Microbeads

Microbeads are manufactured solid plastic particles of less than five millimeters in their largest dimension. They are most frequently made of polyethylene but can be of other petrochemical plastics such as polypropylene and polystyrene. They are used in exfoliating personal care products, toothpastes and in biomedical and health-science research.

Microbeads can cause plastic particle water pollution and pose an environmental hazard for aquatic animals in freshwater and ocean water. In the US, the Microbead-Free Waters Act of 2015 phases out microbeads in rinse off cosmetics by July 2017.

Microbeads are manufactured solid plastic particles of less than five millimeters in their largest dimension, and commercially available in particle sizes from 10 micrometres (0.00039 in) to 1 millimetre (0.039 in). Low melting temperature and fast phase transitions make them especially suitable for creating porous structures in ceramics and other materials. They are most frequently made of polyethylene or other petrochemical plastics such as polypropylene and polystyrene.

Microbeads are added as an exfoliating agent to cosmetics and personal care products, such as soap, facial scrub and toothpastes. They may be added to over-the-counter drugs. In biomedical and health science research microbeads are used in microscopy techniques, fluid visualization, fluid flow analysis, and process troubleshooting.

Sphericity and particle size uniformity create a ball-bearing effect in creams and lotions, resulting in a silky texture and spreadability. Smoothness and roundness can provide lubrication. Colored microspheres add visual appeal to cosmetic products.

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