If you want to be considered really unfashionable, you can do one of three things: wear spray-on skinny jeans (so 2002), wear socks with dress shoes or drink water from a single-use plastic bottle.

With fashion already taking the ignominious title of "second-biggest polluting industry" (behind oil production), sustainability has become a big action point across the industry.

But beyond making leggings from recycled fishing nets and promulgating a conversation about smarter and more responsible consumption, there is a new intersection of fashion and the environment that came on to my radar recently: the high-fashion water bottle.

I'd seen them in my yoga class, quietly sitting off to the side of equally expensive mats, seemingly sneering at me: "I take hydration more seriously than you."

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Who knew performative hydration would become a thing? Answer: Virgil Abloh.

The Off-White and Louis Vuitton designer has teamed up with French water brand Evian and Matchesfashion.com to produce what can only be described as the most high-fashion water bottle on the market. When it was announced, there was an instant wait list of 4000 people. 

Since going on sale for £37 ($70) a pop on February 25, the first day of Paris Fashion Week, several colour ways have sold out.

For a long time, the worlds of beauty and wellness have been slowly merging. No-one knows this better than Marita Burke, creative director of the Mecca group of retail brands.

A few years ago, Mecca, through its "Trove" group of boutique products, introduced bkr (pronounced "beaker", as in "water beaker", geddit?) to its product range. So why was a make-up and skin-care store suddenly devoting shelf space to a drink bottle?

With fashion already taking the ignominious title of "second-biggest polluting industry" sustainability has become a big action point.

"Inner heath and taking care of your body is becoming an increasingly larger part of beauty," Burke says.

"We know that maintaining good levels of hydration helps keep skin glowing and in turn, allows your skin care and make-up to do their job. We also know our customers are seeking a chic alternative to disposable plastic water bottles and bkr delivers just that with their sleek and sophisticated range."

I chill harder than you party.

A post shared by bkr (@mybkr) on May 23, 2018 at 10:58am PDT

Costing AU$58 for a 500ml or AU$73 for a one litre, bkr bottles may be the gold standard in portable hydration stations. But does pricey necessarily equate to better performance? And what about hygiene?

Professor Stuart Khan, an expert in water quality from the faculty of engineering at UNSW, says sharing a bottle can pose a risk for bacterial transmission.

"If you're drinking out of your own bottle, then the risks, even over the long term, are very low," he says. "It's the least likely way you're going to come into contact with bacteria."

And while it's easy to scoff at fashion's apparent gullibility when it comes to overpriced items (Celine plastic shopping bag, anyone?), there is a positive environmental story to tell.

As we all know, plastic water bottles, as well as takeaway coffee cups, are among the biggest environmental demons, especially in the developing world where potable drinking water is in short supply.

evian is proud to be @nyfw 's hydration partner again this season. Spotted: @troprouge rocking her #evianxVirgilAbloh @somawater bottle from our debut collection with @VirgilAbloh. Available on @matchesfashion and @matches_man Full collection to be released soon stay tuned ! #evian #VirgilAbloh #NYFW

A post shared by evian (@evianwater) on Feb 12, 2019 at 10:19am PST

A post shared by Soma (@somawater) on Feb 22, 2019 at 3:29pm PST

Evian has committed to making all its water bottles from recycled plastic by 2025. But really, the only way to reduce the amount of plastic in the environment is to stop making it.

So in that sense, the rise of the glass or metal reusable water bottle should be celebrated. Although it's not necessary to spend a bomb to make an impact.