The US EPA has outlined a set of goals and objectives for its strategic plan to promote the development and implementation of alternative tests methods, as part of the amended toxic substances control act (TSCA).
Its focus is on risk-based decision making, said Gino Scarano from the EPA, at a public meeting co-organised by the Interagency Coordinating Committee on the Validation of Alternative Methods (Iccvam). He described the opportunities for using new approach methodologies (NAMs) as "huge".
The EPA has been tasked with developing a plan for using alternative methods for TSCA testing by June 2018. The agency has outlined six goals, which match statutory requirements set out in TSCA legislation. They are to:
- promote the development and implementation of alternative test methods and strategies;
- ensure that the strategic plan is reflected in the development of requirements for testing;
- list particular alternative test methods or strategies;
- develop criteria for scientific reliability and relevance of test methods and strategies;
- submit a progress report to Congress every five years; and
- prioritise and carry out performance assessment, validation and translational studies to accelerate the development of alternative methods/strategies.
For each goal, the EPA is also developing different sets of near, mid- and long-term objectives for new and existing chemicals. For example, the agency plans to use NAMs as a first-tier screen for new chemicals by 2022. From that date, it also hopes to use alternative test methods for quantitative or qualitative risk evaluation.
"For existing chemicals, there is a very large effort to prioritise the 80,000-odd chemicals on the inventory, to determine which ones to focus on for risk evaluation," said Dr Scarano.
"Prioritisation is where we see the key point of using existing NAMS," he said. "On the road, as we do the risk evaluation, find data gaps or have some concerns, we will be asking for NAMs to fill those gaps."
Dr Scarano also described a need to collate data on the most requested current alternative test methods. "We think that it will be important to know what we have so that we can build a better way in future of figuring out what we need the most," he said.
He highlighted Iccvam's new approach to alternative testing, as outlined in its draft roadmap. This takes a "top-down" approach to testing, with regulators guiding new test development based on their needs.
It is vital to understand which information regulators require and its "context of use", said Warren Casey, director of the US National Toxicology Program's Interagency Center for the Evaluation of Alternative Toxicological Methods (NICEATM), which provides scientific and operational support for Iccvam.
"We have methods on the books that are technically validated but have never once been used," said Dr Casey. "When they were validated, people didn't understand what agencies or industry needed… We can't just focus on a set of regulations. We actually have to figure out how the agencies and industry are using that information," he told the public meeting.
"Anybody that is in this business knows that we need to change the standard approach to validation that we have used in the past. We need to make it more efficient, we need to make it faster, cheaper and we need to end up with a method that people are going to use," he concluded.
Speaking at the meeting, Rick Becker from the American Chemistry Council pointed out that the risk-based approach means that it will be necessary to work out how to integrate exposure into alternative testing approaches.
At each node, there is an opportunity to consider exposure as part of your decision context. Rick Becker, ACC
"At each node, there is an opportunity to consider exposure as part of your decision context. That is going to be a challenge but also an opportunity to bring exposure science and approaches into the programme," he said.
New chemicals have specific testing needs, he added. "We just say: here's a new assessment method. Without the specifics of how it can fit within a particular regulatory decision context, it is going to be really hard for people to use those and we will run into challenges with acceptance and use."
The EPA's Office of Pesticide Programs (OPP), the Office of Research and Development (ORD), the Office of Science Coordination and Policy (OSCP), and the Office of Pollution Prevention and Toxics (OPPT) are all involved in developing the strategic plan.