Andrew D. Curran

Standards of care for occupational asthma

Occupational asthma remains a common disease in the UK with up to 3000 new cases diagnosed each year. The Health and Safety Executive (HSE) estimates the cost to our society to be over £1.1 billion for each 10-year period.1 In October 2001 the Health and Safety Commission agreed a package of measures aimed at reducing the incidence of asthma caused by exposure to substances in the workplace by 30% by 2010. Key to this aim are primary prevention by proper risk assessment and exposure control, together with secondary prevention to ensure reduction in the delay between the development of allergic symptoms at work (normally nasal or respiratory) and appropriate advice to the affected worker and workplace. Conservative estimates suggest that one in 10 cases of adult onset asthma relate directly to sensitisation in the workplace,2 with a smaller subset of workers with acute irritant induced asthma. The latter—formerly termed reactive airway dysfunction syndrome (RADS)—relates to asthma caused by exposure to high levels of airborne irritants. The prognosis of individuals with occupational asthma is better if they are removed from exposure quickly, particularly within a year of first symptoms.3–5 However, removing individuals often leads to unemployment. If the diagnosis of occupational asthma is incorrect, advising individuals whose asthma is not caused by work to be removed from exposure may have unnecessary financial and social consequences. The intent of this article is not to document the entire current evidence base related to occupational asthma, as the British Occupational Health Research Foundation (BOHRF) recently completed such an evidence review.7 The key points of this article are summarised in box …

Standards of care for occupational asthma: an update

Background The British Thoracic Society (BTS) Standards of Care (SoC) Committee produced a standard of care for occupational asthma (OA) in 2008, based on a systematic evidence review performed in 2004 by the British Occupational Health Research Foundation (BOHRF). Methods BOHRF updated the evidence base from 2004–2009 in 2010. Results This article summarises the changes in evidence and is aimed at physicians, nurses and other healthcare professionals in primary and secondary care, occupational health and public health and at employers, workers and their health, safety and other representatives. Conclusions Various recommendations and evidence ratings have changed in the management of asthma that may have an occupational cause.

Sensitization to wheat flour and enzymes and associated respiratory symptoms in British bakers

RATIONALE Current literature suggests that flour exposed workers continue to be at risk of allergic sensitization to flour dust and respiratory ill health. OBJECTIVES A cross-sectional study of 225 workers currently potentially exposed to flour dust in British bakeries was performed to identify predictors of sensitization to wheat flour and enzymes. RESULTS Work-related nasal irritation was the most commonly reported symptom (28.9%) followed by eye irritation (13.3%) and work-related cough or chest tightness (both 10.2%). Work-related chest tightness was significantly associated (OR 7.9, 1.3-46.0) with co-sensitization to wheat flour and any added enzyme. Working at a bakery with inadequate control measures was not a risk factor for reporting work-related respiratory symptoms (OR 1.3, 0.4-3.7). Fifty-one workers were atopic and 23 (14%) were sensitized to workplace allergens. Atopy was the strongest predictive factor (OR 18.4, 5.3-64.3) determining sensitization. Current versus never smoking (OR 4.7, 1.1-20.8) was a significant risk factor for sensitization to wheat flour or enzymes in atopic workers only, corrected for current level and duration of exposure. This effect was not seen in non-atopic workers (OR 1.9, 0.2-17.9). Evidence of sensitization to less commonly encountered allergens was also seen to Aspergillus niger derived cellulase, hemicellulase and xylanase mix, in addition to glucose oxidase and amyloglucosidase mix. CONCLUSIONS The combination of health surveillance and exposure control in this population has been insufficient to prevent clinically significant workplace sensitization. Smoking may pose an additional risk factor for sensitization in atopic workers. Am. J. Ind. Med. 52:133-140, 2009.

Job Categories and Their Effect on Exposure to Fungal Alpha-Amylase and Inhalable Dust in the U.K. Baking Industry

Enzymes in flour improver, in particular fungal alpha-amylase, are known to be a significant cause of respiratory allergy in the baking industry. This study measured total inhalable dust and fungal alpha-amylase exposures in U.K. bakeries, mills, and a flour improver production and packing facility and determined whether assignment of job description could identify individuals with the highest exposures to fungal alpha-amylase and inhalable dust. A total of 117 personal samples were taken for workers in 19 bakeries, 2 mills, and a flour improver production and packing facility and were analyzed using a monoclonal based immunoassay. Occupational hygiene surveys were undertaken for each site to assign job description and identify individuals who worked directly with flour improvers. Analysis of exposure data identified that mixers and weighers from large bakeries had the highest exposures to both inhalable dust and fungal alpha-amylase among the different categories of bakery workers (p<.01). Currently, the maximum exposure limit for flour dust in the United Kingdom is 10 mg/m(3) (8-hour time-weighted average reference period). In this study 25% of the total dust results for bakers exceeded 10 mg/m(3), and interestingly, 63% of the individuals with exposure levels exceeding 10 mg/m(3) were weighers and mixers. Individuals who worked directly with flour improvers were exposed to higher levels of both inhalable dust and fungal alpha-amylase (p<.01) than those who were not directly handling these products. Before sensitive immunoassays were utilized for the detection of specific inhalable allergens, gravimetric analysis was often used as a surrogate. There was a weak relationship between inhalable dust and fungal alpha-amylase exposures; however, inhalable dust levels could not be used to predict amylase exposures, which highlights the importance of measuring both inhalable dust and fungal alpha-amylase exposures.

Occupational Asthma. An assessment of diagnostic agreement between physicians.

Objectives: To investigate the levels of agreement between expert respiratory physicians when making a diagnosis of occupational asthma. Methods: 19 cases of possible occupational asthma were identified as part of a larger national observational cohort. A case summary for each case was then circulated to 12 physicians, asking for a percentage likelihood, from the supplied information, that this case represented occupational asthma. The resulting probabilities were then compared between physicians using Spearman’s rank correlation and Cohen’s κ coefficients. Results: Agreement between the 12 physicians for all 19 cases was generally good as assessed by Spearman’s rank correlation. For all 66 physician–physician interactions, 45 were found to correlate significantly at the 5% level. The agreement assessed by κ analysis was more variable, with a median κ value of 0.26, (range –0.2 to +0.76), although 7 of the physicians agreed significantly (p<0.05) with ⩾5 of their colleagues. Only in one case did the responses for probability of occupational asthma all exceed the “on balance” 50% threshold, although 12 of the 19 cases had an interquartile range of probabilities not including 50%, implying “on balance” agreement. The median probability values for each physician (all assessing the identical 19 cases) varied from 20% to 70%. Factors associated with a high probability rating were the presence of a positive serial peak expiratory flow Occupation Asthma SYStem (OASYS)-2 chart, and both the presence of bronchial hyper-reactivity and significant change in reactivity between periods of work and rest. Conclusions: Despite the importance of the diagnosis of occupational asthma and reasonable physician agreement, certain variations in diagnostic assessment were seen between UK expert centres when assessing paper cases of possible occupational asthma. Although this may in part reflect the absence of a normal clinical consultation, a more unified national approach to these patients is required.

Management of occupational health risks in small-animal veterinary practices

BACKGROUND Small-animal work is a major element of veterinary practice in the UK and may be hazardous, with high levels of work-related injuries and ill-health reported in Australia and USA. There are no studies addressing the management of occupational health risks arising from small-animal work in the UK. AIMS To investigate the sources of health and safety information used and how health and safety and 12 specific occupational health risks are managed by practices. METHODS A cross-sectional postal survey of all small-animal veterinary practices in Hampshire. A response was mandatory as this was a Health & Safety Executive (HSE) inspection activity. RESULTS A total of 118 (100%) practices responded of which 93 were eligible for inclusion. Of these, 99 and 86%, respectively, were aware of the Royal College of Veterinary Surgeons (RCVS) practice standards and had British Small Animal Veterinary Association (BSAVA) staff members, while only 51% had previous contact with HSE (publications, advice and visit). Ninety per cent had health and safety policies, but only 31% had trained responsible staff in health and safety. Specific health hazards such as occupational allergens and computer use were relatively overlooked both by practices and the RCVS/BSAVA guidance available in 2002. CONCLUSIONS Failings in active health risk management systems could be due to a lack of training to ensure competence in those with responsibilities. Practices rely on guidance produced by their professional bodies. Current RCVS guidance, available since 2005, has remedied some previous omissions, but further improvements are recommended.

Climate change: enabling a better working Britain for the next 100 years

Climate change is one of the most pressing issues facing the global community and has the potential to impact on the environment, society and global economy. The evidence of observed increases in ambient temperatures (‘global warming’) is strong and the frequency of extreme weather events over recent decades has also increased [1]. Although there is still debate over the effects of human impact on global climate change [2], efforts to mitigate the extent of observed changes have been extensive. Despite this, it is predicted that this trend is likely to continue and the impact will be broad and complex, resulting in a need for human and environmental adaptation, which will have far reaching consequences on all facets of life and work. While initiatives and strategies to promote effective adaptationtoclimatechangeanditsassociatedeffectsarenow inprogress,understanding the impactofclimatechangeon workers’ health and safety has seen little research and remains largely unknown. As a consequence, the potential impact for occupational health specialists is not clear. To date, most of the climate change research has focused on public health as opposed to occupational health (and safety) outcomes. This is in part due to lack of useful data relevant to this relatively new component of occupational health and safety research. A framework has been devised to help identify the possible impact of climate change on the workplace and workers and consequently occupational morbidity and mortality [3]. The hazards identified were grouped into seven main categories with possible exposures and related health effects:

Immunologic response to inhaled endotoxin: changes in peripheral cell surface markers in normal individuals.

Monocyte cell surface CD14 increases following both in vitro challenge with lipopolysaccharide (LPS) and exposure to organic dusts. We investigated 9 volunteers, mean age 39 years (range, 29–53 years). Each inhaled increasing concentrations of lipopolysaccharide (0.5 μg, 5.0 μg, and 20 μg). Monocyte cell surface CD14 (expressed as mean linear fluorescence) was measured before and after using flow cytometry. Upregulation of CD14 (up to 6 hours after LPS exposure) did not differ significantly between LPS (mean, 35.8; standard deviation [SD]; 54.3), n = 7 after 20l g LPS) in comparison to placebo (39.3 [49.0]; n = 7). Maximum mean (SD) percentage CD14 upregulation up to 6 hours after challenge differed, but not significantly between those experiencing a clinically significant event (58.4 [49.2]) in comparison to those who did not (13.8, [43.2]; P = 0.27). Two individuals with a marked clinical response developed marked CD14 upregulation after exposure to LPS.

From cotton mills to composites; has the world of work really changed?

The last two hundred years has witnessed a remarkable transformation in the world of work. In the early 19th century, the industrial revolution introduced the ability to mechanise processes previously performed by people. As a consequence, workplaces became larger and more complicated. Change was not limited to the physical nature of the workplace: workers were also required to work differently, and interact with work in different ways. Work became more organised, ordered and systematic. Many of these changes brought about the transformation of not only the workplace, but also the working population and the economic prosperity of some parts of the world.

Enabling a better working Britain: celebrating the centenary of the Health and Safety Laboratory

On 3 May 1911, Mr Enoch Edwards MP (member of parliament for Hanley) enquired what arrangements were being made to continue experiments with coal dusts that had previously been funded by coal owners and others at Altofts colliery in West Riding. In response, the Secretary of State for the Home Department, Mr Winston Spencer Churchill, replied, ‘This matter has been receiving the careful consideration of my right hon. Friend the Chancellor of the Exchequer, and myself, and I am glad now to be able to state that it has been decided to continue these experiments under the supervision of the Home Office, and that the Treasury have sanctioned the considerable expenditure that will be necessary for the purpose’ [1]. With these words, Winston Churchill established the Home Office Experimental Station at Eskmeals in Cumberland, the organization now known as the Health and Safety Laboratory (HSL), and transferred the funding of research into the safety of coal mines from the private to the public sector. At that time, a number of underpinning principles were established that have stood the test of time. Specifically, the research station was established as a national asset for the UK; the focus was on the development of practical solutions to workplace health and safety problems; that these problems were best solved by multidisciplinary teams and that the knowledge generated should be transferred to those who need it. One hundred years later, those principals still hold good, even though the organization and the world in which it operates has significantly changed. At the time of HSL’s foundation, 1000 people died every year as a result of underground accidents in coal mines [2], and many more died as a result of the health consequences of working with coal. In those early days, the majority of the work carried out by the laboratory centred on coal dust explosions, but the effects of coal and other dust exposures on health were also considered. Indeed, in the very first report of the Explosions in Mines Committee (under whose auspices the experimental work was performed), they presented work by Dr Beattie from Sheffield University regarding the potential health consequences that could arise from the addition of stone and other incombustible dusts to the miners’ working environment to prevent explosions [3]. The first Director of the new government-funded facility was Dr R. V. Wheeler, who worked closely with Dr Marie Stopes on the physical and chemical properties of coal. In 1918, they published a monograph entitled ‘The Constitution of Coal’, published in 1918 by the Department of Scientific and Industrial Research [4]. It was a comprehensive review of the subject and indicated many areas for future advance. Around this time, Dr Wheeler wrote to Marie Stopes saying, ‘I received a slight thrill reading that you have dissolved coal’. She responded by sending him a copy of her book on ‘Married Love’ also published in 1918 [5]. Over the years, HSL has evolved as its operating context changed, be it political, social or economic. The first major change came in 1920, when it was agreed that the facilities in Eskmeals had deteriorated as a result of the First World War, while problems in the industry had steadily accumulated which required urgent solutions. A new location was sought, and a new body, The Safety in Mines Research Board, was appointed to oversee the development of a new research facility. Part of the specification included the requirement that the site ‘must not be near any working coal mine’, so as not to alarm local residents when experimental explosions were undertaken. In January 1924, a site near Buxton was identified and £500 000 ( £16.4M today) was provided to establish the facility. The official opening of the site by The Viscount Chelmsford (Chairman of the Miner’s Welfare Committee) took place in June 1927. The Buxton site focused on large-scale experimental explosions of coal dust and firedamp, experiments with gob fires and mining explosives and other work, which, as the programme to commemorate the opening event stated, ‘owing to its character can only be conducted in a position of comparative isolation’. A further site was opened in Sheffield in 1928 by the Prime Minister, Stanley Baldwin, which undertook work on the constitution of coal, the safe use of electricity in mines and on the improvement of the miners’ safety lamp. Staff from the two sites worked as one unit, and the broad range of disciplines meant that more complex problems could be investigated. Indeed, it was recorded in a report describing the research activities undertaken, that, ‘The work of research now is less often within the capacity of one man than it was when Davy invented a safety lamp after a few weeks’ work’ [6]. Throughout the 1930s and 1940s, the work in both the Sheffield and Buxton facilities became more sophisticated and included increasing work on health-related issues. As a consequence, the international reputation of the facility grew, and in 1931, the First International Conference of Safety in Mines Research Institute was held at the Buxton facility; this conference continues to this day, and the international mining community will celebrate the 80th anniversary of this prestigious global conference in India in 2011. During the 1930s, the Buxton site also hosted