Investigating microplastics

I have always wanted to get involved with sustainability and climate change. This is why I choose civil engineering. Now, I get to research the behavior of microplastics as part of my individual research project. The Dynamics of Microplastics within cohesive sediments.

A microplastic is a plastic that is smaller than 5mm in diameter. They can be manufactured that size and lost during transportation or form due to erosion. Roughly, 8300 million metric tons of plastic have been manufactured to date. The life spans of microplastics are not known but it is estimated to be around 450 years. About 10 percent of plastic produced yearly end up in oceans, microplastics have been found across the world in remote places due to the ease at which they can be transported.

The biological impact of micro-plastics has been studied in shellfish. Microplastics have been found to impact reproductive systems, even affecting offspring. They can also lead to offspring ‘growing up’ smaller. We as humans can also be exposed to microplastics they accumulate up the food chain. It is estimated that a shellfish consumer is exposed to 11,000 microplastics every year. In Korea, a study found that in 100 grams of clam there were 34 micro-plastics. Which has definitely put me off mussels!

My project is simply put investigating the behavior of microplastics within clays; looking at whether they get trapped in sediments.

My research is aimed at hoping to understand how microplastics settle with turbulent environments, which could allow us to understand the current accumulation of microplastic.

To do this, I have my own lab space within the fluid’s lab in the Fulton building (The school of science and engineering). Using a settling column under the supervision of Alan Cuthbertson. Within this 2.1-meter-high column, I will create a realistically turbulent environment with clay suspended within a saltwater environment. Within which I will add a uniform, pre-calculated mass, of microplastic.

Using a high-resolution camera, I hope to obtain images of clay flocs that have microplastic embedded within it. Flocs are groups of sediment particles that have clumped together due to the turbulent environment.

So far, I have run a few experiments and characterized the microplastic’s settling velocity. Over the next four weeks, I will run a series of experiments. Below are a few images of clay flocs already collected.