Håkan Westberg

Personal air sampling and analysis of polybrominated diphenyl ethers and other bromine containing compounds at an electronic recycling facility in Sweden

Brominated flame retardants (BFRs) have been used extensively and are considered ubiquitous contaminants. To evaluate exposure to brominated flame retardants within an electronic recycling facility personal air monitoring was done during a two year period. A total of 22 polybrominated diphenyl ethers (PBDEs) and 2 other bromine containing organic compounds have been analysed and evaluated in 17 personal air samples. The most abundant congeners of PBDE was #209 (<0.7-61 ng m(-3)), #183 (<0.1-32 ng m(-3)) indicating the use of the commercial octaBDE mixture, followed by PBDE #99 and #47 (<1.3-25 and <0.9-16 ng m(-3), respectively). The second most abundant peak in the chromatogram from all samples was identified as 1,2-bis(2,4,6-tribromophenyxy)ethane (BTBPE) in the concentration range <0.6-39 ng m(-3) (semi-quantitatively calculated against PBDE #191). A second bromine containing compound was also detected, structurally similar to decabromodiphenyl ethane (DeBDethane), however no definite identification could be made. The air samples were also evaluated on a work exposure category basis. The workers represented three different categories: dismantlers, other workers and unexposed. There was a significant difference (p < 0.05 with the Mann-Whitney test) among the dismantlers and the unexposed categories for PBDE congeners #47, #100, #99, #154; #153, #183, #209 and BTBPE. Another observation was that the air concentrations of PBDEs and BTBPE in the breathing zone were negatively correlated (p < 0.05) to the amount of recycled material (in kg). The present work shows that the exposure to brominated flame retardants varied within the electronic facility and that further research is needed to evaluate how the exposure differs with different products being dismantled as well as how the bioavailability of the different BFRs to humans is related to particle exposure.

Health effects of working in pulp and paper mills : exposure, obstructive airways diseases, hypersensitivity reactions, and cardiovascular diseases

Workers in the pulp and paper industry are exposed to different substances, such as hydrogen sulfide and other reduced sulfur compounds, chlorine, chlorine dioxide, sulfur dioxide, terpenes, and paper dust. The exposure level depends on the process, i.e., sulfite, sulfate, groundwood, bleachery, or paper production. Hitherto, exposures have been poorly described and more studies are certainly needed. Workers with repeated exposure peaks to chlorine, e.g., bleachery workers, seem to have an impaired lung function and an increased prevalence of respiratory symptoms. Exposure to high levels of paper dust, (> 5 mg/m3) causes impaired lung function. Therefore, exposure to respiratory irritants is an important, and probably overlooked, occupational risk among certain groups of pulp and paper workers. Some studies indicate that sulfate workers with high exposure to reduced sulfur compounds have an increased mortality due to ischemic heart disease. However, before any definite conclusions can be drawn, the impact of important confounders, such as shift-work and smoking habits have to be further evaluated.

Inhalation Exposure to Fluorotelomer Alcohols Yield Perfluorocarboxylates in Human Blood

Levels of perfluorinated carboxylates (PFCAs) in different environmental and biological compartments have been known for some time, but the routes of exposure still remain unclear. The opinions are divergent whether the exposure to general populations occurs mainly indirect through precursor compounds or direct via PFCAs. Previous results showed elevated blood levels of PFCAs in ski wax technicians compared to a general population. The objective of this follow-up study was to determine concentrations of PFCAs, perfluorosulfonates (PFSAs), and fluorotelomer alcohols (FTOHs), precursor compounds that are known to degrade to PFCAs, in air collected in the breathing zone of ski wax technicians during work. We collected air samples by using ISOLUTE ENV+ cartridges connected to portable air pumps with an air flow of 2.0 L min(-1). PFCAs C5-C11 and PFSAs C4, C6, C8, and C10 were analyzed using LC-MS/MS and FTOHs 6:2, 8:2, and 10:2 with GC-MS/MS. The results show daily inhalation exposure of 8:2 FTOH in μg/m(3) air which is up to 800 times higher than levels of PFOA with individual levels ranging between 830-255000 ng/m(3) air. This suggests internal exposure of PFOA through biotransformation of 8:2 FTOH to PFOA and PFNA in humans.

Biotransformation of fluorotelomer compound to perfluorocarboxylates in humans

Levels of perfluorocarboxylates (PFCAs) in biological compartments have been known for some time but their transport routes and distribution patterns are not properly elucidated. The opinions diverge whether the exposure of the general population occurs indirect through precursors or direct via PFCAs. Previous results showed that ski wax technicians are exposed to levels up to 92 000 ng/m(3) of 8:2 fluorotelomer alcohol (FTOH) via air and have elevated blood levels of PFCAs. Blood samples were collected in 2007-2011 and analyzed for C(4)-C(18) PFCAs, 6:2, 8:2 and 10:2 unsaturated fluorotelomer acids (FTUCAs) and 3:3, 5:3 and 7:3 fluorotelomer acids (FTCAs) using UPLC-MS/MS. Perfluorooctanoic acid (PFOA) was detected in levels ranging from 1.90 to 628 ng/mL whole blood (wb). Metabolic intermediates 5:3 and 7:3 FTCA were detected in all samples at levels up to 6.1 and 3.9 ng/mL wb. 6:2, 8:2 and 10:2 FTUCAs showed maximum levels of 0.07, 0.64 and 0.11 ng/mL wb. Also, for the first time levels of PFHxDA and PFOcDA were detected in the human blood at mean concentrations up to 4.22 ng/mL wb and 4.25 ng/mL wb respectively. The aim of this study was to determine concentrations of PFCAs and FTOH metabolites in blood from ski wax technicians.

Testicular cancer and occupational exposure to polyvinyl chloride plastics: A case-control study

Exposure to polyvinyl chloride (PVC) plastics as a risk factor for testicular cancer was investigated. In total, 981 cases who were 20–75 years old and had reported to the Swedish Cancer Registry during 1993–1997 were included. One matched control from the population registry was used. Exposure was assessed by a questionnaire that was supplemented over the phone. Furthermore, an occupational hygienist qualified all exposures. In all, 791 matched pairs completed the questionnaire. Overall exposure to PVC plastics gave the odds ratio (OR)=1.35, 95% confidence interval (CI)=1.06–1.71, increasing with >10 year latency period to OR=1.45, 95% CI=1.06–1.98. No dose‐response relationships were found but rather an inverse relationship with the highest odds ratios in the lowest exposure category. In conclusion, no clear association with testicular cancer and exposure to PVC could be found in our study in contrast to a previous observation.

Exposure to Chemical Agents in Swedish Aluminum Foundries and Aluminum Remelting Plants?A Comprehensive Survey

Secondary aluminum melting is mainly performed in sand, die, and static die-casting foundries and remelting plants. In seven Swedish foundries and two remelting plants, the exposure and area concentrations of total dust, metals, organic gases, and vapors were determined mainly as daily, time-weighted averages (TWAs). For most combinations of jobs and agents, the exposure levels were well below the current threshold limits suggested by the American Conference of Governmental Industrial Hygienists (ACGIH). However, high exposure levels of mineral oil mist (geometric mean [GM] = 0.6 mg/m3) were observed in the die-casting process, with a maximum of 4 mg/m3. The findings were similar for total dust (GM = 5.1 mg/m3) and crystalline quartz (GM = 0.05 mg/m3) during molding operations in the sand foundries, maximum air concentrations being 31 mg/m3 and 0.22 mg/m3, respectively. Other agents which occasionally reached high exposure levels included furfuryl alcohol (up to 23 mg/m3 during furan binder use in sand foundries), aniline (up to 2.6 mg/m3 during thermal degradation of cold-box binders), and dimethylethylamine (up to 9 mg/m3) in the cold-box process used in static die-casting and sand foundries. The average aluminum exposure levels (GM = 0.043 mg/m3) were low in all foundries, individual values not exceeding 0.94 mg/m3. The exposures to metals were below 10 percent of their threshold limits. Similarly low levels were detected of polyaromatic hydrocarbons, phenol, formaldehyde, methylenebisphenyl diisocyanate, and phenylisocyanate. In the aluminum remelting plants, a few high exposure levels of total dust (GM = 1.4 mg/m3) up to 8 mg/m3 were detected in furnace workers. Aluminum and other metals were well below 10 percent of their threshold limits, with the exception of a few high concentrations of manganese, up to 0.14 mg/m3. The between-worker variability (GSDB) in the foundries for total dust, aluminum, and oil mist were on the order of 3-4. The heterogenicity of secondary aluminum melting requires assessment of a wide variety of chemical agents. For certain exposures, technical and medical monitoring programs are still needed.

Lung function and respiratory symptoms in hard metal workers exposed to cobalt.

Objective: To follow-up lung function and airway symptoms in workers exposed to cobalt dust at a hard metal plant. Methods: A total of 582 employees underwent spirometry and completed a questionnaire. A historical exposure matrix was created, assigning figures for historical and recent work-related exposure. Results: At the time of employment, 5% reported symptoms from respiratory tract. At follow-up, 5% suffered from persistent coughing and 7% reported asthma; 20% were daily smokers. Among nonsmokers without asthma, an evident, statistically nonsignificant, dose–response effect was seen between increasing cobalt exposure and decline in FEV1 (forced expiratory volume in the first second). In all exposure categories, the FEV1 in smokers declined 10 mL more per year than for nonsmokers. Conclusions: Even low levels of cobalt exposure seem to hamper lung function both in smokers and nonsmokers. This impact is considered low in relation to the effect of aging.

Quartz and Dust Exposure in Swedish Iron Foundries

Exposure to respirable quartz continues to be a major concern in the Swedish iron foundry industry. Recommendations for reducing the European occupational exposure limit (EU-OEL) to 0.05 mg/m 3 and the corresponding ACGIH® threshold limit value (ACGIH-TLV) to 0.025 mg/m 3 prompted this exposure survey. Occupational exposure to respirable dust and respirable quartz were determined in 11 Swedish iron foundries, representing different sizes of industrial operation and different manufacturing techniques. In total, 436 respirable dust and 435 respirable quartz exposure measurements associated with all job titles were carried out and are presented as time-weighted averages. Our sampling strategy enabled us to evaluate the use of respirators in certain jobs, thus determining actual exposure. In addition, measurements using real-time dust monitors were made for high exposure jobs. For respirable quartz, 23% of all the measurements exceeded the EU-OEL, and 56% exceeded the ACGIH-TLV. The overall geometric mean (GM) for the quartz levels was 0.028 mg/m 3 , ranging from 0.003 to 2.1 mg/m 3 . Fettler and furnace and ladle repair operatives were exposed to the highest levels of both respirable dust (GM = 0.69 and 1.2 mg/m 3 ; range 0.076–31 and 0.25–9.3 mg/m 3 and respirable quartz (GM = 0.041 and 0.052 mg/m 3 ; range 0.004–2.1 and 0.0098–0.83 mg/m 3 . Fettlers often used respirators and their actual quartz exposure was lower (range 0.003–0.21 mg/m 3 , but in some cases it still exceeded the Swedish OEL (0.1 mg/m 3 . For furnace and ladle repair operatives, the actual quartz exposure did not exceed the OEL (range 0.003–0.08 mg/m 3 , but most respirators provided insufficient protection, i.e., factors less than 200. In summary, measurements in Swedish iron foundries revealed high exposures to respirable quartz, in particular for fettlers and furnace and ladle repair workers. The suggested EU-OEL and the ACGIH-TLV were exceeded in, respectively, 23% and 56% of all measurements regardless of the type of foundry. Further work on elimination techniques to reduce quartz concentrations, along with control of personal protection equipment, is essential.

Inflammatory markers and exposure to occupational air pollutants

Objectives: To study the possible relationship between inhalation of airborne particles in the work environment and inflammatory markers in blood. Methods: Total dust was sampled in the breathing zone of 73 subjects working with welding, cutting, grinding and in foundries such as iron, aluminium, and concrete. Stationary measurements were used to study different size fractions of particles including respirable dust, particulate matter (PM)10 and PM2.5, the particle number concentration, the number of particles deposited in the alveoli, and total particle surface area concentration. Inflammatory markers such as interleukin-6 (IL-6), C-reactive protein (CRP), fibrinogen, d-dimer, and urate were measured in plasma or serum before the first shift after the summer vacation and after the first, second, and fourth shift. Results: The mean level of total dust in the breathing zone was 0.93 mg/m3. The proxies for mean respirable dust fraction was 0.27 mg/m3, PM10 0.60 mg/m3, and PM2.5 was 0.31 mg/m3. The IL-6 values increased by 50% after the first day, but decreased after shift on the second and fourth day. CRP did not increase after the first shift but increased by 17% after the second shift. Other biomarkers were unaffected. A multiple linear regression analysis of a subgroup of 47 subjects showed a statistically significant positive relationship between particle exposure and post-shift IL-6. Conclusion: This study supports previous investigations observing increases of IL-6 at air concentrations of PM10 or PM2.5 between 0.13 and 0.3 mg/m3 among healthy subjects. This increase of IL-6 may indicate an increased risk of coronary heart disease.

Epidemiological Adaptation of Quartz Exposure Modeling in Swedish Aluminum Foundries: Nested Case-Control Study on Lung Cancer

In a recent cohort study in aluminum foundries and remelting plants an unexpectedly high risk of lung cancer was found in workers in sand foundries. On the basis of present and historical measurement data, we developed a statistical model for exposure to total dust and crystalline quartz for different jobs and time periods. Cumulative dose estimates of total dust and crystalline quartz were calculated and used in a nested case-control study in the cohort. From the cohort of foundry workers (n = 5016), 46 cases of lung cancer were identified. The final analysis was performed on 31 cases and 233 controls with one year or more of employment. Historical measurement data from the 1960s and onward were collected, totaling 203 total dust and 103 crystalline quartz exposure observations. Regression models, using the determinants of job title, time period, type of foundry, and size of production, were developed for assessing historical total dust and crystalline quartz air concentrations. These estimates were used to calculate individual cumulative exposure in the case-control study. In the multiple linear regression analysis, the determinants explained much of the variations in dust level (r(2) = 0.58). The explained variation in crystalline quartz was much lower (r(2) = 0.13). The regression coefficients for the type of foundry, time period, and size of production were statistically significant for total dust. On the basis of the regression analysis, the final models were used to calculate individual cumulative exposures. The calculated cumulative dust and quartz exposures averaged 33 mg/m(3) * year and 0.42 mg/m(3) * year, respectively. The odds ratios (ORs) were not significant, but showed dose-response trends for both dust and crystalline quartz.