At less than 5mm in size, microbeads, the tiny plastic balls often found in face scrubs and shower gels, might look harmless, but they wreak havoc on the environment and have been the subject of controversy for a little while now.The US banned microbeads in personal care products earlier this year, and British MPs have issued fresh calls for them to be banned not only in the UK but worldwide.The government will consider banning them from being used in cosmetics if the EU doesn't pass a law against them, the BBC reported . But the Environmental Audit Committee said the beads should be banned completely to protect marine wildlife and the human food chain.“Cosmetic companies’ voluntary approach to phasing out plastic microbeads simply won’t wash. We need a full legal ban," said Mary Creagh MP, the committee chair. Unilever has taken steps to phase them out and L'Oreal has said it will do so by next year.So why are these little balls controversial? And is that extra level of exfoliation in your morning shower worth it? (A single shower can lead to 100,000 microbeads entering the ocean, said Creagh.)Microbeads are small enough to make their way into lakes and rivers through the water system and because of their size, they're easily ingested by wildlife and mistaken for food. They can then get stuck in marine creatures' stomachs.There could be up to 50 plastic particles in a plate of oysters, Professor Tamara Galloway from Exeter University told the BBC . “We don’t have any evidence yet for the harm this might cause but most people would probably prefer not to be eating microbeads with their food.”However, a global microbead ban won't solve the problem of microplastic pollution. Microbeads from cosmetics make up a tiny proportion – just 0.01% to 4.1% – of plastics in the ocean, reported the BBC Nevertheless, not buying products that contain these microplastics shows companies we care about the environment and could encourage them to stop including microbeads in their products.Read the label when buying beauty products. "Microbeads" probably won't be on the ingredients list, so look out for the names of the petrochemical plastics they're made from, such as polyethylene and polypropylene.