Microplastics

Microplastics are small pieces of plastic debris, less than 5mm in size, that are either intentionally manufactured at that size or result from the degradation of larger plastic items. They are a significant environmental concern due to their persistence in the environment, potential for ingestion by wildlife, and potential to carry toxic chemicals.

Sources and types of microplastics

Microplastics can originate from a variety of sources. They can be intentionally manufactured for use in personal care products, such as exfoliating scrubs and toothpastes, where they are known as microbeads. They can also result from the breakdown of larger plastic items, such as plastic bags and bottles, due to physical processes (e.g., wave action) and photodegradation. This type of microplastic is often referred to as secondary microplastics.

Microplastics can be categorized into three main types based on their shape: fragments, fibres, and spheres. Fragments are irregularly shaped pieces that result from the breakdown of larger plastic items. Fibres are thin and elongated, often originating from synthetic textiles. Spheres are round and smooth, typically resulting from the manufacturing process of microbeads.

Environmental impact

Microplastics pose a significant threat to the environment due to their small size, which allows them to be ingested by a wide range of organisms, from small zooplankton to large marine mammals. Once ingested, they can cause physical harm, such as blockages in the digestive tract, and can also act as vectors for toxic chemicals.

Microplastics can absorb pollutants from the surrounding environment, including persistent organic pollutants (POPs) and heavy metals. These can then be transferred to organisms upon ingestion, potentially causing harmful effects.

Human health implications

The potential impacts of microplastics on human health are currently not well understood. However, there is concern that microplastics could enter the human food chain through the consumption of contaminated seafood. Further research is needed to fully understand the potential risks.

Mitigation strategies

Efforts to mitigate the impacts of microplastics include reducing plastic use, improving waste management practices, and developing biodegradable alternatives to conventional plastics. Legislation has also been introduced in some countries to ban the use of microbeads in personal care products.