Use of clinical data in identification of respiratory sensitisers
Background
There has been a propensity by regulators to rely primarily on health surveillance/clinical case study data (case reports, clinical databases, worker exposure studies) to classify substances as respiratory sensitisers. The ECHA risk assessment committee (RAC) has for the first time made a harmonised classification and labelling (CLH) proposal to classify a chemical as a respiratory sensitiser based upon national surveillance data and the presence of the late asthmatic response (LAR) in specific inhalation challenge (SIC) tests. If successful this will lead to listing under Article 57(f) of REACH and addition to the candidate list for the SVHCs requiring restriction over the next 1+ years.
There is a need to evaluate the types of clinical methods and data sources used, and the implications of relying on such data for regulatory decision making from a scientific perspective.
Task Force objective
To date health surveillance and clinical case study data has been used in the clinical context for the management of occupational asthma (OA) where limitations in its predictive value are considered acceptable. The objective is to review the state of knowledge with respect to the value of such data, and to identify both the strengths and limitations of such data, if used in the context of chemical regulations, and potential areas for further research.
The following Terms of Reference have been defined:
- Based on a review of the relevant literature, summarise the current knowledge on the methods used for collecting, storing and analysing health surveillance data on occupational asthma across the EU (and UK), its predictive value in identifying respiratory sensitisers.
- Based on a review of the relevant literature, summarise the current knowledge on the available immunological/clinical data, including responses obtained in Specific Inhalation Challenge (SIC) tests for distinguishing irritant from immune responses and for predicting causation.
- Conclude on whether the available clinical methods and data can be regarded to be regarded as sufficient to justify classification as a respiratory sensitiser under REACH.
- Identify areas where further research might be beneficial in this regard.
Task Force deliverables
The Task Force published their findings and recommendations in the journal Critical Reviews in Toxicology: Scheel et al., 2025.