Toxicology

An understanding of hazards to human health is an essential requirement for REACH. The data are used to determine acceptable exposure levels for humans, which forms part of the Chemical Safety Assessment, and for Classification and Labelling purposes. We can help decipher the legislation, determine which toxicological studies are required and minimise overall costs.

A range of studies is required to investigate toxicity following acute, short term and chronic exposure. These data requirements are tiered based on tonnage bands. Data requirements for low tonnage substances are minimal but these increase considerably as tonnages increase. Depending on the tonnage band (and potential exposure) specialised studies may be needed to determine whether a chemical is carcinogenic, genotoxic, neurotoxic or causes effects on reproduction, or on the developing foetus. Most toxicology studies still require the use of animals and many are expensive. With this in mind, JSC can interpret the legislation and advise on alternative approaches such as read-across, the use of structure activity relationships, in vitro testing, and establish when waivers can be requested, thus reducing animal usage and cost.

JSC provides advice on the human relevance of toxicity results, the use of structure activity relationships to assess the toxicity of metabolites and also on dermal absorption data to represent human exposure. JSC understands when a study is needed and whether an in vivo or an in vitro study, or both, will be required to provide an acceptable exposure assessment.

JSC evaluates the complete toxicity database on a chemical and applies expert judgment to the selection of endpoints and Derived No Observed Adverse Effect Levels (DNELs) for use in risk assessment. JSC has considerable experience of this process and of justifying and defending endpoints with regulatory authorities.

The results of hazard studies, particularly those involving mutagenicity, carcinogenicity, reproduction or developmental effects, are used to decide classification by the European Chemicals Agency (ECHA). The classification assigned to a substance can affect authorisations, so it is important to obtain as favourable a classification as possible. JSC can advise clients on the likely outcome of ECHA evaluations and on testing and regulatory strategies, which can lead to improved classification.