A descriptive study of occupational asthma due to acrylic compounds - study protocol. REC reference 16/YH/0308
A descriptive study of occupational asthma due to acrylic compounds
Dr Gareth Walters – Chief Investigator;
Dr Vicky Moore – Collaborator.
Acrylates (acrylic monomers) are esters of acrylic acid, which readily polymerise to form plastics known as ‘acrylics’ or ‘poly-acrylates’. These are used variously in industry as adhesive resins, surface coatings, synthetic textiles, chemical intermediates and hard plastics. Methacrylates, of which the most commonly produced is methyl methacrylate, are used in the manufacture of poly methyl methacrylate (PMMA) hard plastic, commonly seen in the UK as transparent plastic glass (Perspex, Plexiglas). Methyl methacrylate is also encountered in orthopaedic prostheses, sculptured artificial nails, dental fillers and orthopaedic bone cement. Cyanoacrylates are chemically distinct from other acrylates and methacrylates, and readily polymerise in the presence of small quantities of water or humid air, and form a strong bond between various materials. Cyanoacrylates have been produced commercially since the 1950s as instant glues (Loctite Superglue) and surgical tissue adhesives.
Acrylic compounds and allergic disease
Acrylates and their derivatives have been described as causes of occupational contact (skin) hypersensitivity (Calnan, 1979; Wrangsjo et al., 2001) and allergic rhinitis (Savonius et al., 1993), and a small number of case series of occupational asthma due to sensitization to acrylates have also been reported (Lozewicz et al., 1985; Savonius et al., 1993; Quirce et al., 2001; Sauni et al., 2008). The mechanisms by which acrylates cause occupational asthma remain largely unknown.
To describe the occupational exposures and worker characteristics associated with asthma caused by sensitization to acrylic compounds at work, in the West Midlands, UK, in order to provide insight into pathophysiology of this disease.
Heart of England NHS Foundation Trust is a core reporter to the ‘Surveillance of Work-Related and Occupational Respiratory Disease (SWORD)’ UK voluntary surveillance scheme for occupational respiratory disease, sponsored by the UK Health and Safety Executive (HSE) and hosted by the University of Manchester, UK (McDonald et al., 2005). Dr Gareth Walters sends monthly anonymised reports of newly diagnosed occupational respiratory diseases, including occupational asthma, to the scheme’s co-ordinator. No patient identifying details are included on the report.
Since 2002 all new cases of occupational respiratory disease diagnosed at the Heart of England NHS Foundation Trust occupational lung disease centre, have been recorded on a clinical database, comprising PID (Trust personal identification number), postcode, date of birth, date of diagnosis, name of occupational respiratory disease, causative agent(s), occupation, industry, and date of onset of symptoms. The database is saved on a password-protected hard-drive to which only attending clinicians have access to. Monthly anonymised reports to SWORD are collated using this database. We intend to identify all cases of occupational asthma due to acrylic compounds that have been notified by our institution to SWORD since 2002, by searching this database. We estimate that there will be 20 cases of occupational asthma due to acrylic compounds. Case finding will be done by Gareth Walters and Vicky Moore, by using the search terms ‘acrylate’ and ‘acrylic’.
For each patient identified, we will review the electronic and paper medical records to gather the following data: demographics (age, gender, ethnicity, co-morbidity, atopy, smoking status), occupation, employment duration, asthma symptoms at diagnosis, and work effect will be gathered, along with details of diagnostic tests: (i) skin-prick allergy testing (SPT) to common aeroallergens, (ii) serum total IgE (kU/L), (iii) two-hourly peak expiratory flow measurements analyzed using Occupational Asthma SYStem (OASYS; Gannon et al., 1996), (iv) non-specific bronchial hyper-responsiveness to methacholine challenge (NSBR) tested using the Yan method (Yan et al., 1983), (v) spirometry measured according to European Respiratory Society/American Thoracic Society (ERS/ATS) standards using European Community for Coal and Steel predicted values (Quanjer et al. 1993), and (vi) specific inhalational challenge (SIC) tests to controls and to acrylic compounds. The data will be anonymised (eg. ‘patient 1’, ‘patient 2’) and recorded in a separate Microsoft excel spreadsheet on the same password-protected hard-drive.
Descriptive statistics will be used to illustrate the characteristics of the workers, and display evidence for sensitization to acrylic compounds. Parametric data will be displayed using means and standard deviation, non-parametric data using median and inter-quartile range (IQR) and categorical data using percentages. All descriptive statistical analysis will be undertaken at the 95% confidence level using S.P.S.S. version 21.0 (IBM, New York, U.S.). No further analysis is intended.
There will be no funding for this study, as no additional costs have been identified. It will be undertaken by Gareth Walters and Vicky Moore as part of their roles at the NHS regional occupational lung disease centre at Birmingham Chest Clinic, Great Charles Street, Birmingham, UK.
The timescale for this study is 3 months.
Calnan CD. Cyanoacrylate dermatitis. Contact dermatitis 1979;5:165-7.
Gannon PF, Newton DT, Belcher J, Pantin CF, Burge PS. Development of OASYS-2: a system for the analysis of serial measurement of peak expiratory flow in workers with suspected occupational asthma. Thorax 1996;51:484–9.
Lozewicz S, Davison AG, Hopkirk A, Burge PS, Boldy DA, Riordan JF, McGivern DV, Platts BW, Davies D, Newman Taylor AJ. Occupational asthma due to methyl methacrylate and cyanoacrylates. Thorax. 1985;40(11):836-9.
McDonald JC, Chen Y, Zekveld C et al. Incidence by occupation and industry of acute work related respiratory diseases in the UK, 1992-2001. Occup Environ Med 2005;62(12):836-42.
Quanjer PH, Tammeling GJ, Cotes JE, Pedersen OF, Peslin R, Yernault JC. Lung volumes and forced ventilatory flows. Report Working Party Standardization of Lung Function Tests, European Community for Steel and Coal. Official Statement of the European Respiratory Society. Eur Respir J Suppl 1993;16:5–40.
Quirce S, Baeza ML, Tornero P, Blasco A, Barranco R, Sastre J. Occupational asthma caused by exposure to cyanoacrylate. Allergy 2001;56(5):446-9.
Sauni R1, Kauppi P, Alanko K, Henriks-Eckerman ML, Tuppurainen M, Hannu T. Occupational asthma caused by sculptured nails containing methacrylates. Am J Ind Med 2008;51(12):968-74.
Savonius B, Keskinen H, Tuppurainen M, Kanerva L. Occupational respiratory disease caused by acrylates. Clin Exp Allergy 1993;23(5):416-24.
Walters GI, Kirkham A, McGrath EE, Moore VC, Robertson AS, Burge PS. Twenty years of SHIELD: decreasing incidence of occupational asthma in the West Midlands, UK? Occup Environ Med 2015; 72(4):304-10.
Wrangsjo K, Swartling C, Meding B. Occupational dermatitis in dental personnel: contact dermatitis with special reference to (meth)acrylates in 174 patients. Contact Dermatitis 2001;45:158-63.
Yan K, Salome C, Woolcock AJ. Rapid method for measurement of bronchial responsiveness. Thorax 1983;38:760–5.
Please sign in or register to add your thoughts.