Flexible friends
Stéphane Content, sector group manager of The European Council for Plasticisers and Intermediates (ECPI), discusses how plasticisers have been making PVC flexible for medical applications for decades
Perhaps because they are not the glossiest or the most celebrated of materials, recent evolutions in the plasticisers industry may have gone unnoticed in the medical sector. Items made of flexible PVC containing plasticisers are found in rooms and corridors of medical facilities all around the world. They are essential components of life-saving applications such as tubing, dialysis, endotracheal, feeding and pressure monitoring, catheters, blood and urine bags, gloves, mattress covers as well as flooring and wall coverings.
Medical PVC products were originally developed as replacements for natural rubber and glass. Their low cost, safety, high performance and versatility to manufacture single-use devices resulted in a revolution in the sixties. Today, almost 30% of all plastic-based pre-sterilised single-use medical applications used in hospitals are made from PVC.
Plasticisers in medical applications
In the medical world, the most commonly used plasticiser is di (2-ethylhexyl) phthalate, known as DEHP or DOP, which is commonly found in medical bags containing blood and other intravenous solutions. However, as regulatory, market pressure and controversy have been increasing around this plasticiser, a number of alternatives have been developed by the industry.
Substances used in medical devices are exempted from REACH authorisation for human health aspects although this may be about to change as the European Parliament is working on a revised Medical Devices Directive which may ban CMR and endocrine disrupting substances. A second vote is expected for the next parliamentary term after the European elections in May 2014. In addition, recycling of non-infectious DEHP-containing material could become more burdensome as there is no clarity if REACH authorisation or the EU waste regime is to be applied.
There are many other plasticisers employed in the PVC flooring and wall coverings installed in medical facilities. Those applications have the characteristic of an absence of joints that makes for a smooth continuous surface without any gaps where harmful bacteria, fungi or other pathogens thrive. This is a desired property in buildings requiring high levels of cleanliness such as hospitals and clinics but also in schools or sports centres.
European trends and developments
Phthalates – are the most commonly used plasticisers. They are broadly divided into two groups – high (HMW) and low (LMW) – according to their molecular weight. They have very different applications and legal EU classification.
Twelve LMW phthalates, classified as Category 1B reproductive agents have been identified as Substances of Very High Concern (SVHC) and placed on the REACH Candidate List. Four of these substances, DEHP, DBP, BBP and DIBP, are on the Authorisation List. This means that after February 2015, these four substances can be placed on the EU market only for those uses for which an authorisation has been granted to specific applicants.
Demand has been shifting away from LMW towards HMW which today represent around 85% of all phthalates being produced in Europe. At global level, the trend is quite different and DEHP still makes up for around 50% of all phthalates used worldwide. The market for alternatives to phthalates is fast developing all around the world.
Pioneering recycling
The majority of PVC medical devices are ‘single-use’ products. Medical waste is generally managed through incineration. However, recent experiences have shown that recycling of medical waste has the potential to be successfully implemented in healthcare settings like hospitals, contributing to smart use of resources and improved cost-efficiency. Currently, there is one project running in Australia where sorting and recycling systems are in use to recycle non-infectious hospital PVC waste.
In Europe, the PVC Industry runs the VinylPlus sustainability program, which has a strong focus on recycling. In 2013 alone, over 440,000 tonnes of PVC were recycled. The use of lead lead-based stabilisers in the EU-27registered a decrease of 81.4% compared to 2007 levels.
The future of plasticisers
The plasticisers’ manufacturers have been continuously investing to provide safe and reliable products which can satisfy the needs of tens of thousands of companies throughout the supply chain. Ensuring that the importance of plasticisers is well understood amongst all stakeholders remains a key challenge for the sector - in medical applications and beyond. The industry will continue working to provide the information needed by policy makers, regulators and users on the many benefits of using flexible PVC in order to cope with current and future challenges.