The South African Bureau of Standards (SABS) announced last month that all locally manufactured polyvinyl chloride (PVC) pipes would have to be free of heavy metals by July 2015.
This announcement was warmly received by the South African Plastic Pipe Manufacturers Association (Sappma).

SABS certification Gauteng GM Sibongile Dhlamini stated that the SABS Standard Division technical committee had amended a series of standards to ensure that all heavy metal stabilisers were removed in the manufacturing of PVC pipes.

Local manufacturers have 24 months, as of October last year, to comply with the new (relevant) standard requirements. New permits will be issued once pipes bearing the SABS mark of quality are resubmitted for testing, which entails the performance testing of products in terms of South African National Standards, as well as toxicity testing and the effects on water quality.

“In the interests of the consumer and good business practice, the SABS strongly promotes the highest possible product quality standards and environment-friendly manufacturing processes and materials. We, therefore, urge companies to ensure they comply with the new standards and start removing heavy metals form their manufacturing process, if they have not yet done so,” Dhlamini stated.

Sappma chairperson Jan Venter said that heavy metals could constitute a health hazard or danger to the environment, particularly persons who had been in prolonged contact with heavy metals.

“Heavy metals are used to stabilise PVC against heat and ultraviolet degradation. Without stabilisers, PVC cannot be processed successfully. Heavy metals will now be replaced by nontoxic stabilisers, which do not contain heavy metals. The most common alternatives are based on calcium soaps and organic substances,” he explained.

To ensure that the new standard is adhered to, manufacturers will have to undertake intensive trials to find the optimum dosage levels and to determine optimum processing conditions prior to production.

Venter noted that manufacturers would also have to test their products during and after production to ensure that there were no negative effects on the performance of the product, owing to the change in stabilisers.

He stated that responsible manufacturers cared for the environment and for the health and safety of their workers.

“This means that there is no option but to remove heavy-metal stabilisers from products. This will enhance the reputation of PVC as a safe and green material. Further, it is in line with the worldwide trend. This, in turn, means that local manufacturers will not only comply with international regulations but will also be able to sell their products internationally,” Venter enthused.

Heavy metal pollution is an environmental concern, and the toxicity and effects of certain heavy metals on human and animal health were being widely documented, he stated.

He noted that substances used in heavy metal stabilisers, such as lead, cadmium, barium and tin, were harmful, and even lethal, to humans and animals.

Venter added that Sappma had been undertaking the voluntary removal of heavy metal stabilisers from PVC pipes since 2006.

This move, which took into account the product’s end-of-life issues and waste management options, has added value to Sappma’s life-cycle thinking.

He explained that Sappma’s decision to undertake this voluntary removal, at considerable costs to Sappma members, was based on health and environmental considerations.