PVC additives

There are two main types of additives used with PVC:

Plasticisers are used if the PVC needs to be flexible.

Stabilisers are added to PVC to help during its processing and also to make it resistant to heat, sunlight and external forces.

 

Blood bags and medical tubing need to be flexible, so plasticisers are added to the PVC they are made from.

Plasticisers allow flexible PVC to be produced.
Picture: Norsk Hydro

Sustainable commitment

The PVC industry is committed to further research the risks associated with plasticisers and to look for alternatives if necessary.

Plasticisers

There has been concern over the use of phthalate plasticisers. Laboratory-based experiments in rats have shown that very high doses can cause cancers.

However, studies have shown that plasticisers do not cause problems at the levels that humans are typically exposed to.

The American Council on Science and health concluded that DEHP in medical devices was not harmful to even highly exposed people, such as those who undergo kidney dialysis or heart-lung bypass operations.

Stabilisers

Stabilisers can contain heavy metals such as cadmium or lead. These can be harmful if they accumulate in the environment. Calcium-Zinc compounds are used to give heat stability but these are regarded as safe.

Stabilisers help to protect window frames from damage by the ultraviolet radiation in sunlight.

Picture: Norsk Hydro

Sustainable commitment

Replacements for heavy metal stabilisers are being developed.
By 2010, the use of lead stabilisers will be cut by 50%. They will be completely phased-out by 2015.
Cadmium stabilisers are no longer used.