Phthalate-free Plasticizers in PVC - Executive Summary
This Healthy Building Network (HBN) Research Brief examines replacements for phthalate plasticizers in Polyvinyl Chloride (PVC) building materials. Plasticizers are added to PVC to make it flexible, but since they are not tightly bound to the PVC molecules, they migrate from PVC products. Phthalates, the most commonly used plasticizers in PVC, are known endocrine disruptors – chemicals that interfere with hormone signaling, which is especially critical to early childhood development. Additionally, many phthalates are known carcinogens and reproductive and developmental toxicants. Exposures to these toxic plasticizers from PVC products can occur throughout their lifecycle. Therefore, it is crucial that PVC products containing phthalate plasticizers be eliminated from the built environment. In response to consumer and regulatory pressures, PVC building products manufacturers have begun to offer phthalate-free products. This research brief takes a detailed look at the six plasticizer alternatives now in use in PVC building products. It compares what is known and unknown about these substances’ human health and environmental impacts, and compares them to the known effects of a standard phthalate used in PVC building products, diisononyl phthalate (DINP). Key Findings HBN identified six phthalate-free plasticizer types, three synthetic and three bio-based, in use in commercial PVC building products. The available data suggest that non-phthalate plasticizers present fewer human health hazards than phthalates. This is not the same as saying that there are no health hazards associated with these non-phthalate plasticizers. It is important to remember that plasticizers – phthalates or not – will migrate from PVC products and building occupants will inevitably be exposed to them. However, some phthalate-free plasticizers raise fewer concerns than others. Our comprehensive review of available literature finds that:Phthalate-free Plasticizers in PVC | Healthy Building Network
Two bio-based products – Grindsted Soft-n-Safe (made by Danisco/DuPont) and Polysorb ID 37 (made by Roquette) are well studied and appear to be the least toxic of the six non-phthalate plasticizers reviewed. Di-(2-ethylhexyl) terephthalate (DEHT), sold by Eastman Chemical under the trade name Eastman 168, fares better than DINP in most health and environmental hazard endpoints. However, further study is needed due to uncertainties surrounding endocrine disruption and reproductive toxicity. GreenScreen hazard assessment gives Ecolibrium, a proprietary plasticizer made by Dow, a high score (3) when it does not contain antioxidants and a lower score (2) when it does. However, the GreenScreen methodology does not account for upstream (manufacturing) impacts. Dow’s decision to keep Ecolibrium’s ingredients secret makes it impossible to fully consider its impacts. Hexamoll DINCH (Diisononyl cyclohexane-1,2-dicarboxylate) also compares favorably overall to DINP, including for carcinogenicity and developmental toxicity. However, DINCH uses DINP in its manufacture and DINCH is less biodegradable and more persistent in the environment than DINP. Eastman Chemical’s dibenzoate plasticizers, sold under the Benzoflex trade name, compare well with DINP, but contain substances that are more ecotoxic and have the potential to bioaccumulate. Even without phthalate plasticizers, the lifecycle of PVC has inherent toxicities that cannot be avoided. At its core, PVC relies upon chlorine chemistry that forms toxic byproducts from its manufacture to its disposal. While the elimination of phthalate plasticizers from PVC does not these solve inherent problems, it does provide a specific relief to building occupants who are otherwise exposed through the everyday use of PVC products. To achieve flexibility without the use of these chemical additives, building material options other than PVC are available and should be prioritized for use over PVC.