Microplastics, which are very small pieces of plastic (<5mm), are formed during the degradation of larger plastic products and are found throughout the oceans. Most plastic pollution is washed into waterways and delivered to the coast by rivers, where it is trapped nearshore in estuaries and coastal ecosystems. While the sight of visible plastic debris on the beach is distressing, the presence and impact of microplastics go largely unnoticed due to their microscopic size. However, the consequences of microplastics in our waterways are far-reaching and profound. These tiny plastic particles can be ingested by microscopic aquatic organisms, leading to disruptions in food chains and starvation within ecosystems. Evidence suggests the environmental fate of microplastics can have negative impacts on invertebrates, including crustaceans and bivalves, reducing survival rate, feeding ability, and immune system function. Moreover, the consumption of microplastics by seafood species poses a direct threat to human health.
Additionally, microplastics can leach harmful chemicals into the environment and attract and concentrate heavy metals and organic pollutants, exacerbating the contamination of marine habitats. Unfortunately, we still know relatively little about the types of microplastics and the extent of their entry into Australia’s coastal oceans via rivers. There is currently limited information on the extent of microplastic pollution in the enclosed Moreton Bay and how it might be impacting the range of marine ecosystems within the Bay. We need to protect the health of our ecosystems, safeguard human well-being, and preserve the natural beauty of this precious marine environment. We, aim to provide a comprehensive assessment of types and concentrations of microplastics in Moreton Bay and we propose to analyse the Brisbane and Logan River waters flowing into the Bay, sediments in mangroves, seagrass, and reef areas (from across the Bay, including Pine and Caboolture Rivers and the Pumicestone Passage; islands including the Moreton, North Stradbroke, and Mud Islands) to understand the distribution and trapping efficiency of different ecosystems, and key marine species important to the local aquaculture industry – to evaluate the exposure and risk to the marine organisms within the bay.
Outcomes
Together with collaborators, A/Prof. Helen Bostock (UQ) and Dr. Alistair Grinham (UQ), we have analysed sediment samples from the Bay which shows the presence of seven different plastics. The total plastic concentration varied significantly across the bay, with the highest concentration of plastics found in the Northern Bay, Mangroves, and Seagrass areas and the least amounts of plastics found in the Southern Bay. Using the average concentrations of Microplastic in the samples from the north and the south of the bay and the bulk density of sediments in these regions, along with the volume of sediments in the top 10 cm of the bay, we estimate that the total microplastic budget for Moreton Bay is around 7,000 tonnes. To the best of our knowledge, this is the first study to determine the extent of microplastic pollution in Moreton Bay by providing an assessment of the spatial distribution of plastics, the types of plastic and the preliminary total budget of microplastics in the Bay. With the results from our preliminary study, it is imperative that we develop a comprehensive understanding of the types and distribution of microplastics in Moreton Bay to effectively address this pervasive issue.
We will collaborate, engage, and discuss the findings with First Nations organisation, Quandamooka Yoolooburrabee Aboriginal Corporation (QYAC) and Healthy Land and Water and local regional councils that manage the coastal regions around Moreton Bay. The data will provide a baseline to monitor the plastic and determine if there has been any impact of management controls in the future. The results will be presented at public talks, workshops and conferences and will be published in peer-reviewed journals as well as ‘The Conversation’.
Awards and Prizes
- Dr Elvis Okoffo was awarded the Max Day Environmental Science Fellowship Award by the Australian Academy of Science.
Media Releases
- UQ researchers recognised for their research on protecting the environment
- Thousands of tonnes of microplastics found in Moreton Bay
