Our work
The use of toxicity data on a structurally-similar compound to evaluate a substance that has been inadequately tested – the so-called “read-across” approach – is a crucial part of the toxicologist’s skill set. Exploiting read-across can minimise the number of new tests conducted on vertebrate animals, while still ensuring that chemicals are safe for workers and the general population. We have been routinely using read-across in our hazard and risk assessments for many years, and have often incorporated it into the REACH regulatory submissions we have prepared.
Read-Across and REACH
Read-across is one of the key options described in the EU REACH regulation for deviating from the standard information requirements. ECHA have published guidance on using read-across in REACH dossiers, which sets out the standards that have to be met. We have extensive experience of drafting read-across justification reports to these requirements, including preparing a data matrix, and advising on potential in silico or in vitro testing that could be used to support a read-across strategy.
Approaches
There are two general approaches to read-across. In the first, data from a small number of “analogues” are used to fill data gaps in the target compound (by extrapolation). The other approach is the “category” approach, where a trend is predicted in a structurally-related group of substances. In this approach, data gaps are filled by interpolation.
Scenarios
ECHA guidance on read-across establishes a number of scenarios. In general, these can be divided into those where compounds are predicted to be transformed or broken down (e.g. by metabolism) to common compounds, and those where compounds are predicted to interact with the same biological target. We have a wide range of experience drafting read-across justifications for both of these scenarios.
Some of our case studies in this area
A human health risk assessment of API-related impurities
Case study
Whilst developing an inhalation spray drug product, the client identified two impurities with chemical structures related to the Active Pharmaceutical Ingredient (API). Click through to read more about how we dealt with this interesting project.
Human health risk assessment of unknown contamination
Case study
The client reported that small “brown spots” had been observed on the inside surface of a batch of aluminium tubes that contain a topical drug product. The source and chemical composition of the brown spots was unknown. Click through to read more about how we dealt with this interesting project.
Toxicological risk assessment of a disinfecting agent in a syringe medical device
Case study
The client manufactures a product which is used as part of a syringe line medical device. The connection set-up has the potential to introduce a disinfectant chemical into the line and be injected into patients. Click through to read more about how we dealt with this interesting project.
Some industries we work in
REACH
We are a leading supplier of REACH compliance services, assisting chemical manufacturers, importers and downstream users comply with their REACH Regulation responsibilities.
Pharmaceuticals
Our team is adept at preparing critical toxicological reports - we regularly provide assessments of novel or unexpected impurities, excipients and other intentionally-added substances, and extractables and leachables.
Extractables + Leachables
We provide valuable support to the pharmaceutical, medical device and processing equipment industries by producing screening reports and, if warranted, full risk assessment reports relating to extractables and leachables (E&L).
