How plastics are entering the food chain

Vast amounts of plastic waste are thrown into the oceans every year, what would it mean if this plastic could, and was entering the food chain?

Professor Tamara Galloway in the College of Life and Environmental Sciences, whose research focuses on marine pollution, has been exploring this question through her Natural Environment Research Council (NERC) funded research.

Visiting almost any beach in the world you are likely to encounter plastic waste, this can range from larger items like milk bottle tops and films from plastic bags, but also much smaller plastics like the microbeads found in exfoliating face washes and toothpastes. These are small enough to wash down your sink and pass water filtration systems, and end up polluting the oceans.

By incubating zooplankton with these tiny plastic microbeads and studying them under a fluorescent microscope, Professor Galloway and her team have been able to show that zooplankton consume the microbeads and these are visible in their digestive tract.

They have also been able to track the amount of time the microbeads remain in the animal’s body before being expelled and study how this affects their growth, reproduction and survival. This is important because it helps us to understand how the microbeads and the chemicals might pass into the food chain when zooplankton are consumed by other larger creatures.

Professor Galloway said ‘By providing sound scientific evidence of the potential for marine litter to cause harm, we can support the policymakers who are working to protect the environment and human health. A first step towards solving this problem would be to reduce the amount of plastic litter and waste that we discard into the oceans’.