Back disorders and nonneutral trunk postures of automobile assembly workers.

A case-referent study was conducted in an automobile assembly plant to evaluate the health effect of trunk postures, such as bending and twisting, that deviate from anatomically neutral. Cases of back disorders were all those of workers who reported back pain to the medical department in a ten-month period and met the severity criteria of an interview. The referents were randomly selected workers free of back pain according to medical department records, an interview, and an examination. For each of the final 95 cases and 124 referents, the job was analyzed for postural and lifting requirements with a video recording and software analysis system by analysts blinded to the case/referent status. Back disorders were associated with mild trunk flexion [odds ratio (OR) 4.9, 95% confidence interval (95% CI) 1.4-17.4], severe trunk flexion (OR 5.7, 95% CI 1.6-20.4), and trunk twist or lateral bend (OR 5.9, 95% CI 1.6-21.4). The risk increased with exposure to multiple postures and increasing duration of exposure.     

Risk factors for work-related musculoskeletal disorders in an aluminum smelter

A cross-sectional study of selected jobs in an aluminum smelter was conducted to assess the prevalence of work-related musculoskeletal disorders (WMDs), and to estimate their association with physical and psychosocial characteristics of the jobs. A structured interview and physical exam were used to assess the musculoskeletal health status of the participants, and a self-administered questionnaire was used to assess the psychosocial factors. Observational job analysis was conducted to evaluate 37 potential physical risk factors. Complete data were available for 104 subjects. The prevalence of WMDs on interview and physical exam were 0.8%, 14.9%, 11.6%, 14.9%, and 17.4% for the neck, shoulder, elbow/forearm, hand/wrist, and low back regions, respectively. Unconditional multiple logistic regression was used to model the relationship between physical and psychosocial factors and health status. Years of forearm twisting were found to be a significant predictor for hand/wrist disorders on interview (OR = 17, 95% CI = 2.9–106); for elbow/foream disorders on physical exam and interview (OR = 37, 95% CI = 3.0–470); and for shoulder disorders on interview (OR = 92, 95% CI = 7.3–∞) and on interview and physical exam (OR = 46, 95% CI = 3.8–550). Low decision latitude was also found to be significant for the shoulder on interview (OR = 4.5, 95% CI = 1.3–16). High job satisfaction (OR = 5.9, 95% CI = 1.4–25) and low social support (OR = 5.3, 95% CI = 1.3–22) were associated with low back pain report on interview; only high job satisfaction (OR = 5.3, 95% CI = 1.1–26) was associated with low back pain on both interview and physical exam. Am. J. Ind. Med. 32:66-75, 1997. © 1997 Wiley-Liss, Inc.     

Occupational risk factors for lung cancer among young men

OBJECTIVES: This study evaluated whether occupational exposure plays a role for lung cancer at a very young age. METHODS: In a pooled analysis of 2 German case-referent studies including 3498 incident cases among men and 3541 male population referents, a group of men (187 cases and 202 referents) aged > or =45 years was compared with a group of 2186 cases and 2146 referents aged 55-69 years. Occupational exposure to known (A list) or suspected (B list) lung carcinogens was assessed using job and industry codes, and exposure to asbestos was assessed using job-specific supplementary questionnaires. A conditional logistic regression was used to calculate the odds ratios (OR) and to control for smoking. RESULTS: Asbestos exposure showed an odds ratio (OR) of 2.39 [95% confidence interval (95% CI) 1.41-4.04] for the younger group and 1.46 (95% CI 1.24-1.72) for the older group. Having ever worked in a job belonging to the A list as compared with never working in an A- or B-list job was associated with a significantly increased risk for the younger (OR 2.06, 95% CI 1.03-4.12) and older (OR 1.35, 95% CI 1.10-1.65) groups, adjusted for asbestos. Lung cancer risk for those working in A-list jobs at a very young age (under 16 years) was increased in the younger group (OR 6.14, 95% CI 1.41-28.01) in contrast to the older group (OR 1.19, 95% CI 0.91-1.63). CONCLUSION: Occupational risk factors play an important role for lung cancer among young men. Early age at first exposure may favor an early age of the onset of lung cancer.     

Risk of shoulder tendinitis in relation to shoulder loads in monotonous repetitive work.

BACKGROUND: Few studies relate the occurrence of shoulder disorders to quantified ergonomic exposures. This study evaluates the hypothesis that shoulder loads in repetitive work might contribute to the occurrence of shoulder tendinitis. METHODS: This is a cross-sectional study of 1961 workers in repetitive work and 782 referents. Shoulder loads were quantified at task level and measures of exposures were assigned based on task distribution. Symptoms in combination with clinical criteria defined shoulder tendinitis. RESULTS: The prevalence of shoulder tendinitis was higher among exposed workers (adjusted OR 3.1, 95% CI 1.3-3). Neither frequency of movements (ranging 1-36/min) nor lack of micro-pauses in shoulder flexion (ranging 0-100% of cyclus time) was related to disease prevalence. Increasing force requirements (categorized as light = 1, somewhat hard = 2, hard = 3 or very hard = 4) increased risk slightly (OR 1.6, 95% CI 1.0-2.6 per unit). CONCLUSIONS: The results indicate that workers with repetitive tasks have increased risk of shoulder tendinitis, which partially can be attributed to force requirements.     

Interview versus questionnaire for assessing physical loads in the population-based MUSIC-Norrtälje Study

BACKGROUND: MUSIC-Norrt?lje study is a case-referent study, the aim of which is to find risk and health factors for low back and neck/shoulder disorders. In this part of the study, the interview technique and the self-administered questionnaire used for assessment of physical loads are described and the inter-method reliability of parts of the self-administered questionnaire is estimated. The distribution of exposure levels in a general population is also described. METHODS: The study period was three years from November 1993 to November 1996, and the study subjects totaled 2,480 persons (813 female and 610 male referents, 380 female and 315 male low back cases, 252 female and 106 male neck/shoulder cases). The interview concerned "a typical working day" during the preceding 12 months and comprised assessment of energy expenditure, work postures, and manual materials handling for work and leisure time, including regular sport activities. The self-administered questionnaire comprised 18 questions, each covering 5 different points of time: right now, 5, 10, 15, 20 years ago. The answers to eight of the questions about current conditions were compared to corresponding interview responses. The interview was considered as the "gold standard." RESULTS: Ninety-eight percent of the subjects completed the interview without any great difficulties. According to the interview, the distributions of different exposure levels were generally positively skewed, i.e., the frequency of highly exposed subjects was low in the study base. The correlation between interview and questionnaire responses among the referents was high for time spent "sitting at work" (r = 0.82), "VDU work" (r = 0.87), and work related "motor vehicle driving" (r = 0.80). The correlation was moderate for work-related "hands above shoulder level" (rs = 0.63), and "hands below knee level (trunk flexion)" (rs = 0.66). The correlation was lower for leisure time activities such as "domestic work" (r = 0.55), "time for own activities" (r = 0.39), and "sitting during leisure time" (r = 0.38). Subjects seeking care for low back or neck/shoulder disorder estimated equally correctly or not, as had the referents. However, non-differential misclassification was present in all questions, which will attenuate observed estimates of the relative risk. CONCLUSIONS: Even though interview data are preferable, questionnaire data may be useful for assessing well-defined work tasks and for "sitting at work."     

Mental retardation and parental occupation: a study on the applicability of job exposure matrices.

In a case-referent study on mental retardation and parental occupation, the applicability of job exposure matrices for the identification of risk factors was evaluated. The parents of 306 mentally retarded children (cases) and 322 referents were interviewed about their occupational activities in the pregnancy period. Detailed occupational histories were obtained that were compared with exposures generated by two different job exposure matrices. The agreement between interview and matrices was low: the sensitivity ranged from 17.9% to 32.4% and the percentages of false positive exposures from 66.7% to 96.0%. By means of the interview, significantly increased odds ratios (ORs) were found for exposure of the mother in late pregnancy to radiation (OR = 9.3), mercury (OR = 8.7), organic solvents (OR = 1.7), hair cosmetics and dyes (OR = 3.7), paint (OR = 2.7), hexachlorophene/phenylphenol (OR = 3.1), antibiotics (OR = 2.9), and dust (OR = 2.2) and for working with copying machines (OR = 3.0) or in occupations with poor climatological circumstances and permanent contact with people. The last was confirmed by the British matrix (OR = 1.7). Otherwise, most of the mentioned associations were missed by the job exposure matrices. Therefore, these matrices were not considered to be applicable in this particular study, nor in most other reproductive epidemiological studies in view of their general properties and limitations.     

Primary osteoarthrosis of the knee in men and women as a result of lifelong physical load from work

OBJECTIVES: This study investigated the effect of lifelong physical load from work on the development of knee osteoarthrosis (OA) leading to prosthetic surgery among men and women. METHODS: In a population-based case-referent study, men and women (N=625) who had had prosthetic surgery due to primary tibiofemoral OA were compared with referents (N=548) as to job titles and exposure to physical load in occupational work, housework, and leisure-time activities from 15 to 50 years of age. RESULTS: Male forestry and construction workers, and both male and female farmers ran the highest risk of knee OA. The men had considerably higher exposure to lifting at work, and also to jumps and vibration, than the women. Among the men there was an association between lifting at work [odds ratio (OR) 3.0, 95% confidence interval (95% CI) 1.6-5.5], squatting or knee bending (OR 2.9, 95% CI 1.7-4.9), kneeling (OR 2.1, 95% CI 1.4-3.3), and jumping (OR 2.7, 95% CI 1.7-4.1) with knee OA. Exposure to physically demanding tasks at home, such as taking care of an elderly or handicapped person, was associated with knee OA among the women (OR 2.2, 95% CI 1.3-3.6). CONCLUSIONS: Working as a farmer or as a construction worker could be associated with the development of knee OA and lead to prosthetic surgery. Men and women differ in the quality and quantity of reported physical load and also in the strength of the risk estimates. A reduction of high physical load at work and at home could probably lower the risk of knee OA later in life.     

Cytogenetic and morphologic subgroups of myelodysplastic syndromes in relation to occupational and hobby exposures

OBJECTIVES: This study investigated the association between occupational and hobby exposure and the risk of myelodysplastic syndromes (MDS) while focusing on differential patterns of clonal chromosome aberrations and morphologic subgroups. METHODS: A case-referent study was conducted with 330 MDS patients investigated cytogenetically in 1976-1993 (cases) and matched referents. Telephone interviews with either the person or a next-of-kin were used. The participation rate of the cases and referents was 85% and 60%, respectively. Information was obtained from the next-of-kin more often for the cases (88%) than for the referents (26%). Occupational hygienists assessed the exposure using interview data on worktasks and hobbies. Associations with disease risk were evaluated for 10 exposures with a logistic regression analysis. RESULTS: The investigated exposures were generally not associated with cytogenetically abnormal MDS. Effect estimates for specific cytogenetic or morphologic subgroups were generally imprecise. Occupational exposure to extremely low-frequency magnetic fields (EMF) was associated with MDS with a normal karyotype [odds ratio (OR) 2.0, 95% confidence interval (95% CI) 1.0-4.0]. The exposure-response association was consistent for intensity but inconclusive for duration. A decreased risk was observed for MDS, irrespective of karyotypic pattern, among farmers and farmhands (OR 0.53, 95% CI 0.35-0.81). CONCLUSIONS: Cytogenetically abnormal MDS was generally not associated with occupational or hobby exposure to known or suspected genotoxic agents. However, exposure prevalences and intensities were low for several agents. An association was suggested between occupational exposure to EMF and MDS with a normal karyotype. Biases due to differential information quality and selective participation cannot be ruled out.     

Physical workload and the risk of severe knee osteoarthritis

OBJECTIVES: This study investigated the impact of physical workload on the risk of severe knee osteoarthritis (OA) leading to knee arthroplasty. METHODS: In this case-referent study, the cases were 55- to 75-year-old men (N=55) and women (N=226) who had undergone their first knee arthroplasty operation for primary knee OA in the Kuopio University Hospital in 1992-1993. The referents (N=524) were from the same source population and were matched with the cases for age and gender. Information on explanatory variables was obtained by a computer-assisted telephone interview. Exposure was assessed up to 49 years of age. RESULTS: After adjustment for body mass index, knee injury and leisure-time physical activity, an increased relative risk of knee OA was found for a history of high physical workload. The odds ratio (OR) was 1.53 [95% confidence interval (95% CI) 0.42-5.56] for the men and 2.03 (95% CI 1.03-3.99) for the women as compared with those with low physical workload. With respect to generic risk factors, climbing already at a medium level of exposure was associated with an increased risk of knee OA among the men (OR 3.06, 95% CI 1.25-7.46) and kneeling and squatting was a risk factor for both genders. Of the different trades, agriculture, forestry, fishing, transportation, and traffic showed the highest risks of knee OA. CONCLUSIONS: The results of this study agree with the hypotheses that heavy physical loading increases the risk of knee OA and that cumulative physical stress has a deleterious effect on the knee joint.     

Gastrointestinal cancer among cement workers

Summary A matched case-referent study was conducted to investigate the risk of gastrointestinal cancer in cement workers. All male cases of cancer in esophagus, stomach, colon and rectum in the period 1922–1988 from two parishes surrounding a cement plant were identified. For each case, four referents were chosen, matched to age and year of death. Employment in the cement plant was confirmed as from plant records or job title noted in the parish books. Of 25 cases with a definite colorectal tumour, 40% had been blue-collar cement workers for 25 years or more, compared with 20% of their referents [odds ratio (OR) 3.2; 95% confidence limits (CI) 1.1–9.4]. There were indications of a dose (time of employment)-response relationship. For 18 cases with an esophageal or stomach tumour, the OR for those ever employed as cement workers was 3.2 (CI 1.0–11), but short-term employment predominated, thus making a causal relationship less likely.     

Coxarthrosis and physical work load

A case-referent study was performed on the possible relationship between physical work loads and an increased risk of developing coxarthrosis. The cases were 239 male recipients of a hip prosthesis as a result of severe idiopathic coxarthrosis; the referents were 302 men randomly selected from the general population. The work load was assessed through an interview and a self-administered questionnaire on the men's specific work periods. Men highly exposed to dynamic or static work loads had an increased relative risk of 2.42 (95% confidence interval 1.45-4.04) for developing coxarthrosis when compared with men with low exposure. Men with high exposure to heavy lifting between the ages of 30 and 49 years had the highest relative risk, 3.31 (95% confidence interval 1.97-5.57). Long-time exposure to physical work loads seems to be a risk factor for severe coxarthrosis among men.     

Occupation as a risk factor for uveal melanoma in Germany

OBJECTIVE: This study explored occupational risks linked to uveal melanoma. METHODS: The analysis pooled data from two case-referent studies (hospital- and population-based) conducted in Germany between 1995 and 1998, with incident cases matched with several referents by age, gender, and region of residence. The subjects were contacted through personal or telephone interviews. Their exposure status was based on their occupational history. Dichotomous coding for the main task and categorization into different occupational classification systems was performed. Altogether of 118 cases and 475 referents were included. Adjusted odds ratios were calculated by conditional logistic regression. RESULTS: Relevant occupations included food, beverage, and tobacco processors [odds ratio (OR) 4.7, 95% confidence interval (95% CI) 0.99-22.0] and miners (OR 2.3, 95% CI 0.92-5.99) among the men and station, engine and heavy equipment operators and freight handlers (OR 2.5, 95% CI 0.94-6.58) and medical, dental, pharmaceutical and veterinary workers (OR 2.1, 95% CI 0.71-6.02) among the women according to the International Standard Classification of Occupations, whereas, according to the European Industrial Classification, the relevant occupations were the food industry (OR 3.4, 95% CI 1.08-10.5) and the chemical and pharmaceutical industry (OR 2.8, 95% CI 1.01-7.78) among the men and machine production (OR 3.2, 95% CI 0.96-10.7) and health and veterinary sector (OR 2.4, 95% CI 0.97-5.71) among the women. CONCLUSIONS: These analyses support the potential role of occupational exposure as a risk factor for uveal melanoma. The findings must be interpreted carefully since the exposure was assessed indirectly.     

Occupation and the risk of laryngeal cancer in Turkey

OBJECTIVES: A hospital-based case-referent study was conducted in Turkey to provide further information on occupational risk factors and laryngeal cancer. METHODS: Among 7631 cancer cases seen at an oncology treatment center between 1979 and 1984, 958 laryngeal cancer cases were identified among men. Occupational history, tobacco and alcohol use, and demographic data were obtained from patients with a standardized questionnaire. Special 7-digit standard occupational and industrial codes were created to classify the job and industrial titles of the subjects. After exclusions, 940 laryngeal cancer cases and 1519 referents were available for study. Age-, smoking- and alcohol-adjusted odds ratios (OR) and 95% confidence intervals (95% CI) were calculated. RESULTS: Excess laryngeal cancer occurred among guards (OR 1.5, 95% CI 1.1-2.1), production supervisors (OR 1.8, 95% CI 1.1-3.1), textile workers (OR 1.9, 95% CI 1.2-3.3), drivers (OR 1.7, 95% CI 1.1-2.4), construction workers (OR 1.7, 95% Cl 1.2-2.6), and workers in grain mills (OR 3.1, 95% CI: 1.3-7.6), trade unions (OR 3.6, 95% CI: 1.1-11.7) and local government services (OR 4.7, 95% CI 1.7-12.5). Supraglottic cancer was excessive among the textile workers, construction workers, and local government laborers, all with potential dust exposure. The risks of the general managers, electricians, and workers from industries such as pharmaceutical production, industrial machinery production, electric utilities, and retail services were lower than expected. CONCLUSIONS: The risk of laryngeal cancer was associated with several occupations, and supraglottic larynx cancer appears to be more common among workers in dusty occupations and industries.     

The association of socioeconomic status and psychosocial and physical workplace factors with musculoskeletal injury in hospital workers

BACKGROUND: The combined effect of socioeconomic, organizational, psychosocial, and physical factors on work-related musculoskeletal disorders (WRMSDs) were studied in a heterogeneous, socioeconomically diverse sample (cases and their matched referents) of hospital workers. METHODS: Cases were defined by a new acute or cumulative work-related musculoskeletal injury; referents were matched by job group, shift length, or at random. Information was obtained through telephone interviews and on-site ergonomics observation. Questionnaire items included sociodemographic variables, lost work time, work effectiveness, health status, pain/disability, and psychosocial working conditions using Effort Reward Imbalance (ERI) and Demand-Control (DC) models. Two multivariate models were tested: Model 1 included occupation as a predictor; Model 2 included education-income as a predictor. RESULTS: Cases reported greater pain, disability, lost time, and decreased work effectiveness than the referents. Model 1 was statistically significant for neck/upper extremity injury (Chi-square = 19.3, P = 0.01), back/lower extremity injury (Chi-square = 14.0, P = 0.05), and all injuries combined (Chi-square = 25.4, P = 0.001). "Other Clinical" occupations (34% mental health workers) had the highest risk of injury (OR 4.5: 95%CI, 1.7-12.1) for all injuries. The ERI ratio was a significant predictor for neck and upper extremity (OR 1.5: 95%CI, 1.1-1.9) and all injuries (OR 1.3; 95%CI, 1.04-1.5), per SD change in score. CONCLUSIONS: In this study, the risk of WRMSDs was more strongly influenced by specific psychosocial and physical job-related exposures than by broad socioeconomic factors such as education and income.     

Work-related psychosocial and mechanical risk factors for neck/shoulder pain: a 3-year follow-up study of the general working population in Norway

Purpose

This study examines the impact of work-related psychosocial and mechanical exposure on the development of neck/shoulder pain in the general working population.

Methods

A randomly drawn cohort from the general population in Norway aged 18–66 was followed up for 3 years (n = 12,550, response rate = 67 %). Eligible respondents were in paid work during the reference week in 2006 and 2009, or temporarily absent from such work (n = 6,745). Four work-related psychosocial factors and six mechanical exposures were measured. Outcomes of interest were moderate or severe neck/shoulder pain at follow-up adjusted for baseline neck/shoulder pain.

Results

In total, 16.9 % (1,138 individuals) reported neck/shoulder pain during the last month at follow-up. Work related psychosocial predictors of neck/shoulder pain were high job demands (highest OR 1.41, 95 % CI 1.11–1.78) and low levels of supportive leadership (highest OR 1.66, 95 % CI 1.08–2.54). Mechanical factors were neck flexion (highest OR 1.77, 95 % CI 1.31–2.39) and lifting in awkward postures (highest OR 1.81, 95 % CI 1.21–2.71). The estimated population risk attributable to these factors was about 23 %. The relative risk for neck/shoulder pain associated with psychosocial exposure was slightly influenced by adjustment for physical risk factors, and vice versa. There was no substantial confounding related to age, gender, education, occupation or psychological distress.

Conclusions

Highly demanding jobs, neck flexion and awkward lifting appear as the most important predictors of neck/shoulder pain.     

Occupation and cancer of the oral cavity or oropharynx in Turin, Italy

In a population-based case-referent study, the occupational experience of 86 men with oral or oropharyngeal cancer and 373 referents was analyzed with respect to employment in 41 occupations and 40 industries, as well as to exposure to 16 chemicals, as estimated via a job-exposure matrix. Among the occupations and industries at higher risk were machinery operator (odds ratio [OR] 2.0; 95% confidence interval [95% CI] 1.0-4.0), plumber (OR 5.0, 95% CI 1.2-21.5), building industry (OR 2.5; 95% CI 1.3-4.5), textile industry (OR 2.5; 95% CI 0.6-4.6), and electricity production (OR 2.8; 95% CI 0.7-12.1). All the OR estimates were adjusted for age, education, area of birth, tobacco smoking, and alcohol consumption. An association between formaldehyde exposure and oral cancer was suggested (OR for any exposure 1.6, 95% CI 0.9-2.8; OR for probable or definite exposure 1.8, 95% CI 0.6-5.5). No other chemical included in the matrix showed any risk pattern. The evidence of an association between formaldehyde exposure and oral or oropharyngeal cancer is strengthened by the results of this study.     

Occupational dust exposure and the risk of laryngeal cancer in Turkey

OBJECTIVES: A hospital-based case-referent study was conducted to identify occupational risk factors for laryngeal cancer. In a previous report an association was found between laryngeal cancer and occupations with potential dust exposure; a job-exposure matrix was developed to aid further evaluation of laryngeal cancer risks from five occupational dust exposures. METHODS: Among 7631 cancer cases from the Okmeydani Hospital, Istanbul, between 1979 and 1984, 958 larynx cancer cases were identified among men. After exclusions, 940 laryngeal cancer cases and 1519 referents were available. A standardized questionnaire was used to obtain basic information on the patients. Seven-digit standard occupational and industrial codes were created to classify the job and industrial titles. A job-exposure matrix was developed for occupational dusts, including silica, asbestos, wood, cotton, and grain, and age-, smoking-, and alcohol-adjusted odds ratios (OR) and 95% confidence intervals (95% CI) were calculated to evaluate risks of laryngeal cancer. RESULTS: An excess of laryngeal cancer occurred for workers potentially exposed to silica and cotton dust, particularly for supraglottic cancer (OR 1.8, 95% CI 1.3-2.3, for silica and OR 1.6, 95% CI 1.1-2.5, for cotton dust), and there was a significant dose-response relationship with silica exposure. No relationship was found between laryngeal cancer and asbestos, grain, or wood dust exposures. CONCLUSION: Laryngeal cancer, especially supraglottic tumors, is associated with silica and cotton dust exposures in Turkey.     

Osteoarthritis of the hip and occupational activity.

This case-referent study investigated the relation between hip osteoarthritis and occupational activity. The subjects were 60- to 75-year-old men who had undergone intravenous urography. Interviews were obtained for 245 cases who had a hip replacement for osteoarthritis or a joint space of less than or equal to 2.5 mm and 294 referents whose joint space was greater than or equal to 3.5 mm in both hips. No clear associations were found in an analysis of all the cases, but severe disease (hip replacement for osteoarthritis or a joint space of less than or equal to 1.5 mm) was more common in the farmers, especially in those with greater than or equal to 10 years in agricultural work [odds ratio (OR) 2.0, 95% confidence interval (95% CI) 0.9-4.4]. Severe disease was also associated with prolonged standing at work (OR 2.7, 95% CI 1.0-7.3) and heavy lifting (OR 2.5, 95% CI 1.1-5.7). These associations could not be explained by obesity or sporting activity. The findings suggest an increased risk of degenerative hip disease for farmers and indicate that mechanical overloading may contribute to its pathogenesis.     

Prevalence of work related musculoskeletal disorders in active union carpenters

OBJECTIVES: To determine the prevalence and risk factors for work related musculoskeletal disorders among union carpenters. METHODS: A detailed questionnaire on musculoskeletal symptoms and work history was administered to 522 carpenters. The symptom questions assessed if carpenters experienced pain, numbness, or tingling in a particular body region. A subset of this group then received a physical examination of the upper extremities and knees. RESULTS: The study group was primarily white (94.9%) and male (97.8%) with a mean age of 42.3 years. The highest prevalence of work related musculoskeletal disorders cases by carpentry specialty ranged from 20%-24% for those doing drywall or ceiling, finishing or framing, and the building of concrete forms. Generally, as duration of employment increased, the prevalence of symptoms increased. An adjusted logistic regression analysis showed that the group with the longest (> or = 20 years) duration of employment in carpentry was significantly associated with work related musculoskeletal disorders of the shoulders (odds ratio (OR) 3.2, 95% confidence interval (95% CI) 1.1 to 8.9), hands or wrists (OR 3.1, 95% CI 1.1 to 8.4), and knees (OR 3.5, 95% CI 1.3 to 9.2). Also, analyses showed that carpenters who reported that they had little or no influence over their work schedule had significant increases of work related musculoskeletal disorders of the shoulders, hips, and knees with ORs of 1.9 (95% CI 1.1 to 3.2), 2.9 (95% CI 1.1 to 7.2), and 2.3 (95% CI 1.2 to 4.1), respectively. Feeling exhausted at the end of day was also a significant risk factor for work related musculoskeletal disorders of the knee (OR 1.8, 95% CI 1.1 to 3.1). Upper extremity disorders were the most prevalent work related musculoskeletal disorders reported among all carpenters. Drywall or ceiling activities involve a considerable amount of repetitive motion and awkward postures often with arms raised holding heavy dry walls in place, whereas form work is notable for extensive lumbar flexion and had the two highest rates of work related musculoskeletal disorders. The psychosocial element of job control was associated with both upper and lower extremity disorders. These union carpenters, who were relatively young, already were experiencing considerable work related physical problems. CONCLUSION: This study supports the need for vigilant ergonomic intervention at job sites and early ergonomic education as an integral part of apprenticeship school training to ensure that carpenters remain fit and healthy throughout their working lifetime.     

Malignant lymphomas and leukemias,and exposures in the wood industry: an industry-based case-referent study

Summary Jobs and exposures in woodwork may entail an elevated risk of lymphomas and leukemias. Exposures occurring in woodwork were scrutinized in a small industry-based case-referent study of four cases of Hodgkin's disease, eight cases of non-Hodgkin's lymphoma, 12 cases of leukemia, and 152 matched referents, all from the Finnish wood industry. Past exposures to wood dust, chlorophenols, terpenes, and engine exhaust, individually reconstructed through plant- and period-specific job exposure matrices, were unrelated to lymphoma/leukemia risk. Exposures to various solvents were associated with an odds ratio (OR) of 5.6 (95% confidence interval 1.0–32.0). The OR for formaldehyde was 2.5 (nonsignificant). The results are interpreted as providing limited evidence of the role of exposure to some as yet unidentified organic solvents in increasing the risk of malignant lymphomas. Formaldehyde may be another woodwork-related risk factor for some lymphomas, but the power of the study was too low for empirical confirmation of this possibility. Leukemias did not seem to be associated with any of the exposures studied.