What are Microplastics?

Microplastics are small pieces of plastic material that we find in the marine environment and on our beaches and shorelines.  Some of them are so small that they cannot be seen with the naked eye.  Others can often blend in with the sand and organic material found on beaches making them hard to spot. They are classified into two groups:

  • Primary Microplastics – these are materials that were manufactured to be small, such as pre-production pellets (nurdles) and cosmetic micro beads.
  • Secondary Microplastics – these are materials that started life as larger products but have been broken down over time by wave action and sunlight.

There have been many attempts to standardise the definition of microplastics over recent years and recently it has become acceptable to classify microplastics as particles less than 5mm in size.

Timelapse video of microplastics being sorted from organic beach material

Why are Microplastics a Problem?

Plastic pollution is pervasive, pernicious and persistent and the problem is growing at a rate that is out of control. Large pieces of plastic pollution in the ocean cause harm to marine animals through entrapment and ingestion, whilst the sheer amount of plastic waste is increasing the transportation of invasive species around the world.

However, microplastics are far more insidious.  There are already billions of microplastic particles in the ocean and these are acting as transport vectors for a range of toxins and pollutants that are found in the oceans.  These toxins accumulate and magnify on the plastics.  When the plastics are ingested mistakenly these toxins enter the food chain, becoming more concentrated as they progress through it.  We are at the top of that food chain.  Around 17% of the worlds population rely on seafood as their main source of protein so the implications to human health are significant and worrying.

Microplastic ingested by plankton (Image source: Plymouth University)

Why do we need a Survey?

There is still much that we don’t know about the issues of microplastics.  For example, studies have found that some plastics will adsorb toxins more quickly than others and some colours may be more attractive to feeding birds and fish than others.  It is important to know what plastics we are dealing with, where they are and in what concentrations and this survey will provide an opportunity to gather large amounts of data that can be analysed, mapped and made available for further research and study.

microplastic pieces in the sieve