A survey of airborne and skin exposures to chemicals in footwear and equipment factories in Thailand

This research reports on a pilot industrial hygiene study that was performed at four footwear factories and two equipment factories in Thailand. Workers in these factories were exposed through inhalation and dermal contact to a large number of organic vapors from solvents and cements that were hand applied. In addition, these workers were exposed to highly toxic isocyanates primarily through the dermal route. A total of 286 personal air samples were obtained at the four footwear factories using organic vapor monitors; individual job tasks were monitored using a real-time MIRAN Spectrometer. A total of 64 surface, tool, or hand samples were monitored for isocyanates using surface contamination detectors. Real-time measurements were also obtained for organic vapors in two equipment factories. From 8% to 21% of the workers sampled in each footwear factory were overexposed to mixtures of chemicals from solvents and cements. Up to 100% of the workers performing specific job tasks were overexposed to mixtures of chemicals. From 39% to 69% of the surface samples were positive for unreacted isocyanates. Many of the real-time measurements obtained in the equipment factories exceeded occupational exposure limits. Personal protective equipment and engineering controls were inadequate in all of the factories.     

Prenarcotic and neuraesthenic symptoms among Dutch workers exposed to organic solvents

A population of 379 Dutch workers exposed to organic solvents was compared with a non-exposed population of 443 workers with regard to the prevalence of prenarcotic and neuraesthenic symptoms. Participants completed a questionnaire to collect information about their occupational history, exposure to organic solvents, and the occurrence of symptoms. The results of the study indicated that workers exposed to solvents have a higher reporting rate of prenarcotic symptoms than workers not exposed to solvents. The prevalence of chronic neurotoxic effects, however, in the form of neuraesthenic symptoms was only weakly associated with reported exposure to organic solvents. The influence of work stress in the development of these symptoms is perhaps more important than the role of exposure to organic solvents. It is concluded that the organic solvent syndrome type I, as defined by an international workshop, is not an important health hazard among Dutch painters.     

Prenarcotic and neuraesthenic symptoms among Dutch workers exposed to organic solvents.

A population of 379 Dutch workers exposed to organic solvents was compared with a non-exposed population of 443 workers with regard to the prevalence of prenarcotic and neuraesthenic symptoms. Participants completed a questionnaire to collect information about their occupational history, exposure to organic solvents, and the occurrence of symptoms. The results of the study indicated that workers exposed to solvents have a higher reporting rate of prenarcotic symptoms than workers not exposed to solvents. The prevalence of chronic neurotoxic effects, however, in the form of neuraesthenic symptoms was only weakly associated with reported exposure to organic solvents. The influence of work stress in the development of these symptoms is perhaps more important than the role of exposure to organic solvents. It is concluded that the organic solvent syndrome type I, as defined by an international workshop, is not an important health hazard among Dutch painters.     

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

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

Solvent pollution in shoe factories]

In order to study solvent exposure in shoe factories, 43 kinds of glues and 22 solvent products used in footwear manufacturing were analyzed. A gas chromatographic spectrometric method was used to identify the mixtures of solvents contained in glues and their diluents. Acetone, ethylacetate and cyclohexane were the solvents more frequently found in glues. Cyclohexane represented on average about 40% of the solvent mixture. Methyl ethyl ketone, 3-methylpentane and 2-methylpentane were often present in glues (45-52% of the samples), but only in a few cases were they associated with n-hexane. N-hexane and methylcyclopentane were found in 32% of the glue samples. N-hexane represented 47% of the solvents only in one glue. Most of the glues contained less than 10% n-hexane. Other solvents (dichloropropane, toluene, trichloroethane, butyl acetate, iso-butyl acetate and 2,2-dimethylbutane) were found in few glue samples or in low percentages. The 22 solvents used as glue diluents were mainly acetone, ethylacetate, dichloromethane and methyl ethyl ketone. The results suggest that solvent exposure in shoe factories has changed compared with data reported about 10 years ago. Biological monitoring of shoe factory workers should measure exposures to the specific solvents found in each factory, especially acetone, cyclohexane, ethylacetate and methyl ethyl ketone.     

Knowledge, attitude and practice regarding organic solvents among printing workers in Hong Kong

To find out the prevalence of good knowledge, appropriate attitude and safe practice among printing workers exposed to organic solvents in Hong Kong, and to see if safe practice was influenced by the knowledge of and the attitude towards the harmful effects of organic solvents as well as other factors. The survey was conducted in a sample of 501 male printing workers from 28 factories in Hong Kong. The knowledge of and attitude towards the harmful effects of organic solvents, as well as the good practices adopted by the workers when handling solvents were explored using a questionnaire. Multiple logistic regression analysis was conducted to identify the major factors that influenced the knowledge, attitude and practice of workers. The prevalence of good knowledge, appropriate attitude and safe practice was low, being 20.4%, 38.4% and 22.0% respectively. Good knowledge was positively associated with awareness of the relevant legislation and past drinking behavior and negatively associated with current smoking. Appropriate attitude depended on having good knowledge and younger age. Safe practice did not depend on knowledge and attitude, but was positively associated with being informed of safety precautions and being supplied with chemical information by supervisors. The majority of workers believed that their employers, the Government and other statutory bodies should be responsible for providing information on chemicals, but very few of them actually obtained information from these sources. More workers preferred publications and talks rather than television as the means of obtaining further knowledge on chemicals. Front line supervisors have a pivotal role to play in improving safe practices of workers by informing them of the necessary precautions and supplying the relevant chemical information.     

Spontaneous abortions among dental assistants, factory workers, painters, and gardening workers: a follow up study.

This investigation was conducted to test the hypothesis that exposure of pregnant women to chemicals increases the risk of spontaneous abortion. The chemical risk factors under study to which dental assistants, factory workers, painters, and gardening workers were exposed were nitrous oxide, inorganic mercury, organic solvents, and pesticides. The study was carried out within the Danish county of Funen. It included all dental assistants employed in private or public dentistry. A comparable reference group was made up by employees less exposed to chemicals. Further study groups included all women painters within the county, women factory workers from selected factories, and about 50% of the women gardening workers within the county. Shop assistants and packers formed their control group. Information was obtained through a postal questionnaire study in May 1980 and from hospital records. Only among factory workers and painters was the odds ratio of spontaneous abortion found to be significantly increased. Neither among these women nor among dental assistants and gardening workers, however, was the reported exposure to any single chemical during pregnancy associated with a significantly increased odds ratio of spontaneous abortion.     

Solvent Exposures at Shoe Factories and Workshops in Hebron City,West Bank

Abstract

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

Prevalence of upper extremity symptoms and possible risk factors in workers handling paper currency

The prevalence of upper extremity symptoms in the workforceis high, particularly in industries characterized by forceful,repetitive or awkward movements. A study was undertaken to assessthe prevalence of upper extremity symptoms in bank workers ina paper currency processing operation and to examine the roleof possible risk factors for these complaints. Thirty-nine workersof a total workforce of 47 were assessed with a questionnaireand physical examination. The questionnaire collected informationabout demographics, health status, symptom reporting, psychosocialwork stressors and other work exposure characteristics. Overall,59% of the workers reported having significant work-relatedupper extremity musculoskeletal symptoms in the preceding year,including 49% with neck and shoulder symptoms and 49% with armand wrist symptoms. In this study the key predictive factorfor upper extremity musculoskeletal symptoms was psychologicaljob demands. The workers had similar ergonomic stressors (withlittle gradient of exposure) and therefore our results do notcontradict the importance of ergonomic factors in the developmentof upper extremity symptoms. However, the results do suggestthat within a group exposed to similar ergonomic stressors,psychological job demands may be an important factor associatedwith musculoskeletal symptoms.     

An outbreak of N-hexane induced polyneuropathy among press proofing workers in Taipei

The objective of this study was to determine the prevalence and the etiology of polyneuropathy observed among press proofing workers in Taipei. Neurological examinations of 59 workers, from 16 press proofing factories, were conducted. Fifty-four of those workers subsequently underwent studies of nerve conduction velocities. Samples of bulk solvent from the involved factories were analyzed for their contents using gas chromatography. Fifteen (25%) of the study group were found to have polyneuropathy. All 15 patients with polyneuropathy were from factories in which solvents containing n-hexane were regularly used, and there was a significant association between n-hexane concentration in the bulk samples and prevalence of polyneuropathy. The air concentration of n-hexane in one factory in which all six employees developed polyneuropathy was 190 ppm. Workers who were exposed to n-hexane at air levels of less than 100 ppm but who frequently worked overtime showed a significant slowing of motor nerve conduction velocities on median, ulnar, and peroneal nerves. Of 13 workers who regularly slept in the factory, 12 (92%) had polyneuropathy compared to three (7%) of 46 workers who did not sleep in the factory. The outbreak of polyneuropathy was attributed to a combination of the use of solvents with high contents of n-hexane, poor ventilation, and the practice of sleeping in the factories between shifts.     

A cross-sectional study of musculoskeletal symptoms and risk factors in semiconductor workers

As part of the cross-sectional component of the Semiconductor Health Study, we assessed prevalence of specific musculoskeletal symptoms and their association with possible ergonomic risk factors. A total of 3,175 persons (78% participation rate) from eight manufacturing sites across the U.S. completed a health and work questionnaire. Using logistic regression methods to adjust for nonoccupational factors, we compared musculoskeletal symptom (self report) prevalence among fabrication room (fab) and nonfab workers, among specific work process groups, and among workers exposed to selected ergonomic stressors. Overall, seven of 12 musculoskeletal outcomes were significantly more prevalent among fab workers. Distal upper-extremity symptoms were more common among fab than nonfab workers [relative risk (RR) = 1.44, 95% confidence interval (CI) = 1.26-1.63] and showed a dose-response effect with hours per day spent in the fab; increased risk was associated with frequency of lifting and with use of vacuum wands and projection aligners. female sex and high somatization index score were associated with increased reporting for all musculoskeletal outcomes.     

Spontaneous abortions among women working in the pharmaceutical industry.

A register based study was conducted on the pregnancy outcome of female workers in eight Finnish pharmaceutical factories to determine whether they had a higher risk of spontaneous abortion than the general population or matched controls. Information about all female workers who had been employed in the factories during the years 1973 or 1975 (four factories) to 1980 was obtained from the employers. The workers' pregnancy data were collected from the nation wide hospital discharge register and polyclinic data of hospitals from 1973 to 1981. The total number of 1795 pregnancies included 1179 deliveries, 142 spontaneous abortions, and 474 induced abortions. The spontaneous abortion rate (the number of spontaneous abortions X 100, divided by the number of spontaneous abortions plus the number of births) during employment was 10.9% and before/after employment 10.6%. The rate for all the women in the corresponding central hospital districts was 11.3% [corrected] during the study period. A case-control study was also carried out in which the cases were 44 women who had a spontaneous abortion during employment in the pharmaceutical factory. Three age matched female pharmaceutical factory workers who had given birth to a child were chosen as controls for every case. The information about occupational exposures was collected from questionnaires completed by the occupational physician or nurse at the factory. The response rate was 93%. Exposure to chemicals was more common among the cases than among the controls. For methylene chloride, a solvent commonly used in the pharmaceutical industry, the increase in odds ratio of borderline significance (odds ratio 2.3, p = 0.06). In a logistic regression model (which included oestrogen exposure, solvent exposure frequency of the usage, and heavy lifting) the odds ratio was increased for oestrogens (odds ratio 4.2, p = 0.05) and for continuous heavy lifting (odds ratio 5.7, p = 0.02). The odds ratio for spontaneous abortions was greater among those exposed to four or more solvents (odds ratio 3.5, p=0.05) than among those exposed to one to three solvents (odds ration 0.8, p=0.74).     

Acute health effects common during graffiti removal

Objective: The aim of this study was to identify possible health effects caused by different cleaning agents used in graffiti removal. Methods: In 38 graffiti removers working 8-h shifts in the Stockholm underground system, the exposure to organic solvents was assessed by active air sampling, biological monitoring, and by interviews and a questionnaire. Health effects were registered, by physical examinations, porta7ble spirometers and self-administered questionnaires. The prevalence of symptoms was compared with 49 controls working at the underground depots, and with 177 population controls. Results: The 8-h time-weighted average exposures (TWA) were low, below 20% of the Swedish permissible exposure limit value (PEL) for all solvents. The short-term exposures occasionally exceeded the Swedish short-term exposure limit values (STEL), especially during work in poorly ventilated spaces, e.g. in elevators. The graffiti removers reported significantly higher prevalence of tiredness and upper airway symptoms compared with the depot controls, and significantly more tiredness, headaches and symptoms affecting airways, eyes and skin than the population controls. Among the graffiti removers, some of the symptoms increased during the working day. On a group basis, the lung function registrations showed normal values. However, seven workers displayed a clear reduction of peak expiratory flow (PEF) over the working shift. Conclusions: Though their average exposure to organic solvents was low, the graffiti removers reported significantly higher prevalence of unspecific symptoms such as fatigue and headache as well as irritative symptoms from the eyes and respiratory tract, compared with the controls. To prevent adverse health effects it is important to inform the workers about the health risks, and to restrict use of the most hazardous chemicals. Furthermore, it is important to develop good working practices and to encourage the use of personal protective equipment. Received: 23 June 2000 / Accepted: 01 November 2000     

Spontaneous abortions among women working in the pharmaceutical industry

A register based study was conducted on the pregnancy outcome of female workers in eight Finnish pharmaceutical factories to determine whether they had a higher risk of spontaneous abortion than the general population or matched controls. Information about all female workers who had been employed in the factories during the years 1973 or 1975 (four factories) to 1980 was obtained from the employers. The workers' pregnancy data were collected from the nation wide hospital discharge register and polyclinic data of hospitals from 1973 to 1981. The total number of 1795 pregnancies included 1179 deliveries, 142 spontaneous abortions, and 474 induced abortions. The spontaneous abortion rate (the number of spontaneous abortions X 100, divided by the number of spontaneous abortions plus the number of births) during employment was 10.9% and before/after employment 10.6%. The rate for all the women in the corresponding central hospital districts was 11.3% [corrected] during the study period. A case-control study was also carried out in which the cases were 44 women who had a spontaneous abortion during employment in the pharmaceutical factory. Three age matched female pharmaceutical factory workers who had given birth to a child were chosen as controls for every case. The information about occupational exposures was collected from questionnaires completed by the occupational physician or nurse at the factory. The response rate was 93%. Exposure to chemicals was more common among the cases than among the controls. For methylene chloride, a solvent commonly used in the pharmaceutical industry, the increase in odds ratio of borderline significance (odds ratio 2.3, p = 0.06). In a logistic regression model (which included oestrogen exposure, solvent exposure frequency of the usage, and heavy lifting) the odds ratio was increased for oestrogens (odds ratio 4.2, p = 0.05) and for continuous heavy lifting (odds ratio 5.7, p = 0.02). The odds ratio for spontaneous abortions was greater among those exposed to four or more solvents (odds ratio 3.5, p=0.05) than among those exposed to one to three solvents (odds ration 0.8, p=0.74).     

Musculoskeletal disorders in industrial workers of Delhi

To study the musculoskeletal disorders in industrial workers in Delhi, 631 workers from 60 factories representing small and medium-sized enterprises located in Delhi were interviewed. Many (59.4%) of the workers had musculoskeletal disorders. Tailors, those working near furnaces, cooks, workers in buffing, checking and assembly work, and those working with chemicals had the most joint complaints. Cervical pain was more frequent in tailoring and packing work, whereas lumbar pain was more common in buffing, operators working on presses, those using hand and power tools, and those lifting heavy manual loads. Contract workers had less musculoskeletal morbidity than regular and temporary workers. Skilled workers also had less morbidity. Workers experiencing more job satisfaction reported fewer musculoskeletal disorders. The high prevalence of musculoskeletal disorders in workers needs urgent attention from the health and labor sectors. An ergonomic approach to prevention should be considered. The current manual load handling limits prescribed in the Indian Factory Rules potentially expose workers to back stress. It is also inappropriate to have separate load-lifting limits for men and women. Research is urgently required to determine the safe load handling limits for the Indian working population based on ergonomic principles. Until internationally acceptable safe limits are established, back pain should be a notifiable disease in India.     

Exposure to acid anhydrides in three resin and one cushioned flooring manufacturing plants

Acid anhydrides are reactive organic chemicals of low molecular weight which cause occupational asthma. No previous research on the relationship between exposure to these chemicals and respiratory sensitization and development of occupational asthma has been reported. A retrospective cohort study was carried out in four factories (three alkyd resin factories and one cushioned flooring factory) to investigate the nature of exposure-response relationships for sensitization to phthalic anhydride (PA), trimellitic anhydride (TMA) and maleic anhydride (MA). This paper describes the results of full-shift and task-specific exposure measurements. Exposure to PA was low in relation to the Occupational Exposure Standard (OES). The highest full-shift PA exposures occurred among resin operators in the resin factory that used solid PA as compared to other resin factories where liquid PA was used. Arithmetic mean exposure levels to TMA and MA in the resin factories were well below their respective OESs. Short-term high exposures occurred during loading of acid anhydrides into the reactors and sampling and testing of the resin. Relatively high full-shift exposure to TMA occurred in the cushioned flooring factory, although no high peak exposures were detected.     

Sister chromatid exchanges and micronuclei in peripheral lymphocytes of shoe factory workers exposed to solvents

We examined sister chromatid exchanges (SCEs) and micronuclei (MN; cytokinesis-block method) in cultured peripheral lymphocytes from 52 female workers of two shoe factories and from 36 unexposed age- and sex-matched referents. The factory workers showed an elevated level of urinary hippuric acid, a biomarker of toluene exposure, and workplace air contained high concentrations of various organic solvents such as toluene, gasoline, acetone, and (in one of the plants only) ethylacetate and methylenediphenyl diisocyanate. The shoe factory workers showed a statistically significant higher frequency of micronucleated binucleate lymphocytes in comparison with the referents. This finding agreed with three preliminary MN determinations (each comprising 27-32 shoe workers and 16-20 controls) performed in one of the plants 2-5 years earlier. The shoe factory workers also had a lower average level of blood hemoglobin than the referents. In contrast, no difference was found between the groups in SCE analysis. Smokers showed significantly higher mean frequencies of SCEs per cell and high frequency cells (HFC) than nonsmokers. Aging was associated with increased MN rates and reduced cell proliferation. Polymorphism of the glutathione S-transferase M1 gene (GSTM1) did not affect the individual level of SCEs; but in smoking shoe workers an effect of the occupational exposure on the frequency of micronucleated cells could be seen only in GSTM1 null subjects. The low prevalence of the glutathione S-transferase T1 (GSTT1) null genotype precluded the evaluation of the influence of GSTT1 polymorphism. Our results show that the shoe factory workers have experienced genotoxic exposure, which is manifest as an increase in the frequency of MN, but not of SCEs, in peripheral lymphocytes. The exposures responsible for the MN induction could not be identified with certainty, but exposure to benzene in gasoline and methylenediphenyl diisocyanate may explain some of the findings.     

Developing an action-based health and safety training project in southern China

A project brought together international footwear manufacturers, labor rights groups, local contract factories, and occupational health professionals to strengthen factory health and safety programs in southern China. Steps involved in the two-year project, including needs assessment, interviews and focus groups with workers and supervisors; design and development of a participatory workshop; development of plant-wide health and safety committees in three footwear factories; and evaluation project impact, are discussed. The project significantly increased occupational safety and health knowledge, and hazards in the factories were identified and corrected. Successes and challenges faced by three functioning worker-management health and safety committees are discussed. Key elements to create effective programs with meaningful participation by workers include: 1) developing clear guidelines that enable multi-stakeholder groups to collaborate; 2) obtaining top-level management support; 3) building workers' knowledge and capacity to fully participate; 4) involving local labor rights groups and occupational professionals in support and technical assistance; and 5) connecting project goals to larger issues within a country and the global economy.     

Musculoskeletal problems among workers of an Iranian rubber factory

Musculoskeletal disorders (MSDs) are a common health problem throughout the world and a major cause of disability among the work force. Assessment of exposure level to MSD risk factors can be an appropriate base for planning and implementing interventional ergonomic programs in the workplace. This study was conducted among workers of an Iranian rubber factory with the objectives of (a) determination of the prevalence of MSDs among production line workers, and (b) assessment of the level of exposure to MSD risks. In this study, all 16 production units of the factory were studied. In each unit, 50% of the workers were randomly selected and included in the study. A total of 454 workers participated. The Nordic Musculoskeletal Questionnaire was used to study the prevalence of MSDs and the Quick Exposure Check (QEC) technique was applied to assess physical exposure to the risks. The videotaping technique was used to collect the required data for each worker. The vast majority of the workers (73.6%) had suffered from some kind of musculoskeletal symptoms during the last 12 months. The highest prevalence was reported in the lower back (50.2%), knees (48.5%) and upper back (38.1%). In 85.5% of the workers studied, the QEC score was high or very high. Statistical analysis showed a significant association between the QEC level of risk and MSDs symptoms (p<0.001). The most common ergonomics problems were found to be awkward postures and manual material handling. MSDs had occurred with a high rate among workers of this rubber factory. Corrective measures for reducing risk level seemed essential. Elimination of awkward postures and manual material handling in the workplace were recommended.     

Respiratory illness in agricultural workers

Respiratory diseases have long been recognized in association with work in farming. Overall, only a small proportion of the population is employed in agriculture, so respiratory disease in farmers is not a major public health issue. However, farmers are known to have high morbidity and mortality from certain respiratory diseases, as shown by routinely collected statistics. Despite this, knowledge of the frequency, nature and risk factors for some respiratory disorders in agricultural workers is incomplete. Multiple exposures are common and some exposures can give rise to more than one specific disease. Moreover, the most common respiratory symptoms reported by farm workers (wheeze, dyspnoea and cough) are relatively non-specific and can be associated with several occupational respiratory disorders. This review describes the main occupational respiratory illnesses in farming and summarizes the current literature about epidemiology and prevention. The most important diseases are rhinitis and asthma, which, although common, are not usually fatal. Some non-allergic conditions, e.g. asthma-like syndrome and organic toxic dust syndrome, are not yet fully understood, but appear to be common among farm workers. The most serious respiratory diseases are hypersensitivity pneumonitis and respiratory infections, but these are rare. Most importantly, respiratory diseases are preventable by controlling harmful exposures to organic dust, toxic gases and chemicals on farms through improvements in animal rearing techniques, ventilation of animal accommodation, careful drying and storage of animal feed-stuffs, crops and other products, and use of personal protective equipment.