Eco-friendly and sustainable beauty is a complicated and nuanced topic—one in which there's no singular, "perfect" approach. However, it's a topic that holds tremendous urgency. As we all embrace the day-to-day opportunities of living a more conscious life, the beauty industry must make strides toward a more sustainable future for us all. And one in which we can enjoy the beauty of the world around us. 

As someone who spends a lot of time learning about the latest innovations in the industry, certainly there's progress to be celebrated. For example, ingredient selection, harvesting practices, and ethical sourcing have become top of mind for a wide variety of brands. Many have adopted better practices, such as opting for synthetic over natural when it involves a scarce resource or using wild harvesting and regenerative farming techniques to better replenish the land. 

Of course, packaging material is always part of the conversation as brands figure out how we can all move away from virgin plastics to more sustainable materials like PCR, glass, aluminum, and papers. Finally, the consumer is also being more thoughtful about their approaches to beauty: Gone are the days of bloated routines and consumption in excess—the chic routines are now thoughtfully edited. 

Those are the highlights. There are also areas we should spend more time finding solutions for. Namely, a formula's biodegradability. Just because you wash something away doesn't mean it disappears. It was a lesson learned through microplastic beads (a primary microplastic, meaning it's a plastic intentionally added to a product). They were once popular additions to face scrubs that have since been phased out as they can build up and pollute the water supply.

But they aren't the only ingredients that have the potential to wreak havoc on the waterways. There are still ingredients that show up in wash-off products, such as shampoos and cleansers, which inflict damage on our ecosystems. Additionally, "long-lasting" beauty products, such as makeups, occlusive balms, and hairstyling products, contribute as well.

There are three that eco-advocates warn most about:

So those are the primary offenders—now allow us to explain what happens after they circle the drain. Or rather allow Patrick Foley, Ph.D., founder and chief innovation officer of the cosmetic innovators P2 Science, to explain. He says that "when everything goes right, this is what it looks like: After it goes down the drain, if the ingredient is not biodegradable, it will eventually travel to a water treatment plant where it's filtered and digested by activated sludge treatment, activated carbon, or some other filtration method. This is what happens in many places across the country." 

But it's not the case for everyone, nor in all parts of the world. "If you don't have a water treatment facility as part of this process—[such as if you live in areas of the country or world] that has a septic tank, or there's no facility at the end of the line—all this is released into the environment," he says. Additionally, even if you do have a treatment plant, not all of these ingredients are adequately caught in the process depending on how modern the filtration system is.

So what happens, according to Foley, if an ingredient isn't biodegradable, "These start to accumulate in places they shouldn't be—and affect the water, amphibious life, insects, and so on." 

The fix to this is to use readily biodegradable ingredients. But even the term "biodegradable" comes with contention. "Right now in the cosmetic industry biodegradability is not regulated, so it's up to a brand's interpretation of what that means for them—is it five years? 10? A few weeks? And in what conditions can the ingredient break down? Unfortunately, there's no standard methodology for testing or defining the term right now," says clean cosmetic chemist Krupa Koestline, founder of KKT Consulting, in this episode of Clean Beauty School. 

Essentially, Koestline warns, the stage is set for a new branch of greenwashing. This, of course, doesn't mean that brands who tout the use of biodegradable ingredients should be an automatic red flag—however, just be mindful that "biodegradable" joins the ranks of "clean" and "natural" in that there are no defined criteria for its use. "Even if something takes 100 years to biodegrade, technically you can still call it biodegradable, but I would not call it biodegradable at that point," she says. 

If a brand says they use biodegradable ingredients in their formulas, see if they offer any more information—look for keywords like "readily biodegradable," "ultimate biodegradation," or even provide an amount of time that it can degrade under natural conditions. 

And while formula biodegradability hasn't entered the cultural zeitgeist in the same way as sourcing practices or packaging materials, some brands have thankfully started to pivot before there's public pressure to do so. Take Unilever, for example. The brand (who to their credit is pretty regularly at the forefront of sustainability initiatives) announced that by 2030, all the ingredients they use in their products will biodegrade completely and quickly (they note that for them "quickly" means within hours, days, or a few weeks at most). Of course, I must say: Many natural, clean, and indie brands have long been using biodegradable ingredients—without advertising it. 

But there are still brands that use these ingredients in products, from face cleansers to body options to shampoos. If you want to limit your use in the meantime, look for products free of silicones (especially cyclic-silicones), petrochemical polymers, and PFAS. Clearly, work is needed. 

The afterlife of your beauty products isn't just about the packaging, it's the ingredient afterlife too. "This is a fundamental ethical question that everyone who is developing a new product or ingredient must ask themselves before putting it out into the world," says Foley. As we move forward toward a more conscious industry, we need to think about the effects of our formulas—not just for the sake of our skin but for the environment that the formulas enter back into.