bluuebunny/crossref_metadata_2025 huggingface dataset:
Management of occupational back pain: the Sherbrooke model. Results of a pilot and feasibility study.
Authors: Loisel P , Durand P , Abenhaim L , Gosselin L , Simard R , Turcotte J , Esdaile J M
Published: December 2008

OBJECTIVES--The aim was to combat occurrence of chronic occupational back pain. METHODS--A multidisciplinary model to manage back pain that includes both clinical and ergonomic approaches has been developed. Early detection, early clinical and ergonomic evaluations, and early active treatment make up the cornerstone of management. Detection of cases starts after four weeks of absence from work. An ergonomic intervention is implemented at six weeks. A medical specialist is involved at eight weeks. If return to work is not possible after 12 weeks, a functional recovery therapy followed by a therapeutic return to work is implemented. A multidisciplinary team decides if return to original or modified work is possible or if vocational rehabilitation is necessary. This model has been implemented by the investigators in the Sherbrooke (Quebec, Canada) area, and is presently being evaluated through a randomised trial in 31 industrial settlements (about 20,000 workers). A cluster randomisation of industries and workers will allow separate testing of ergonomic and clinical interventions. RESULTS--One year after implementation, 31 of 35 of the eligible industrial sites participated in the study and 79 of 88 of the eligible workers affected by recent back pain had agreed to participate. Ergonomic and clinical interventions have been implemented as planned. Only three workers dropped out. Hence this global clinical and ergonomic management programme has been shown to be feasible in a general population. CONCLUSION--A global management programme of back pain joining ergonomic and clinical intervention with a multidisciplinary approach has not been tested yet. Linking these two strategies in a same multidisciplinary team represents a systemic approach to this multifactorial ailment. During the first year of this trial we did not find any conflict between these two interventions from the employer's or worker's point of view.
Effect of variation of exposure to airborne chlorobenzene on internal exposure and concentrations of urinary metabolite.
Authors: Kumagai S , Matsunaga I
Published: December 2008

OBJECTIVES--This study aimed to develop a physiologically based pharmacokinetic model for chlorobenzene and to investigate the effect of variation in exposure to chlorobenzene on the chlorobenzene concentration in blood and the urinary concentration of 4-chlorocatechol. METHODS--A physiologically based pharmacokinetic model was developed and the simulated results of urinary 4-chlorocatechol concentrations were compared with the values found in experiments and field surveys. The area under the chlorobenzene concentration-time curve in blood (CBBauc) was selected as the measure of internal exposure related to the chronic effect of chlorobenzene. The maximum one-hour time weighted average value of chlorobenzene concentration in blood (CBBmax) was chosen as the measure of internal exposure related to the acute effect of chlorobenzene. The total amount of urinary 4-chlorocatechol (TOTCC) and that excreted during the last four hours (CC(4-8)) or two hours (CC(6-8)) of exposure as well as that excreted during two hours on the next morning (CC(22-24)) were used to represent concentrations of urinary metabolites. The effects of variation of the one-hour time weighted averages of airborne chlorobenzene exposure (CBAs) on the internal exposures and the concentrations of urinary metabolites were investigated with the pharmacokinetic model. RESULTS--The comparison of the simulated results with the observed data showed that the pharmacokinetic model can be used to estimate the urinary concentrations of 4-chlorocatechol. The CBBauc and TOTCC were not affected by changes in both the geometric SD (GSD) of CBAs or the variations in CBAs. The CBBmax varied with changes in both the GSD and CBAs. The CC(4-8) and CC(6-8) did not vary with the GSD, but these concentrations were affected by the change in the CBAs. Although there was little effect of the GSD and CBAs on the CC(22-24), this value highly reflected the exposure over the preceding days. CONCLUSION--To protect workers from the chronic effect of chlorobenzene, it may be sufficient to control the daily average exposure. To protect from the acute effect, however, the short term exposure must be controlled as well. The values of CC(4-8) and CC(6-8) were acceptable for estimating daily average exposure, but the CC(22-24) was not.
Occupational exposures estimated by means of job exposure matrices in relation to lung function in the PAARC survey.
Authors: Le Moual N , Orlowski E , Schenker M B , Avignon M , Brochard P , Kauffmann F
Published: December 2008

OBJECTIVES--The aim of this analysis of the French Cooperative PAARC (Pollution Atmosphérique et Affections Respiratoires Chroniques) survey, was to test whether occupational exposures to dusts, gases, or chemical fumes or to specific hazards, estimated by job exposure matrices, were related to a decrease in forced expiratory volume in one second (FEV1). METHODS--The most recent occupation was recorded in adults, aged 25-59, from non-manual worker households. Analysis was restricted to 10,046 subjects whose occupation was encountered at least 10 times in the study and who performed good FEV1 tracings. From occupational title, exposures to dusts, gases, and chemical fumes, and to specific hazards were classified in three categories (no, low, and high) with a British, a French, and an Italian job exposure matrix. Specific hazards were analysed for the British and French job exposure matrices for the same 42 specific dusts, gases, and chemical fumes. To limit spurious associations, a selection of seven hazard groups and 12 specific hazards was set before the start of the analysis. Based on the consistency of the relations according to sex and the British and French job exposure matrices, associations of age, height, city, and smoking adjusted FEV1 score with occupational exposures were classified as very likely, possible, or unlikely. RESULTS--For the three job exposure matrices and both sexes clear exposure-response relations between the level of exposure to dusts, gases, and chemical fumes, and a decrease in FEV1 were found. Associations with FEV1 were classified as very likely for known hazards such as organic dusts and textile dusts, and not previously recognised hazards such as polycyclic aromatic hydrocarbons (PAHs) and detergents, and as possible for solvents, waxes and polishes, and diesel fumes. Associations found for PAHs and solvents were confirmed by the Italian job exposure matrix. Associations remained significant in women, but not in men, after adjustment for educational level. CONCLUSIONS--Hypotheses have been generated for exposure to detergents, PAHs, and solvents, but they need to be interpreted with caution before replication. Significant associations found for known risk factors with a decrease in FEV1 are arguments for the validity of the matrices. Despite the expected limitations of job exposure matrices, these results encourage further work to improve exposure assessment by job exposure matrices.
The risk of acquiring Q fever on farms: a seroepidemiological study.
Authors: Thomas D R , Treweek L , Salmon R L , Kench S M , Coleman T J , Meadows D , Morgan-Capner P , Caul E O
Published: December 2008

OBJECTIVES--To determine the occupational risk of Q fever. DESIGN--Cohort study. SETTING--Community: five English local authority districts. SUBJECTS AND METHODS--Prevalence and incidence of immunoglobulin G (IgG) specific antibody to Coxiella burnetii phase II antigen was measured in a representative (study) cohort of farm workers in the United Kingdom, and detailed exposure data were collected. Also seroprevalence of Q fever in a (control) cohort of police and emergency service personnel was measured. RESULTS--Prevalence was significantly (P < 0.01) higher in the study cohort (105/385 v 43/395). During the first 12 month period after enrollment no seroconversions were found (upper 95% confidence limit: 1318/100,000/year). During the second 12 month period after enrollment two seroconversions were found, equalling an incidence of 813/100,000/year (95% confidence interval (95% CI) 98-2937/100,000/year). No association was found between seroprevalence and age. In the study cohort, extent of total contact with farm animals seemed more important than exposure to any specific animal: full time employees were more than four times more likely to be antibody positive than part time employees (P < 0.05). Exposure to cattle, but not sheep, goats, cats, raw milk, and hay (all reported sources of Q fever) was associated with being positive to Coxiella burnetii IgG by univariate analysis but this association was not independent of total farm animal contact. CONCLUSIONS--The risk of Q fever on livestock farms is related to contact with the farm environment rather than any specific animal exposure. The absence of an increasing prevalence with age suggests that exposure may occur as clusters in space and time (outbreaks).
Dose-response relation for vascular disorders induced by vibration in the fingers of forestry workers.
Authors: Bovenzi M , Franzinelli A , Mancini R , Cannavà M G , Maiorano M , Ceccarelli F
Published: December 2008

OBJECTIVES--To study the relation between the prevalence of vascular disorders (white finger) and vibration exposure in a group of 222 forestry workers, of whom 164 (73.9%) had work experience limited to antivibration (AV) chain saws only and 58 (26.1%) had operated both non-AV and AV chain saws. METHODS--The chain saw operators and 195 control workers never exposed to hand transmitted vibration were interviewed with health and workplace assessment questionnaires. The diagnosis of vibration induced white finger (VWF) was made on the basis of subjective symptoms of finger blanching and the results of a cold test with plethysmographic measurement of systolic blood pressure of the finger. Vibration was measured on a representative sample of AV and non-AV chain saws. Daily vibration exposure was assessed as eight hour energy equivalent frequency weighted acceleration (A(8)). A lifetime vibration dose was estimated for each of the forestry workers. RESULTS--The overall prevalence of VWF among the forestry workers was 23.4%. The diagnosis of VWF was made in 13.4% of the forestry workers who handled only AV chain saws and in 51.7% of those who had also operated non-AV chain saws in the past. Raynaud's phenomenon was found in 2.6% of the controls. In the forestry workers, the risk for VWF showed positive increments with each increment of vibration dose, suggesting a monotonic dose-response relation. The responsiveness to cold in the digital arteries of the forestry workers was also found to increase with increasing vibration dose and severity of VWF. The estimated relation between VWF and vibration exposure showed that the expected prevalence of VWF increased almost linearly to either A(8) (with exposure duration unchanged) or the number of years of exposure (with equivalent acceleration unchanged). CONCLUSIONS--In this study of VWF among forestry workers, the estimated dose-response relation showed that if the magnitude of vibration acceleration is doubled, the total duration of exposure should be halved to produce an equivalent effect. On the basis of the assessment of vibration exposure, the estimated risk for VWF in the study population was found to be lower than that predicted by the international standard ISO 5349. These findings suggest a revision of the risk estimates for VWF currently provided by ISO 5349.
Evaluation of biomarkers in plasma, blood, and urine samples from coke oven workers: significance of exposure to polycyclic aromatic hydrocarbons.
Authors: Ovrebø S , Haugen A , Farmer P B , Anderson D
Published: December 2008

OBJECTIVE--The aim was to assess the significance of two biomarkers; antibody to benzo(a)pyrene DNA adducts and concentration of hydroxyethylvaline haemoglobin adducts in samples from a well studied group of coke oven workers. As a measure of exposure we have used 1-hydroxypyrene in urine. METHODS--Urine and blood samples were collected from coke oven workers and a control group. Samples from coke oven plant workers were collected in January and June. 1-Hydroxypyrene was measured in urine by high performance liquid chromatography (HPLC), antibodies to benzo(a)pyrene DNA adducts were measured by ELISA and hydroxyethylvaline haemoglobin adducts were measured by gas chromatography-mass spectrometry (GC-MS). RESULTS--Mean urinary 1-hydroxypyrene in samples from coke oven workers varied from 1.11 to 5.53 umol/mol creatinine and 0.14 umol/mol creatinine in the control group. Workers at the top side had the highest values of urinary 1-hydroxypyrene. Antibody to benzo(a)pyrene DNA adducts did not correlate with either 1-hydroxypyrene nor length of work at the coke oven plant. But antibody concentration in samples collected in January was predictive of the concentration in samples collected in June. A small non-significant increase in hydroxyethylvaline haemoglobin adducts was found in samples from coke oven workers relative to the control group when comparing smokers and nonsmokers separately. CONCLUSION--1-Hydroxypyrene correlates well with exposure groups based on job description. Antibodies to benzo(a)-pyrene DNA adducts was related to people and not exposure. Work at a coke oven plant might lead to increased hydroxyethylvaline haemoglobin adducts.
Diabetes mellitus and arsenic exposure: a second look at case-control data from a Swedish copper smelter.
Authors: Rahman M , Axelson O
Published: December 2008

OBJECTIVES--To find out whether a newly found association between diabetes mellitus and arsenic in drinking water in Taiwan could be reproduced in copper smelters with arsenic exposure. METHODS--Extended analysis of a previous case-control study from 1978 was based on death records and objective exposure information from the company. The final analysis included only those employed at the smelter. Cases were 12 people with diabetes mellitus on the death certificate and those for whom there was clinical information on this disease. Controls were 31 people without cancer, cardiovascular and cerebrovascular disease as these disease categories had been associated with arsenic exposure in the original study and elsewhere. RESULTS--The odds ratios found for diabetes mellitus with increasing arsenic exposure categories were (reference level = 1), 2.0, 4.2, and 7.0, but the 95% confidence intervals included unity. Unstratified test for trend was weakly significant, P = 0.03. CONCLUSIONS--Although based on small numbers, the findings provide some support for the suggestion that arsenic exposure could sometimes play a part in the development of diabetes mellitus.
Occupational exposure to polychlorinated dibenzo-p-dioxins and dibenzofurans in a magnesium production plant.
Authors: Hansson M , Grimstad T , Rappe C
Published: December 2008

OBJECTIVES--The production of magnesium is a well known source of both aliphatic and aromatic chlorinated compounds, among others the polychlorinated dibenzo-p-dioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs). The aim of this study was to establish whether increased concentrations of PCDDs and PCDFs could be found in the blood of workers in a magnesium plant. METHODS--Blood plasma from 10 workers, employed at a magnesium plant for 10 to 36 years, and from a control group consisting of nine people who had no direct contact with the production were studied. Isomer specific analyses of PCDDs and PCDFs by means of high resolution gas chromatography/high resolution mass spectrometry (HRGC/HRMS) techniques were performed. RESULTS--A significant increase was found in the concentrations of some of the congeners, mainly PCDFs, in the workers compared with the control group. Octachlorodibenzofuran (OCDF) is the congener that most strongly correlates with occupational exposure in the magnesium plant. Low concentrations of 1,2,3,4,6,8,9-heptachlorodibenzofuran were found in seven of the workers. Such isomers--that is, not 2,3,7,8-substituted--are rarely found in human samples. CONCLUSION--Due to the long biological half lives and lipid solubility of PCDDs and PCDFs, blood analyses may serve as an index of past cumulative occupational exposure and a means of assessing a person's exposure situation.
Does occupational exposure to dust prevent colorectal cancer?
Authors: Finkelstein M M
Published: December 2008

OBJECTIVES--To explore the impression that occupational epidemiologists tend to focus on associations suggestive of increased risk and tend to ignore those associations in which risk is not increased. To examine the risk of colorectal cancer in cohorts exposed to dust, cohorts in which it has been suggested that occupational exposure is a cause of increased risk of stomach cancer. METHODS--A review of the publications in the English language on mortality among hard rock miners, granite, and quarry workers identified from a MEDLINE search and the index of the library of the Ontario Ministry of Labour. RESULTS--When all of the studies were combined, there were significant excesses of lung and stomach cancers, but a significant deficit of colorectal cancer (standardised mortality ratio (SMR) = 83.9; 95% confidence interval (95% CI) 76-91). Overall mortality from gastrointestinal cancer was close to expectation (SMR = 105; 95% CI 99-111). Among those cohorts with increased risk of stomach cancer, rates of colorectal cancer were significantly decreased (SMR = 80; 95% CI 72-88). Among cohorts without increased risk of stomach cancer, the SMR for colorectal cancer was not significantly different from 100 (SMR = 98; 95% CI 81-115). CONCLUSIONS--This review supports the impression that occupational epidemiologists tend to focus on associations suggestive of increased risk and tend to ignore those associations in which risk is not increased. The explanation for the inverse association between risk of stomach and colorectal cancer is uncertain and deserves further study.
Mortality of butchers and cooks identified from the 1961 census of England and Wales.
Authors: Coggon D , Wield G
Published: December 2008

OBJECTIVES--To explore a suspected hazard of lung cancer in butchers and cooks. METHODS--4018 male butchers and 2062 male cooks were identified from the 1961 census of England and Wales. 4857 (79.9%) of these men were traced through the National Health Service Central Register, and 3518 deaths were recorded during follow up to the end of 1992. Mortality from lung cancer and other causes was compared with that of the general population by the person-years method. RESULTS--Mortality from all causes was significantly below that of the national population in both butchers (standardized mortality ratio (SMR) 0.94, 95% confidence interval (95% CI) 0.90-0.98) and cooks (SMR 0.89, 95% CI 0.84-0.95). When allowance was made for a latency of 20 years from entry to follow up, the deficit in butchers was reduced, but that in cooks persisted, and was largely explained by a shortfall of deaths from cancer and circulatory disease. Mortality from lung cancer was close to expectation in the butchers (SMR 1.01, 95% CI 0.90-1.13) and below expectation in the cooks (SMR 0.93, 95% CI 0.75-1.13). Cooks had increased mortality from cancers of the oral cavity (SMR 5.57) and pharynx (SMR 2.66). CONCLUSIONS--The findings provide no support for an occupational hazard of lung cancer in either butchers or cooks. The possibility of excess risk in sub-groups of these occupations cannot be discounted. The high rates of oral and pharyngeal cancer in cooks are probably a consequence of high alcohol consumption.
Manual handling activities and risk of low back pain in nurses.
Authors: Smedley J , Egger P , Cooper C , Coggon D
Published: December 2008

OBJECTIVE--To investigate the risk factors for low back pain in hospital nurses, with particular emphasis on the role of specific nursing activities. METHODS--A cross sectional survey of 2405 nurses employed by a group of teaching hospitals was carried out. Self administered questionnaires were used to collect information about occupational activities, non-occupational risk factors for back symptoms, and history of low back pain. RESULTS--The overall response rate was 69%. Among 1616 women, the lifetime prevalence of back pain was 60% and the one year period prevalence 45%. 10% had been absent from work because of back pain for a cumulative period exceeding four weeks. Rates in men were generally similar to those in women. In women back pain during the previous 12 months was weakly associated with height, and was significantly more common in those who reported frequent non-musculoskeletal symptoms such as headache and low mood. After adjustment for height and non-musculoskeletal symptoms, significant associations were found with frequency of manually moving patients around on the bed, manually transferring patients between bed and chair, and manually lifting patients from the floor. In contrast, no clear increase in risk was found in relation to transfer of patients with canvas and poles, manually lifting patients in and out of the bath, or lifting patients with mechanical aids. Confirmation of these findings is now being sought in a prospective study of the same population. CONCLUSIONS--This study confirms that low back pain is highly prevalent among nurses and is associated with a high level of sickness absence. People who often report non-musculoskeletal symptoms were significantly more likely to report low back pain. Specific manual handling tasks were associated with an increased risk of back pain; however, no such association was found with mechanised patient transfers.
Respiratory health of workers exposed to metal dusts and foundry fumes in a copper refinery.
Authors: Ostiguy G , Vaillancourt C , Bégin R
Published: December 2008

OBJECTIVES--To assess airflow limitation in workers exposed long term to metal dust, the prevalence of pleural plaques in those workers exposed in the past to asbestos, the influence of pleural plaques on lung function, and the possible association with airway disease caused by asbestos. METHODS--A cross sectional and longitudinal (seven year) survey of 494 long term (mean (SEM) 21(1) years) workers in a copper refinery was carried out from medical questionnaires, chest radiographs, and forced spirometry. RESULTS--The prevalence of lifetime non-smokers was 19%, current smokers 39%, and ex-smokers 42%. The prevalence of chronic obstructive pulmonary diseases (COPD) (forced expiratory volume in one second (FEV1) < 80% predicted) was 5%, small airway dysfunction (SAD) (maximal mid-expiratory flow (MMEF) < 60% predicted) was 7%, and this did not differ from the control population. The COPD and SAD were associated with cumulative smoking index but not with the cumulative work years at the plant or with any type of work at the plant. The mean (SEM) reduction of FEV1 was 20(7) ml in non-smokers, 26(4) ml in smokers, and 26(5) ml in ex-smokers (P > 0.05). In the smokers and ex-smokers with COPD, the loss of FEV1 was 53(10) (P < 0.02). The prevalence of pleural plaques was 11% (P < 0.0001); pleural plaques were found in older workers with known exposure to asbestos. The pleural plaques were circumscribed and associated with a non-significant 196 ml reduction in forced vital capacity (FVC) and non-significant reduction of FVC over time. The pleural plaques were not associated with COPD or SAD. The cumulative smoking index obtained by a technician did not differ from that by a chest physician. CONCLUSIONS--Despite exposures to asbestos that produced pleural plaques and exposures to metal dusts and foundry fumes the long term workers of this plant did not have excessive prevalence of COPD or SAD. The data suggest that low level long term exposure to metal dusts, gases, and foundry fumes do not necessarily cause respiratory dysfunction, circumscribed pleural plaques with low grades of width and extent do not reduce FVC significantly, and exposure to asbestos dust that produced pleural plaques does not necessarily produce airway dysfunction.
Mortality and cancer morbidity in workers from an aluminium smelter with prebaked carbon anodes--Part I: Exposure assessment.
Authors: Rønneberg A
Published: December 2008

OBJECTIVES--To design a job-exposure matrix for epidemiological studies of men who had worked in a Norwegian aluminium smelter between 1922 and 1975. METHODS--Jobs held by cohort members were identified from personnel records. Tasks and their locations were determined for all jobs, and information was gathered about changes in exposure conditions over time. The jobs were combined into categories thought to have experienced similar exposure conditions, and time weighted average exposures were estimated on a relative scale. The results were reviewed by a panel of former smelter employees and an experienced industrial hygienist. RESULTS--96 different jobs could be identified from the cohort members' work histories. These were grouped into 18 categories, and relative exposure intensities were estimated for 31 different combinations of category and period. The most prevalent exposure in the cohort was pot emissions (fluorides, sulphur dioxide, and carbon monoxide; 74% ever exposed), followed by magnetic fields and heat stress (65-68%), asbestos (40%), and coal tar pitch volatiles (33%). CONCLUSIONS--Although the use of this job-exposure matrix in the subsequent epidemiological studies may result in some misclassification of exposure, this is unlikely to seriously attenuate true risks in a stratified analysis based on cumulative exposure.
Implementation of the precautionary principle in standards for the workplace.
Authors: Stijkel A , Reijnders L
Published: December 2008

The objectives were to describe and discuss the current and proposed European occupational health policy on two categories of substances that pose serious effects: those potentially carcinogenic or genotoxic and those with toxic effects on reproduction. The precautionary principle was applied to setting standards for the workplace for those two categories of substances, to give an impression of the resulting limit values and the consequences of the implementation of this precautionary principle. A pragmatic approach was chosen as this starts with substantial indications of health risks. For the suspected carcinogenic or genotoxic substances 0.1 mg/m3 as a precautionary occupational exposure limit (precautionary OEL) is proposed. For the substances suspected of causing reproductive toxicity the precautionary OEL was derived in three ways, depending on the availability of data and of a current Dutch workplace standard (MAC, maximum accepted concentration): (a) by calculation based on available inhalatory animal data on the risks of reproductive toxicity; (b) by adding a safety factor of 10 to the current MAC, if no inhalatory animal data on reproductive toxicity are available; (c) by using 0.1 mg/m3 as precautionary OEL for substances suspected of having reproductive toxicity but without inhalatory animal data on reproductive toxicity and without a MAC.
Ocular effects of exposure to triethylamine in the sand core cold box of a foundry.
Authors: Reilly M J , Rosenman K D , Abrams J H , Zhu Z , Tseng C , Hertzberg V , Rice C
Published: December 2008

OBJECTIVES--To assess the acute and chronic ophthalmological effects of triethylamine exposure among foundry workers. METHODS--Ocular effects on people currently, previously, and never exposed to triethylamine in a foundry cold box were studied at two points in time. The initial phase included an ocular examination with a slit lamp to assess corneal health, a visual acuity test, and a questionnaire to assess vision symptoms. The follow up included measurements of corneal thickness with an ultrasonic pachymeter and the vision symptoms questionnaire before and after the shift and at the beginning and end of the week. Personal air measurements for triethylamine were also obtained during the follow up. RESULTS--The vision symptoms of blurriness, halos around lights, and blue hazy vision occurred more often in currently exposed workers than those previously or never exposed to triethylamine. Air concentrations of triethylamine ranged from < 0.33 mg/m3 to 20.3 mg/m3. Among currently exposed workers, symptoms were more common among those with exposure to > 10 mg/m3 of triethylamine (odds ratio (OR) = 3.0, 95% confidence interval (95% CI) 0.35-25.6). No differences in corneal thickness were found in currently or previously exposed workers and those never exposed. No increase in corneal thickness was found after v before the shift. CONCLUSION--Despite low concentrations of triethylamine and no corneal oedema, workers exposed to triethylamine reported vision symptoms. Possible explanations for these symptoms without corneal oedema are that triethylamine affects ciliary muscle function or that the corneal oedema was transient and not present when corneal thickness measurements were taken. No chronic effects were found in previously exposed workers. Further research is needed to elucidate the mechanism for the reported vision symptoms, which occurred below the current United States eight hour time weighted standard of 100 mg/m3 and the American Conference of Governmental Industrial Hygienists (ACGIH) recommended value at the time of our study of 40 mg/m3. We recommend that air concentrations be maintained to meet the current recommended ACGIH threshold of 4.1 mg/m3.
Chronic lymphocytic leukaemias and non-Hodgkin's lymphomas by histological type in farming-animal breeding workers: a population case-control study based on job titles.
Authors: Amadori D , Nanni O , Falcini F , Saragoni A , Tison V , Callea A , Scarpi E , Ricci M , Riva N , Buiatti E
Published: December 2008

OBJECTIVES--A population based case-control study was conducted in a highly agricultural area in the north east of Italy to evaluate the association between farming and animal breeding and the risk of developing non-Hodgkin's lymphoma (NHL) and chronic lymphocytic leukaemia (CLL). METHODS--Occupational histories and other data were collected by personal interview on 164 NHLs, 23 CLLs, diagnosed in 1988-90, and on 977 controls. This paper only reports the results of the analysis relative to the coding of job titles through the modified International Labour Office (ILO) classification. Estimates of odds ratios (ORs) for occupational variables were calculated, after adjustment for sex, age, altitude of municipality, first degree familiarity, and previous Herpes zoster infection. RESULTS--From the analysis of the most frequent occupational categories, no occupation showed a significantly high risk. When the two job titles farmers only and farmer-breeders who are also involved in animal breeding are classified within the extremely varied occupation of agriculture or animal-breeding or fishing, a high risk for NHLs and CLLs is seen in the farmer-breeders (OR 1.79, 95% CI 1.22 - 2.63). Analyses according to histological type show that the risks are concentrated in CLLs and in low grade NHLs. No effect or trend by period at work or duration of employment in farming and animal breeding was found. CONCLUSION--Subjects working in agriculture associated with animal breeding are at high risk of NHL/CLLs, particularly CLLs and low grade NHLs. This finding could be related to the use of chemicals in agriculture or to exposure to animal transmitted diseases or specific chemicals used in animal breeding.
Asthmatic symptoms and volatile organic compounds, formaldehyde, and carbon dioxide in dwellings.
Authors: Norbäck D , Björnsson E , Janson C , Widström J , Boman G
Published: December 2008

OBJECTIVES--As a part of the worldwide European Community respiratory health survey, possible relations between symptoms of asthma, building characteristics, and indoor concentration of volatile organic compounds (VOCs) in dwellings were studied. METHODS--The study comprised 88 subjects, aged 20-45 years, from the general population in Uppsala, a mid-Swedish urban community, selected by stratified random sampling. Room temperature, air humidity, respirable dust, carbon dioxide (CO2), VOCs, formaldehyde, and house dust mites were measured in the homes of the subjects. They underwent a structured interview, spirometry, peak expiratory flow (PEF) measurements at home, methacholine provocation test for bronchial hyperresponsiveness, and skin prick tests. In addition, serum concentration of eosinophilic cationic protein (S-ECP), blood eosinophil count, and total immunoglobulin E (S-IgE) were measured. RESULTS--Symptoms related to asthma were more common in dwellings with house dust mites, and visible signs of dampness or microbial growth in the building. Significant relations were also found between nocturnal breathlessness and presence of wall to wall carpets, and indoor concentration of CO2, formaldehyde, and VOCs. The formaldehyde concentration exceeded the Swedish limit value for dwellings (100 micrograms/m3) in one building, and CO2 exceeded the recommended limit value of 1000 ppm in 26% of the dwellings, showing insufficient outdoor air supply. Bronchial hyperresponsiveness was related to indoor concentration of limonene, the most prevalent terpene. Variability in PEF was related to two other terpenes; alpha-pinen and delta-karen. CONCLUSION--Our results suggest that indoor VOCs and formaldehyde may cause asthma-like symptoms. There is a need to increase the outdoor air supply in many dwelling, and wall to wall carpeting and dampness in the building should be avoided. Improved indoor environment can also be achieved by selecting building materials, building construction, and indoor activities on the principle that the emission of volatile organic compounds should be as low as reasonably achievable, to minimise symptoms related to asthma due to indoor air pollution.
Polyneuropathy induced by carbon disulphide in viscose rayon workers.
Authors: Chu C C , Huang C C , Chen R S , Shih T S
Published: December 2008

OBJECTIVES--To understand the prevalence of polyneuropathy and correlations among the clinical manifestations, electrophysiological findings, and degree of exposure to carbon disulphide (CS2) in workers who were exposed to variable concentrations of CS2 in a viscose rayon factory. METHODS--All the 163 workers received a detailed physical and neurological evaluation. Fixed point air samples were analysed for CS2. Nerve conduction velocity was studied in 26 workers with symptoms similar to neuropathy. RESULTS--Nine workers (53%) with overt polyneuropathy from the fibre cutting department and 19 workers (13%) with oligosymptoms similar to polyneuropathy from various jobs were noted. The fixed point air concentrations of CS2 were 150-300 ppm in the cutting areas and 15 to 100 ppm in the spinning areas. The estimated eight hour time weighted averages in the fibre cutting areas were 40-67 ppm. The occurrence of polyneuropathy was generally correlated with the degree of exposure to CS2. Nerve conduction velocities (NCVs) were significantly different in the overt polyneuropathy and subclinical polyneuropathy groups from the normal controls. The sensitive indicators for CS2 polyneuropathy were distal latency, motor NCV, and amplitude of sensory nerve action potentials in sensory NCVs. CONCLUSION--The outbreak of polyneuropathy was attributed to higher concentrations of CS2 in fibre cutting areas. Even in other jobs with relatively lower concentrations of CS2, the hazard of subclinical polyneuropathy cannot be overlooked.
Electroencephalographic study of divers with histories of neurological decompression illness.
Authors: Murrison A W , Glasspool E , Pethybridge R J , Francis T J , Sedgwick E M
Published: December 2008

OBJECTIVE--To determine whether divers with histories of neurological decompression illness are electroencephalographically distinguishable from non-divers. METHODS--The electroencephalograms (EEGs) from 68 divers with histories of neurological decompression illness and 45 non-diver controls were examined independently by two clinical neurophysiologists. RESULTS--The diver and non-diver groups were electroencephalographically indistinguishable. CONCLUSION--There is no electroencephalographic evidence for the existence of cerebral dysfunction in divers with histories of decompression illness.
Bladder cancer among French farmers: does exposure to pesticides in vineyards play a part?
Authors: Viel J F , Challier B
Published: December 2008

OBJECTIVE--To appraise the potential contribution of pesticides sprayed on vineyards to the genesis of bladder cancer among agricultural workers. METHODS--A pesticide exposure index (PEI), based on labour time and the proportion of agricultural land used as vineyards, was constructed for 89 French geographical units (départements). The standardised mortality ratios (SMRs) for bladder cancer, as well as tobacco consumption and economic status of male farmers and farm labourers aged 35-74 in the same areas were estimated for the period 1984-6. Models were fitted to the geographical data with Poisson regressions and extra-Poisson models with geographically structured and unstructured random effects. RESULTS--Mortality from bladder cancer among farmers was lower (but not significantly so) than within the overall population (SMR 0.96, 95% confidence interval (95% CI) 0.85-1.08), but there was a significant link with exposure to pesticides in vineyards by univariate analysis (relative risk (RR) 1.17, 95% CI 1.10-1.24) and by multivariate analysis (RR 1.14, 95% CI 1.07-1.22). CONCLUSION--These results add some evidence to the view that pesticides in vineyards cause mortality from bladder cancer among farmers, and could explain the French south-north gradient in bladder cancer, as vineyards are mainly located in Southern France.
Exposure to polycyclic aromatic hydrocarbons in coal liquefaction workers: impact of a workwear policy on excretion of urinary 1-hydroxypyrene.
Authors: Quinlan R , Kowalczyk G , Gardiner K , Calvert I
Published: December 2008

OBJECTIVE--This study was undertaken to assess whether contaminated personal clothing worn beneath a coverall (normal workwear) is a source of potentially significant dermal exposure to polycyclic aromatic hydrocarbons (PAHs) in coal liquefaction workers. METHODS--An intervention study was conducted over a two week period involving 10 workers that reflected the range of activities performed at the factory. A cross over design was used to examine the influence of normal workwear (personal clothing worn beneath a coverall) and intervention workwear (new coverall, shirt, trousers, underwear, socks, and boots) upon excretion of urinary 1-hydroxypyrene (1-OHP) and skin pad deposition of pyrene. RESULTS--The impact of intervention was noted in three ways: (1) A notable reduction (55%) in the mass of 1-OHP excreted on the first day of the intervention phase was found. The median reduction in mass excreted (22.7 nmol) was significant from zero at the 5% level; (95% confidence interval (95% CI) 9.5-40.8 nmol). (2) A notable reduction (82%) in skin pad deposition of pyrene on the first day of the intervention phase was found. The median reduction of 13.20 ng.cm-2 was significant from zero at the 5% level; (95% CI 7.3-26.4 ng.cm-2). (3) About a 50% reduction in 1-OHP concentration over the working week occurred during the intervention phase; an increase of 2.07 mumol/mol creatinine was found from the start to the end of the work period during the intervention phase compared with an increase of 4.06 mumol/mol creatinine during the normal phase. This reduction was not significant at the 5% level. CONCLUSION--The results indicate that on the first day of the working week investigated, significant reductions in absorbtion (as measured by excretion of urinary 1-OHP) and deposition of PAHs (as measured by skin pad deposition of pyrene) can be effected by improvements in workwear policy. The impact of the improved workwear regimen was also detected by reduction in spot urinary 1-OHP concentrations, although this effect was less pronounced. One implication of the findings is that exposure to PAHs may arise from workers' own contaminated personal clothing. As a consequence of this study an improved workwear policy has been implemented at the factory.
Enzyme immunoassays for total and allergen specific IgE in population studies.
Authors: Doekes G , Douwes J , Wouters I , de Wind S , Houba R , Hollander A
Published: December 2008

OBJECTIVE--Extensive IgE serology in occupational or environmental health studies is often hampered by a lack of technical facilities and finance. The use in population studies of relatively simple and inexpensive enzyme immunoassays (EIAs) was therefore evaluated for the assessment of total serum immunoglobulin E (IgE), and of specific IgE reactions with various common (house dust mites, grass and birch pollen, and cat) or occupational (fungal alpha-amylase and rat urinary protein) allergens. METHODS--Total IgE was measured with a sandwich EIA, calibrated with commercially available IgE standards. Reproducibility was studied by testing pooled normal human serum samples in each of a large series of test plates. A panel of 156 children's serum samples with known IgE values was used to compare the assay with other total IgE assays. A previously developed EIA for anti-yeast IgE was adapted for the measurement of IgE reacting with various common and occupational allergens. Binding of IgE to microwells coated with commercially available allergen extracts, or allergen preparations from our own laboratory, was measured with a monoclonal anti-human IgE antibody and subsequent incubations with biotinylated rabbit anti-mouse Ig and avidin-peroxidase. Panels of serum samples from school children (n = 116), bakery workers (n = 126), and laboratory animal workers (n = 52) were used to study sensitivity and specificity, with reference to skin prick tests as the standard, and to compare the EIAs with commercially available test kits. RESULTS--The detection limit of the EIA for total IgE was 0.5-1 kU/l for undiluted serum samples, and the coefficient of variation between assays was less than 15% at serum concentrations between 1 and 150 kU/l. Results obtained with the panel of 156 children's serum samples were strongly correlated (r2 = 0.86) with IgE concentrations measured previously by radioimmunoassay. The results of the EIA for various occupational allergens correlated very well, both qualitatively and quantitatively, with the results of commercial test kits. Sensitivity and specificity of the EIA results as a predictor of skin prick test reactivity towards common allergens (house dust mite, grass pollen, birch pollen, and cat) were remarkably high (> 80%-90%) in the series of 116 children's serum samples. In a population of bakery workers the specificity of the EIAs was also very high (> 90%). The sensitivity was notably lower (30%-70%) in this adult population, which is, however, in agreement with results reported for conventional IgE tests. CONCLUSION--As the costs were estimated to be at least five to 10-fold lower than those of commercial test kits, the EIAs for total and specific IgE may be very useful tools in epidemiological studies of atopic respiratory or other disorders.
Effects on symptoms and lung function in humans experimentally exposed to diesel exhaust.
Authors: Rudell B , Ledin M C , Hammarström U , Stjernberg N , Lundbäck B , Sandström T
Published: December 2008

OBJECTIVES: Diesel exhaust is a common air pollutant made up of several gases, hydrocarbons, and particles. An experimental study was carried out which was designed to evaluate if a particle trap on the tail pipe of an idling diesel engine would reduce effects on symptoms and lung function caused by the diesel exhaust, compared with exposure to unfiltered exhaust. METHODS: Twelve healthy non-smoking volunteers (aged 20-37) were investigated in an exposure chamber for one hour during light work on a bicycle ergometer at 75 W. Each subject underwent three separate double blind exposures in a randomised sequence: to air and to diesel exhaust with the particle trap at the tail pipe and to unfiltered diesel exhaust. Symptoms were recorded according to the Borg scale before, every 10 minutes during, and 30 minutes after the exposure. Lung function was measured with a computerised whole body plethysmograph. RESULTS: The ceramic wall flow particle trap reduced the number of particles by 46%, whereas other compounds were relatively constant. It was shown that the most prominent symptoms during exposure to diesel exhaust were irritation of the eyes and nose and an unpleasant smell increasing during exposure. Both airway resistance (R(aw)) and specific airway resistance (SR(aw)) increased significantly during the exposures to diesel exhaust. Despite the 46% reduction in particle numbers by the trap effects on symptoms and lung function were not significantly attenuated. CONCLUSION: Exposure to diesel exhaust caused symptoms and bronchoconstriction which were not significantly reduced by a particle trap.
Enzyme exposure and enzyme sensitisation in the baking industry.
Authors: Vanhanen M , Tuomi T , Hokkanen H , Tupasela O , Tuomainen A , Holmberg P C , Leisola M , Nordman H
Published: December 2008

OBJECTIVES: To assess the exposure to enzymes and prevalence of enzyme sensitisation in the baking industry. METHODS: A cross sectional study was conducted in four bakeries, one flour mill, and one crispbread factory. Sensitisation to enzymes, flours, and storage mites was examined by skin prick and radioallergosorbent (RAST) tests. 365 workers were tested. The workers were interviewed for work related respiratory and skin symptoms. Total dust concentrations were measured by a gravimetric method, and the concentration of alpha-amylase in air was measured by a catalytic method. An immunochemical method was used for measuring cellulase and xylanase in air. RESULTS: Total measured dust concentrations were from 0.1 to 18 mg/m3, with highest values in dough making areas of bakeries. The alpha-amylase concentrations generally followed the total dust concentrations and reached the highest values < 6.6 micrograms/m3 in the same areas. Cellulase and xylanase varied with concentrations < 180 ng/m3 and < 40 ng/m3, respectively, in the flour mill and the crispbread factory. No cellulase, but concentrations of 1-200 ng/m3 xylanase, were found in the bakeries, probably indicating the natural xylanase activity of wheat. 12 workers (8%) in the bakeries, three (5%) in the flour mill, and four (3%) in the crispbread factory were skin prick positive to enzymes. The corresponding percentages of positive reactions to flours were 12%, 5%, and 8%. CONCLUSIONS: The study confirmed that industrial enzymes in baking used as additives in a powdered form pose a risk of sensitisation. The no effect air concentrations for industrial enzymes are not known. Based on present knowledge, however, lowering exposures and eliminating short and high peaks by technical measures would lower the risk of sensitisation. This would be most effectively accomplished by shifting to non-dusty products.