Increasingly, research studies revealed the harm caused by synthetic clothes shedding microplastic fibres, the petition said.
Those tiny plastic particles found their way into rivers and oceans, causing harm to marine life and subsequently to human health.
All garments shed microfibres during wear and washing.
The difference was that particles from natural fibres biodegraded while synthetic fibres did not.
Research showed synthetic microfibres accumulated in water and bound other toxic chemicals.
Plankton and fish often absorbed those microfibres and the toxic particles ended up in the food chain.
In California, a law that would make compulsory labelling of clothing items containing more than 50 per cent synthetic fibres was in the pipeline, while the state of New York had also presented a draft law which, if approved, would come into force in January 2021.
That proposal stated that no article of clothing containing more than 50 per cent of synthetic material could be sold without a specific information label which outlined the impact on the environment.
Schneider's petition, launched through the website www.change.org, attracted 10,000 signatures within two weeks.
Schneider has urged fellow members of the global executive committee of the International Wool Textile Organisation to act locally in their countries to get the law approved.
Last year, Smith was the first New Zealander to be appointed to the committee.
He has also been heavily involved with Campaign for Wool, a global endeavour initiated by Prince Charles to raise awareness of the benefits of the fibre.
Yesterday, Smith said he would do everything he could to get the proposal into law in New Zealand.
"I've taken it on my shoulders to champion the cause [here]", he said.
After meeting O'Connor, the next step was to work with the Ministry for Primary Industries to progress the proposal.
Until Smith saw what was involved with the process to get it into law, he did not know how long that was likely to take.
