Bespoke latex allergen testing improves assessment of respiratory symptoms in textile-braiding workers.

BACKGROUND: Latex allergy is poorly understood in latex-exposed textile workers. METHODS: A cross-sectional study was carried out to better characterize respiratory symptoms, using personal breathing zone latex allergen measurement and specific IgE to latex allergens. RESULTS: Forty-four of the 86 (51% participation rate) participated. Ten of 39 workers who gave a blood sample (25.6%) were found to have IgE to at least one workplace allergen (5/39 positive to either latex braiding coated with silica or talc, 4/39 were positive to the dyed cotton extract, and 1/39 to latex braiding coated with silica or talc and dyed cotton extract), whilst only 2 of these 10 had specific IgE to the commercial latex extract. CONCLUSIONS: The presence of symptoms with evidence of sensitization was strongly dictated by current latex exposure. Bespoke workplace allergen IgE testing identified cases of WR respiratory symptoms with sensitization that otherwise would not have been identified.

Sensitization and symptoms associated with soybean exposure in processing plants in South Africa.

BACKGROUND: Following the results of a previous study that highlighted the potential for significant levels of dust exposure in South African soybean processing plants, a clinical investigation was undertaken to study the respiratory health of workers in this industry. METHODS: Workers from three soybean-processing plants were studied with a respiratory questionnaire and estimation of atopy and specific soybean IgE. RESULTS: A total of 144 of the 181 (79.6% participation rate) plant employees completed the questionnaire and 136 (75.1%) gave blood samples for analysis of specific IgE. There was a significant association between work-related chest tightness (OR 4.0 [95% CI 1.3-12.6]), work-related nasal symptoms (OR 4.3 [95% CI 1.3-14.6]) and cough or chest tightness after handling soybean (OR 3.6 [95% CI 1.1-11.6]) and soybean sensitization. There was a significant association between current exposure to dust during soybean off-loading and "flu-like" illness (OR 2.7 [95% CI 1.0-7.2]), and cough or chest tightness after such work (OR 7.4 [95% CI 2.4-23.6]). The strongest predictor of work related nasal symptoms was sensitization to soybean, the latter strongly predicted by the presence of atopy (OR 34.7 [95% CI 6.6-182.5]). CONCLUSIONS: Exposure and sensitization to soybean were associated with the presence of work related symptoms, including flu-like symptoms, cough, chest tightness, and nasal symptoms. The aetiology of these symptoms and more particularly the best intervention strategies require more detailed investigation.

Impact of worker education on respiratory symptoms and sensitization in bakeries.

BACKGROUND: Flour exposure is known to cause significant respiratory problems. AIMS: To investigate the development of work-related sensitization, the period between first exposure and the development of symptoms (latent period) and the impact of workplace training programmes on respiratory health in plant bakers. METHODS: Two hundred and sixty-four bakers were investigated by assessing work-related respiratory symptoms and latent period before symptoms/sensitization, spirometry and testing for an array of workplace-specific IgE. RESULTS: There was a significant relationship between the presence of work-related respiratory symptoms and flour dust allergen-specific IgE. Latent periods varied widely: median for work-related nasal symptoms 36 months, cough 42 months and chest tightness 120 months. Latent periods were shorter for workers with evidence of flour sensitization (work-related wheeze: mean 13 months with sensitization, 97 months without, P < 0.05, work-related nasal symptoms, respectively; mean 19 months, 71 months, P < 0.01). Those warned of the health implications of flour dust had less work-related wheeze (warned; 1%, not warned 11%, P < 0.05). There was an excess of work-related symptoms and work-related-specific IgE combined in those who had not been warned of these health implications (12 versus 1%, P <0.01). CONCLUSIONS: Reporting of 'being warned' of potential health implications from breathing flour dust protected strongly against the reporting of important health end points. Latent periods for the development of work-related symptoms varied widely. Simple health messages, which may be overlooked in worker training programmes, can have significant benefits for worker health in the bakery population.

Self-reported work-related symptoms in hairdressers.

BACKGROUND: Detailed studies of current symptoms reported by hairdressers and of the training received to reduce the health risks associated with this work are uncommon. AIMS: To document current levels of self-reported health problems in hairdressers, compared to non-hairdressing controls. METHODS: An interviewer-led questionnaire recording demographic information, work history, health training levels and the presence of self-reported respiratory, skin, musculoskeletal and non-specific symptoms was administered. RESULTS: In total, 147 hairdressers, 86% of whom were female (median age 27 years) and 67 non-hairdressing controls, all female (median age 38 years) were recruited. Following adjustment for age, smoking and years worked, hairdressers reported significantly higher levels of musculoskeletal problems, including work-related shoulder pain (OR 11.6, 95% CI 2.4-55.4), work-related wrist and hand pain (2.8, 1.1-7.6), work-related upper back pain (3.8, 1.0-14.9), work-related lower back pain (4.9, 1.5-15.9) and work-related leg/foot pain (31.0, 3.8-267.4). The frequency of self-reported asthma was similar in both groups (hairdressers 16%, controls 17%) as was chest tightness and wheeze. Work-related cough was significantly more frequently reported in hairdressers than in controls (13.2, 1.3-131.5). While hairdresser training was commonplace, such training did not always appear to have resulted in awareness of potential workplace health risks. CONCLUSIONS: This study identified frequently reported musculoskeletal, skin and respiratory symptoms in hairdressers. This points to a need to develop training that not only deals with risk assessment but also informs hairdressers about the health risks of their work.

Work-related symptoms in nail salon technicians.

BACKGROUND: Nail salons are a rapidly expanding small business sector. Environmental health practitioners have raised concerns about potential health and safety issues. AIMS: To establish the extent of work-related health issues reported by nail salon technicians, their knowledge of health and safety regulations and of the products used. METHODS: Nail technicians completed a researcher-administered questionnaire, and responses were compared to those of non-exposed office-based control subjects. RESULTS: In all, 39 of 588 nail salons approached agreed to participate (7%), with all 71 (100%) of the available nail technicians within these salons completing study questionnaires. The majority of the nail technicians (99%) had received training that had included aspects of health and safety and most reported being aware of the Control of Substances Hazardous to Health regulations (59/70, 84%) and risk assessments (65/70, 93%). Compared to the control group, the nail technicians reported statistically significant increased levels of work-related neck (OR 5.0, 95% CI 1.6-15.6), shoulder (15.0, 3.1-71.8), wrist/hand (3.6, 1.2-10.7) and lower back problems (3.5, 1.0-12.5). Work-related nasal symptoms were also significantly more common in nail technicians (6.2, 1.3-30.7). CONCLUSIONS: This study demonstrated a higher prevalence of a range of musculoskeletal problems and respiratory symptoms reported by nail technicians compared to office-based controls. An ergonomic and exposure assessment of work practices in this industry is warranted to identify the working practices associated with these symptoms, in order to inform best practice, supplement industry and regulatory guidance and develop appropriate practical work-based training.

Uptake and quality of health surveillance for noise and hand-arm vibration.

BACKGROUND: Health surveillance (HS) is required for employees if noise or hand-arm vibration (HAV) exposures are likely to be above exposure action levels. The extent to which employers comply with Health and Safety Executive (HSE) regulations is unclear. AIMS: To establish the uptake and quality of HS for noise and HAV in high-risk industries. METHODS: A cross-sectional telephone-based questionnaire study involving employers in high-risk industries for noise or HAV. RESULTS: A total of 246 and 386 interviews were completed for noise and HAV, respectively. The uptake of HS in the cohorts was 17 and 10%, respectively. Selection of those companies thought to have 'higher risk' increased the uptake to 25 and 18%, respectively. The proportion of companies carrying out HS was strongly related to the size of the company, with smaller companies less likely to provide this for their employees. A large proportion of companies that reported having HS in place had formal procedures for managing exposed workers (90 and 83% for noise and HAV, respectively), received feedback on individual workers (81 and 80%) and some reported that they used this information to inform their risk management process (58 and 63%). The frequency of HS for HAV was in line with that suggested in HSE guidance in 70% of cases, however, for noise, it was often utilized more frequently. CONCLUSIONS: While many of the companies appear to be following HSE guidance, there is a significant number that are not. Further initiatives that engage with smaller companies may help increase HS provision.

Respiratory symptoms in insect breeders.

BACKGROUND: A number of specialist food suppliers in the UK breed and distribute insects and insect larvae as food for exotic pets, such as reptiles, amphibians and invertebrates. AIMS: To investigate the extent of work-related (WR) symptoms and workplace-specific serum IgE in workers potentially exposed to a variety of biological contaminants, including insect and insect larvae allergens, endotoxin and cereal allergens at a UK specialist insect breeding facility. METHODS: We undertook a study of respiratory symptoms and exposures at the facility, with subsequent detailed clinical assessment of one worker. All 32 workers were assessed clinically using a respiratory questionnaire and lung function. Eighteen workers consented to provide serum for determination of specific IgE to workplace allergens. RESULTS: Thirty-four per cent (11/32) of insect workers reported WR respiratory symptoms. Sensitization, as judged by specific IgE, was found in 29% (4/14) of currently exposed workers. Total inhalable dust levels ranged from 1.2 to 17.9 mg/m(3) [mean 4.3 mg/m(3) (SD 4.4 mg/m(3)), median 2.0 mg/m(3)] and endotoxin levels of up to 29435 EU/m(3) were recorded. CONCLUSIONS: Exposure to organic dusts below the levels for which there are UK workplace exposure limits can result in respiratory symptoms and sensitization. The results should alert those responsible for the health of similarly exposed workers to the potential for respiratory ill-health and the need to provide a suitable health surveillance programme.

Optimized methods for fungal alpha-amylase airborne exposure assessment in bakeries and mills.

BACKGROUND: In order to enable reproducible and comparable exposure measurements of fungal alpha-amylase (alpha-amylase) in different laboratories and countries, the entire procedure from sampling of airborne dust to measuring extracted samples (including standards and the used enzyme) immunoassays must be standardized. The aim of this study was to establish optimal elution and assay conditions. METHODS: A parallel sampler was used for simultaneous collection of 10 samples of inhalable dust in bakeries and mills in Germany, England, the Netherlands and Spain. Three enzyme-immunoassays (EIAs) for detection of fungal alpha-amylase based on monoclonal antibodies or polyclonal antibodies were used for the measurement of the parallel-sampled filters (n=432) extracted using several methods. The results were analysed by regression analysis of variance. Additional filters (n=54) were extracted and analysed using two EIAs to investigate the storage stability of the extracts. RESULTS: Although alpha-amylase concentrations correlated well (r> or =0.88), differences were found between the EIAs in the sensitivity and nominal values (up to a mean factor 5.8). The best elution medium for airborne filters (phosphate-buffered saline 'PBS' with 0.05% Tween-20) led to 1.2 to two times higher alpha-amylase allergen yields than extraction in PBS only, while higher Tween-20 concentrations decreased the extracted alpha-amylase yield. During storage of frozen dust/filter extracts for 3-4 months at -20 degrees C, a loss of approximately 40% of measurable alpha-amylase was observed, which could be partially prevented by addition of 0.1% casein to the medium directly after extraction. CONCLUSION: Although the effects of only a few of many possible causes of variation were investigated, for these factors a clear choice could be made with regard to optimal elution conditions and the use of validated EIAs with calibrated standards, thus making significant progress towards a completely standardized procedure for airborne alpha-amylase measurements.

Approaches to the diagnosis and management of occupational asthma amongst UK respiratory physicians.

This study aimed to assess the approach to the diagnosis and management of occupational asthma amongst general (non-specialist) respiratory consultants in the UK. A random sample of 100 UK general respiratory physicians were invited to participate, and asked to provide information on their diagnostic approach to a case scenario of a patient with possible occupational asthma relating to flour exposure. Participation rates were 42% for the main part of the study. Less than half of consultants specifically reported they would ask whether symptoms improved away from work, and just over a third mentioned examining the patient. All of those interviewed recommended a chest X-ray, and 98% simple spirometry. Eighty-six per cent suggested measurement of serial peak flows, recorded for between 2 and 8 weeks, with measurements taken half-twelve hourly. Less than half advocated a specific flour allergy test, and almost one-quarter (23%) would not perform any immunological test at all. Once a diagnosis of occupational asthma was confirmed, less than two-thirds of those interviewed commented they would recommend some form of exposure reduction, and only 28% specifically stated they would offer compensation advice. The diagnosis of occupational asthma by general respiratory physicians within the UK lacks standardisation, and in some cases falls short of evidence-based best practise.

Clinical investigation of an outbreak of alveolitis and asthma in a car engine manufacturing plant.

BACKGROUND: Exposure to metal working fluid (MWF) has been associated with outbreaks of extrinsic allergic alveolitis (EAA) in the USA, with bacterial contamination of MWF being a possible cause, but is uncommon in the UK. Twelve workers developed EAA in a car engine manufacturing plant in the UK, presenting clinically between December 2003 and May 2004. This paper reports the subsequent epidemiological investigation of the whole workforce. The study had three aims: (1) to measure the extent of the outbreak by identifying other workers who may have developed EAA or other work-related respiratory diseases; (2) to provide case detection so that those affected could be treated; and (3) to provide epidemiological data to identify the cause of the outbreak. METHODS: The outbreak was investigated in a three-phase cross-sectional survey of the workforce. In phase I a respiratory screening questionnaire was completed by 808/836 workers (96.7%) in May 2004. In phase II 481 employees with at least one respiratory symptom on screening and 50 asymptomatic controls were invited for investigation at the factory in June 2004. This included a questionnaire, spirometry and clinical opinion. 454/481 (94.4%) responded and 48/50 (96%) controls. Workers were identified who needed further investigation and serial measurements of peak expiratory flow (PEF). In phase III 162 employees were seen at the Birmingham Occupational Lung Disease clinic. 198 employees returned PEF records, including 141 of the 162 who attended for clinical investigation. Case definitions for diagnoses were agreed. RESULTS: 87 workers (10.4% of the workforce) met case definitions for occupational lung disease, comprising EAA (n = 19), occupational asthma (n = 74) and humidifier fever (n = 7). 12 workers had more than one diagnosis. The peak onset of work-related breathlessness was Spring 2003. The proportion of workers affected was higher for those using MWF from a large sump (27.3%) than for those working all over the manufacturing area (7.9%) (OR = 4.39, p<0.001). Two workers had positive specific provocation tests to the used but not the unused MWF solution. CONCLUSIONS: Extensive investigation of the outbreak of EAA detected a large number of affected workers, not only with EAA but also occupational asthma. This is the largest reported outbreak in Europe. Mist from used MWF is the likely cause. In workplaces using MWF there is a need to carry out risk assessments, to monitor and maintain fluid quality, to control mist and to carry out respiratory health surveillance.