Fashion insiders are warning the great and the good of Hollywood not to wear sequins on the Academy Awards red carpet because of their terrible environmental impact.

Last Sunday at the Baftas, despite guests being urged to opt for more planet-friendly fashion choices, Scarlett Johansson wore a sequinned pink Versace dress, Rebel Wilson was wrapped in a red sequin custom-made Prabal Gurung gown and Naomie Harris shone in silver sequinned Michael Kors. At the Grammys and Golden Globes last month, the red carpets were similarly awash with sequins.

Facebook Twitter Pinterest Queen & Slim actor Jodie Turner-Smith in her canary-yellow sequinned Gucci gown. Photograph: Henry Nicholls/Reuters

Awards season is an opportunity for stars to send a message. Sustainable fashion consultant Alice Wilby would like to see a blanket ban on sequins and believes that if celebrities “really care about sustainability, they would stop wearing sequins on the red carpet”.

They “are made from toxic, petroleum-based plastics which pollute our living planet and persist for hundreds of years”, according to Leigh McAlea of Traid. “Like the fashion industry itself, sequins may be shiny on the outside but they hide serious socio-environmental impacts,” she said.

When they do start to break down, according to Lottie Hanson-Lowe, a creative partner at environmental charity Hubbub: “They become even smaller types of plastic – microfibres or even nanofibres. Those are a huge issue. Microfibres contribute to a third of microplastics pollution in our oceans,” she said.

Sequins also raise issues of working conditions and supply chain transparency. “Much finishing work is done by hand,” according to McAlea, “and factories often subcontract to homeworkers, typically women and child labourers, who are easily exploited.”

There are more sustainable versions available. According to Wilby, “recycled PET sequins and biodegradable options are being developed”. But, she said: “Unless we instantly replace all plastic sequin production with biodegradable options, the eco-version will still be inspiring people to buy the cheaper plastic version.”

While sequins on the high street might be more damaging in terms of scale, frequency of washing and lifespan, sequins on the red carpet send a strong message. “The ‘Red Carpet’ is a powerful platform. Our clothes speak volumes about who we are and what we stand for,” advised the Baftas’ sustainable dressing guide last weekend.

Livia Firth, founder of Eco Age, a sustainable fashion consultancy that is challenging celebrities to dress more sustainably via its Green Carpet Challenge, said: “Fashion has a huge power to change the world and it’s time for everyone to show how.”

As for any difference between the red carpet incarnations and those that are mass-produced, Wilby said: “Wearing a couture gown embellished with sequins that have been sewn by a seamstress who is well paid and well treated is no excuse,” she said, citing the impact on the trend-cycle. “It creates the desire for a raft of cheap, imitation dresses that will be worn a few times and then tossed. It’s time to stop.”