WRITTEN BY MARITA SCHMID
ON LEG TWO FROM AZORES TO ANTIGUA WITH COPERNICUS MARINE SERVICE
Attenuated total reflectance Fourier transformation infrared spectroscopy… aka the Magic machine that tells what kind of plastic we found.
What it does in simple terms is shoot infrared light through a material to measure the reflection waves which identifies the type of material. We have seen a very similar technology using infrared light when we visited the sorting facility in Ponta Delgada. There we saw how the rigid containers and PET bottles were separated from the rest of the material. eXXpedition sponsor TOMRA is one of the main producers of these kinds of waste sorting machines.
The analysis takes some skills, as the plastics we are retrieving from the environment have all sorts of biofouling, such as algae on their surface, we must use a scalpel to clean the surface to remove any surface contamination, next putting on pressure (to fix the material over the scanning surface) and finally patience to wait for background scan and sample analysis to be done by the computer program.
So far, we have analysed about 30 samples which took about 2 hours. The vast majority of the plastic came out as HDPE (High density Polyethylene). This is not surprising, as it is a very commonly used material in packaging and building and construction. According to Geyer et al., 2017 “Production, use, and the fate of all plastics ever made”, 16.3% of the total polymer resin material production from 2002 – 2014 was HDPE. Common uses are in rigid bottles or containers for food, drink or personal care products. In 2015 52 MT primary production of HDPE correspond with 40 MT primary HDPE waste generation.
Other materials identified by the magic machine were PA (Polyamide, otherwise known as Nylon) and PP (Polypropylene).
The magic will go on throughout our voyage to gather information contributing to a scientific database about plastic floating in the ocean.
The FTIR machine on board S.V. TravelEdge has been provided by our scientific partner PerkinElmer.