Study flags Bulimba Creek as Brisbane’s most contaminated waterway for hazardous microplastics

A new investigation by Queensland University of Technology has identified Bulimba Creek as the Brisbane waterway with the highest concentration of hazardous microplastics among three creeks examined, prompting concerns over ecological health and potential human exposure.

The research team collected water and sediment samples from Bulimba Creek and two additional Brisbane creeks, then used polymer analysis techniques to categorize the types of micro‑plastic particles present. Results, now published in the peer‑reviewed journal Marine Pollution Bulletin, show that Bulimba Creek carries a markedly larger load of particles considered hazardous due to their chemical composition and associated additives.

Microplastics—tiny fragments of plastic less than five millimetres in size—have become a ubiquitous pollutant in urban waterways worldwide. In city environments they often originate from storm‑water runoff, litter, tire wear, and the breakdown of larger plastic debris. Certain polymers and fibre types can leach additives such as flame retardants or heavy metals, making them especially risky for aquatic organisms that may ingest them, and potentially moving up the food chain.

Bulimba Creek traverses densely populated residential neighbourhoods and industrial zones before feeding into the Brisbane River. The creek’s elevated micro‑plastic burden suggests that local land‑use practices, inadequate storm‑water filtration, or point‑source discharges may be contributing to the problem. Given the creek’s role in regional drainage and recreation, the findings raise questions about water‑quality standards and the effectiveness of current pollution‑control measures.

Researchers recommend that authorities expand monitoring programs to track micro‑plastic levels over time and across a broader network of streams. They also propose practical mitigation steps, such as installing finer filtration in storm‑water drains, promoting community clean‑up initiatives, and reviewing zoning regulations that affect runoff. By targeting the most affected waterways, policymakers could reduce the overall load of hazardous particles entering the Brisbane River system.

The study adds to a growing body of evidence that micro‑plastic contamination is not uniform across urban catchments, underscoring the need for site‑specific assessments. Publishing the results in Marine Pollution Bulletin ensures the methodology and data are accessible to scientists and regulators worldwide, facilitating comparative studies and informing future strategies to curb plastic pollution at its source.