The Zero Discharge of Hazardous Chemicals (ZDHC) group is calling for the development of a single, unified discharge guideline and standardised analytical methods for monitoring wastewater quality in the textile industry. 

A review carried out by ZDHC of wastewater discharge guidance in the textile industry found a wide range of discharge regulations and measuring methods that differ from nation to nation, between guidelines published by brands and amongst multi-brand consortia. 

The group, which is working towards the zero discharge of hazardous chemicals in the apparel and footwear supply chain, suggests that developing a single, unified discharge guideline and standardised analytical methods for monitoring wastewater quality would benefit the textile industry greatly and drive momentum towards meeting the programme's zero discharge goal.

"To support industry-wide wastewater treatment guidance, the ZDHC programme has added the development of a unified wastewater discharge quality guideline as a new area of focus," said executive director Frank Michel. "Whilst working towards zero discharge of hazardous chemicals in wastewater will require continued collaboration between all parts of the global textile supply chain, a unified approach can further align the industry's shared commitment to improve human health and the environment."

According to the report, in total, 17 regulations were found covering 13 countries. Honduras was the only country researched that did not have regulations in place regarding industrial wastewater effluent. Of the 17 regulations, ten are specific to, or have a few parameter limits, that explicitly apply to the textile industry.

The report noted: "Though a few multi-brand consortia have worked towards developing industry wastewater guidelines, in recent years this engagement appears to have lost energy. In fact, guidelines developed in the past are now lagging behind current government regulations. This offers a unique opportunity to reinvigorate the topic."

The ZDHC programme will work with key collaborators to formulate a discharge guideline that will update widely used wastewater quality guidelines. These will focus on both ZDHC MRSL-listed chemical substances and conventional wastewater parameters to reduce or eliminate the risk of releasing MRSL-banned substances. 

"A stepwise approach begins with adoption of the ZDHC Manufacturing Restricted Substances List (MRSL) to control chemical input," the group noted. "The ZDHC Environmental Audit is an important second step to ensure processes are controlled properly, followed by effluent discharge controls to ensure our desired goal of zero discharge."

ZDHC recently updated its MRSL list to include leather. The MRSL Version 1.1 was developed by members of the ZDHC programme – which include Adidas Group, Benetton Group, C&A, Gap Inc, H&M, Inditex, Levi Strauss & Co, M&S, Nike Inc and PVH Corp – in close collaboration with third-party technical experts and global industry associations.

ZDHC group updates MRSL to include leather