Season, equipment, and job function related to gastrointestinal problems in waste collectors

Assessing the exposure of street sweeping and potential risk factors for developing musculoskeletal disorders and related disabilities: a cross-sectional study

OBJECTIVE

This study aims to assess the exposure of those involved in street sweeping to the development of musculoskeletal disorders (MSDs) and related disabilities and tries to identify the individual risk factors thereof.

DESIGN

A cross-sectional survey was conducted among street sweepers together with a comparison group. A modified Standardized Nordic Questionnaire was adopted to measure the prevalence of MSDs and related disabilities. The impact of the occupation of sweeping on the development of MSDs and related disabilities was assessed using the propensity score matching (PSM) method. A multivariate logistic regression model was employed to identify the individual risk factors.

PARTICIPANTS

Street sweepers (n=180) and a comparison group (n=180), working for at least a year as formal employees of the Municipal Corporation of Greater Mumbai (MCGM), were randomly selected from 6 municipal wards.

RESULTS

The prevalence of the MSDs was significantly higher among the sweepers for shoulders (32%), wrists/hands (29%), elbows (27%) and neck (17%) compared with the comparison group, in which the prevalence was 11%, 19%, 9% and 11%, respectively. The disabilities too were significantly higher among the street sweepers for the lower back (27%), upper back (27%), wrists/hands (26%), shoulders (24%) and elbows (23%) compared with the comparison group, for which the figures were 18%, 19%, 13%, 9% and 6% respectively. The PSM method highlighted that the occupation of sweeping raised the risk of developing MSDs and disabilities particularly for the shoulders (17-16%), wrists/hands (14% each), elbows (13% each) and the upper back (12-13%). After adjusting the age, body mass index and the caste of the street sweepers, the number of years of engagement in street sweeping and the location of work emerged as potential risk factors in the development of MSDs and, thereby, related disabilities.

CONCLUSIONS

The study concluded that the occupation of street sweeping raises the risk of MSDs and related disabilities. This study recommends preventive and curative measures to deal with MSDs among street sweepers.

Respiratory Health in Waste Collection and Disposal Workers

Waste management, namely, collection, transport, sorting and processing, and disposal, is an issue of social concern owing to its environmental impact and effects on public health. In fact, waste management activities are carried out according to procedures that can have various negative effects on the environment and, potentially, on human health. The aim of our study was to assess the potential effects on respiratory health of this exposure in workers in the waste management and disposal field, as compared with a group of workers with no occupational exposure to outdoor pollutants. The sample consisted of a total of 124 subjects, 63 waste collectors, and 61 office clerks. Informed consent was obtained from all subjects before inclusion in the study. The entire study population underwent pulmonary function assessments with spirometry and completed two validated questionnaires for the diagnosis of rhinitis and chronic bronchitis. Statistical analyses were performed using STATA 13. Spirometry showed a statistically significant reduction in the mean Tiffenau Index values in the exposed workers, as compared with the controls, after adjusting for the confounding factors of age, BMI, and smoking habit. Similarly, the mean FEV1 values were lower in the exposed workers than in the controls, this difference being again statistically significant. The FVC differences measured in the two groups were not found to be statistically significant. We ran a cross-sectional study to investigate the respiratory health of a group of workers in the solid waste collection and disposal field as compared with a group of office workers. In agreement with most of the data in the literature, our findings support the existence of a prevalence of respiratory deficits in waste disposal workers. Our data suggest the importance of adopting preventive measures, such as wearing specific individual protection devices, to protect this particular category of workers from adverse effects on respiratory health.

Adverse health problems among municipality workers in alexandria (egypt)

BACKGROUND

Solid waste management has emerged as an important human and environmental health issue. Municipal solid waste workers (MSWWs) are potentially exposed to a variety of occupational biohazards and safety risks. The aim of this study was to describe health practices and safety measures adopted by workers in the main municipal company in Alexandria (Egypt) as well as the pattern of the encountered work related ill health.

METHODS

A cross-sectional study was conducted between January and April 2013. We interviewed and evaluated 346 workers serving in about 15 different solid waste management activities regarding personal hygiene, the practice of security and health care measures and the impact of solid waste management.

RESULTS

Poor personal hygiene and self-care, inadequate protective and safety measures for potentially hazardous exposure were described. Impact of solid waste management on health of MSWWs entailed high prevalence of gastrointestinal, respiratory, skin and musculoskeletal morbidities. Occurrence of accidents and needle stick injuries amounted to 46.5% and 32.7% respectively. The risk of work related health disorders was notably higher among workers directly exposed to solid waste when compared by a group of low exposure potential particularly for diarrhea (odds ratio [OR] = 2.2, 95% confidence interval [CI] = 1.2-3.8), vomiting (OR = 2.7, 95% CI = 1.1-6.6), abdominal colic (OR = 1.9, 95% CI = 1.1-3.2), dysentery (OR = 3.6, 95% CI = 1.3-10), dyspepsia (OR = 1.8, 95% CI = 1.1-3), low back/sciatic pain (OR = 3.5, 95% CI = 1.8-7), tinnitus (OR = 6.2, 95% CI = 0.3-122) and needle stick injury (OR = 3.4, 95% CI = 2.1-5.5).

CONCLUSIONS

Workers exposed to solid waste exhibit significant increase in risk of ill health. Physician role and health education could be the key to assure the MSWWs health safety.

Respiratory disorders among municipal solid waste collectors in Mansoura, Egypt: a comparative study

ABSTRACT This research assessed the prevalence of respiratory complaints and the occupational risk factors among municipal solid waste (MSW) collectors. A comparative study was conducted upon MSW collectors in Western Municipality of Mansoura. Sociodemographic and occupational data were collected. Clinical examination and respiratory function measurements were performed. The prevalence of respiratory complaints during the past 12 months was higher among MSW collectors than the service worker group. Older age, cigarette smoking, and longer duration of employment were independently associated with impaired FEV1 (OR = 0.22, 7.2, 0.09, respectively). Older age group of collectors was independently associated with impaired FVC (OR = 0.34). Longer duration of employment was independently associated with impaired FEV1/ FVC (OR = 0.09). Respiratory complaints were prevalent among MSW collectors due to lack of engineering, medical and legislative measures.

Municipal landfill sites as sources of microorganisms potentially pathogenic to humans

The present research was aimed at assessing the quality of air and soil on the premises and in the vicinity of the municipal landfill sites in Toruń with regard to the presence of pathogenic bacteria, potentially dangerous to humans. Air samples (the impaction method using a MAS-100 impactor) and soil samples were collected from seven sampling sites including the operating and closed landfill cells, sampling sites located near leachate ponds, and sampling sites located outside the above premises. The research also involved assessing microbial air contamination in three indoor spaces on the premises of the landfill sites. Microbial tests involved the determination of the number of culturable mesophilic, mannitol-positive, and α- and β-hemolytic bacteria in the air, determination of the number of coliform bacteria, spore-forming Clostridium perfringens in soil, and the presence of Salmonella in soil. The results indicate that bioaerosol emitted by this municipal facility is the source of hemolytic bacteria (≤ 300 CFU m(-3) of air), as well as of pathogenic bacteria (Pseudomonas aeruginosa and Bacillus subtilis). The highest risk of exposure to biological agents was determined in the sorting facility. Over sixty percent of air samples in this sampling site presented high pollution degree with mesophilic bacteria (500-2000 CFU m(-3) of air) and over one fourth of air samples presented very high pollution degree (>2000 CFU m(-3) of air). Indoor air in other rooms was considered highly/moderately contaminated (100-2000 CFU m(-3) of air). The highest risk related to the presence of Salmonella, Clostridium perfringens, and coliform bacteria in soil was determined at the operating landfill cell and near the leachate pond of the closed landfill cell. At the operating landfill cell the total coli ranged from 4-1226 MPN g(-1) of dry mass of soil and Clostridium perfringens ranged from <LOD-1604 CFU g(-1) of dry mass of soil. The results question the strategy of municipal landfill sites in densely populated areas, and emphasize the need for regular monitoring of microbiological tests in their vicinity as well as for control strategies in order to protect workers at landfill sites. The results of the study should be used for future decisions on the location of municipal landfill sites and suggest the need for better environmental control technologies in the sites that are already functioning.

A field study on the physiological workload of garbage collectors in the Japanese summer

A field study designed to reveal the physiological workload on garbage collectors (GC) was conducted in Japan. Three drivers who only operated a garbage truck, three loaders who actually collected as a team, three solo collectors, and one clerical worker, totaling 10 male workers participated in this study. The ambient temperature and the relative humidity, activity intensity, and heart rate were measured on the three days in July. The mean heart rate of the workers, excluding the clerical worker, was 97.5 bpm. There were cases in which the heart rate limit, as defined by ACGIH, was exceeded, including a case in which the loader sustainably exceeded this limit for over an hour. There were 10 worker-days in which the 58%HRmax level (corresponding to the permissible limit specified in the Netherlands) was exceeded based on the findings of the 18 worker-days for the loaders and solo collectors. There were many cases in which the energetic load of GC in the humid summertime in Japan exceeded the permissible limits as established in the U.S.A. and the Netherlands. The careful inspection of the actual work conditions and improvements in the work environment should be implemented for the occupational safety and health of GC.

Hepatitis B virus infection and waste collection: prevalence, risk factors, and infection pathway

BACKGROUND

Waste collectors have a potential risk of infectious diseases. The aim of the study was to assess; the prevalence of hepatitis B (HBV), risk factors for infection and possible ways of virus transmission among municipal solid waste workers (MSWWs) in a municipality of central Greece.

METHODS

A cross-sectional study was conducted among the employees of a municipality in Central Greece. The prevalence of an HBV infection biological marker (anti-Hbc) and its association with exposure to waste, socio-demographic factors, and history of occupational injuries with sharp objects/needle sticks was examined among 208 employees.

RESULTS

The prevalence of HBV infection among the municipal waste collectors was 23%. Logistic regression analysis showed that exposure to waste (OR = 4.05;95%CI = 1.23-13.33) and age (OR = 5.22;95% CI = 1.35-20.1) were independently associated with the anti-Hbc positivity. Moreover, waste collectors who reported occupational injuries with needle sticks were at higher risk of HBV infection (RR = 2.64; 95% CI = 1.01-6.96).

CONCLUSIONS

Occupational exposure to waste is a possible risk factor for HBV infection. Occupational injury with sharp instruments could be a means of hepatitis B virus transmission. Immunization of MSWWs and adoption of more safe ways for waste collection could be considered in order to control the risk of HBV infection.

An assessment of dust, endotoxin, and microorganism exposure during waste collection and sorting

This study was conducted to assess inhalation exposure to dust, endotoxin, and microorganisms (including viable bacteria, Gram-negative bacteria [GNB], and fungi) during waste collection and sorting; to identify factors affecting this exposure; and to estimate the gastrointestinal exposure to microorganisms. A total of 48 or 49 workers involved in collecting and sorting waste from households or the street were studied. Each worker carried two personal samplers in which filters were placed in the breathing zone for estimation of inhalation exposure. To assess the possibility of gastrointestinal exposure, microorganisms on the workers' faces were collected before and after work and compared with those collected from office workers. Inhalation exposure levels were categorized according to job title, waste type handled, and working conditions and were compared using analysis of variance. Multiple regression models were developed to identify those factors that substantially affected inhalation exposure. The average exposure level to total dust was 0.9 mg/m3 (range = 0.05 to 4.51 mg/m3), and the average exposure to endotoxin was 1123 EU/m3. The average respective exposure levels to bacteria, GNB, and fungi each exceeded 10(4) colony forming units (CFU)/m3. The multiple regression models found several factors that significantly explained the variation in levels of inhalation exposure to endotoxin and microorganisms; namely, sex (dust, bacteria, and GNB), job title (GNB and fungi), collection day (dust, bacteria, and GNB), temperature (endotoxin and GNB), humidity (endotoxin and fungi), and region (endotoxin) were significantly associated with exposure to these agents. In addition, the workers' faces were highly contaminated with microorganisms. In conclusion, inhalation exposure to endotoxin and microorganisms was high during waste collection and sorting, which may place workers at risk of developing various health problems, including respiratory complaints.

Health and safety in waste collection: Towards evidence-based worker health surveillance

BACKGROUND

Waste collectors around the world are at risk for work-related disorders and injuries. The aim of this study was to assess work demands, acute physiologic responses, illnesses, and injuries as a starting point for worker health surveillance (WHS).

METHODS

A systematic search was performed in PubMed and Embase on work demands, acute bodily responses, health, and injuries. A quality assessment and evidence synthesis was performed.

RESULTS

From a total of 379 retrieved studies, 50 studies fulfilled the inclusion criteria. Waste collecting varied from informal manual gathering to semi-automated systems. Most studies ("number of studies") on work demands and/or acute bodily responses addressed bioaerosols (14). Studies of health effects addressed respiratory complaints (8), and those on injuries addressed acute musculoskeletal disorders (3). Strong evidence is available that exposure to bioaerosols exceeds recommendations. Moderate evidence is available for an increased risk of respiratory complaints and musculoskeletal injuries, with significant odds ratios reported varying between 1.9-4.1 and 1.5-3.3, respectively. Limited evidence exists for gastrointestinal disorders and hearing loss.

CONCLUSIONS

WHS in waste collection is warranted for early detection of respiratory, gastrointestinal, and musculoskeletal disorders, and hearing loss.

Indicadores infecciosos e inflamatórios entre trabalhadores da limpeza urbana em São Paulo

O objetivo deste trabalho foi comparar agravos à saúde entre grupos funcionais de trabalhadores da limpeza urbana (TLU) decorrentes de exposição biológica do contato com os Resíduos Sólidos (RS) em São Paulo, 2007. Para tal, amostras dos grupos de TLU e um grupo Controle de servidores ferroviários realizaram entrevistas, contagens sanguíneas, provas de atividade inflamatória, marcadores sorológicos de infecção e exame protoparasitológico de fezes.Ao término, foram avaliados 217 indivíduos. O grupo Controle relatou menor cobertura vacinal para o tétano, enquanto os Varredores tiveram a menor proporção de cobertura para a hepatite B. Os Motoristas usaram mais antibióticos e apresentaram o número de leucócitos mais elevado quando comparados aos Controles. Os Motoristas apresentaram também maiores médias de neutrófilos e monócitos quando comparados aos Varredores. A presença de parasitas nas fezes foi mais frequente entre os Varredores e os Coletores quando comparados aos Controles. Os grupos de Coleta, Transbordo e Aterro apresentaram indicadores de infecções respiratórias e de atividade inflamatória sistêmica similares aos Controles. Não foram observadas diferenças entre episódios de sinusites, pneumonias, marcadores séricos de atividade inflamatória, contato com o vírus da hepatite B ou com a estreptolisina O entre os grupos estudados.

Change in airway responsiveness over a workweek in organic waste loaders

OBJECTIVE

Organic waste workers are exposed to high endotoxin levels that may result in respiratory health effects. This study describes changes in lung function and methacholine airway responsiveness over a workweek in household organic waste loaders.

METHODS

Assessment of lung function and methacholine airway responsiveness before and after a workweek in six organic waste loaders with and ten loaders without regular respiratory symptoms. Methacholine responsiveness was expressed as dose-response slope, i.e. % fall in FEV(1) per mg methacholine compared to either the post-saline value (DRS(sal)), or the highest FEV(1) (DRS(max)).

RESULTS

Monday morning, FEV(1) was similar in cases and controls. Over the workweek, FEV(1) and MMEF decreased slightly in both cases and controls (P > 0.10). In contrast, DRS increased in cases and decreased in control subjects (P < 0.10). The difference in % change of DRS was statistically significant after adjustment for smoking and age.

CONCLUSION

Our results suggest exaggeration of pre-existent airway inflammation during the workweek in organic waste loaders with regular respiratory symptoms. This needs confirmation in larger studies.

Exposure to aerosolized bacteria and fungi among collectors of commercial, mixed residential, recyclable and compostable waste

Biological hazards associated with the collection of solid and compostable waste have not been well characterized in North America. This is an issue because workers who handle such materials may be exposed to bioaerosols (airborne bacteria and fungi) and dusts resulting in infections or allergic diseases. We conducted a personal sampling campaign for culturable bacteria and fungi in the breathing zones of waste collectors in a variety of typical work settings (scenarios) in the province of Quebec, Canada. Total culturable bacterial and fungal counts were analyzed and compared to ambient environmental levels (background) to determine the degree of incremental exposure among workers. In several scenarios, worker exposure counts were significantly (p < or = 0.05) higher than ambient levels measured upwind, with the highest personal exposures to bacteria observed for urban compostable waste collectors (median = 50,300 Colony Forming Units/m(3) of air (CFU/m(3))). On the other hand, fungal counts collected on an every-other-week cycle were highest among a group of rural compostable waste collectors (median = 101,700 CFU/m(3)). Similar exposures to culturable bacteria and fungi have been reported in European workers who showed such adverse health effects as nausea, diarrhea, upper respiratory tract irritation, and allergy. Therefore, it may be necessary to modify certain work practices in order to minimize exposure. Recommendations include automation of waste and compost collection, use of personal protective equipment including goggles, gloves, and disposable masks, and meticulous personal hygiene.

Clara cell protein and surfactant protein�B in garbage collectors and in wastewater workers exposed to bioaerosols

OBJECTIVES

Inhalation of bioaerosols has been hypothesised to cause "toxic pneumonitis" that should increase lung epithelial permeability at the bronchioloalveolar level. Serum Clara cell protein (CC16) and serum surfactant protein B (SPB) have been proposed as sensitive markers of lung epithelial injury. This study was aimed at looking for increased lung epithelial permeability by determining CC16 and SPB in workers exposed to bioaerosols from wastewater or garbage.

METHODS

Subjects (778 wastewater, garbage and control workers; participation 61%) underwent a medical examination, lung function tests [American Thoracic Society (ATS) criteria], and determination of CC16 and SPB. Symptoms of endotoxin exposure and several potential confounders (age, gender, smoking, kidney function, obesity) were looked for. Results were examined with multiple linear or logistic regression.

RESULTS

Exposure to bioaerosols increased CC16 concentration in the wastewater workers. No effect of exposure on SPB was found. No clue to work-related respiratory diseases was found.

CONCLUSIONS

The increase in CC16 in serum supports the hypothesis that bioaerosols cause subclinical "toxic pneumonitis", even at low exposure.

Morbidity among municipal waste incinerator workers: a cross-sectional study

OBJECTIVES

In order that the occupational exposures and health risks for municipal waste incinerator operators be better determined, a study was carried out in three centres.

METHODS

A transversal study was carried out for 102 male incinerator workers matched for age with 94 male workers from other industrial activities. Three groups of exposed workers were considered (group 1: "crane operators" and "equipment operators"; group 2: "furnace " workers; group 3: "maintenance" and "effluent-treatment" workers). Data were collected through a questionnaire and medical examination. The respiratory function was explored and blood samples were taken for biological analysis. Statistical analysis using chi(2) or Student's test, and calculation of odds-ratio (OR) using logistic regression analysis were performed.

RESULTS

There were no significant differences in general symptoms between the two groups. Skin symptoms (OR =4.85; 2.04-11.51 for the "maintenance and effluent" workers) were more often observed in the exposed group. An excess of respiratory problems was also encountered: daily coughing ["maintenance and effluent" groups (OR =2.55; 0.84-7.75); "furnace men" (OR =6.58; 2.18-19.85)]. A significant relationship between exposure and the decrease of several pulmonary parameters was observed. The liver and haematological tests were well within the normal range; nevertheless, a slight but significant increase in the white blood cells was observed in the exposed group. Higher blood lead levels were found for exposed workers.

CONCLUSION

There were few adverse health effects in our morbidity study but skin irritation and cough were more frequent in the exposed workers. A slight decrease in pulmonary function was observed. These findings are in agreement with those of several other studies.

Organic dust exposure and work-related effects among recycling workers

OBJECTIVE

Organic dust exposure and work-related symptoms and effects among household waste recycling workers in Materials Recovery Facilities (MRFs) are a concern. MRFs are a central operation where source-segregated, dry, recyclable materials (paper, plastics, cans, etc.) are sorted, mechanically or manually, to market specifications for processing into secondary materials.

METHODS

One hundred and fifty-nine MRF workers (91%) from nine MRFs participated. Measurements of airborne total dust, endotoxin, (1-->3)-beta-D-glucan, and a questionnaire survey were carried out. Blood data was restricted to MRFs 3, 6, and 9 (45 workers). Blood sampling investigated differential cell counts, erythrocyte sedimentation rate (ESR), and immunoglobulin (Ig)E.

RESULTS

Workers exposed to higher amounts of endotoxin and (1-->3)-beta-D-glucan had an increased risk for respiratory symptoms as compared to those with lower exposure. Stomach problems was associated to higher (1-->3)-beta-D-glucan exposure. MRF 3 had a higher (1-->3)-beta-d-glucan exposure compared to 6 and 9, and respiratory symptoms, unusual tiredness, and vomiting were reported more often in MRF 3. Monocyte numbers and ESR were significantly decreased in MRF 3 compared to MRF 6 and 9, but all measured values were within normal ranges.

CONCLUSIONS

The results suggest that MRF workers exposed to higher levels of endotoxin and (1-->3)-beta-D-glucan at their work sites exhibit various work-related symptoms, and that the longer a worker is in the MRF environment, the more likely he is to become affected by various respiratory and gastrointestinal symptoms.

Upper airway inflammation and respiratory symptoms in domestic waste collectors

OBJECTIVES

To compare respiratory symptoms and upper airway inflammation in domestic waste collectors and controls, and to find the association between measures of upper airway inflammation on the one hand and exposure concentrations of organic dust or respiratory symptoms on the other hand.

METHODS

In a cross sectional study among 47 waste collectors and 15 controls, questionnaire data on respiratory symptoms were collected. Nasal lavage (NAL), to assess upper airway inflammation, was performed before and after a work shift at the beginning and at the end of the working week. In NAL fluid, cells were counted and differentiated and concentrations of interleukin 6 (IL6), IL8, tumour necrosis factor-alpha (TNF alpha), and IL1 beta were measured. In collectors, inhalable dust samples were collected in which bacterial endotoxin and mould beta(1-->3)-glucan were assessed.

RESULTS

Prevalence of respiratory symptoms was higher in waste collectors than in controls. Geometric mean exposure concentrations were 0.58 mg/m(3) for dust, 39 EU/m(3) for endotoxin, and 1.3 microg/m(3) for beta(1-->3)-glucan. At the end of the week collectors had higher concentrations of total cells and IL8 in NAL before and after a shift than controls (cells, before 1.9-fold p<0.10, after 3.3-fold p<0.01; IL8, before and after 1.8-fold p<0.05), and after/before work shift ratios of total cells were also higher (2.3-fold p=0.06) in collectors than in controls. Cells in NAL fluid consisted predominantly of neutrophils and epithelial cells, whereas eosinophils and mononuclear cells were rarely found. Exposure to dust and endotoxin was associated with concentrations of IL8 after the shift (p<0.05). Increased concentrations of IL8 (p<0.05) and total cells (p<0.10) after the shift were associated with respiratory symptoms. Concentrations of IL6, TNF alpha, and IL1 beta were not associated with waste collecting, symptoms, or exposure.

CONCLUSIONS

Waste collectors show signs of increased upper airway inflammation and respiratory symptoms compared with controls. Exposure to organic dust probably underlies the inflammation mediated by neutrophils that result in respiratory symptoms.

Adverse health effects among household waste collectors in Taiwan

Household waste collectors (HWCs) are potentially exposed to a variety of bioaerosols and toxic materials. Collection of household waste is also a job which requires repeated heavy physical activity such as lifting, carrying, pulling, and pushing. The object of this study was to assess whether there is an excess of adverse health outcomes among HWCs. The subjects were all current employees of the Household Waste Collection Department in the County of Kaohsiung, Taiwan. The survey questionnaire was completed by 533 HWCs and 320 office workers. Our data indicate that household waste collection presents a risk for the development of chronic respiratory symptoms (cough, phlegm, wheezing, and chronic bronchitis), musculoskeletal symptoms (low back pain and elbow/wrist pain), and injuries caused by sharp objects.

Health complaints and immunological markers of exposure to bioaerosols among biowaste collectors and compost workers

OBJECTIVES

In a cross sectional study, work related health complaints and diseases of 58 compost workers and 53 biowaste collectors were investigated and compared with 40 control subjects. Levels of specific IgG antibodies to moulds and bacteria were measured as immunological markers of exposure to bioaerosols.

METHODS

With a standardised protocol, the participants of the study were interviewed for work related symptoms, conditions of exposure to bioaerosols at their workplaces, exposure to bioaerosols from other sources, atopic diseases, and smoking habits. They were clinically examined by physicians specialised in occupational medicine. Also, concentrations of specific IgG antibodies against antigens of moulds and actinomycetes occurring regularly at these workplaces were measured and compared with the health complaints of the workers.

RESULTS

Compost workers had significantly more symptoms and diseases of the airways (p=0.003) and the skin (p=0.02) than the control subjects. Health complaints of biowaste collectors did not differ significantly from those of the control group. Subjects with atopic diseases were underrepresented in the compost workers (p=0.003). Significantly increased antibody concentrations against fungi and actinomycetes were measured in workers at composting plants. The concentrations in biowaste collectors did not differ significantly from those in the control subjects. A significant association between the diseases and increased antibody concentrations were found in the compost workers.

CONCLUSION

The high exposure to bioaerosols of compost workers is significantly associated with a higher frequency of health complaints and diseases as well as higher concentrations of specific antibodies against moulds and actinomycetes. A healthy worker effect is indicated by the underrepresentation of atopic diseases among the compost workers compared with biowaste collectors and the control group.

Health effects among workers in sewage treatment plants

OBJECTIVES

To further assess the presence of fatigue, symptoms of diarrhoea, and inflammation of airways among people working in sewage plants and the relation to airborne bacterial endotoxin at the workplace.

METHODS

34 Employees in sewage treatment plants and 35 controls were selected. They underwent a questionnaire investigation, and spirometry and airway responsiveness were measured. Measurements were made of airborne endotoxin at different workplaces.

RESULTS

The amount of airborne endotoxin varied between 3.8 and 32,170 ng/m3. Workers reported significantly higher nose irritation, tiredness, and diarrhoea. Airway responsiveness was increased among sewage workers, but no differences between the groups were found for spirometry.

CONCLUSIONS

The results confirm previous studies on the presence of airways and intestinal inflammation among workers in sewage treatment plants. The most likely causative agent is endotoxin, and at 14 of 23 workplaces, concentrations exceeded recommended guidelines.