Microplastics are small plastic particles less than 5 mm (~0.2 in) in size. There are three main sources of microplastics:
Primary microplastics are manufactured for use in a variety of household and industrial applications. The most common are those used as exfoliants in facial cleansers and abrasives in toothpaste. Do we need them? No! There are many alternatives.
Steps are being taken to stop their use. The US government has just recently signed a bill to ban the bead from use in these products. However, a global ban is necessary to prevent more pollution from these unnecessary pollutants.
Secondary microplastics small plastic particles that have been formed from the breakdown of larger plastic waste.
The UV radiation from sunlight is the main cause of this degradation. It reacts with the plastic and makes it brittle over time. The plastic can then be broken up by waves and abrasion with coastal sand and rocks.
Preventing plastic waste and debris from getting into the ocean is the only way to prevent the formation of these microplastics.
Other sources of microplastic pollution include: fishing line discarded or lost from fishing vessels; and fibres that are washed off synthetic clothing. As many as 2000 fibres are washed down the sink after a single wash!
So where does it all go?
The combination of these sources has resulted in the accumulation of microplastics in our oceans and on our coastlines worldwide. It been predicted that as much as 10% of all plastic manufactured each year is ending up in the oceans! The numbers are mind-boggling.
Plastics that do not sink can travel by ocean currents to either: the worlds great ocean gyres; or be washed onto your local beach. Go take a look at the strand line where stuff washes up on your beach. You’ll find plastic.
Microplastics are eaten by marine animals.
Microplastics will not break down for a very long time (years to decades). This is a problem as these little particles can look like food for the small animals at the base of our food chain. We now know that species as small as plankton and as large as fish will ingest microplastics. This may cause damage by: reducing their intake of normal food; damaging their gut; and shifting (translocating) into other cellular tissue where it may cause harm.
What’s worse is that microplastics can act like little sponges while out in the ocean. The surface of the plastic can have concentrations of harmful pollutants (such as DDT and other persistent pollutants) up to one million times that found in the water. This can be transferred to ocean creatures once eaten. Which may be transported higher up the food chain. Which may ultimately be transferred to us.