How chemicals are assessed

Last update 30 November 2016

The Inventory Multi-tiered Assessment and Prioritisation (IMAP) framework is a science and risk based framework for the assessment and prioritisation of chemicals on the Australian Inventory of Chemical Substances (AICS).

Tools, criteria and international assessment approaches were considered during development of the IMAP framework with a focus on Canada, USA, Europe and international agencies such as the Organisation for Economic Co-operation and Development (OECD) and the World Health Organisation (WHO).

The framework aims to resolve the main issues raised by stakeholders which include information on exposure, reducing duplication by using information generated overseas and achieving assessment outcomes early in the program.

Key features of the framework are:

Figure 1

Diagram showing the IMAP Framework assessment process: from chemicals of low concern through Tier II and Tier III.

The IMAP framework consists of three tiers of assessment, with the assessment effort increasing with each tier.

Scientifically robust risk based approach

The framework uses simple and transparent criteria to determine the potential exposure and risks from chemicals to human health and the environment. The framework also allows for expert judgement, such as peer review to be applied where appropriate.

Achieving assessment outcomes early in the framework

This approach takes into account advice and requests from stakeholders, including industry and the community, to produce assessment outcomes early in the program and for each tier (see Figure 1). The effort and resources being used should match the potential risk of the chemical.

At each successive tier, the comprehensiveness (and hence resource intensiveness) of the assessments increases, while the number of chemicals requiring assessment decreases.

Using overseas data

A number of other countries and international agencies are generating or gathering information about the human health and environmental effects of a broad range of chemicals. To ensure efficiency and reduce duplication of effort, NICNAS is using this information (where appropriate) in the Australian context.

To maximise this information, the framework's human health and environmental scientific criteria are aligned with existing hazard classification frameworks already in use across industry and internationally.

Advancements in assessment methodologies

To ensure best practice in assessing chemicals in Australia, internationally recognised assessment tools are used to fill gaps in data on a number of human health and environmental hazard indicators.

Tools and approaches being used are Quantitative Structure Activity Relationship (QSAR) models or computational models for predicting toxicity and data from suitable analogue (similar) chemicals.

A flexible approach to exposure information (actual, surrogate or default)

The greatest challenge when assessing the risks of chemicals on AICS  is limited information on identity, volume and usage on chemicals currently being imported and/or manufactured in Australia.

The framework uses surrogate information to estimate exposure, such as from overseas sources, or conservative default values (where actual or surrogate information is not available) in the early stages (Tier I and Tier II assessments).