What is CARS?

CARS is a decision support tool that uses a database of chemical information in conjunction with information on how the organization uses chemical products. The database includes well-documented and publicly available information on chemical aspects and their potential impacts on human health and safety, ecological health, and ecosystem-wide impacts. The CARS system provides a framework for assessing chemicals and setting goals for substitution or elimination of problematic materials or processes. CARS identifies hazard and other information, but it is not a risk assessment tool.

To date, the application of CARS has resulted in decisions to eliminate a number of hazardous materials in products and processes — at a wastewater treatment plant, at the Oregon State printing facility, in Multnomah County, and at manufacturing businesses. See more project summaries.

How Does CARS Work?

The CARS inventory process is designed to put in direct view of decision-makers the information needed to make decisions that will lead to a more benign chemical inventory and operations. The ranking of chemicals requires both judgment and sound information. CARS accepts a listing of chemicals by CAS number and provides a set of results flags identifying carcinogens, suspected carcinogens, teratogens, persistent bioaccumulative toxins, global warming gasses, ozone depleting chemicals and more. This information may then be used along with the values of the organization to identify relative rankings to create a prioritized list. One organization used this to identify lists of the “Big Five” and the “Dirty Dozen”, referring to the five products used in the greatest amounts and the twelve products determined to contain the most hazardous ingredients.

To reduce the impacts of chemical use, organizations may simply choose a high-use toxic chemical and start an improvement project. More ideally, however, they may implement a change program that includes an inventory, assessment, and ranking of the products to prioritize the most significant potential impacts, followed by goal-setting, implementing improvements and reviewing and reporting results. These results will show reduced risks and (usually) cost savings.

The CARS program is designed to support the first three steps of the change program. Generally, it is difficult to assess chemical products because they usually contain multiple ingredients with diverse human and environmental health impacts. The CARS process provides structure for performing the inventory, assessing the chemical impacts and supports the process of prioritization. The beauty of the CARS approach is that it pulls together peer reviewed and reputable information on chemical hazards in a way that supports decision-making based on the organization's values.

Once products are targeted for replacement or elimination, the organization generally identifies an individual or team to carry out research and find alternatives. The Zero Waste Alliance can provide support in this process through the application of green chemistry principles or by providing links to outside resources. For example, there are a growing number of manufacturer/formulators who are developing green cleaning product lines that may provide appropriate alternatives. The ZWA can provide referrals to these alternative vendors and will run the alternative formulations through the CARS database if desired.

CARS relies on Chemical Abstract Service (CAS) numbers that can be found on Material Safety Data Sheets (MSDSs) for chemical products. However, MSDSs come in all types of formats — some more informative than others. Because MSDSs are primarily created for safety reasons, often they are lacking full chemical ingredient disclosure. Some may not list any CAS numbers at all. In these cases it may be necessary to contact the product manufacturer to identify the chemical ingredients. CARS can work without full ingredient disclosure but it is most useful when the CAS numbers for all ingredients are listed on the MSDS. Confidentiality agreements with manufacturers can help obtain CAS numbers. In these cases, percent compositions can be omitted entirely, if necessary.

CARS data and sources

CARS data includes: From sources such as:

How does CARS support Environmental Management Systems?

CARS is based on the same see-think-plan-do cycle that is used by formal environmental management systems and may be used to help make them more effective. We've seen that integrating CARS into the aspects and impacts analysis improves the decision-making process of selecting significant aspects. This can also result in more effective selection of objectives and targets, and strengthen programs or projects that are chosen for implementation.

What CARS is not

CARS is not a risk assessment model that tries to put a risk value on your products or processes. Risk assessment involves judgments that are not transparent and may not be equally important to different organizations. For example, one company may be particularly concerned about worker health while another may be concerned about discharge to local streams.