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Chamba PS, Baatjies R, Singh TS, Cumbane AJ, Jeebhay MF. Exposure Characterization of Wood Dust Particulate, Endotoxins, and (1-3)-β-d-Glucans, and Their Determinants in Mozambiquan Wood Processing Workers. Ann Work Expo Health 2023; 67:485-495. [PMID: 36715220 PMCID: PMC10119701 DOI: 10.1093/annweh/wxac100] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2022] [Accepted: 12/26/2022] [Indexed: 01/31/2023] Open
Abstract
OBJECTIVES Dust generated from wood processing comprises a heterogeneous mixture of inorganic and organic particles, including wood fragments, microorganisms, endotoxins, (1-3)-β-d-glucans, and allergens. This study characterized exposure to wood dust and its determinants in the Mozambiquan wood processing industry. METHODS A total of 124 personal inhalable samples, collected from a stratified random sample of 30 workers, were analysed for dust particulate, endotoxins, and (1-3)-β-d-glucans. Mixed-effects models were developed to investigate significant exposure determinants. RESULTS The geometric mean (GM) inhalable dust particulate concentrations were 3.29 mg m-3, 98 endotoxin units (EU) m-3, and 123 ng m-3 for (1-3)-β-d-glucans. Significant predictors for higher particulate levels included machinery (GMR = 1.93), sawing (GMR = 2.80), carpentry (GMR = 2.77), or painting (GMR = 3.03) tasks. Lebombo-ironwood species was associated with higher dust particulate levels (GMR = 1.97). Determinants of endotoxin concentrations included working with dry wood and damp cleaning methods, which were associated with lower levels. Working in closed buildings (GMR = 3.10) and dry sweeping methods were associated with higher (1-3)-β-d-glucan concentrations (GMR = 1.99). CONCLUSIONS Work tasks in certain exposure groups (machinery, sawing, carpentry, painting), processing certain wood species (Lebombo-ironwood) and working in closed buildings were associated with higher exposures, whilst using dry wood and damp cleaning practices reduced exposure levels.
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Affiliation(s)
- Paulino S Chamba
- Division of Occupational Medicine and Centre for Environmental & Occupational Health Research, School of Public Health, University of Cape Town, Cape Town, South Africa
- Department of Community Health, Faculty of Medicine, Eduardo Mondlane University, Maputo, Mozambique
| | - Roslynn Baatjies
- Division of Occupational Medicine and Centre for Environmental & Occupational Health Research, School of Public Health, University of Cape Town, Cape Town, South Africa
- Department of Environmental and Occupational Studies, Faculty of Applied Sciences, Cape Peninsula University of Technology, Cape Town, South Africa
| | - Tanusha S Singh
- National Institute for Occupational Health, National Health Laboratory Services, Johannesburg, South Africa
- Department of Environmental Health, School of Health Sciences, University of Johannesburg, Johannesburg, South Africa
- Department of Clinical Microbiology and Infectious Diseases, School of Pathology, University of the Witwatersrand, Johannesburg, South Africa
| | - Antonio J Cumbane
- Department of Chemical Engineering, Faculty of Engineering, Eduardo Mondlane University, Maputo, Mozambique
| | - Mohamed F Jeebhay
- Division of Occupational Medicine and Centre for Environmental & Occupational Health Research, School of Public Health, University of Cape Town, Cape Town, South Africa
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Górny RL, Gołofit-Szymczak M, Cyprowski M, Stobnicka-Kupiec A. Nasal lavage as analytical tool in assessment of exposure to particulate and microbial aerosols in wood pellet production facilities. THE SCIENCE OF THE TOTAL ENVIRONMENT 2019; 697:134018. [PMID: 31479905 DOI: 10.1016/j.scitotenv.2019.134018] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/09/2019] [Revised: 08/13/2019] [Accepted: 08/19/2019] [Indexed: 06/10/2023]
Abstract
Occupational exposure to wood dust and bioaerosols may lead to numerous respiratory tract diseases. We aimed to assess a degree of workplace contamination with dust, bacteria, fungi, endotoxins, and (1 → 3)-β-D-glucans released into the air during wood processing in pellet production facilities and to check against this background the usefulness of nasal lavage (NAL) as analytical tool for assessment of combined workers' exposure to airborne dust and microbiological contaminants. In 10 pellet plants, the particulate (wood dust) aerosol concentrations were determined by using Grimm aerosol spectrometer and CIS filter sampler. The collected CIS samples were subsequently used to evaluate endotoxin and (1 → 3)-β-D-glucan concentrations. Simultaneously with particulate aerosol, bioaerosol samples were collected by using 6-stage Andersen and single-stage MAS impactors. Bacterial and fungal aerosol concentrations were calculated and all isolated microorganisms were taxonomically identified. NAL fluid samples were collected from workers exposed to studied aerosols and the concentrations of proinflammatory mediators (IL-1β, IL-6, IL-8, and TNFα) and cytological image of nasal mucosa (expressed as cell counts) were established. The dynamics of production activities resulted in wide range of observed wood dust, microorganism, endotoxin and (1 → 3)-β-D-glucan concentrations reaching periodically extremely high values up to 65 mg m-3, 19,320 CFU m-3, 215 ng m-3 and 1525 ng m-3, respectively. Environmental stress caused by exposure to particulate and microbial aerosols stimulated immune response among workers of pellet production facilities. Correlation analysis revealed that interleukin levels and the number of cells in NAL were significantly affected by both wood dust and bioaerosol concentrations. As nasal mucosa serves as the primary barrier against inhaled pollutants, NAL seems a reliable analytical material to assess work-related adverse respiratory health outcomes derived from such exposure.
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Affiliation(s)
- Rafał L Górny
- Laboratory of Biohazards, Department of Chemical, Aerosol and Biological Hazards, Central Institute for Labour Protection - National Research Institute, Warsaw, Poland.
| | - Małgorzata Gołofit-Szymczak
- Laboratory of Biohazards, Department of Chemical, Aerosol and Biological Hazards, Central Institute for Labour Protection - National Research Institute, Warsaw, Poland
| | - Marcin Cyprowski
- Laboratory of Biohazards, Department of Chemical, Aerosol and Biological Hazards, Central Institute for Labour Protection - National Research Institute, Warsaw, Poland
| | - Agata Stobnicka-Kupiec
- Laboratory of Biohazards, Department of Chemical, Aerosol and Biological Hazards, Central Institute for Labour Protection - National Research Institute, Warsaw, Poland
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Stacey P, Simpson A, Hambling S. The Measurement of Wood in Construction Dust Samples: A Furnace Based Thermal Gravimetric Approach. Ann Work Expo Health 2019; 63:1070-1080. [PMID: 31550344 DOI: 10.1093/annweh/wxz072] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2019] [Revised: 08/01/2019] [Accepted: 08/28/2019] [Indexed: 11/14/2022] Open
Abstract
A furnace-based thermal gravimetric method was developed to measure wood in inhalable construction dust. The application of this method showed that reliance on the inhalable concentrations alone may substantially overestimate carpenters' exposures to wood dust at construction worksites. Test samples were prepared by collecting aerosols of gypsum, calcite, quartz, concrete, and wood dust onto quartz fibre filters using the Button inhalable sampler. The average difference between the measured and loaded mass of wood is 2% over the whole analytical range. Ninety percent of thermogravimetric measurements on all test samples (n = 35) were 13% or less. The limit of detection was measured as 0.065 mg. The thermal gravimetric method was applied to samples collected from four new build construction sites and one shop fitting worksite. The workplace inhalable wood dust results ranged from 15% to 104% of the total inhalable dust values. In addition, an x-ray diffraction (XRD) Rietveld method was applied as a complimentary approach to explain the composition of the remaining inhalable dust. Most combined thermal gravimetric and XRD measurements were within 10% of the total inhalable dust mass values, determined gravimetrically. Ninety-five percent were within 26%. The median proportion of mineral dust containing gypsum, calcite, quartz, dolomite, or rutile was 30%. The proportion of mineral dust on individual filters varied considerably.
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Affiliation(s)
- Peter Stacey
- The Health and Safety Executive, Harpur Hill, Buxton, UK
| | - Andrew Simpson
- The Health and Safety Executive, Harpur Hill, Buxton, UK
| | - Susan Hambling
- The Health and Safety Executive, Redgrave Court, Bootle, Merseyside, UK
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The Proof-of-the-Concept of Application of Pelletization for Mitigation of Volatile Organic Compounds Emissions from Carbonized Refuse-Derived Fuel. MATERIALS 2019; 12:ma12101692. [PMID: 31137692 PMCID: PMC6566988 DOI: 10.3390/ma12101692] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/12/2019] [Revised: 05/18/2019] [Accepted: 05/21/2019] [Indexed: 11/17/2022]
Abstract
Waste can be effectively reused through the production of carbonized refuse-derived fuel (CRDF) that enables further energy recovery. Developing cleaner production of CRDF requires consideration of practical issues of storage and handling. Thus, it needs to be ensured that CRDF does not pose an excessive risk to humans and the ecosystem. Very few studies indicate a wide variety of volatile organic compounds (VOCs) are present in CRDF, some of which are toxic. During handling, storage, transportation, and use of VOC-rich CRDF, workers and end-users could be exposed to emissions that could pose a health and safety hazard. Our recent study shows that CRDF densification via pelletization can increase the efficiency of storage and transportation. Thus, the following research question was identified: can pelletization mitigate VOCs emissions from CRDF during storage? Preliminary research aiming at the determination of the influence of CRDF pelletization on VOCs emission during storage was completed to address this question. The VOCs emissions from two types of CRDF: ground (loose, torrefied refuse-derived fuel (RDF)) and pelletized, were measured. Pelletization reduced the VOCs emissions potential during the four-day storage by ~86%, in comparison with ground CRDF. Mitigation of VOCs emissions from densified CRDF is feasible, and research is warranted to understand the influence of structural modification on VOCs emission kinetics, and possibilities of scaling up this solution into the practice of cleaner storage and transportation of CRDF.
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Rahman MA, Rossner A, Hopke PK. Carbon Monoxide Off-Gassing From Bags of Wood Pellets. Ann Work Expo Health 2018; 62:248-252. [PMID: 29293887 PMCID: PMC6788582 DOI: 10.1093/annweh/wxx104] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2017] [Revised: 10/25/2017] [Accepted: 11/30/2017] [Indexed: 11/16/2022] Open
Abstract
Wood pellets are increasingly used for space heating in the United States and globally. Prior work has shown that stored bulk wood pellets produce sufficient carbon monoxide (CO) to represent a health concern and exceed regulatory standards for occupational exposures. However, most of the pellets used for residential heating are sold in 40-pound (18.1 kg) plastic bags. This study measured CO emission factors from fresh, bagged-wood pellets as a function of temperature and relative humidity. CO concentrations increased with increasing temperature and moisture in the container. CO measurements in a pellet mill warehouse with stored pallets of bagged pellets had 8-h average CO concentrations up to 100 ppm exceeding occupational standards for worker exposure. Thus, manufacturers, distributors, and home owners should be aware of the potential for CO in storage areas and design facilities with appropriate ventilation and CO sensors.
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Affiliation(s)
| | - Alan Rossner
- Center for Air Resources Engineering and Science, Clarkson University, Potsdam, NY, USA
- Institute for a Sustainable Environment, Clarkson University, Potsdam, NY, USA
| | - Philip K Hopke
- Center for Air Resources Engineering and Science, Clarkson University, Potsdam, NY, USA
- Institute for a Sustainable Environment, Clarkson University, Potsdam, NY, USA
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Eriksson K, Bryngelsson IL, Hagström K. Temporal Trend in Wood Dust Exposure During the Production of Wood Pellets. Ann Work Expo Health 2017; 61:429-439. [PMID: 28355460 DOI: 10.1093/annweh/wxx019] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2016] [Accepted: 02/16/2017] [Indexed: 11/13/2022] Open
Abstract
Objective Wood dust data collected in the production of wood pellets during 2001 to 2013 were evaluated to study a temporal trend in inhalation exposure. Methods A linear mixed effects model of natural ln-transformed data was used to express the relative annual difference in inhalation wood dust exposure. Results There was an annual decrease of -20.5% of the geometric mean wood dust exposure during 2001 until 2013. The results were based on 617 inhalable dust samples collected at 14 different production units. The exposure to wood dust at the industrial premises investigated has decreased from a relatively high level of 6.4 mg m-3 in 2001 to 1.0 mg-3 in 2013. The Swedish Occupational Exposure Limit (SOEL) of 2 mg m-3 may still be exceeded. Conclusion Analysis of the temporal trend in soft wood production units revealed declines in exposure of 20.5% per annum. It is important that precautions are taken to protect workers from a hazardous exposure to wood dust at the premises as the SOEL of 2 mg m-3 at some occasions is still exceeded. Additional measurements of wood dust exposure should be carried out on a regular basis in wood pellet production units in Sweden as well in other countries.
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Affiliation(s)
- Kåre Eriksson
- Department of Occupational and Environmental Medicine, Umeå University, Umeå SE90187, Sweden
| | - Ing-Liss Bryngelsson
- Department of Occupational and Environmental Medicine, Örebro University Hospital, Örebro SE70185, Sweden
| | - Katja Hagström
- Department of Occupational and Environmental Medicine, Örebro University Hospital, Örebro SE70185, Sweden
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Löfstedt H, Hagström K, Bryngelsson IL, Holmström M, Rask-Andersen A. Respiratory symptoms and lung function in relation to wood dust and monoterpene exposure in the wood pellet industry. Ups J Med Sci 2017; 122:78-84. [PMID: 28276782 PMCID: PMC5441376 DOI: 10.1080/03009734.2017.1285836] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/11/2016] [Revised: 01/13/2017] [Accepted: 01/16/2017] [Indexed: 11/07/2022] Open
Abstract
INTRODUCTION Wood pellets are used as a source of renewable energy for heating purposes. Common exposures are wood dust and monoterpenes, which are known to be hazardous for the airways. The purpose of this study was to study the effect of occupational exposure on respiratory health in wood pellet workers. MATERIALS AND METHODS Thirty-nine men working with wood pellet production at six plants were investigated with a questionnaire, medical examination, allergy screening, spirometry, and nasal peak expiratory flow (nasal PEF). Exposure to wood dust and monoterpenes was measured. RESULTS The wood pellet workers reported a higher frequency of nasal symptoms, dry cough, and asthma medication compared to controls from the general population. There were no differences in nasal PEF between work and leisure time. A lower lung function than expected (vital capacity [VC], 95%; forced vital capacity in 1 second [FEV1], 96% of predicted) was noted, but no changes were noted during shifts. There was no correlation between lung function and years working in pellet production. Personal measurements of wood dust at work showed high concentrations (0.16-19 mg/m3), and exposure peaks when performing certain work tasks. Levels of monoterpenes were low (0.64-28 mg/m3). There was no association between exposure and acute lung function effects. CONCLUSIONS In this study of wood pellet workers, high levels of wood dust were observed, and that may have influenced the airways negatively as the study group reported upper airway symptoms and dry cough more frequently than expected. The wood pellet workers had both a lower VC and FEV1 than expected. No cross-shift changes were found.
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Affiliation(s)
- Håkan Löfstedt
- Department of Occupational and Environmental Medicine, Faculty of Medicine and Health Örebro University, Örebro, Sweden
| | - Katja Hagström
- Department of Occupational and Environmental Medicine, Faculty of Medicine and Health Örebro University, Örebro, Sweden
| | - Ing-Liss Bryngelsson
- Department of Occupational and Environmental Medicine, Faculty of Medicine and Health Örebro University, Örebro, Sweden
| | - Mats Holmström
- Division of Ear, Nose and Throat Diseases, Department of Clinical Science, Intervention and Technology, Karolinska Institutet, Stockholm, Sweden
| | - Anna Rask-Andersen
- Department of Medical Sciences, Occupational and Environmental Medicine, Uppsala University, Uppsala, Sweden
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Rahman MA, Rossner A, Hopke PK. Occupational exposure of aldehydes resulting from the storage of wood pellets. JOURNAL OF OCCUPATIONAL AND ENVIRONMENTAL HYGIENE 2017; 14:417-426. [PMID: 28475439 DOI: 10.1080/15459624.2017.1285491] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
An exposure assessment was conducted to investigate the potential for harmful concentrations of airborne short chain aldehydes emitted from recently stored wood pellets. Wood pellets can emit a number of airborne aldehydes include acetaldehyde, formaldehyde, propionaldehyde, butyraldehyde, valeraldehyde, and hexanal. Exposure limits have been set for these compounds since they can result in significant irritation of the upper respiratory system at elevated concentrations. Formaldehyde is a recognized human carcinogen and acetaldehyde is an animal carcinogen. Thus, air sampling was performed in a wood pellet warehouse at a pellet mill, two residential homes with bulk wood pellet storage bins, and in controlled laboratory experiments to evaluate the risk to occupants. Using NIOSH method 2539, sampling was conducted in five locations in the warehouse from April-June 2016 when it contained varying quantities of bagged pellets as well as two homes with ten ton bulk storage bins. The aldehyde concentrations were found to increase with the amount of stored pellets. Airborne concentrations of formaldehyde were as high as 0.45 ppm in the warehouse exceeding the NIOSH REL-C, and ACGIH TLV-C occupational exposure limits (OELs). The concentrations of aldehydes measured in the residential bins were also elevated indicating emissions may raise indoor air quality concerns for occupants. While individual exposures are of concern the combined irritant effect of all the aldehydes is a further raise the concerns for building occupants. To minimize exposure and the risk of adverse health effects to a building's occupants in storage areas with large quantities of pellets, adequate ventilation must be designed into storage areas.
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Affiliation(s)
- Mohammad Arifur Rahman
- a Center for Air Resources Engineering and Science , Clarkson University , Potsdam , New York
| | - Alan Rossner
- a Center for Air Resources Engineering and Science , Clarkson University , Potsdam , New York
- b Institute for the Sustainable Environment , Clarkson University , Potsdam , New York
| | - Philip K Hopke
- a Center for Air Resources Engineering and Science , Clarkson University , Potsdam , New York
- b Institute for the Sustainable Environment , Clarkson University , Potsdam , New York
- c Department of Public Health Sciences , University of Rochester School of Medicine and Dentistry , Rochester , New York
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Rohr AC, Campleman SL, Long CM, Peterson MK, Weatherstone S, Quick W, Lewis A. Potential Occupational Exposures and Health Risks Associated with Biomass-Based Power Generation. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2015; 12:8542-605. [PMID: 26206568 PMCID: PMC4515735 DOI: 10.3390/ijerph120708542] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/01/2015] [Revised: 07/03/2015] [Accepted: 07/14/2015] [Indexed: 12/19/2022]
Abstract
Biomass is increasingly being used for power generation; however, assessment of potential occupational health and safety (OH&S) concerns related to usage of biomass fuels in combustion-based generation remains limited. We reviewed the available literature on known and potential OH&S issues associated with biomass-based fuel usage for electricity generation at the utility scale. We considered three potential exposure scenarios--pre-combustion exposure to material associated with the fuel, exposure to combustion products, and post-combustion exposure to ash and residues. Testing of dust, fungal and bacterial levels at two power stations was also undertaken. Results indicated that dust concentrations within biomass plants can be extremely variable, with peak levels in some areas exceeding occupational exposure limits for wood dust and general inhalable dust. Fungal spore types, identified as common environmental species, were higher than in outdoor air. Our review suggests that pre-combustion risks, including bioaerosols and biogenic organics, should be considered further. Combustion and post-combustion risks appear similar to current fossil-based combustion. In light of limited available information, additional studies at power plants utilizing a variety of technologies and biomass fuels are recommended.
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Affiliation(s)
- Annette C Rohr
- Electric Power Research Institute, Palo Alto, CA 94304, USA.
| | | | | | | | - Susan Weatherstone
- ON Technologies (Ratcliffe) Ltd., Ratcliffe on Soar, Nottinghamshire, NG11 0EE, UK.
| | - Will Quick
- ON Technologies (Ratcliffe) Ltd., Ratcliffe on Soar, Nottinghamshire, NG11 0EE, UK.
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Hagstrom K, Jacobsen G, Sigsgaard T, Schaumburg I, Erlandsen M, Schlunssen V. Predictors of Monoterpene Exposure in the Danish Furniture Industry. ANNALS OF OCCUPATIONAL HYGIENE 2011; 56:253-63. [DOI: 10.1093/annhyg/mer091] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
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Lee T, Harper M, Slaven JE, Lee K, Rando RJ, Maples EH. Wood dust sampling: field evaluation of personal samplers when large particles are present. THE ANNALS OF OCCUPATIONAL HYGIENE 2011; 55:180-91. [PMID: 21036895 PMCID: PMC3037778 DOI: 10.1093/annhyg/meq075] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/01/2010] [Accepted: 08/30/2010] [Indexed: 11/29/2022]
Abstract
Recent recommendations for wood dust sampling include sampling according to the inhalable convention of International Organization for Standardization (ISO) 7708 (1995) Air quality--particle size fraction definitions for health-related sampling. However, a specific sampling device is not mandated, and while several samplers have laboratory performance approaching theoretical for an 'inhalable' sampler, the best choice of sampler for wood dust is not clear. A side-by-side field study was considered the most practical test of samplers as laboratory performance tests consider overall performance based on a wider range of particle sizes than are commonly encountered in the wood products industry. Seven companies in the wood products industry of the Southeast USA (MS, KY, AL, and WV) participated in this study. The products included hardwood flooring, engineered hardwood flooring, door skins, shutter blinds, kitchen cabinets, plywood, and veneer. The samplers selected were 37-mm closed-face cassette with ACCU-CAP™, Button, CIP10-I, GSP, and Institute of Occupational Medicine. Approximately 30 of each possible pairwise combination of samplers were collected as personal sample sets. Paired samplers of the same type were used to calculate environmental variance that was then used to determine the number of pairs of samples necessary to detect any difference at a specified level of confidence. Total valid sample number was 888 (444 valid pairs). The mass concentration of wood dust ranged from 0.02 to 195 mg m(-3). Geometric mean (geometric standard deviation) and arithmetic mean (standard deviation) of wood dust were 0.98 mg m(-3) (3.06) and 2.12 mg m(-3) (7.74), respectively. One percent of the samples exceeded 15 mg m(-3), 6% exceeded 5 mg m(-3), and 48% exceeded 1 mg m(-3). The number of collected pairs is generally appropriate to detect a 35% difference when outliers (negative mass loadings) are removed. Statistical evaluation of the nonsimilar sampler pair results produced a finding of no significant difference between any pairing of sampler type. A practical consideration for sampling in the USA is that the ACCU-CAP™ is similar to the sampler currently used by the Occupational Safety and Health Administration for purposes of demonstrating compliance with its permissible exposure limit for wood dust, which is the same as for Particles Not Otherwise Regulated, also known as inert dust or nuisance dust (Method PV2121).
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Affiliation(s)
- Taekhee Lee
- Exposure Assessment Branch, Health Effects Laboratory Division, National Institute for Occupational Safety and Health, Centers for Disease Control and Prevention, Morgantown, WV 26505, USA.
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12
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Feveile H, Schmidt L, Hannerz H, Hougaard KS. Industrial differences in female fertility treatment rates--a new approach to assess differences related to occupation? Scand J Public Health 2011; 39:164-71. [PMID: 21239478 DOI: 10.1177/1403494810391525] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
AIMS Infertility is highly prevalent and 16-26% of women trying to achieve a pregnancy experience infertility in one or more periods. Several exposures in the work environment have been hypothesized to affect female reproduction. This study aimed to estimate relative rates (RR) of female fertility treatment in the 57 industrial groups in Denmark. METHODS The closed cohort of all 20-39 year old economically active women in Denmark by January 2001 (n = 567,816) were followed-up for hospital contacts due to infertility from 2001 to 2005 as registered in the Danish Occupational Hospital Register. Age-standardized relative rates for being diagnosed as infertile were estimated by industry. Further standardization with respect to socioeconomic status was also performed. RESULTS In total, 12,575 women were diagnosed with infertility during the follow-up period. Three industries presented with statistically significant elevations in age-standardized RRs: hospitals (RR = 1.27, 95% confidence interval (CI): 1.20-1.35), general and dental practice (RR = 1.17, 95% CI: 1.02-1.35) and other health care (RR = 1.24, 95% CI: 1.09-1.41). Standardization for socioeconomic status rendered two industries that were statistically significantly elevated: manufacture of wood and wood products (RR = 1.20, 95% CI: 1.02-1.42) and hospitals (RR = 1.17, 95% CI: 1.10-1.24). CONCLUSIONS Interpretation of the results is complex, since the relative contributions to the observed inequalities of the work environment and, for example, differences in inclination to start a family or in proneness to seek treatment are difficult to resolve. Withstanding shortcomings and limitations, register data of fertility treatment offers a possibility to suggest industries for further investigation of reproductive health.
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Affiliation(s)
- Helene Feveile
- National Research Centre for the Working Environment, Copenhagen, Denmark
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Axelsson S, Eriksson K, Nilsson U. Determination of resin acids during production of wood pellets—a comparison of HPLC/ESI-MS with the GC/FID MDHS 83/2 method. ACTA ACUST UNITED AC 2011; 13:2940-5. [DOI: 10.1039/c0em00543f] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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Granström KM. Underestimation of terpene exposure in the Nordic wood industry. JOURNAL OF OCCUPATIONAL AND ENVIRONMENTAL HYGIENE 2010; 7:144-151. [PMID: 20029714 DOI: 10.1080/15459620903476330] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
This study determined that emission of sesquiterpenes from processed wood warrants attention in the work environment. Currently, only the monoterpenes in the terpene group are monitored in occupational hygiene studies. Terpene emissions are a work environment issue for industries that process wood, as they are known to cause respiratory difficulties and mucous membrane irritation. Fresh sawdust of the most common boreal conifers, Norway spruce (Picea abies) and Scots pine (Pinus sylvestris), was subjected to processing (drying), and the emissions were analyzed with a gas chromatograph-mass spectrometer. The data indicate that workers are exposed to significant amounts of sesquiterpenes, an observation that has not been recorded previously at wood processing plants. On average, the proportion of sesquiterpenes to monoterpenes was 21 +/- 5% (STD, n = 11) for spruce and 15 +/- 5% (STD, n = 13) for pine. The composition of terpenes emitted in air from spruce wood differs from the composition in resin. The sum of monoterpenes and sesquiterpenes can exceed the occupational exposure limit for turpentine for processes where monoterpene concentrations are already close to the occupational exposure limit, and for processes involving the processing of bark. Findings suggest that future studies of health effects from terpenes in air should measure monoterpenes and sesquiterpenes to assess whether the current OELs are appropriate.
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Affiliation(s)
- Karin M Granström
- Department of Energy, Environmental and Building Technology, Karlstad University, Karlstad, Sweden.
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Hagström K, Lundholm C, Eriksson K, Liljelind I. Variability and determinants of wood dust and resin acid exposure during wood pellet production: measurement strategies and bias in assessing exposure-response relationships. ACTA ACUST UNITED AC 2008; 52:685-94. [PMID: 18703543 DOI: 10.1093/annhyg/men052] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
Abstract
Production of wood pellets is a relatively new and expanding industry in which the exposure profiles differ from those in other wood-processing industries like carpentries and sawmills where there are lower levels of wood dust. Sixty-eight personal exposure measurements of wood dust (inhalable and total dust) and resin acids were collected for 44 participants at four production plants located in Sweden. Results were used to estimate within- and between-worker variability and to identify uniformly exposed groups and determinants of exposure. In addition, overexposure, whether the risk of the long-term mean exposure of a randomly selected worker exceeding the occupational exposure limit is acceptably low, was calculated as well as the underestimation of the exposure-response relationship (attenuation). Greater variability in exposure between work shifts than between workers was observed with the within-worker variation accounting for 57-99% of the total variance in the individual-based model. Several uniformly exposed groups were detected but were mostly associated with a between-worker variation of zero which is an underestimation of the between-worker variation but an indication of uniformly exposed groups. Cleaning was identified as a work task that increases exposure slightly; so reducing workers' exposure during this operation is advisable. The levels of wood dust were high and were found to pose unacceptable risks of overexposure at all plants for inhalable dust and at three out of four plants for total dust. These findings show that exposure to dust needs to be reduced in this industry. For resin acids, the exposure was classed as acceptable at all plants. According to an individual-based model constructed from the data, the level of attenuation was high, and thus there would be substantial bias in derived dose-response relationships.
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Affiliation(s)
- Katja Hagström
- Department of Occupational and Environmental Medicine, Orebro University Hospital, 701 85 Orebro, Sweden.
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