Traditionally, lead-based compounds have been used in many parts of the world to stabilise rigid PVC for the construction industry use (e.g. pipes, fittings and profiles applications) and in flexible PVC, mainly for wires and cables.
Lead-based stabilisers’ cost/performance ratio and physical properties, in terms of excellent heat and light stability, good electrical resistance, excellent short and long-term mechanical properties and low water absorption, have made them the materials of choice for many long life applications.
Types of lead stabilisers are tetra-basic lead sulphate, tri-basic lead sulphate, di-basic lead phosphite, di-basic lead phthalate, di-basic lead stearate, neutral lead stearate.
Concerns have been expressed about possible adverse effects of lead on health and the environment. A full Risk Assessment on lead was conducted in 2004 and results were presented to the EU Authorities.
In the VinylPlus Voluntary Commitment, ESPA and EuPC (European Plastics Converters) committed to replacing lead stabilisers completely by the end of 2015 on the EU-15, with interim targets of a 15% reduction by 2005 and a 50% reduction by 2010. The commitment of 100% phase-out by the end of 2015 was extended to the EU-27 in 2007. The progressive substitution of lead-based stabilisers is ongoing and confirmed by the corresponding growth in calcium-based stabilisers, used as an alternative to lead-based stabilisers, more and more also outside Europe.
LIBRE (Lead In Blood REduction Programme)
An initiative from ELSA to foster good practices to promote blood-lead reduction
Risk Assessment on lead:conclusions
The Voluntary Risk Assessment on Lead was funded by the lead industry and managed by ILA Europe, the International Lead Association. ELSA (European Lead Stabilisers Association - a sub-group of ESPA) contributed for the stabilisers.
The studies indicated as early as 2005 that the DNEL (Derived No-Effect level) for blood lead was:
1) 40 µg Pb / dL blood for male worker
2) 30 µg Pb / dL blood for women of non-reproductive age
3) 10 µg Pb / dL blood for women of reproductive age to ensure protection of the unborn child
Those values were lower than most national limits in force at that time.
LIBRE: the response by the stabilisers manufacturers
ELSA aknowledged the DNEL derived from the Risk Assessment and the need to reduce exposure to lead. The association launched the LIBRE programme in May 2005. ELSA involved the Downstream Users (DU) associations through the EuPC structure. Gradually the manufacturers and the downstream users of lead compounds managed to reduce the exposure in their plants below the DNEL.
REACH Registration and Exposure Scenario
The DNEL derived from the Voluntary Risk Assessment were used for the REACH registrations. As a consequence, they have to be observed by the Downstream Users (DU) through the Exposure Scenario. In addition the national limits remain applicable, eg. the lead-in-air limits.
Good practices suggestions in the lead industry
The lower the better: lead is under continuous regulatory pressure. Therefore ELSA wishes to share with all DU the set of Recommended Good Practices established by the lead industry.