Youthful Skin Comes at Cost to Ocean Food Web

Time to eliminate plastic micro-bead exfoliants
The beauty industry hits hard on the importance of frequent exfoliation to keep skin looking younger and healthy. Spherical plastic micro-bead scrubbers, no larger than a half millimeter, have been introduced into hundreds of skin care products in recent decades, but scientists are discovering that the ocean food web, and maybe human health, could be imperiled as a result.

As babies, skin cells are replaced every two weeks, but by age 50 the turnover rate has slowed to six weeks or longer, fostering wrinkles and other unwelcome signs of aging. Products containing plastic micro-beads profess to speed up cell rejuvenation, and their popularity signals that consumers have bought into the promise of exfoliating your way to a more youthful look. Whether or not such products deliver on this promise, scientists have discovered that these innocent-looking plastic micro-beads are insidious little transporters of chemical pollutants into lakes, streams and oceans and maybe onto our dinner plates.

Micro-beads are usually made of polyethylene (PE) or polypropylene (PP), and like other plastics, they’re thought to persist in the environment for a hundred years or more. They’re added to facial scrubs, body washes, soap bars, toothpastes and even sunscreens and designed to be washed down the drain. However, micro-beads commonly escape waste treatment plants and pollute bodies of water, because the plants aren’t designed to eliminate them or because wastewater is diverted directly to local waterways in heavier rains.

“Microplastics” are defined as plastic debris smaller than five millimeters and include both manufactured micro-beads and the breakdown products of larger plastic waste which fragments into progressively smaller bits during exposure to sunlight and other environmental forces.

The Santa Monica-based non-profit 5 Gyres Institute is studying the impact of micro-beads and other microplastics on aquatic environments and found that a single tube of facial cleanser can contain over 300,000 micro-beads.

And, in a study published last year in Marine Pollution Bulletin, 5 Gyres reported that the surface waters of the Great Lakes averaged 43,000 microplastic particles per square kilometer: Many were tiny spheres matching those in personal care products. Micro-bead density was as high as 600,000 per square kilometer in one sample. Lead author Marcus Erickson has also informally sampled the Los Angeles River and found an abundance of plastic micro-beads there too. These startling findings add to a growing body of evidence that microplastics are building up in all bays, gulfs and seas worldwide.

Plastic debris of any size represents a dual chemical threat to aquatic environments, both from noxious chemicals manufactured into them (like bisphenol-A and phthalates) and because plastics are lipophilic, meaning oily pollutants found in water environments are attracted and adhere to their surface. As early as 2001, for example, scientists discovered that virgin pellets of PP exposed to coastal Japanese seawaters adsorbed toxic chemicals, like polychlorinated biphenyls (PBCs) and a breakdown product of the banned pesticide DDT, up to a million times their concentration in the surrounding water. Other risky chemicals, including flame retardants, have since been added to the list of pollutants associated with marine plastics.

Consequently, plastic debris ingested by sea creatures has become a potential threat to the ocean food chain, and scientists have already documented the ingestion of plastics by many fish species as well as marine creatures as small as barnacles and as large as whales. Over half of sea turtles found dead have ingested plastic. Studies are also emerging documenting the bioaccumulation of chemical pollutants in fish and other animal tissues when plastics are ingested. For microplastics, this threat is magnified by their small volume which means greater relative surface area to which pollutants can adhere.

Recent research suggests that micro-beads are among the very worst offenders expressly because they are made of PE or PP. A research team led by Chelsea Rochman at U.C. Davis deployed various types of mass-produced plastics into San Diego Bay for up to a year and found that, compared to other polymers, PE and PP soaked up higher concentrations of measured pollutants: PCBs and polycyclic aromatic hydrocarbons (PAHs). In a particularly disturbing follow-up study published in Scientific Reports last November, Rochman and colleagues observed liver toxicity in fish attributable to pollutants picked up from San Diego Bay when, for two months, the fish diet contained ground up PE previously deployed in the bay. Such findings notch up the concern that human health could also be impacted by plastics accumulating in the ocean food web.

According to Plastics Europe, an industry association, global plastics production reached 288 million metric tons in 2012 and is projected to continue its rise. Oceans cover 71 percent of the earth’s surface (roughly 140 million square miles) with an average depth of over 2.6 miles. The United Nations Environment Program estimates that there are already 46,000 pieces of plastic per square mile of ocean, distributed on the surface and seafloor and throughout the water column. The plastic burden of the Pacific Ocean alone is thought to total 18 million tons.

Given the ocean’s vastness, there’s no practical or impractical means to remove the existing plastic pollution. The idea of somehow filtering out all the microplastic debris is doubly absurd.

The only rational solution is to stem the inflow of further plastic pollution. For micro-beads, the means of accomplishing this is straightforward. Industry must eliminate plastic micro-beads from all products and replace them with biodegradable alternatives, like apricot pits, cocoa beans, walnut shells, dried coconut or salt.

5 Gyres is spearheading a global Beat the Micro-Bead campaign to both urge consumers to read product labels and pressure retailers and manufacturers to eliminate plastic micro-beads. So far, the list of corporations that have promised to reformulate their products without plastic micro-beads includes Johnson and Johnson, Unilever, The Body Shop, L’Oreal, Colgate-Palmolive, Beiersdorf, and Proctor & Gamble. None has yet delivered.

A handful of states might not wait for industry to act. Bills banning micro-beads have been introduced in Illinois, Minnesota, New York and Ohio. In California, similar legislation prohibiting the sale of “microplastics” in personal care products by 2019 passed the State Assembly on May 23 (AB1699).

Plastic micro-beads are used for maybe a minute before they’re mindlessly washed down the drain, exemplifying a consumer society paying little attention to the makeup or fate of its waste. The fact that micro-beads might come back to haunt us via our dinner plates is food for thought.