Restrictive lists like the Living Building Challenge’s “Red List” and the European Union’s Substances of Very High Concern are helping builders identify—and eliminate—hazardous materials from the product stream. But that is only half of the detoxification process. In order to truly achieve sustainable materials management, builders need to be sure that their alternative materials are, in fact, safer alternatives.

The challenge is that governing and authoritative bodies don’t assess benign chemicals, nor do they favor one chemical over another, which makes it difficult for project teams to specify replacements that are less hazardous than the original. Way too often, replacements end up being just as hazardous as the original—a frustrating and often expensive outcome.

Enter the GreenScreen tool from Clean Production Action (CPA). Unlike restrictive lists, which only identify chemicals of concern, GreenScreen applies benchmarks that rank chemicals from least hazardous (Benchmark 4) to most hazardous (Benchmark 1). You can see a diagram of the benchmarks here.

GreenScreen is based on the EPA’s Design for the Environment (DfE) criteria and evaluates 18 hazard endpoints that cover environmental fate, environmental health, human health, and physical hazards. According to Lauren Heine, CPA’s consulting co-director and director of the GreenScreen Program, it is important to note that the tool goes beyond hazardous lists and considers all hazard information, including current research. “The things you see on the lists are just part of the story,” Heine says. “A new chemical may not be on a list because it hasn’t been studied well enough to be classified yet. So it’s very important to not only look at lists, but to look at the scientific literature and toxicology literature so that you get a more comprehensive view.”

According to Nadav Malin, president of BuildingGreen and Vision 2020 chair, the challenge with this type of tool is finding a way for the industry to use it as an authoritative reference while it is changing dynamically. “Project teams need a fixed list to work from—they can’t be expected to update their specs throughout the design and construction process in response to continuously changing lists,” Malin says. “Some kind of versioning or date-stamping seems necessary, which is not something that GreenScreen does now.” (The GreenScreen version number addresses which lists it includes, but not all those lists maintain versions that keep track of which chemicals they include.)

Heine agrees that this certainly something that needs to be considered moving forward. She also thinks it will be important for GreenScreen assessments to be repeated at least every three years in order to take into account new research and advancing science. “Formaldehyde is not likely to not become a carcinogen any time soon, but there are several chemicals in which we are using limited data to make classification,” she says.

There are also other changes in the works. CPA is working on creating a repository of completed GreenScreen assessments, which could help procurement teams streamline their decisions. “CPA will keep a registry of validated assessments, but we will not necessarily create a database that contains GreenScreen assessments,” Heine clarifies. “We will partner with other organizations who wish to publish GreenScreen results. I would estimate that there will be pockets of assessments published within the year either on websites, databases, or as part of industry consortia to evaluate alternatives.”

A validation program is also being developed and will be piloted over the next six to 12 months, according to Heine. Currently, companies are not allowed to make promotional claims on products using the GreenScreen. The reports can be shared freely between companies and within their supply chain, but they cannot be used for marketing purposes.

Once a validation program is in place, Heine expects it to provide two benefits. “For purchasers, it will increase confidence in the results of a GreenScreen assessment, which is important because selecting materials in the supply chain is a big investment that is made carefully,” she says. “For manufacturers and formulators, validation will allow them to make promotional claims about the inherent hazard properties of their materials, which may lead to market advantages for products that are inherently more benign.”

In an ideal world, Heine would love to see the whole system automated. “Wouldn’t that be nice, to be able to put in an identified chemical and have it search and pop out a GreenScreen assessment?” she says. However, once again, the dynamics of this ever-evolving tool make it difficult for that to happen. “You can automate with a list, but you can’t do that with the literature review,” Heine notes.

The CPA has, however, created a separate resource called the GreenScreen List Translator, which maps out or “screens” chemicals that have appeared on different hazardous chemical lists. The List Translator has been built into two software tools—HBN’s Pharos tool and a new tool from The Wercs.

With HBN’s Pharos tool, a user could enter a CAS registry number, and the software will indicate if that chemical is a Benchmark 1 or possible Benchmark 1 chemical (based on lists only). “That’s pretty useful,” Heine notes. “You might get a result where you don’t know what the Benchmark score is, and that means it’s not on any hazard list that would identify it as a Benchmark 1.”

The Wercs tool is still under development, but Heine says it can give users almost instant information. Called GreenScreen Lite GreenWERCS, the software platform allows users to put in an unlimited number of chemical names, and the software will search about 850 sources of information to create a hazard table. If users want to do a full assessment, they can fill in the data gaps with research.

Heine says both tools are really helpful for identifying chemicals of concern or identifying that a chemical is possibly not a chemical of concern because it hasn’t been identified as hazardous by any authoritative body. However, she adds that they are both limited in scope compared to a full GreenScreen assessment.

Looking ahead, Heine envisions GreenScreen being specified in broader eco standards and scorecards. “It’s really a piece of the puzzle,” she says. “It’s not an ecolabel in its own right. It’s something that can be built into other systems.” The tool has already received mention in draft versions of LEED v4 and the Health Product Declaration (HPD). Of course, only time will tell if it will be specified in the final versions and whether or not those specifications will be referring to full GreenScreen assessments or only the GreenScreen List Translator.

Either way, Heine says the goal is to see hazardous assessments like the GreenScreen help move product design, development, and procurement toward more sustainable material flows. “I think one day, this will just be one of the questions all procurement and product developers ask,” she notes. “As a procurement officer, you will be able to say, ‘We want to be buying products that are Benchmark 2 or higher,’ or a product engineer can go and look for flame retardants that are Benchmark 3 or higher—without being experts in toxicology.”