NOAKHALI: The presence of microplastics in floating micro-organisms or zooplankton is an ominous signal to the human body. Zooplanktons consume various types of microplastics as food particles, which later enter the human body through the food chain and have harmful effects.
A group of researchers headed by Najmus Sakib Khan, chair of the Department of Oceanography, Noakhali Science and Technology University (NSTU). Bangladesh first detected the presence of these microplastics in the copepod genus of zooplankton in 2021. This research was conducted at the Coastal Plankton Laboratory at NSTU.
Plankton is the main driving force of the aquatic food cycle. The presence of zooplankton is essential in all aquatic ecosystems such as rivers, canals, estuaries, seasonal wetlands, or oceans and their roles in the food cycle are many. These tiny organisms are mainly two types — phytoplankton and zooplankton. The diet of all aquatic vertebrates and invertebrates depends on the species and quality of the zooplankton. Zooplankton also plays an indirect role in human nutrition.
Microplastic pollution is the riskiest of all types of pollution. It gradually enters the human body like a silent killer through daily eating habits. In the near future, it may become essential to detect the presence of microplastics in blood in human diagnostic tests. The final destination of the plastic products used by humans is Canals, Rivers, Estuaries, and lastly in the Ocean. It takes hundreds of years for some plastics to biodegrade. These tiny plastic particles are divided into several categories based on their size such as microplastics (<5 mm) and nanoplastics (1-1000 nano mm). These smaller plastic particles are mistakenly consumed by zooplankton as food. The presence of microplastics in the stomach or body of marine mammals, birds, and other fishes has already been proven. Scientists are conducting research both in Bangladesh and abroad in this regard.
Aquatic mammals and fish are less likely to directly ingest plastic particles. They can vomit the wrong food, but not always. But if these animals at the top of the aquatic food chain are ingesting microplastics through zooplankton, it is quite worrying. The attractive color, shape and novelty of small plastic particles easily influence zooplankton to accept them as food. Copepods find their own food and take it according to taste, and if they accidentally ingest plastic particles, they cannot regurgitate them.
Due to the increasing level of plastic pollution in our rivers and estuaries, the amount of microplastic particles taken by zooplankton is also increasing alarmingly. Based on this apprehension, the first microplastic detection research in zooplankton was initiated in Bangladesh under the ongoing funding of Special Research Allocation (2020-21) and (2021-22) of the Ministry of Science and Technology of the Government of the People’s Republic of Bangladesh and this sophisticated research is also monitored by National Oceanographic and Maritime Institute (NOAMI). The Coastal Plankton Laboratory first identified plastic particles in the bodies of copepods at the Department of Oceanography, NSTU. This year, samples of the copepod were sent to the Bangladesh Oceanography Research Institute (BORI) for more intensive research. Researchers from this reputed institute also confirmed the presence of microplastics in copepod zooplankton.
The detection of microplastics in zooplankton is also an ominous signal for marine biodiversity. As these plastic particles enter the body of fish through zooplankton, they are entering our bodies through fish food. If this plastic pollution is not controlled soon, this microplastic will become a silent killer like arsenic and cause various diseases in our bodies.