With further restrictions pending on phthalate plasticizers, including those used in medical applications, manufacturers of flexible PVC components should understand how the current and proposed regulations affect their materials.
Plasticizers are the key ingredient that makes flexible polyvinylchloride (PVC) able to bend without breaking or cracking so that it can be used in medical tubing and bags, squeezable toys, wire and cable, flooring, wallcoverings, and a myriad of other useful items.
Plasticizers can be made from different chemistries. Phthalate plasticizers—of which there are many different types—are the most widely used. In the past decade, various regulations have been enacted in the European Union (EU) and the US that limit the use of some ortho-phthalate plasticizers, due to concerns about potential negative effects on human health.
According to the American Chemistry Council (ACC), the extensive research on phthalates makes it one of the most well-characterized family of chemicals in use today.
This research shows that phthalates do not persist in the environment, and they do not bioaccumulate in living organisms;
(1) Most phthalates used today are not associated with endocrine effects, but some studies indicated that some ortho-phthalates might be endocrine disruptors (i.e., interfere with hormone production)
(2) Use of selected phthalate plasticisers has been restricted as a precaution by the regulations discussed in the following sections, and research is ongoing.
The EU’s REACH (Registration, Evaluation, Authorisation and Restriction of Chemicals) Regulation currently restricts use of several phthalate plasticizers. Two that had been widely used in flexible PVC but have been under the EUs authorisation scheme since the “sunset date” of February 2015 are DEHP and BBP (see Table for chemical names).
|Abbreviations for some phthalate plasticizers.
||butyl benzyl phthalate
These plasticizers can’t be used in the EU unless authorised by ECHA for a specific use, although they are still widely used in other regions of the world. The REACH Committee recently reconfirmed that the recycling of flexible PVC made with DEHP is authorized, noted the European Council for Plasticisers and Intermediates (3). These REACH restrictions do not apply to medical devices.
The EU’s Restriction of Hazardous Substances (RoHS) Directive, which came into effect prior to REACH, has regulated certain substances (e.g., lead) in electrical and electronic equipment since 2002. However, new substances are to be added to the RoHS list of restricted substances, including four phthalates (BBP, DEHP, DBP, and DIBP), effective in 2019.
Use of these phthalates in medical devices will be restricted as of 2021. Although DBP and DIBP are not used significantly in PVC, DEHP is widely used in medical devices, especially in the US. Materials used in medical devices must undergo extensive testing and approval.
CA Prop 65
The US state of California’s “Prop 65” (the Safe Drinking Water and Toxic Enforcement Act of 1986) is a list of chemicals that the state says can cause cancer or reproductive toxicity.
This list doesn’t restrict use of the materials, but requires businesses to “inform Californians about exposure to such chemicals” (4), typically through a warning label on a product. Because DEHP and some other phthalates are on this list, some companies are using or looking for alternative plasticizers.
The US Consumer Product Safety Improvement Act (CPSIA) of 2008 addresses various aspects of consumer products, particularly the safety of children’s products. In 2015, the US Congress permanently restricted the use of three types of phthalates (DEHP, DBP, and BBP) by banning any amount greater than 0.1% in children’s toys and “any child care article that is designed or intended by the manufacturer to facilitate sleep or the feeding of children age 3 and younger, or to help children age 3 and younger with sucking or teething”
(5) Congress has also placed an interim ban on DINP, DIDP, and DnOP in any amount greater than 0.1% in any children’s toys that can be placed in a child’s mouth as well as the articles described above for children 3 and under.
The EU has its own, similar, restrictions on phthalates in consumer and children’s products. DEHP, DBP, and BBP are banned for use over 0.1% in the EU in toys and childcare articles, and DINP, DIDP, and DnOP are prohibited only in toys and childcare articles that can be placed in the mouth.
Current proposals and potential regulations
Chemical regulations are continually being evaluated, and phthalates are still in the spotlight. For example, the US Environmental Protection Agency (EPA)’s Phthalates Action Plan from 2012 is investigating eight phthalates (DBP, DIBP, BBP, DnPP, DEHP, DnOP, DINP, and DIDP) (6).
In 2016, a coalition of NGOs submitted a petition to FDA requesting that FDA delist phthalates from food regulations; these substances would not be able to be used in any food-contact materials.
Although several of these products are no longer used commercially in the US, a few currently have important commercial uses, such as flexible medical compounds plasticized with DEHP. Many US manufacturing companies view “food contact” approval as an initial requirement for materials, whether or not their products are going into food packaging.
FDA is considering the petition according to the process required for doing so.
Suppliers of plasticizers for PVC have been working to develop acceptable alternatives to phthalate plasticizers, and there are several phthalate free chemistries commercially available. Some of these, such as citrates, have been in use for decades. Others, such as biobased plasticizers, are relatively new. Other nonphthalate classes include adipates, benzoates, trimellitates, and aliphatic esters.
Terephthalate chemistries, which have much different toxicological profiles than ortho-phthalates, are also an alternative. Different chemistries provide different performance properties that must be considered for a given use. For components that must be sterilized, for example, adipates resist gamma radiation, but citrates do not. PVC compound producers can give guidance on the best formula for a particular use.
1. ACC, Research-Phthalates accessed March 18, 2017.
2. ACC, Endocrine Studies, accessed March 18, 2017.
3. ECPI, THE PLASTICISERS INDUSTRY CALLS FOR REGULATORY PREDICTABILITY TO ENABLE PROTECTION OF CONSUMER HEALTH AS WELL AS COMPETITIVENESS AND GROWTH, March 5, 2017.
4. OEHHA, Safe Drinking Water and Toxic Enforcement Act of 1986, accessed March 18, 2017.
5. CPSC, Business-Guidance/ Phthalates-Information page updated July 7, 2015, accessed March 18, 2017.
6. EPA, Phthalates Action Plan1, March 14, 2012.