Small pieces of plastics, usually smaller than 5mm. A growing volume of microplastics is found in the environment, including the sea, and in food and drinking water. Once in the environment, microplastics do not biodegrade and tend to accumulate, unless they are specifically designed to biodegrade in the open environment. Biodegradability is a complex phenomenon, especially in the marine environment. There are increasing concerns about the presence of microplastics in different environment compartments (such as water), their impact on the environment and potentially human health.