Microbeads are added as exfoliant to cosmetics and personal care products, such as soap, body scrub, toothpastes and creams. Their roundness and smoothness in creams and lotions create the silky texture, spreadability and lubrication. Coloured microspheres add visual appeal to cosmetic products. They are also added to some medicinal drugs and used in some research. Microbeads are washed down the drain, they may or may not be filtered through sewage treatment plants and make their way into rivers and oceans.
Microplastics, are today turning up in all the world’s major oceans including the Arctic and Antarctic and are likely the most numerically abundant items of marine plastic debris. Quantities will inevitably continue to increase as long as the use of microbeads is not forbidden and the release of plastics to the environment is not stopped (large, single plastic items ultimately degrade into millions of microplastic pieces). Particles make “plastic smog” that permeates our ocean water just like particulate matter permeates our air. Like smog in the air, ocean smog can’t easily be filtered out to fix the problem.
Plastic and beads absorb and concentrate organic pollutants like DDT, PCBs and PAHs, which start leaching out when ingested. In addition to the physical damage done by any plastic itself, the ingestion of micro-plastics introduces a potential for toxicity not only to these animals but also to their predators, increasing the transfer and biomagnification of harmful chemicals. Pathogenic bacteria also travel the waters on microplastics, thus increasing pathogenic risk far away from sources.
A variety of wildlife, from shells, small fish, amphibians and turtles to birds and larger mammals, mistake microbeads for their food source. Microparticles can be ingested by filter-feeding marine organisms such as oysters and mussels and induce a reaction within the tissue. Surface-skimming baleen whales filter enormous volumes of seawater for getting their food, the copepods and other small invertebrates – but with them, they also retain microplastics and microbeads (Rossi et al 2012). These microplastics may affect the filter-feeder system inside the whale’s mouth, besides introducing a higher concentration of contaminants and microbes than krill usually carries.
Public concerns about the potential impact of micro-plastics and microbeads on the environment and health have increased in the last decades. It has triggered a number of scientific investigations to determine their physical and chemical effects as well as international mitigating initiatives.