In our haste to ban or regulate unsustainable and environmentally damaging materials and chemicals, we may overlook dangers posed by their substitutes. In light of the scientific evidence regarding the fate, persistence and toxicity of microplastics in the marine environment, many countries have banned the sale of rinse-off cosmetics containing plastic microbeads to prevent their release to the environment. However, the wider lifetime environmental impacts of the potential substitutes have not up to now been considered, and care must be taken so that the environmental costs of using them do not potentially outweigh the benefit resulting from the bans. In this study, we use Life Cycle Assessment to compare the environmental performance of a wide range of potential alternatives. The study investigates the quantities of these materials required, and the human health and environmental impacts of their manufacture, transport and inclusion in cosmetics. We highlight that long-term environmental and human health effects of their disposal are unknown and are thus excluded from the Life Cycle Assessment. In support of the responsible replacement of plastic microbeads in cosmetics, we identify several alternatives that will perform better, as well as substitutes that could pose additional risks and have undesirable effects.