Director, Systox Ltd, Sutton, Cheshire, UK.
Faculty of Biology, Medicine and Health, University of Manchester, Manchester, UK.
Crit Rev Toxicol. 2022 Feb;52(2):139-166. doi: 10.1080/10408444.2022.2064267. Epub 2022 May 24.
Methyl methacrylate (MMA) is classified under GHS as a weak skin sensitiser and a skin and respiratory irritant. It has recently been proposed that MMA be classified as a respiratory sensitiser (a designation that in a regulatory context embraces both true respiratory allergens, as well as chemicals that cause asthma through non-immunological mechanisms). This proposal was based primarily upon the interpretation of human data. This review, and a detailed weight of evidence analysis, has led to another interpretation of these data. The conclusion drawn is that persuasive evidence consistent with the designation of MMA as a respiratory sensitiser is lacking. It is suggested that one reason for different interpretations of these data is that occupational asthma poses several challenges with respect to establishing causation. Among these is that it is difficult to distinguish between allergic asthma, non-allergic asthma, and work-related exacerbation of pre-existing asthma. Moreover, there is a lack of methods for the identification of true chemical respiratory allergens. The characterisation and causation of occupational asthma is consequently largely dependent upon interpretation of human data of various types. Recommendations are made that are designed to improve the utility and interpretation of human data for establishing causation in occupational asthma.
甲基丙烯酸甲酯（MMA）在 GHS 中被归类为弱皮肤致敏剂和皮肤及呼吸道刺激物。最近有人提议将 MMA 归类为呼吸道致敏剂（在法规背景下，这一指定涵盖了真正的呼吸道过敏原，以及通过非免疫机制引起哮喘的化学品）。这一建议主要基于对人类数据的解释。本综述以及详细的证据权重分析，导致了对这些数据的另一种解释。得出的结论是，缺乏与将 MMA 指定为呼吸道致敏剂相一致的令人信服的证据。有人认为，对这些数据有不同解释的原因之一是职业性哮喘在确定因果关系方面存在若干挑战。其中包括难以区分过敏性哮喘、非过敏性哮喘和与工作相关的原有哮喘恶化。此外，缺乏识别真正化学性呼吸道过敏原的方法。因此，职业性哮喘的特征和病因在很大程度上取决于对各种类型的人类数据的解释。提出了一些建议，旨在提高人类数据在确定职业性哮喘因果关系方面的实用性和解释性。
