The Facts about PVC Stabilisers

As the UK’s largest manufacturers of calcium organic stabilised PVC-UE building products, I feel it’s partly our responsibility to try to clarify to your readers at least one of these challenges - The facts about the latest environmental and legislative developments as they affect PVC stabilisers; especially as there appears to be some misunderstanding circulating in the market! I understand how the combination of technical minutiae and jargon associated with European Directives isn’t the most immediately inspiring subject, but it is nonetheless critical that as an industry we understand the implications of the current and planned developments to protect and future proof our businesses.

Current Drivers for Change - Vinyl 2010, The Marketing and Use Directive 76/769 EEC and REACH.

Vinyl 2010 is the European PVC industry’s 10-year Voluntary Commitment for sustainable development and product stewardship across the life cycle of PVC. The Voluntary Commitment was set up in 2000 to minimise the environmental impact of PVC production, promote responsible use of additives, support collection and recycling schemes, and encourage social dialogue between all of the industry’s stakeholders. There are a number of commitments against each of these criteria (www.vinyl2010.org), the main one related to stabilisers being a reduction in lead stabiliser consumption from 2000 levels by 15%, 50% and finally 100% by 2005, 2010 and 2015, respectively.

In 2008, European Stabiliser Producers Association (ESPA) members were able to report that lead stabiliser use in the EU-15 had reduced by over 50% since 2000, some two years ahead of the 2010 interim target. ESPA also reported that this reduction has been achieved through a switch to calcium-based (i.e. calcium organic) stabilisers (Vinyl 2010 Progress Report 2009 – Page 6).

No targets for Tin or calcium organic stabilisers are included in Vinyl 2010.

The Marketing and Use Directive 76/769 EEC - As we have been advising the industry for some time, under this Directive, DiButyl Tin (DBT) stabilisers of the type used by a number of PVC-UE profile manufacturers will be banned in articles for supply to the general public containing greater than 0.1% by weight of tin by January 1st 2012, or by derogation in some applications by January 1st 2015. In practice it is by no means clear if all roofline, cladding and window trim products fit in the former or the latter of these bans. For example, product used as a window board would appear to be banned by January 1st 2012, whereas the same product used as a replacement fascia may be subject to the derogation.

DiOctyl Tins (DOT) stabilisers of the type some producers claim to be using to replace DBT, at least in the cellular core, are also subject to restrictions under Directive 76/769 EEC. After 1st January 2012, these too will be banned from certain products that come into contact with skin, including childcare articles and wall coverings and this could include cladding.

One thing is certain, calcium organic stabilisers are not subject to any restrictions under Directive 76/769 EEC and a guaranteed way of avoiding any potential issues is to use this type of stabiliser. Choosing DiOctyl Tin stabilisers as a replacement for DiButyl Tin stabilisers may be a case of out of the frying pan...

REACH - (Registration, Evaluation and Authorisation of CHemicals) - Is the EU regulatory framework for the management and control of chemicals. This is a huge undertaking managed by the European Chemicals Agency (ECHA) and prioritises the process by a combination of volume and potential risk (highest volume and risk first). The exact outcome of the REACH process for each and every chemical manufactured and used in Europe is not known in advance. However, there is an increasing understanding of the likely outcome in many cases.

Since DBT is Category II (i.e. likely to be of risk to humans) Carcinogenic, Mutagenic or Reprotoxic (CMR) a registration document must be presented to ECHA by the end of November 2010. The production of this document, which includes a safety report, is an expensive process. Hence, in light of the deadlines in Directive 76/769 EEC and the volumes involved, it may not make commercial sense for companies to register these products. Thus the combination of REACH and Directive 76/769 EEC mean that most, if not all, of these stabilisers may not be able to be manufactured after November 2010, irrespective of these sunset dates.

Lead stabilisers (Category I CMR) also require a registration document by the end of November 2010. In this case a combination of existing safety reports and higher volumes mean that it is likely to make commercial sense for companies to register the main lead stabilisers. Currently it appears that the Industry’s voluntary commitment on lead (Vinyl 2010) and the progress made to date in reducing the consumption thereof, is such that the sunset date for lead stabilisers under REACH is likely to be around 2015, and therefore in line with Vinyl 2010.

DOT stabilisers (Category III CMR) with production volumes greater than 1000 mtpa will also require a registration document by the end of November 2010. It is currently unlikely that these will be subject to authorisation under REACH.

The components that make up commercial calcium organic stabilisers are either exempt from REACH (See annex 4 and 5 of REACH) or are not likely to be considered Substances of Very High Concern (SVHC). Hence, calcium organic stabilisers are not likely to be subject to authorisation under REACH.

Why Calcium organic?

There are many different applications for rigid and flexible PVC and most stabiliser systems – including lead, tin and calcium organic - have been around for many years.

Traditionally in Europe calcium organic stabilisers have been used in applications such as food, medical and pharmaceutical packaging and bottles for mineral water. They are now the preferred choice for pipes and cables and, as lead replacement by calcium organic continues under Vinyl 2010, calcium organic stabilisers will also become the stabiliser of choice for profiles, including windows. It should be noted that some European window profile producers have based their production on calcium organic stabilisers for almost 20 years with excellent results and proven weathering performance. One of the issues with DOT stabilisers as a replacement for DBT in external applications is the relatively little experience and natural weathering data that exists on colourfastness of these products in external building products in the UK.

European production volumes of calcium organic stabilisers were slightly more than lead and five times that of Tin stabilisers in 2008 (See Vinyl 2010 Progress Report 2009 – Page 6 and 23) a position that is likely to continue to strengthen. Hence, calcium organic stabilisers are clearly now the main PVC stabiliser by volume in Europe and the stabiliser of choice for rigid PVC building products in general – A position that ensures all stabiliser producers will continue the development and further improvement of calcium organic stabilisers in the coming years.

Meeting Legislative commitments on stabilisers, whilst important, is only part of our industry’s approach to sustainable development under Vinyl 2010. Other important considerations are the consumption of energy, water and raw materials during manufacture and the ability to recycle post industrial and post consumer waste. Under these measures of sustainability, calcium organic stabilisers also performer well. Since, moving to calcium organic stabilisers our business has continuously reduced like-for-like resource consumption and we are confident that in this respect our process and product compares favourably with our competitors, irrespective of the stabiliser used.

In recent weeks, I have come across misinformation about the reprocessing attributes of calcium organic stabilised PVC. As with all PVC formulae and all stabiliser types, performance depends on the combination of correct processing and formulation, but when a manufacturer gets these right, the results are excellent. Since moving to calcium organic stabilisers we have successfully processed significant quantities of material with high quantities of rework in the core, and any scrap from this process has also been reprocessed at the same high level. We reprocess any scrap in-house and do not send any in-process scrap to landfill. The other significant environmental benefit of using calcium organic stabilisers in PVC, unlike for example lead or tin stabilised product, is that they don’t have adverse interactions with most, if not, all other formulae. So when mixed end-of-life post consumer waste starts to become more available in years to come, calcium organic will be the most flexible platform for recycling. This is one reason why we have recently partnered Recovinyl - a European funded initiative to promote the collection and recycling of post consumer waste - and aim to identify new sources of recyclate in the future.

To conclude, I urge caution in listening to manufacturers who seem to be confusing their own inability to make a transition to calcium organic with the general use of calcium organic by other manufacturers who have already successfully made the switch. To summarise, calcium organic stabilisers:

• Are not included in any restrictions or bans resulting from Directive 76/769 EEC
• Will be REACH compliant
• Are the major stabiliser by volume for PVC in Europe
• Are the major stabiliser in building products in Europe – a position that will only strengthen as the impact of Vinyl 2010 continues apace
• Can be successfully recycled forming a versatile platform for PVC waste recycling of all types in the future.
• Are an ever improving technology that helps future proof our industry

Anyone worried or unclear on any of the above is welcome to contact me directly for further information or clarification.

Yours sincerely

Dr Sean Cockett, Technical Director, Kestrel BCE