Plasma cholinesterase level of Ethiopian farm workers exposed to chemical pesticide

BACKGROUND: Pesticide applications can have unwanted health consequences. AIM: To study cholinesterase levels in farm workers with varying exposure to chemical pesticide. METHODS: Plasma cholinesterase (PChE) was measured in workers at two Ethiopian farms. A standard questionnaire adopted from the British Medical Research Council was used to determine the health status of the subjects. RESULTS: A total of 82 farm workers and 47 controls participated in the study. While the mean values of plasma cholinesterase were generally lower in those exposed, this difference was only significant in the sprayers at Birr farm (P<0.05). In this group, four sprayers had cholinesterase activity lower than 50%. CONCLUSION: The sprayers in both farms were the most affected groups, suggesting that improved controls on workplace exposure to pesticide is required in these groups of workers.     

Respiratory symptoms in fish processing workers on the Adriatic coast of Croatia

This article describes respiratory symptoms and lung function in 98 fish processing female workers employed in a fish processing plant located on the Croatian Adriatic coast and 95 matching controls. The study included chronic and acute respiratory symptoms which developed during the shifts. Lung function measurements included forced vital capacity (FVC), one-second forced expiratory volume (FEV(1)) and maximal expiratory rates at 50 % and the last 25 % (FEF(50), FEF(25)). Chronic respiratory symptoms were significantly dominant in fish processing workers compared to controls. The most common chronic symptoms were hoarseness (57.1 %), nasal catarrh (51.0 %), chronic cough (42.9 %), chronic phlegm (34.7 %), and frequent chest cold (35.7 %). Exposed smokers and nonsmokers had a similar prevalence of chronic respiratory symptoms. Acute symptoms over the work shift were high, with headache in lead (smokers: 62.5 %; nonsmokers: 56.1 %). Most of the ventilatory capacity parameters were significantly lower than predicted, FEF(25) in particular, indicating obstructive changes predominantly in the smaller airways. These findings suggest that fish processing workers are prone to developing acute and chronic respiratory symptoms as well as to lung function changes. This calls for medical and technical preventive measures to be introduced in the work environment of the fish processing plant.     

Assessment of Occupational Symptoms and Chemical Exposures for Nail Salon Technicians in Daegu City,Korea

Objectives

This study aimed to evaluate occupational symptoms and chemical exposures of nail salon technicians.

Methods

Work-related symptoms of nail salon technicians in Daegu City were surveyed using a researcher-administered questionnaire, and responses were compared to those of non-exposed office workers as controls. Personal exposure level of airborne volatile organic compounds was also monitored using passive samplers.

Results

A total of 159 subjects in 120 salons were interviewed. Average work-shift concentrations of 13 chemicals were measured for 50 workers from 30 salons using personal passive samplers. The most frequently reported respiratory or neurologic symptoms by nail shop technicians compared to controls were nose irritation (odds ratio [OR], 54.0; confidence interval [CI], 21.6 to 134.8), followed by headache (OR, 9.3; CI, 4.7 to 18), and throat irritation (OR, 4.3; CI, 2.2 to 8.5). For eyes and skin, 92% of respondents complained eye irritation (OR, 13.1; CI, 5.7 to 30.1). In musculoskeletal symptoms, workers reported pain or discomfort in shoulders (OR, 20.3; CI, 7.7 to 54) and neck (OR, 19.7; CI, 8.9 to 43.6). From personal measurements, the proportion of exceeding the Korean Occupational Exposure Limit was the highest for acetone with 64%, followed by toluene (50%), butyl acetate (46%), and methyl methacrylate (12%). However, the service was being provided without a proper ventilation system in most surveyed shops.

Conclusions

Based on these findings, it is warranted to have appropriate local exhaust ventilation place to ensure adequate health protection of nail shop technicians as well as customers. At the same time, greater policy interests are warranted in nail care business to protect health of both workers and customers.     

Lung function and clinical findings in a cross-sectional study of arc welders

Summary An epidemiological, cross-sectional study was conducted in order to assess non-neoplasic effects on the lung due to chronic exposure to arc welding fumes and gases. The study involved 346 arc welders and 214 control workers from a factory producing industrial vehicles. These workers (welders and controls) had never been exposed to asbestos. Respiratory impairments were evaluated by using a standardized questionnaire, a clinical examination, chest radiophotography and several lung function tests (spirometry, bronchial challenge test to acetylcholine, CO transfer tests according to the breath-holding and the steady-state methods, N₂ washout test). The only significant differences between the welders overall compared to the controls were a slightly higher bronchial hyper-reactivity to acetylcholine and a lower lung diffusing capacity for CO in the welders. However, non-specific, radiologic abnormalities (reticulation, micronodulation) and obstructive signs were more frequent in the most exposed welders (welding inside tanks) than in welders working in well ventilated workplaces. The nature of the metal welded (mild-steel, stainless steel, aluminium) did not seem to have an influence on respiratory impairments. In the mild-steel welders, respiratory symptoms (dyspnoea, recurrent bronchitis) and obstructive signs were more frequent in the welders using a manual process than in the welders involved with the semi-automatic process (MIG). For all the workers (welders and controls), smoking had a markedly adverse effect on respiratory symptoms and lung function. Moreover, smoking seemed to interact with welding since CO lung transfer was more impaired in smoking welders than in smoking controls.     

Health effects and personal protection in pest control workers using organophosphorus insecticides]

One hundred and sixteen pest control workers (16 termite control workers (Sprayer I), 46 cockroach or fly-control workers (Sprayer II) and 56 both termite and cockroach or fly-control workers (Sprayer III)) were surveyed by a questionnaire and health examinations. Variety and quantity of pesticide used, personal usage of protective devices (respirator, gloves, work clothes, under wear), and conditions related to bathing were studied by a questionnaire. Relationships between protective devices and blood cholinesterase activity (ChE) were also analyzed. Significant findings were as follows: Most of the pest control operators wore gum gloves and gas masks when involved in termite control. However in the case of cockroach or fly-control, 38% did not wear gloves, and for respiratory protection 44% wore gas masks while 25% of them did not even use any form of respirators. In spite of having better protective practices than sprayers II and III, sprayer I showed significantly lower plasma ChE activity than both sprayer II and III. Plasma ChE activity in sprayers who put on simple respirators tended to be lower than those using gas masks. Plasma ChE activity was also significantly lower in those workers who had less frequent changes of work clothes compared to those with more frequent.     

Respiratory symptoms, lung function, and pneumoconiosis among self employed dental technicians.

From the registry of self employed workers living in Paris, a group of 105 dental technicians was studied to evaluate occupational exposure, to determine respiratory manifestations, and to investigate immune disturbances. Seventy one dental technicians (age range 43-68: group D), 34 dental technicians younger than 43 or older than 68 (group d), and 68 control workers (age range 43-66: group C) were investigated. The demographic characteristics and the smoking habits of the groups D and C did not differ significantly. The dental technicians often worked alone (43.7%) or in small laboratories without adequate dust control. The mean duration of their exposure was long (group D 34.0 (SD 8.4) years). The prevalence of respiratory symptoms did not differ between groups D and C except for the occurrence of increased cough and phlegm lasting for three weeks or more over the past three years (group D 16.9%, group C 2.9%, p < 0.007). The effect of cigarette smoking on respiratory symptoms and lung function was obvious. All mean values of lung function for dental technicians and controls were within normal limits. Significant decreases in all mean lung function values were found among smokers by comparison with non-smokers, however, and a positive interaction with occupational exposure was established. The x ray films of dental technicians (n = 102, groups D and d) were read independently by four readers and recorded according to the International Labour Office classification of pneumoconioses. The prevalence of small opacities greater than 1/0 was 11.8% with a significant increase with duration of exposure. The prevalence among dental technicians with 30 years or exposure or more was significantly higher (22.2%) than those with less than 30 years (3.5, p < 0.004). The prevalence of autoantibodies (rheumatoid factors, antinuclear antibodies, and antihistone antibodies) was not significantly different in the groups D and C. When positive, autoantibodies only occurred at low concentrations. This finding contrasts with previous reports on the occurrence of autoantibodies and even of connective tissue diseases in dental technicians. In conclusion, the study confirms an increased risk of pneumoconiosis among dental technicians. Moreover, there may be other lung disorders such as impairment of lung function especially in association with cigarette smoking.     

Level of silica in the respirable dust inhaled by dental technicians with demonstration of respirable symptoms

Dental technicians are exposed to various dusts in working laboratories. This study was conducted to measure level of silica in the respirable dust generated from dental fixed prosthodontics manufacturing processes using Fourier Transform Infrared Spectroscopy (FTIR), and to compare their occurrence of respiratory symptoms with that of non-dental hospital workers (control group). Respirable dusts were personally sampled from dental technicians working at dental laboratories in Seoul Korea according to NIOSH Method 0600. Fifty personal samples were obtained during porcelain or polishing process and weighed by a gravimetric method. Concentration of respirable dust was 651 +/- 548 microg/m3 (Mean +/- SD) with highest concentration of 2,874 microg/m3 during the porcelain process and 725 +/- 414 microg/m3 with highest concentration of 1,764 microg/m3 during the polishing process. Concentration of silica was 6.51 +/- 6.07 microg/m3 with 18.85 microg/m3 highest and 14.88 +/- 11.21 microg/m3 with 50.98 microg/m3 highest for the porcelain and polishing process, respectively. Level of silica contents in the dust was 0.81% and 1.66% for the porcelain and polishing process, respectively. The level of silica contents and silica concentration were significantly different between the two processes. Comparing prevalence of respiratory symptoms between non-smoking seventeen dental technicians and thirty-five control workers, wheezing and rhinorrhea were significantly more manifested in the dental technicians than the controls. Total frequency of respiratory symptoms was also significantly higher in the dental technicians than the controls.     

Respiratory Protection Behavior and Respiratory Indices among Poultry House Workers on Small,Family-Owned Farms in North Carolina: A Pilot Project

The aim of this pilot study was to evaluate respiratory behavior and respiratory indices of poultry workers on family-owned, poultry farms with 10 or less employees in North Carolina. A field study was conducted to collect data on participants (N = 24) using spirometry, fractional exhaled nitric oxide (Feno), and an interviewer-administered questionnaire. The majority of workers (76%) ranked respiratory protection as being important, yet 48% reported never or rarely wearing respiratory protection when working in dusty conditions. A large percent of workers reported eye (55%) and nasal (50%) irritation and dry cough (50%). On average, pulmonary lung function and Feno tests were normal among nonsmokers. In bivariate analysis, significant associations were identified between working 7 days on the farm (P = .01), with eye irritation, and working 5 or fewer years in poultry farming (P = .01). Poultry workers on family-owned farms spend a considerable amount of work time in poultry houses and report acute respiratory-related health symptoms. Administrative controls among small, family-owned poultry farms are necessary to improve and promote safety and health to its employees.     

Neuropsychological Effects of Long-Term Low-Level Organophosphate Exposure in Orchard Sprayers in England

The health effects from prolonged low-level organophosphate exposure are unknown. We hypothesized that exposed individuals would show neuropsychological decrements when compared with unexposed individuals, and that cumulative organophosphate exposure would be correlated with neuropsychological performance. We used a quasiexperimental cross-sectional design to compare neuropsychological test scores among three groups: orchard sprayers exposed to organophosphates, and construction worker and pig farm workers who were not exposed. Relative to construction workers, orchard sprayers were significantly slower on negative statements of the syntactic reasoning test. However, we found no relationship between cumulative exposure and test response. The slower response of the orchard sprayers was apparently exposure-related, but we could not identify an underlying neurotoxic mechanism. Therefore, we are unable to conclude whether this is a specific cognitive effect, or a decrement arising on the most sensitive test employed.     

Neuropsychological effects of long-term low-level organophosphate exposure in orchard sprayers in England

The health effects from prolonged low-level organophosphate exposure are unknown. We hypothesized that exposed individuals would show neuropsychological decrements when compared with unexposed individuals, and that cumulative organophosphate exposure would be correlated with neuropsychological performance. We used a quasiexperimental cross-sectional design to compare neuropsychological test scores among three groups: orchard sprayers exposed to organophosphates, and construction worker and pig farm workers who were not exposed. Relative to construction workers, orchard sprayers were significantly slower on negative statements of the syntactic reasoning test. However, we found no relationship between cumulative exposure and test response. The slower response of the orchard sprayers was apparently exposure-related, but we could not identify an underlying neurotoxic mechanism. Therefore, we are unable to conclude whether this is a specific cognitive effect, or a decrement arising on the most sensitive test employed.     

Respiratory and general health impairments of workers employed in a municipal solid waste disposal at an open landfill site in Delhi

The objective of this study was to examine the respiratory and general health of workers employed in a municipal solid waste (MSW) disposal at an open landfill site in India. Ninety-six landfill workers of Okhla landfill site, Delhi, and 90 controls matched for age, sex, and socioeconomic conditions were enrolled. Health data was obtained from questionnaire surveys, clinical examination and laboratory investigations. Lung function was evaluated by spirometry. Compared with matched controls, landfill workers had significantly higher prevalences of both upper and lower respiratory symptoms, and they suffered more often from diarrhea, fungal infection and ulceration of the skin, burning sensation in the extremities, tingling or numbness, transient loss of memory, and depression. Spirometry revealed impairment of lung function in 62% of the landfill workers compared to 27% of the controls. Sputum cytology showed squamous metaplasia, abundance of inflammatory cells, alveolar macrophages (AM) and siderophages (macrophages with iron deposits), and high elastase enzyme activity in neutrophils and AM of a majority of landfill workers, indicating adverse cellular lung reaction. Hematological profiles of these workers depicted low hemoglobin and erythrocyte levels with high total leukocyte, eosinophil and monocyte counts. Erythrocytes with target cell morphology were abundant in 42% of the landfill workers compared to 10% of the controls. Toxic granulation in neutrophils, an indication of infection and inflammation, was recorded in 94% of the landfill workers and in 49% of the controls. The results demonstrated higher prevalence of respiratory symptoms, inflammation of the airways, lung function decrement and a wide range of general health problems in MSW disposal workers.     

Outbreak of hypersensitivity pneumonitis among mushroom farm workers.

Between April 1982 and August 1985, seven cases of mushroom worker's lung (MWL), a form of hypersensitivity pneumonitis, were diagnosed among workers at one mushroom farm in Florida. The cases suffered from episodic shortness of breath, cough, fever and chills, myalgia, malaise, and difficulty breathing. Pulmonary function testing revealed restrictive ventilatory impairment and reduced diffusing capacity; chest radiographs exhibited diffuse interstitial pulmonary infiltrates. The seven cases occurred among workers from different farm operations, suggesting that workers throughout the farm were exposed to the disease causing agent(s). Six of the affected workers left employment at the farm in order to remain free of symptoms. The other affected worker was able to continue working at the farm, but only by remaining in a maintenance shop which was physically separated from the rest of the farm facilities. An industrial hygiene survey demonstrated that farm workers from every work area were exposed to organic dust constituents suspected of causing MWL, but no specific antigens were identified as the cause of the cases. Of the remaining workers who participated in a cross-sectional respiratory morbidity survey at the farm, approximately 20% of the more heavily exposed workers reported occasionally experiencing symptoms consistent with MWL. Approximately 10% of the workers had below normal spirometry test results, but interpretation was hampered by the diverse racial makeup of the population and lack of an adequate comparison group. No abnormalities consistent with either acute or chronic MWL were seen on the chest radiographs. Serologic tests demonstrated that almost all workers had been exposed to antigens capable of causing MWL, but the results were not associated with health status. At the time of the cross-sectional survey, no workers were found to be suffering acute respiratory problems consistent with MWL.     

Acute respiratory symptoms in workers exposed to vanadium-rich fuel-oil ash

BACKGROUND: Occupational exposure to fuel-oil ash, with its high vanadium content, may cause respiratory illness. It is unclear, however, what early acute health effects may occur on the pathway from normal to compromised respiratory function. METHODS: Using a repeated measures design, we studied prospectively 18 boilermakers overhauling an oil-fired boiler and 11 utility worker controls. Subjects completed a respiratory symptom diary five times per day by using a 0-3 scale where 0=symptom not present, 1=mild symptom, 2=moderate symptom, and 3=severe symptom. Daily symptom severity was calculated by using the highest reported score each day for upper and lower respiratory symptoms. Daily symptom frequency was calculated by summing all upper or lower airway symptom reports, then dividing by number of reporting times. Respiratory symptom frequency and severity were analyzed for dose-response relationships with estimated vanadium and PM(10) doses to the lung and upper airway by using robust regression. RESULTS: During the overhaul, 72% of boilermakers reported lower airway symptoms, and 67% reported upper airway symptoms. These percentages were 27 and 36 for controls. Boilermakers had more frequent and more severe upper and lower respiratory symptoms compared to utility workers, and this difference was greatest during interior boiler work. A statistically significant dose-response pattern for frequency and severity of both upper and lower respiratory symptoms was seen with vanadium and PM(10) in the three lower exposure quartiles. However, there was a reversal in the dose-response trend in the highest exposure quartile, reflecting a possible healthy worker effect. CONCLUSIONS: Boilermakers experience more frequent and more severe respiratory symptoms than utility workers. This is most statistically significant during boiler work and is associated with increasing dose estimates of lung and nasal vanadium and PM(10).     

Respiratory health effects of long-term exposure to different chromium species in stainless steel production

The aim of this study was to determine whether occupational exposure to chromite, trivalent chromium (Cr(3+)) or hexavalent chromium (Cr(6+)) causes respiratory diseases, an excess of respiratory symptoms, a decrease in pulmonary function or signs of pneumoconiosis among workers in stainless steel production. Altogether, 203 exposed workers and 81 referents with an average employment of 23 years were investigated for indicators of respiratory health on two occasions, in 1993 and in 1998. Data collection with a self-administered questionnaire, flow volume spirometry, measurement of diffusing capacity, chest radiography and laboratory tests were carried out by a mobile research unit. Exposure to different chromium species and other metals was monitored regularly and studied separately. No adverse respiratory health effects were observed in the group exposed to Cr(6+), either in comparison with the control group in the first cross-sectional study or during the additional 5 year follow-up. Among the Cr (3+) exposed people, the production of phlegm, shortness of breath and breathlessness on exertion were significantly more frequent than in the control group, but the frequency of the symptoms did not increase during the follow-up; no differences were observed in the lung function tests and the radiographic findings did not progress. In the chromite group, the prevalence of breathlessness on exertion was higher than in the control group. However, in the follow-up, the occurrence of symptoms did not differ from 1993 to 1998. In the first study, most parameters of lung function were lower among the smokers in the chromite group than among the smoking controls, but in 1998 the difference was less marked. An average exposure time of 23 years in modern ferrochromium and stainless steel production and low exposure to dusts and fumes containing Cr(6+), Cr(3+), nickel and molybdenum do not lead to respiratory changes detectable by lung function tests or radiography. The workers exposed to Cr(3+) had more respiratory symptoms than those in the control group. The workers in the chromite mine had lower lung function test results than the control group due to earlier exposure to higher dust concentrations.     

Evaluation and comparison of respiratory symptoms and lung capacities in tile and ceramic factory workers of Yazd

Tile workers are exposed to dust particles and are susceptible to multiple pulmonary complications. Problems like asthma, chronic obstructive pulmonary symptoms, and silicosis are more common among them. As there are many tile factories in Yazd, we decided to evaluate the respiratory symptoms and lung capacities in these workers and compare them with controls. This study included 176 tile and ceramic factory workers occupationally exposed to dust and 115 unexposed workers as controls. We recorded the respiratory symptoms using the British Medical Research Council questionnaire and measured lung capacities of the two groups.All study subjects were male, and the two groups were comparable in age and smoking. The exposed group had frequent respiratory symptoms and a significant relationship between them and duration of employment. In addition, lung capacities in ceramic workers with symptoms were lower than in workers without the symptoms. Even though the respiratory symptoms were more frequent in the exposed group than in controls, lung capacities of the two groups were similar.     

Lack of combined effects of exposure and smoking on respiratory health in aluminium potroom workers

OBJECTIVE: To investigate the combined influence on respiratory health of smoking and exposure in an aluminium potroom. METHODS: In a cross sectional study of 75 potroom workers (23 never smokers, 38 current smokers, 14 ex-smokers) and 56 controls in the same plant (watchmen, craftsmen, office workers, laboratory employees; 18 non-smokers, 21 current smokers, 17 ex-smokers), prevalences of respiratory symptoms and spirometric indices were compared. RESULTS: Smokers in the potroom group had a lower prevalence of respiratory symptoms than never smokers or ex-smokers, which was significant for wheezing (2.6% v 17.4% and 28.6% respectively, both p < 0.01), whereas respiratory symptoms in controls tended to be highest in smokers (NS). No effects of potroom work on the prevalence of respiratory symptoms could be detected. In potroom workers, impairment of lung function due to occupational exposure was found only in non-smokers, with lower results for forced vital capacity (FVC) (98.8% predicted), forced expiratory volume in one second (FEV1) (96.1% predicted) and peak expiratory flow (PEF) (80.2% predicted) compared with controls (114.2, 109.9, and 105.9% predicted; each p < 0.001). Conversely, effects of smoking on lung function were only detectable in non-exposed controls (current smokers v non-smokers: FVC 98.8% v 114.2% predicted; p < 0.01; FEV1 95.5 v 109.9% predicted; p < 0.05). CONCLUSIONS: In a cross sectional survey such as this, the effects of both smoking and occupational exposure on respiratory health may be masked in subjects with both risk factors. This is probably due to strong selection processes which result in least susceptible subjects continuing to smoke and working in an atmosphere with respiratory irritants.

 

     

Worker exposure to a herbicide applied with ground sprayers in the United Kingdom

This study was designed to measure potential dermal and respiratory exposure of agricultural workers during the application of a typical herbicide, 2,4-dichlorophenoxy acetic acid, with five types of application equipment commonly used in the United Kingdom. The workers were monitored during filling and loading operations and during spray application. Potential dermal exposure was higher during mixing and loading all tractor-powered sprayers than during spraying. Potential dermal exposure from tractor-powered sprayers fitted with conventional hydraulic nozzles was lower than from knapsack sprayers, with exposure from a tractor-powered sprayer fitted with controlled-droplet application equipment intermediate in this regard. There was no difference in potential dermal exposure between tractor-mounted and tractor-drawn sprayers fitted with conventional hydraulic nozzles. The hands were the most highly exposed part of the body during mixing and loading operations for all sprayers, and during spraying with tractor-powered sprayers. The lower legs of the workers were exposed principally when knapsack sprayers were used. For all five sprayers, potential respiratory exposure, where detectable at all, was negligible compared with potential dermal exposure.     

Immunologic changes and pulmonary ventilatory function in animal feed processing workers]

Respiratory symptoms and immunological reactions were examined in 35 animal food workers. The most frequent positive skin prick reactions occurred to fish flour (82.9%), followed by carotene (77.1%), cornflour (65.7%), four-leaf clover (62.9%), sunflower (54.3%), chicken meat (31.4%), soy (28.6%) and yeast (22.7%). The IgE serum level was increased in 40% of the animal food workers and in 2.6% of the controls. A significantly higher prevalence of chronic respiratory symptoms was found in animal food workers than in controls. However, there was no significant difference in prevalence of chronic respiratory symptoms between workers with positive and those with negative skin tests to house dust and fish flour or between those with increased and those with normal IgE levels (except for dyspnoea). There were significant acute across-shift reductions in ventilatory capacity, particularly for FEF25. The workers with positive skin tests to fish flour demonstrated significantly larger acute FEF25 reductions than those with negative skin tests. An extract of animal food caused constriction of isolated guinea pig tracheal smooth muscle in vitro. It appears that animal food dust in addition to immunological response may produce a direct irritative effect on the airways of exposed workers.     

Environmental and health studies of farm workers in Swedish swine confinement buildings.

The relation between the health of workers and the environment in swine confinement buildings was investigated in a study of 57 workers on 30 swine farms in southern Sweden and 55 matched controls. Swine workers reported significantly higher frequencies of respiratory symptoms, more frequent colds and absence due to chest illness, and a history of pneumonia. The increased frequency of symptoms of respiratory disease was related to the number of years and percent of the day spent working with swine. Symptoms were also associated with respirable dust, total dust, endotoxin in total dust, and number of microbes in the air of the work environment. In a multiple regression analysis of the relation between 16 different environmental parameters to work period shifts of five pulmonary function parameters, endotoxin was found to be significantly related to the FEV1 in a dose dependent way.