Harm reduction advocates say the state government's decision to destroy drugs ditched in amnesty bins at music festivals is a wasted opportunity to test the dangerous substances on the market.

The bins - announced late last year - have so far been used at eight NSW events deemed "high risk" by state authorities between December 31 and February 2, including major festivals such as Field Day and Laneway festival.

Drug amnesty bins were placed near the entry of Field Day music festival in the Domain on New Year's Day. Credit:James Alcock

A response to Deputy State Coroner Harriet Grahame's inquest into the deaths of six young people at NSW music festivals, Premier Gladys Berejiklian said the bins would allow punters to avoid panicking when they see police and dispose of their drugs "without any questions asked".

Ms Grahame said amnesty bins would also give authorities the chance to test the discarded substances and provide information to health providers. Results can also be used to send out real-time alerts to revellers about dangerous drugs that may be present at a music festival.