The Damaging Effects of Microplastics

What are Microplastics?

Microplastics are plastic particles smaller than 5 mm. Microplastics or “MP’s” as we will now refer to them, are categorized into primary and secondary. Primary MP’s include the small plastic pieces or “pellets” used for the production of almost all plastic products. Secondary MP’s are the pieces of the manufactured products that have broken down into smaller pieces.

Because plastic is synthetic, it does not break down into soil like organic things do. Instead, the plastic is broken down into smaller and smaller pieces by the elements. UV rays from the sun break down these materials, along with wind and movement of water, and they eventually reach the size of MP’s.  

How do Microplastics get into our bodies?

As plastic materials break down they are washed away and blown into the sewer systems of our towns and cities. Some of the particles from there go into sewage treatment, but because of their size, many particles get through filtration systems and end up in the tap water. The particles that do not go through sewage treatment (most MP’s) end up in the ocean. Creatures mistake these particles for food. Also, Zooplankton consume them and they are then sent up the food chain, ending with human consumption. 

What effects do Microplastics have on our health?

Unfortunately, there has not been enough research conducted to see clear effects of MP’s in humans. There have been more studies done on some of the chemicals used in the production of plastic and its health effects, than on MP’s. A reason for this may be that plastic products are technically non-toxic, although chemicals used in their production are quite toxic, because they are not able to be absorbed by biological membranes. But when the products are broken down into MP’s, they are absorbed into biological membranes. We know this from studies that have been done on animals. 

Lab research has shown that blue crabs that had been exposed to MP’s had reduced respiratory function. Also, blue mussels exposed to MP’s showed formations of granulomas (mass of immune cells.) 

One study conducted on animals was the effects of MP’s on immune cells. These cells are responsible for fighting off bacteria and other harmful microorganisms. This study showed that when some of the cells tried to do their job of eliminating the foreign object (MP’s), they consumed the plastic, which resulted in cell death.

Can we assume then that these micro plastics are not good for human health? Animal studies only give a glimpse of what MP’s could do in a human body. There isn’t enough data to say they are negative for human health, but we do know that chemical products that are used in the manufacturing of plastic, such as BPA, is indeed harmful to health.