Alternatives assessment involves a review of a current product and possible alternative chemistries or systems with the ultimate aim of reducing the product’s potential impacts on human health and the environment. Unlike a traditional product risk assessment, alternatives assessment considers not only hazard (i.e., toxicity) and exposure potential, but also the feasibility, performance, and cost of the current product and alternatives to obtain a comprehensive understanding of what a change in the product would mean. Notably, alternatives assessment considers these decision factors throughout the product life cycle, from raw material acquisition, product production, and product use, through product end of life.
Alternatives assessment can range from the fairly simple (e.g., an internal company discussion of whether a new product chemistry is worth pursuing) to the more complex (often in response to a regulatory requirement). Alternative assessment is also typically done in stages, as a way of maximizing information for decision-making while limiting time and cost.
Gradient scientists are well equipped to address green chemistry and alternatives assessment needs on many fronts, including helping companies make decisions about project formulation, chemical assessment and hazard ranking, regulatory support and review, risk screening and prioritization, and life-cycle thinking.
Alternatives Analysis of 6-PPD
On behalf of the US Tire Manufacturers Association, Gradient conducted a Preliminary Alternatives Analysis (AA) under California’s Safer Consumer Products (SCP) regulation for motor vehicle tires containing the antioxidant chemical 6-PPD. A degradation product of 6-PPD, 6-PPDQ, has been shown in laboratory studies to produce mortality in coho salmon. To explore possible 6PPD alternatives, we conducted an extensive AA evaluating the chemical hazard, exposure potential, and performance of 60 initial alternative antiozonants and identified 5 alternatives that would be suitable for analysis in a Stage 2 AA. The Preliminary AA was reviewed and accepted by California regulators.
Spray Foam Alternative Analysis
Gradient conducted an Alternatives Analysis under California’s Safer Consumer Products (SCP) regulations for methylene diphenyl diisocyanate (MDI) used in two-component, high- and low-pressure sprayed polyurethane foam. Alternatives evaluated included both different chemistries, as well as different application systems. We identified product requirements and functions, relevant toxicological, exposure, performance, and cost information, and compared alternatives with the designated priority product. We then developed an Abridged Alternative Assessment report for submission to state regulators. The report was subsequently approved by California’s Department of Toxic Substances Control (DTSC).
Alternative Assessment of Automotive Refrigerants
Gradient evaluated human health and environmental risks of potential alternative automotive refrigerants as compared to the predominant refrigerant, HFC-134a, which is being phased out to address climate change concerns. We used fault-tree analyses to perform an assessment of potential toxicity and flammability of the alternatives. We also evaluated relative costs, technical feasibility, and environmental impacts of HFC-134a and its alternatives.
Alternative Assessment of Biocides
Gradient evaluated potential replacement biocides used in the leather tanning process for a client concerned about potential for skin sensitization. The work was for internal product development purposes. We used the Interstate Chemicals Clearinghouse (IC2) Alternatives Assessment method to identify potential alternative chemicals that could be used. Our analysis aided our client in negotiating with suppliers over possible production changes for their products.
Comparative Alternative Assessment for Electronic Equipment
Gradient conducted a comparative evaluation of two dielectric fluids proposed for use in electric automotive vehicles. We created air models of potential passenger and repair worker exposures in the event of system failures and assessed the associated potential health risks of those exposures. Our work considered the technical performance of the two materials, as well as their life-cycle impact.
Health and Environmental Impact Evaluation of Polyvinyl Chloride (PVC) Alternatives
Gradient performed an evaluation of the human health and environmental impacts of commercial wall coverings for the developer of a commercial building. These included polyvinyl chloride (PVC)-based wall coverings, as well as those made of natural, fiber-based materials. The evaluation considered the impacts of the material choices across their full life cycle. Our work helped the developer make an informed selection of the wall-covering material.
