Occupational exposure assessment of airborne chemical contaminants among professional ski waxers

BACKGROUND

Ski waxes are applied onto the skis to improve the performance. They contain different chemical substances, e.g. perfluoro-n-alkanes. Due to evaporation and sublimation processes as well as mechanically generated dust, vapours, fumes, and particulates can contaminate the workroom atmosphere. The number of professional ski waxers is increasing, but occupational exposure assessments among professional ski waxers are lacking.

OBJECTIVES

The aim was to assess exposure to airborne chemical contaminants among professional ski waxers. It was also a goal to construct a ventilation system designed for ski waxing work operations.

METHODS

Forty-five professional ski waxers were included. Personal measurements of the inhalable and the respirable aerosol mass fractions were executed in 36 different waxing cabins using Conical Inhalable Sampler cassettes equipped with 37-mm PVC filters (5 µm) and Casella respirable cyclones equipped with 37-mm PVC filters (0.8 µm), respectively. Volatile organic components were collected using Anasorb CSC charcoal tubes. To examine time trends in exposure patterns, stationary real-time measurements of the aerosol mass fractions were conducted using a direct-reading Respicon® sampler.

RESULTS

Mean aerosol particle mass concentrations of 3.1 mg·m(-3) (range: 0.2-12.0) and 6.2 mg·m(-3) (range: 0.4-26.2) were measured in the respirable and inhalable aerosol mass fractions, respectively. Real-time aerosol sampling showed large variations in particle concentrations, with peak exposures of ~10 and 30 mg·m(-3) in the respirable and the inhalable aerosol particle mass fractions, respectively. The custom-made ventilation system reduced the concentration of all aerosol mass fractions by more than 90%.

Oil mist and vapour concentrations from drilling fluids: inter- and intra-laboratory comparison of chemical analyses

OBJECTIVES

There are no recognized analytical methods for measuring oil mist and vapours arising from drilling fluids used in offshore petroleum drilling industry. To inform the future development of improved methods of analysis for oil mist and vapours this study assessed the inter- and intra-laboratory variability in oil mist and vapour analysis. In addition, sample losses during transportation and storage were assessed.

METHODS

Replicate samples for oil mist and vapour were collected using the 37-mm Millipore closed cassette and charcoal tube assembly. Sampling was conducted in a simulated shale shaker room, similar to that found offshore for processing drilling fluids. Samples were analysed at two different laboratories, one in Norway and one in the UK. Oil mist samples were analysed using Fourier transform infrared spectroscopy (FTIR), while oil vapour samples were analysed by gas chromatography (GC).

RESULTS

The comparison of replicate samples showed substantial within- and between-laboratory variability in reported oil mist concentrations. The variability in oil vapour results was considerably reduced compared to oil mist, provided that a common method of calibration and quantification was adopted. The study also showed that losses can occur during transportation and storage of samples.

CONCLUSIONS

There is a need to develop a harmonized method for the quantification of oil mist on filter and oil vapour on charcoal supported by a suitable proficiency testing scheme for laboratories involved in the analysis of occupational hygiene samples for the petroleum industry. The uncertainties in oil mist and vapour measurement have substantial implications in relation to compliance with occupational exposure limits and also in the reliability of any exposure-response information reported in epidemiological studies.

Occupational exposure to airborne perfluorinated compounds during professional ski waxing

The concentration levels of 11 perfluorinated carboxylic (PFCA) and eight sulfonic (PFSA) acids were determined in the serum of 13 professional ski waxers. The same components were also determined in workroom aerosols and in fluoro containing solid ski waxes and ski wax powders. The highest median concentration (50 ng/mL) was detected for perfluorooctanoic acid (PFOA), which is around 25 times higher than the background level. For the first time perfluorotetradecanoic acid (PFTeDA) has been found in human serum. Positive statistically significant associations between years exposed as ski waxer and seven different PFCAs were observed. The serum concentrations of the PFCAs with carbon chain lengths from C(8) to C(11) were reduced by around five to 20% on average during the eight month exposure free interval, whereas the reduction was substantially larger when the carbon chain lengths were smaller than C(8) or larger than C(11). This study links for the first time PFCAs in the ski waxers serum to exposure from the work room aerosols. Not only professional ski waxers but also the significant larger group of amateur skiers and waxers are potentially exposed to these compounds.

Using a refrigerant leak detector to monitor waste gases from halogenated anesthetics

Although halogenated gas anesthetics are indispensable in laboratory animal medicine, they are hazardous when present in the working environment. A simple technique of real-time leak detection and environmental spot monitoring can provide valuable adjunct information to current techniques of time-weighted monitoring. We investigated the minimal limit of detection of halothane, isoflurane, sevoflurane, and desflurane of a leak detector for halogenated gas refrigerants which provides a qualitative response only. We connected a container to an infrared gas analyzer to create a 135-l closed-circuit system and injected liquid halothane, isoflurane, sevoflurane, and desflurane to create calculated gas concentrations of 0.7 to 3.4 parts per million (ppm). The infrared absorbance and response of the leak detector were recorded, and a total of 5 measurements were made per concentration. The actual gas concentrations were calculated by comparison with the agent-specific absorbance standard curve. The leak detector clearly and consistently responded to halothane, isoflurane, sevoflurane, and desflurane from minimal concentrations of 2.1 +/- 0.2, 1.4 +/- 0.04, 0.8 +/- 0.04, and 1.2 +/- 0.4 ppm, respectively, as determined by infrared analysis. Although the detector does not provide numerical and time-weighted results, leak testing of equipment and repeated monitoring of the environment (spot monitoring) can provide valuable real-time information. In addition, with appropriate consideration of the methodological limitations, spot monitoring can be used to predict the likelihood of compliance with time-weighted exposure recommendations. A leak detector therefore represents a simple, effective, and inexpensive instrument for monitoring the leakage of halogenated anesthetic gases from equipment and into the working environment.

Determination of airborne trialkyl and triaryl organophosphates originating from hydraulic fluids by gas chromatography–mass spectrometry

Methodology for personal occupational exposure assessment of airborne trialkyl and triaryl organophosphates originating from hydraulic fluids by active combined aerosol and vapor sampling at 1.5L/min is presented. Determination of the organophosphates was performed by gas chromatography-mass spectrometry. Combinations of adsorbents (Anasorb 747, Anasorb CSC, Chromosorb 106, XAD-2 and silica gel) with an upstream cassette with glass fiber or PTFE filters and different desorption/extraction solvents (CS(2), CS(2)-dimethylformamide (50:1, v/v), toluene, dichloromethane, methyl-t-butyl ether and methanol) have been evaluated for optimized combined vapor and aerosol air sampling of the organophosphates tri-isobutyl, tri-n-butyl, triphenyl, tri-o-cresyl, tri-m-cresyl and tri-p-cresyl phosphates. The combination of Chromosorb 106 and 37 mm filter cassette with glass fiber filter and dichloromethane as desorption/extraction solvent was the best combination for mixed phase air sampling of the organophosphates originating from hydraulic fluids. The triaryl phosphates were recovered solely from the filter, while the trialkyl phosphates were recovered from both the filter and the adsorbent. The total sampling efficiency on the combined sampler was in the range 92-101% for the studied organophosphates based on spiking experiments followed by pulling air through the sampler. Recoveries after 28 days storage were 98-102% and 99-101% when stored at 5 and -20 degrees C, respectively. The methodology was further evaluated in an exposure chamber with generated oil aerosol atmospheres with both synthetic and mineral base oils with added organophosphates in various concentrations, yielding total sampling efficiencies in close comparison to the spiking experiments. The applicability of the method was demonstrated by exposure measurements in a mechanical workshop where system suitability tests are performed on different aircraft components in a test bench, displaying tricresyl phosphate air concentrations of 0.024 and 0.28 mg/m(3), as well as during aircraft maintenance displaying tri-n-butyl phosphate air concentrations of 0.061 and 0.072 mg/m(3).

Occupational exposure to hexabromocyclododecane at an industrial plant

Occupational exposure to hexabromocyclododecane (HBCD) among workers at an industrial plant producing expandable polystyrene (PS) added HBCD as flame retardant has been assessed in the present study. Airborne dust samples were collected near the breathing zone of 10 male workers during three 8-h work shifts. The HBCD concentrations in the airborne dust varied from 0.2 to 150 microg/m3 (mean 12.2 and median 2.1 microg/m3). Two serum samples were obtained from each of the workers. The mean serum concentration was 190 ng/g lipids; the median was 101 ng/g lipids (range 6 to 856 ng/g lipids). HBCD was not detected above 1 ng/g lipids (LOD) in any samples from persons in a reference group with no occupational exposure to HBCD. The contribution of gamma-HBCD to the total HBCD serum concentration was notably high (39%) compared to what has usually been observed in biological samples. There was no clear correlation of serum levels with average HBCD concentrations in the airborne dust samples collected near the subjects' breathing zone. The elevated exposure levels reported in this study compared to urban air and serum levels in general populations suggest that further and more detailed exposure assessment studies should be initiated in industries where HBCD is applied.

Characterization of Adducts Formed in the Reaction of Glutaraldehyde with 2‘-Deoxyadenosine

Glutaraldehyde (1,5-pentanedial) is a widely used industrial chemical that has been found to be mutagenic in bacteria and mammalian cells. In this study, we examined the reaction of glutaraldehyde with 2'-deoxyadenosine and calf thymus DNA in aqueous buffered solutions. The 2'-deoxyadenosine adducts were isolated by reversed phase HPLC and characterized by their UV absorbance and 1H and 13C NMR spectroscopic and mass spectrometric features. The reaction produced three major adducts. The adduct dA567 was derived from two 2'-deoxyadenosine units bound together with a piperidine unit, and its yield was 10.4%. The carbons of the piperidine ring originated from glutaraldehyde, whereas the nitrogen of the ring originated from the exocyclic amino group of one of the 2'-deoxyadenosine units. The adduct dA451d (yield 0.6%) was similar in structure to dA567, but one of the deoxyribose moieties from 2'-deoxyadenosine was missing. The third adduct, dA334, consisted of a hydroxy-tetrahydropyridine moiety derived from glutaraldehyde and N6 of 2'-deoxyadenosine (yield 4.0%). Furthermore, LC-ESI-MS/MS analysis of the reaction mixture revealed the formation of compounds with ion peaks of m/z = 352. None of these compounds were sufficiently stable for preparative isolation. They were tentatively identified as a pair of diastereomers of 2,6-dihydroxypiperidine derivatives, which are likely precursors to dA334. Plausible mechanisms for the formation of the adducts are presented. In the reaction of glutaraldehyde with single and double stranded calf thymus DNA, the dA334 adduct was formed.

Determination of the dialdehyde glyoxal in workroom air—development of personal sampling methodology

The dialdehyde glyoxal (ethanedial) is an increasingly used industrial chemical with potential occupational health risks. This study describes the development of a personal sampling methodology for the determination of glyoxal in workroom air. Among the compounds evaluated as derivatizing agents; N-methyl-4-hydrazino-7-nitrobenzofurazan (MNBDH), 1,2-phenylenediamine (OPDA), 1-dimethylaminonaphthalene-5-sulfonylhydrazine (dansylhydrazine, DNSH) and 2,4-dinitrophenylhydrazine (DNPH), DNPH was the only reagent that was suitable. Several different samplers were evaluated for sampling efficiency of glyoxal in workroom air using DNPH as derivatizing agent; in-house DNPH coated silica particles packed in two different types of glass tubes, impingers containing acidified DNPH solution, filter cassettes containing glass fibre filters coated with DNPH, a commercially available solid phase cartridge sampler originally developed for formaldehyde sampling (Waters Sep-Pak DNPH-silica cartridge), and the commercially available SKC UMEx 100 passive sampler originally developed for formaldehyde sampling. Aldehyde atmospheres for sampler evaluation were generated with an in-house made vapour atmosphere generator coupled to a sampling unit, with the possibility of parallel sampling. The resulting glyoxal-DNPH derivative was determined using both LC-UV and LC-APCI-MS with negative ionization. By far, the highest recovery of glyoxal was obtained employing one of the in-house DNPH coated silica samplers (93%, RSD = 3.6%, n = 12).

Airborne exposure and biological monitoring of bar and restaurant workers before and after the introduction of a smoking ban

The aims were to assess the impact of a total smoking ban on the level of airborne contaminants and the urinary cotinine levels in the employees in bars and restaurants. In a follow up design, 13 bars and restaurants were visited before and after the implementation of a smoking ban. Ninety-three employees in the establishments were initially included into the study. The arithmetic mean concentration of nicotine and total dust declined from 28.3 microg m(-3) (range, 0.4-88.0) and 262 microg m(-3) (range, 52-662), respectively, to 0.6 microg m(-3) (range, not detected-3.7) and 77 microg m(-3) (range, not detected-261) after the smoking ban. The Pearson correlation coefficient between airborne nicotine and total dust was 0.86 (p < 0.001; n = 48). The post-shift geometric mean urinary cotinine concentration declined from 9.5 microg g(-1) creatinine (cr) (95% CI 6.5-13.7) to 1.4 microg g(-1) cr (95% CI 0.8-2.5) after the ban (p < 0.001) in 25 non-snuffing non-smokers. A reduction from 1444 microg g(-1) cr (95% CI 957-2180) to 688 microg g(-1) cr (95% CI 324-1458) was found (p < 0.05) in 29 non-snuffing smokers. The urinary cotinine levels increased from 11.7 microg g(-1) cr (95% CI 7.0-19.6) post-shift to 21.9 microg g(-1) cr (95% CI 13.3-36.3) (p < 0.01) in the next morning in 24 non-snuffing non-smokers before the smoking ban. A substantial reduction of airborne nicotine and total dust was observed after the introduction of a smoking ban in bars and restaurants. The urinary cotinine levels were reduced in non-smokers. The decline found in smokers may suggest a reduction in the amount of smoking after intervention. In non-smokers cotinine concentrations were higher based on urine sampled the morning after a shift than based on urine sampled immediately post-shift.

Occupational exposure to airborne solvents during nail sculpturing

This study describes occupational exposure to acrylates and other solvents during nail sculpturing, including comparative measurements of the exposure using four different sculpturing methods: The acrylic method, the UV-gel method, the acrylic powder method and the resin method. Thirty-two nail technicians working in 22 different salons participated in the study. In total, 92 measurements were performed, comprising 70 solvent measurements and 22 measurements of ethyl 2-cyanoacrylate. The solvents most frequently present in all samples were acetone, ethyl acetate, toluene and n-butyl acetate, measured in 96%, 94%, 91% and 81% of the samples, respectively. The study shows that the overall solvent exposure was low, with all measurements calculated as the additive effect (n = 70) below 20% of the OEL (arithmetic mean 0.06 and range 0.01-0.19). No statistically significant difference between sculpturing methods were observed (p = 0.05).

Reaction of Glyoxal with 2‘-Deoxyguanosine, 2‘-Deoxyadenosine, 2‘-Deoxycytidine, Cytidine, Thymidine, and Calf Thymus DNA: Identification of DNA Adducts

Glyoxal (ethanedial) is an increasingly used industrial chemical that has been found to be mutagenic in bacteria and mammalian cells. In this study, the reactions of glyoxal with 2'-deoxyguanosine, 2'-deoxyadenosine, 2'-deoxycytidine, cytidine, thymidine, and calf thymus DNA have been studied in aqueous buffered solutions. The nucleoside adducts were isolated by reversed-phase liquid chromatography and characterized by their UV absorbance and 1H and 13C NMR spectroscopic and mass spectrometric features. The reaction with 2'-deoxyguanosine gave one adduct, the previously known 3-(2'-deoxy-beta-D-erythro-pentofuranosyl)-5,6,7-trihydro-6,7-dihydroxyimidazo[1,2-a]purine-9-one adduct. The reaction of 2'-deoxyadenosine with glyoxal resulted in the formation of a previously not reported N6-(hydroxyacetyl)-2'-deoxyadenosine adduct. In the reaction of glyoxal with 2'-deoxycytidine and cytidine at neutral conditions and 37 degrees C, 5-hydroxyacetyl pyrimidine derivatives were obtained. When the cytidine reaction was performed at pH 4.5 and 50 degrees C, the 5-hydroxyacetyl derivative of uridine was formed through deamination of cytidine-glyoxal. Adducts in the thymidine reaction could not be detected. In the reaction of glyoxal with calf thymus DNA, the 2'-deoxyguanosine-glyoxal and 2'-deoxyadenosine-glyoxal adducts were obtained, the former being the major adduct.

Air formaldehyde and solvent concentrations during surface coating with acid-curing lacquers and paints in the woodworking and furniture industry

An investigation of contemporary exposure to formaldehyde and organic solvents has been carried out during surface coating with acid-curing lacquers and paints in the Norwegian woodworking and furniture industry over a period of 3 years. The investigation covered 27 factories of different sizes and with different types of production, and totally 557 parallel formaldehyde and solvent samples were collected. The formaldehyde concentration (geometric mean) was 0.15 ppm (range 0.01-1.48 ppm) with about 10% of the samples exceeding the Norwegian occupational exposure limit of 0.5 ppm. The solvent concentration as additive effect (geometric mean) was 0.13 (range 0.0004-5.08) and about 5% of the samples exceeded the Norwegian occupational exposure limit. The most frequently occurring solvents from acid-curing lacquers were n-butyl acetate, ethanol, ethyl acetate and 1-butanol, which were found in 88-98% of the samples. Toluene, n-butyl acetate and 1-butanol were the only solvents with maximum concentrations exceeding their respective occupational exposure limits. Curtain painting machine operators were exposed to the highest concentrations of both formaldehyde (geometric mean 0.51 ppm, range 0.08-1.48 ppm) and organic solvents (additive effect, geometric mean 1.18, range 0.02-5.08). Other painting application work tasks such as automatic and manual spray-painting, manual painting and dip painting, showed on average considerably lower concentrations of both formaldehyde (geometric means 0.07-0.16 ppm) and organic solvents (additive effect, geometric mean 0.02-0.18). Non-painting work tasks also displayed moderate concentrations of formaldehyde (geometric means 0.11-0.17 ppm) and organic solvents (additive effect, geometric mean 0.04-0.07).

Comparison of sampling efficiency and storage stability on different sorbents for determination of solvents in occupational air

This study describes the sampling efficiency and storage stability of compounds typically present in occupational atmospheres on the sorbents Anasorb CSC, Anasorb 747, and Chromosorb 106. The selection of compounds included in the study contained aliphatic and aromatic hydrocarbons, alcohols, esters, glycol ethers, ketones, and halogenated compounds, thus representing a wide range of chemical and physical properties. The different sorbent tubes were simultaneously exposed to the selected compounds as three different mixtures of solvent vapours in air, and storage both at room temperature and at -22 degrees C was investigated. The sorbent tubes were stored and analyzed at two different laboratories. The sampling efficiencies of all the investigated compounds were excellent on Anasorb CSC and Anasorb 747, while Chromosorb 106 did not give such good results for the most volatile compounds under study. The room temperature storage stability on Chromosorb 106, however, was good for all compounds, although formation of artefacts was observed during storage, a disadvantage that was substantially reduced by storage at -22 degrees C. The room temperature storage stability on Anasorb CSC was good for all compounds except some of the ketones. The room temperature storage stability of these ketones, especially cyclohexanone and 2-butanone, was much better on Anasorb 747, which still showed the same excellent storage stability for the remaining compounds. When stored in a freezer, the storage stability of all compounds, including the ketones, was very good on all sorbents. Among the sorbents under study, Anasorb 747 appears to be the most suitable all-round sorbent for monitoring volatile compounds in occupational air, with satisfactory capabilities regarding both sampling efficiency and storage stability.

Occupational exposure to fluorinated hydrocarbons during refrigeration repair work

This study describes refrigeration repair workers' occupational exposures to halogenated refrigerants, focusing on difluorochloromethane (HCFC 22), tetrafluoroethane (HFC 134a) and a mixture of tri-, tetra- and pentafluoroethane (R404A) in 30 work operations. Unlike earlier reported studies, the present study includes working procedures involving welding in order to measure possible occupational exposure to decomposition products. The measurements included hydrogen fluoride (HF), hydrogen chloride (HCl), phosgene (COCl2) and volatile organic compounds (VOC). The exposures were assessed during work operations on small-scale cooling installations like refrigerators and freezers. The repair workers' occupational exposures to refrigerants were moderate, and the major part of the exposures were associated with specific working procedures lasting for relatively short periods of time (<20 min). During these exposure events the concentrations were occasionally high (up to 42434 mg m(-3)). Although welding operations lasted only for short periods of time, HF was detected in 9 out of 15 samples when HCFC 22, HFC 134a or R404A had been used. Hydrogen chloride was detected in 3 out of 5 samples in air polluted with HCFC 22. Phosgene was not detected. A large number of VOCs in various concentrations were found during welding. Except for the applied refrigerants, halogenated compounds were only found in one sample.

Solvent exposures at shoe factories and workshops in Hebron City, West Bank

Exposure to organic solvents has been reported to increase the risks for acute and chronic health effects among shoe industry workers. In developing countries, protection against chemical exposures is often not provided. The study was conducted to identify working conditions and estimate the concentrations of organic solvents used in shoe factories and workshops in Hebron City. Personal interviews containing questions related to personal protective equipment (PPE) were used to identify working conditions, and samples collected from factories and workshops were analyzed using gas chromatography. Geometric means (GMs) were calculated for the solvents. Six major organic solvents were detected in the factories. Acetone (GM = 51.5 mg/m3, GSD = 3.82) was common in gluing tasks. Dichloromethane (GM = 47 mg/m3, GSD = 2.62) was common in cleaning tasks. Heptane, methylethyl ketone, n-hexane, and toluene were common in gluing tasks. Four major organic solvents were detected in the workshops: acetone (GM = 32.3 mg/m:3, GSD = 6.33), toluene (GM = 70.3 mg/m3, GSD = 3.06), n-hexane (GM = 19.4 mg/m3:, GSD = 2.65), and methylethyl ketone (GM = 130 mg/mM3, GSD = 1.5). 81% of the factory workers had never used respiratory protective equipment, and 92% had never used work clothes. 97% of the workers in the workshops had never used respiratory protective equipment, 94% had never worn gloves, and 90% had never used work clothes. Exposures to solvents in the absence of personal Protective equipment, tasks barriers, and mechanical ventilation can adversely affect health.

Determination of 1-(2-methoxyphenyl)piperazine derivatives of isocyanates at low concentrations by temperature-programmed miniaturized liquid chromatography

A temperature-programmed packed capillary LC method with large-volume injection on-column focusing has been developed for screening and determination of 1-(2-methoxyphenyl)piperazine derivatives of airborne toluene-2,4-diisocyanate, toluene-2,6-diisocyanate, hexamethylenediisocyanate and methylenebisphenyl-4,4-diisocyanate, based on sampling methods described in MDHS 25/3. Injection volumes up to 100 microl were successfully loaded onto the 250x0.32 mm I.D. capillary column packed with 3 microm Hypersil ODS particles. The isocyanate derivatives were loaded at 10 degrees C and eluted by a three-step temperature program starting at 10 degrees C for 10 min, followed by a temperature ramp of 2.5 degrees C min(-1) to 45 degrees C and then 9.9 degrees C min(-1) to 90 degrees C. The mobile phase consisted of acetonitrile-acetate buffer (3% triethylamine, pH 4.5) (45:55, v/v). The isocyanate derivatives were dissolved in acetonitrile-acetate buffer (3% triethylamine, pH 4.5) (30:70, v/v) to achieve sufficient focusing. The concentration limit of detection of the individual derivatives utilizing an "U" shaped flow cell with a 8.0 mm light path and an injection volume of 100 microl was 44, 87, 43 and 210 pg ml(-1) for toluene-2,6-diisocyanate, hexamethylenediisocyanate, toluene-2,4-diisocyanate and methylenebisphenyl-4,4-diisocyanate, respectively. Within the investigated concentration range, 10-500 ng ml(-1), the linear calibration curves gave correlation coefficients ranging from 0.994 to 0.998. The repeatability of the method with regard to retention time and peak height ranged from 0.3 to 1.1% and 1.1 to 2.3% (n=9) relative standard deviation, respectively. The average recovery of the method, with regard to toluene-2,4-diisocyanate, was 97.7+/-1.6% (n=9).