filter with acetonitrile and analyzed by liquid chromatography and a UV detector. The diffusive sampler was evaluated for static (area) sampling in several industries, offices, and homes with formaldehyde levels of 6-200 ppb. Results from diffusive samplers were compared with results from pumped samplers. Even at low wind velocities (less than 0.01 m.s-1) there was good agreement between pumped and diffusive samples. The sensitivity will be 1 ppb in a 24-h sample, making the sampler especially useful for indoor air monitoring of low formaldehyde levels.

Air Pollutants, Occupational↗
PubMed1988

Determination of specific mercapturic acids in human urine after experimental exposure to toluene or o-xylene.

Volunteers were exposed to toluene and o-xylene for 4 h at 300 mg/m3 and 350 mg/m3, respectively, in an exposure chamber. Urine voided during and after the exposure was analysed for S-benzyl-N-acetylcysteine (toluene mercapturic acid) and S-(o-methylbenzyl)-N-acetylcysteine (o-xylene mercapturic acid). The amount of S-(o-methylbenzyl)-N-acetylcysteine found in urine after exposure corresponded to a metabolic yield of less than about 0.01% of the total uptake. No S-benzyl-N-acetylcysteine was found. Thus, determination of specific mercapturic acids after exposure to toluene or o-xylene can hardly be used for genotoxic monitoring.

Acetylcysteine↗
PubMed1986

A procedure for the analysis of S-benzyl-N-acetylcysteine and S-(o-methylbenzyl)-N-acetylcysteine in human urine.

Analytical methods for mercapturic acids, the end-products of glutathione metabolism of the industrial solvents toluene and o-xylene (i.e., S-benzyl-N-acetylcysteine and S-(o-methylbenzyl)-N-acetylcysteine), added to human urine have been developed. The sensitivity is 2 ng/microliter (R.S.D. = +/- 13%) and 1 ng/microliter (R.S.D. = +/- 6.4%) urine for S-benzyl-N-acetylcysteine and S-(o-methylbenzyl-N-acetylcysteine, respectively, when using the h.p.l.c. method. The corresponding sensitivities for the g.l.c.-mass spectrometric method are 0.5 and 0.3 ng/microliter urine, respectively.

Acetylcysteine↗
PubMed1983

Monitoring 1,6-hexamethylene diisocyanate in air by chemosorption sampling.

Monitoring 1,6-hexamethylene diisocyanate in air by chemosorption sampling. Scand j work environ health 9 (1983) 497-503. A sampling procedure for 1,6-hexamethylene diisocynate (HDI) in air is described. The diisocyanate is trapped on a chemosorption tube containing 9-(N-methylaminomethyl)anthracene adsorbed on Amberlite XAD-2. Recoveries in the laboratory experiments were 81-91%. The chemosorption technique was evaluated in the field by measurements at two different factories using HDI as a hardener in two-component paints for vehicle refinishing. Simultaneous sampling with a fritted-glass bubbler and by the chemosorption technique showed equal collection efficiencies for HDI when 3.5- to 22-1 air samples were used. For air samples exceeding 20 1 the collection efficiency of the fritted-glass bubbler decreased. Several additional peaks appeared in the chromatograms from the fritted-glass bubblers. Statistical treatment of the data showed that these peaks are closely related to the amount of HDI.

Air Pollutants, Occupational↗
PubMed1981

Chemosorption sampling and analysis of formaldehyde in air. Influence on recovery during the simultaneous sampling of formaldehyde, phenol, furfural and furfuryl alcohol.

A method based on trapping formaldehyde on a 2,4-dinitrodinitrophenylhydrazine-coated porous polymer (Amberlite XAD-2) was evaluated for air sampling in occupational environments. The aldehyde is converted to its 2,4-dinitrophenylhydrazone on the adsorbent. The influence of some organic compounds which often occur together with formaldehyde-furfural, phenol and furfuryl alcohol--was studied. The results show that the method allows the sampling of formaldehyde in the range 0.01--1.0 mg/m3 of air, based on a 3-1 (15 min) sample and a coating of 1%. Furfural, phenol, and furfuryl alcohol do not interfere and may be conveniently sampled at the same time. Formaldehyde and furfural hydrazones were analyzed by high-performance liquid chromatography, phenol and furfuryl alcohol by gas chromatography.

Air Pollution↗