Quaternary ammonium compounds and occupational asthma

Objective: Quaternary ammonium compounds, among which benzalkonium chloride is one of the best-known, are commonly used as antiseptics, disinfectants, detergents and preservatives. They can cause occupational asthma, which however, has been rarely reported so far, despite wide use of these products. We report three such cases. Possible mechanisms causing asthma are discussed, taking into account their characteristics. Methods and results: Our patients, all female nurses, manifested asthma symptoms upon handling disinfectant solutions containing benzalkonium chloride. Work-related fall in PEFR was observed in all of them. The diagnosis was confirmed by challenge tests where the patients were exposed, in a closed chamber, to suspected disinfectant contained in a tray. All of the women developed early or delayed symptoms upon exposure. Similar challenge tests to placebo or other disinfectants devoid of quaternary ammonium compound were negative. Conclusion: These three cases, in addition to others reported in the literature, point out an as yet poorly known etiology of occupational asthma to quaternary ammonium compounds in hospital employees. The exact mechanism of the action remains unexplained. Received: 20 October 1999 / Accepted: 25 March 2000     

Opportunities and obstacles in translating evidence to policy in occupational asthma

Purpose

Occupational asthma (OA), a common respiratory disorder in Western countries, is caused by exposures at the workplace. It is part of a broader definition of work-related asthma (WRA) that also includes pre-existing asthma aggravated by substances present in the workplace environment, and it is potentially preventable. The purpose of this paper is to illustrate preventive measures for occupational asthma by case studies.

Prevention of occupational asthma including medical surveillance

The high figures of occupational asthma worldwide necessitate the intensification of appropriate primary, secondary, and tertiary preventive measures. Based on new scientific data on dose-response relationships as well as our own experience and ethical aspects, we focus on medical surveillance within the framework of secondary prevention. We propose that medical surveillance programs be mandatory for workplaces/occupations with an asthma incidence of ≥200% than that of the general population. Medical surveillance programs are recommended if asthma frequency is elevated but below 200%. A stepwise approach of monitoring workers at risk for developing occupational asthma including a screening by questionnaire and a personal interview and diagnosis confirmation is presented. In addition, we briefly comment on the management of affected subjects. Am. J. Ind. Med. 34:632–639, 1998. © 1998 Wiley-Liss, Inc.     

Occupational asthma in hairdressers: results of inhalation tests with bleaching powder

Study objective: To analyze the extent to which the clinical diagnosis of bleach-induced asthma can be confirmed by laboratory tests and to determine the role of work-related exposure to bleaching powder in a group of hairdressers with respiratory complaints. Methods: The study population consisted of 55 female hairdressers who had regular contact with various hair products and a clinical history of job-related rhinitic and/or asthmatic symptoms. We divided the individuals into two groups: group I, with asthmatic symptoms (n=38), and group II, without asthmatic symptoms (control group, n=17). All subjects underwent immunological, pulmonary-function, and nonspecific bronchial provocation tests, and 46 study participants were subjected to a standardized bleaching-powder test in a designated chamber. Results: There were 13 positive responses to bleaching powder in the skin test, and 32 individuals showed positive bronchial responsiveness to acetylcholine; positive responses to the challenge with bleaching powder occurred in 9 women (22% of those tested). None of the women in group II reacted to bleaching powder. There was no significant difference between persons with a positive or a negative bronchial provocation test with regard to the evaluated parameters. Conclusions: In the diagnostic workup of hairdressers with work-related respiratory symptoms, bleaching powder is one of the products that need to be tested. As not every patient with an asthmatic response to bleaching powder shows a positive response to the acetylcholine challenge test, in doubtful cases a specific exposure test may be recommendable. Received: 29 January 1997 / Accepted: 9 June 1997     

职业性哮喘患者肺功能变化的临床观察

目的了解职业性哮喘患者的肺功能变化特点。方法对15例职业性哮喘患者行支气管现场激发试验时的肺功能参数进行分析,并同时记录发生时间及患者症状、体征。结果①发作期和激发前肺功能值比较,大部分肺功能参数差异有统计学意义(P0.05)。发作期用力肺活量(FVC)、第1秒用力呼气容量(FEV1)、最大用力呼气流速(PEF)、最大呼气中段流速(MMEF)、25%和50%肺活量时的最大呼气流速(FEF25、FEF50)显著低于激发前;②经直线相关分析,FEV1与FVC下降率之间,FEF50与MMEF下降率之间以及FEV1与MMEF下降率之间均呈直线相关(rs=0.825,P=0.006;rs=0.992,P=0.000;rs=0.881,P=0.004)。③激发后60 min内现场支气管激发试验阳性10例,且全部出现全身发汗、颜面发绀及肺部哮鸣音等严重临床表现,占67%;激发2 h后的现场支气管激发试验阳性5例,占33%。结论职业性变应原致使患者的大小气道功能受限,职业性哮喘可呈速发相反应或迟发相反应。呈速发相反应患者的临床表现明显。     

Gender and snow crab occupational asthma in Newfoundland and Labrador, Canada

Fish and shellfish processing employs many thousands of people globally, with shellfish processing becoming more important in recent years. Shellfish processing is associated with multiple occupational health and safety (OHS) risks. Snow crab occupational asthma (OA) is work-related asthma associated with processing snow crab. We present a gender analysis of findings from a 3-year multifaceted study of snow crab OA in Newfoundland and Labrador, Canada. The study was carried out in four snow crab processing communities between 2001 and 2004. An anonymous survey questionnaire on knowledge, beliefs, and concerns related to processing snow crab administered to 158 workers attending community meetings at the start of the research found that women were significantly more likely than men to associate certain health problems, especially chest tightness, difficulty breathing, and cough, with crab processing (P<0.001). Worker health assessments carried out with 215 processing workers (187 current/28 former; 120 female/95 male) found that female participants were more likely to be diagnosed as almost certain/highly probable snow crab OA and allergy (P=0.001) and to be sensitized to snow crab (P=0.01) than male participants. Work histories from the health assessments were used to classify processing jobs as male or female. Allergen sampling (211 allergen samples: 115 area, 96 personal breathing zone) indicated that the plant areas where these male jobs were concentrated were associated with lower levels of aerosolized crab allergens (the agents responsible for OA to snow crab) than areas associated with female jobs. This difference was statistically significant in the two plants with poor ventilation (p<0.001 and P=0.017 for these plants). A gender analysis of work history data showed that female health assessment participants were likely to have worked longer processing snow crab than males (5 years versus 3.5 years, respectively). Cross-referencing of work history results with allergen sampling data for male and female job areas showed a gender difference in median cumulative exposures (duration of exposure x level of exposures) for health assessment participants. Health assessment participants with estimated higher median cumulative exposures were more likely to receive a diagnosis of almost certain/highly probable OA and allergy. Semistructured interviews with 27 health assessment participants (24 female/ 3 male) with a diagnosis of almost certain/highly probable or possible snow crab OA indicated that these workers can experience substantial quality of life impacts while working and that they seek to reduce the economic impact of their illness by remaining at their jobs as long as possible. Indications of selection bias and other study limitations point to the need for more research exploring the relationship between the gender division of labor and knowledge, beliefs, and concerns about snow crab processing, as well as gender differences in prevalence, quality of life, and socioeconomic impact.     

Historical perspectives in occupational medicine. Allergic asthma to Bacillus subtilis enzyme: A model for the effects of inhalable proteins

The passage of 24 years since the diagnosis of allergic asthma in heavily exposed workers and in a few consumers due to dusty enzyme preparations of Bacillus subtilis compounded with laundry powder makes it possible to review objectively the many problems it raised. It emphasizes the lessons to be learned, relevant to inhalable enzyme products and to other inhalable proteins in general. Occupational allergic respiratory diseases were little studied at the time and the enzyme problems stimulated interest in what has now become a well-established and important field of medicine involving not only protein allergens but low molecular weight chemicals as well.     

A new risk of occupational disease: allergic asthma and rhinoconjunctivitis in persons working with beneficial arthropods

Summary For some years, biological pest control has been re-evaluated as an alternative to the indiscriminate use of pesticides. The number of bio-factories in Europe has been constantly increasing and today more than 100 technicians work in mass rearing of arthropods. Seven cases of asthma and allergic rhinitis are reported in 13 workers engaged in the production of beneficial arthropods. The subjects suffered from attacks of asthma and rhinitis when they came into contact with eggs and scales or waste of Chrysoperla carnea, Leptinotarsa decemlineata, Ostrinia nubilalis and Ephestia kuehniella. These attacks occurred after an average exposure period of 18 months. A RAST test, prepared by Lofarma, was carried out on subjects' serum against the above-mentioned allergens and was positive in all symptomatic subjects (7 of 13) and negative in the others. This demonstrates IgE direct sensitization mediated by complete antigens.     

A new risk of occupational disease: allergic asthma and rhinoconjunctivitis in persons working with beneficial arthropods

Allergic asthma and rhinoconjunctivitis have been reported in workers who are constantly in close contact with arthropods during the course of breeding and research. We investigated a group of ten people working with beneficial arthropods in a bio-factory. The following tests were carried out: skin prick test with allergens present in the workplace, baseline pulmonary function test, aspecific bronchial provocation test with ultrasonically nebulized distilled water, and pulmonary function test after workplace exposure in two subjects. The results demonstrated a good correlation between skin prick test, previous RAST positive reactions, clinical symptoms, and exposure. Pulmonary function test after workplace exposure proved positive in one asthmatic subject and in one subject with rhinoconjunctivitis. It is concluded that the evidence supports the occupational nature of these allergic diseases and that there is a need for careful surveillance and environmental monitoring within the workplace.     

Fatal asthma from powdering shark cartilage and review of fatal occupational asthma literature

BACKGROUND: Work-related asthma (WRA) is the most common work-associated respiratory disease in developed countries. METHOD: We report shark cartilage dust as a new potential cause of occupational asthma (OA) in the context of other fatal OA case reports. RESULTS: A 38-year-old white male worked for 8 years in a facility which primarily granulated and powdered various plastics. Sixteen months prior to his death, the plant began grinding shark cartilage. After 10 months of exposure, he reported chest symptoms at work in association with exposure to shark cartilage dust and a physician diagnosed asthma. Six months later, he complained of shortness of breath at work and died from autopsy-confirmed asthma. The latency from onset of exposure to symptoms and from symptom onset to death was shorter than 10 previously reported OA fatalities. CONCLUSION: Recognition of occupational causes and triggers of asthma and removal of affected individuals from these exposures is critical and can prevent progression to irreversible or even fatal asthma.     

Occupational asthma due to chromium and nickel salts

Background: Exposure to chromium and nickel salts is a poorly characterized cause of occupational asthma. Methods: We describe four patients with work-related asthma due to metallic salts. Skin–prick tests to potassium dichromate and nickel sulfate were performed. The patients underwent methacholine inhalation tests and specific inhalation challenges (SIC) with both chromium and nickel salts. Results: Two patients showed positive skin–prick tests to potassium dichromate and nickel sulfate. All patients had bronchial hyperresponsiveness to methacholine, which increased 24 h after SIC with metallic salts. SIC with potassium dichromate elicited late asthmatic reactions (LAR) in two workers, one subject had an early asthmatic reaction (EAR), and another subject showed a dual asthmatic reaction (DAR). SIC with nickel sulfate induced a DAR in one subject and a late asthmatic reaction in another. Conclusions: Chromium and nickel salts can give rise to occupational asthma in exposed workers. The underlying mechanism may be IgE-mediated in some cases.     

Quality of life of adults with workplace exacerbation of asthma

Objective A cross-sectional study collecting demographic, work history, disease, and quality-of-life (QOL) data from adults with asthma was explored for a relationship between workplace exacerbation of asthma (WEA) and QOL. Study design and setting The study population of adults with asthma was drawn from adults affiliated with Fallon Community Health Plan, a health maintenance organization serving Massachusetts. Results The sample consisted of 598 adults with asthma. Based on univariate analyses, study participants with WEA had a statistically significant higher Total QOL score, indicating a worse quality of life, than participants whose asthma was not work-related (2.43 vs. 1.74, P ≤ 0.001), and also higher scores on the instrument’s four subscales for Breathlessness, Mood Disturbance, Social Disruptions, and Health Concerns. After controlling for covariates using multiple linear regression, the relationship between WEA and the Total QOL score was statistically significant (P = 0.0004) with a coefficient of 0.54. The coefficient for WEA was also statistically significant based on regression models for all the subscales with the exception of the Breathlessness score (P = 0.08). Conclusion In summary, WEA was associated with a worse QOL. Ideally, employees and employers would work together to minimize the conditions at work that contribute to WEA, which should decrease the frequency of WEA and related degradation of QOL. The U.S. Government's right to retain a non-exclusive, royalty-free license in and to any copyright is acknowledged.     

The prevention of mite‐allergic asthma

Asthma is common in day‐to‐day practice in most surgeries, yet GPs would have to content themselves with treating the symptoms and prescribing prophylactic drugs only. This paper tries to probe into the possibility for active prevention of asthma. House dust mites are now considered as one of the causal factors for allergic asthma. It is the commonest allergen encountered in the UK and since there is a constant exposure to these allergens, their avoidance if it is implemented methodically, may alter the prevalence of asthma as well as in the improvements of its symptoms. There are several well‐studied methods to avoid these allergens, but none of them would be effective when applied individually. A few measures will have to be integrated to combat the complex nature of this disease. These measures are not frequently implemented as there is no standard guideline and moreover, the results of clinical trials on these methods are often conflicting. However, it was found that when these measures are applied consistently for more than 6 months, all methods have proven to be effective. The authors have compiled a feasible approach to tackle this complicated problem.     

Comparison of six colour vision tests for occupational screening

Summary Screening of red-green colour vision defects was done for 52 school children (22 boys and 30 girls) and 231 trade school students (226 boys and 5 girls) with three different kinds of pseudo-isochromatic plates: Ishihara (1983), Boström-Kugelberg (1972), and Standard Pseudoisochromatic Plates part 1 (SPP1) 1978, and with three different kinds of vision screeners: Keystone View Model DVS 2, Bausch and Lomb Vision Tester, and Rodenstock Farbentestscheibe 3040.173. After these tests, each subject was examined with the Nagel Anomaloscope; this revealed 26 red-green defectives in the study group. Ishihara found 20/26 (76.9%), Boström-Kugelberg 24/26 (92.3%), and SPP1 17/26 (65.4%) of the defectives. None of the normals were diagnosed as defectives with Ishihara or SPP1. With Boström-Kugelberg four normals were diagnosed as defectives. Keystone found 24/26 (92.3%), Bausch and Lomb 26/26 (100%), and Rodenstock 25/26 (96.2%) of the defectives. But 9, 21, and 112 normals, respectively, were diagnosed as defective. In the present study, the Boström-Kugelberg and Ishihara plates as well as Keystone Vision Screener and Bausch and Lomb Vision tester came close to an effective screening test and could be recommended for screening red-green colour vision defects in occupational health care.     

Isocyanate exposure and occupational asthma: a case-referent study

OBJECTIVE—To examine the quantitative relation between exposure to isocyanates and occupational asthma, and to explore the role of atopy and smoking in occurrence of the disease.
METHOD—A case-referent study was undertaken of cases from two manufacturing companies (A and B) from which referents without disease could be selected and reliable exposure measurements were available. In company A, 27 cases mainly attributed to toluene diisocyanate (TDI) were matched to 51 referents on work area, start and duration of employment, sex, and age. Exposures were estimated from existing measurements by job category. In company B there were seven cases attributed to 4,4'-diphenylmethane diisocyanate (MDI) in two areas of the plant; 12 non-cases from the same areas were used as referents. Personal exposure measurements were available for all cases and 11 referents.
RESULTS—No difference in peak exposures between cases and referents was found in either plant; but in both, time weighted average (TWA) exposures at the time of onset of asthma were higher for cases. In A, the mean TWA exposure for cases was 1.5 (95% confidence interval (95% CI) 1.2 to 1.8) ppb compared with 1.2 (1.0 to 1.4) ppb for referents. From a matched analysis, the odds ratio (OR) associated with 8 hour TWA exposure to isocyanates greater than 1.125 ppb (the median concentration for the referent group) was 3.2 (95% CI 0.96 to 10.6; p=0.06). Occupational asthma was associated with a pre-employment history of atopic illness (OR 3.5, p=0.04) and, less strongly, with smoking (OR 2.1, p=0.14). In B, small numbers limited analysis, but three of seven cases had at least one TWA exposure measurement greater than 5 ppb compared with one of 11 referents (OR 7.5, p=0.09).
CONCLUSION—Asthma can occur at low concentrations of isocyanates, but even at low concentrations, the higher the exposure the greater the risk. By contrast with other studies, smoking and atopy seemed to increase the odds of occupational asthma due to isocyanates, but did not affect the estimate of risk associated with exposure.


Keywords: occupational asthma; isocyanates     

职业性哮喘318例职业特征分析

目的总结职业性哮喘的临床特征,为修订我国职业性哮喘的诊断标准提供依据。方法以＂职业性哮喘＂、＂职业性支气管哮喘＂、＂作业现场支气管激发试验＂作为关键词,检索国内职业性哮喘的病例报道,分析其一般资料、潜伏期、致喘物、临床变现和诊断方法等。结果共统计出公开发表的国内医学专业文献14篇,其中报告318例职业性哮喘,男女比例基本相近,平均发病年龄为38.0岁,潜伏期多为个2个月～19年,致喘物占前3位的分别为异氰酸酯类、青霉素和头孢菌素类、甲醛。在所有患者的诊断过程中,经作业现场支气管激发试验诊断为职业性哮喘152例,占48.8%,依据特异性IgE抗体诊断19例,依据特异性皮肤试验皮肤诊断仅1例。结论职业性哮喘的病因诊断并不容易,我国近半数患者经作业现场支气管激发试验诊断为职业性哮喘。如何认定职业接触与哮喘症状的发生发展存在关系,是我们需解决的主要问题之一。