Plastics have woven their way into the fabric of our daily lives, offering unparalleled convenience and shaping modernity with their versatility. Yet, their enduring presence comes at a steep environmental cost, as the relentless accumulation of plastic waste casts a long shadow over ecosystems worldwide. This shadow extends to microplastics, tiny particles that pose unseen threats to biodiversity and human health alike. With the spotlight increasingly on microplastic pollution, Africa’s vital freshwater systems, such as the iconic River Nile, have remained underexamined until now. Through the lens of the Nile Tilapia, a key species to both local ecology and economy, a new study brings to light the pervasive challenge microplastics present in the heart of Africa, marking a critical step toward addressing a global environmental dilemma.
In a groundbreaking study published in Heliyon, scientist Dr. Dalia Saad and her student, Hadeel Alamin from the University of the Witwatersrand have identified the first evidence of microplastic pollution in the River Nile at Khartoum, Sudan, using Nile Tilapia fish as bio-indicators. This research highlights a concerning level of microplastic particles in one of Africa’s most significant waterways.
Ms. Alamin highlighted, “Thirty Nile Tilapia fish were used to bio-monitor the presence of MPs in the River Nile in Khartoum. Microplastics were found in all examined Nile Tilapia specimens. The dominance of tiny MPs and fibers, as well as the signs of fragmentation, indicate that they are predominantly smaller fragments of larger plastics. Activities such as agriculture, recreation, and industry are all potential sources of MP contamination”.
The methodology employed by Ms Alamin and Dr. Saad was meticulously designed to ensure accurate detection and analysis of microplastics in the Nile Tilapia. Initially, the fish were obtained fresh from a local market and subsequently transported to the laboratory where they were kept frozen until dissection. The digestive tracts of the fish were then carefully dissected out and subjected to a process to extract microplastic particles.
Once the microplastics were extracted, they underwent a thorough physical examination under a microscope, allowing the researchers to observe, measure, and photograph all suspected particles. The physical characteristics such as size, shape, and color were meticulously documented. To ascertain the chemical composition of the microplastics, a specialized technique was employed, enabling the identification of polymer types present within the samples.
Dr. Saad elaborated on the findings, stating, “In this investigation, microplastics were found in all Nile Tilapia specimens. The high prevalence of microplastics in the fish may reflect the extent of plastic pollution in the River Nile, showing that the aquatic life in the Nile is at risk of ingesting microplastics and associated contaminants”. Furthermore, she added, “The predominance of tiny microplastics is frequently reported in different aquatic fauna in several aquatic environments around the world. This may indicate a higher abundance of tiny microplastics in the river due to frequent fragmentation by several environmental processes”.
The study also pointed out the sources of microplastic pollution, as Dr. Saad explained, “Khartoum is confronted with poor waste management due to funds shortages, inadequate facilities for waste collection/disposal, and a lack of urban planning and environmental legislation. Thus, large quantities of solid waste, including plastics, end up in landfills and/or illegal dumping”. To add to this, the city’s wastewater treatment system is ineffective. The three wastewater treatment plants in Khartoum state, Karary, Wd-Daffiaa, and Soba, are outdated and do not meet local and international standards. That means untreated effluent from domestic, industrial, and agricultural activities is another probable source of microplastic pollution.
There are also countless recreational sites along the River Nile in Khartoum. The Nile Street is the most popular in the capital city, hosting water sports, restaurants, cafes, clubs, event venues, and hotels, as well as the tea ladies (women who serve hot beverages from makeshift mobile cafes along the banks of the river). However, waste disposal and collection practices are sorely lacking, so plastic litter from these leisure activities leaks into the river. This research is not only a call to action for Sudan but also for the global community to address plastic pollution more aggressively. With the Nile River being a vital resource for millions, the findings underscore the urgency of developing effective waste management strategies and policies to mitigate this environmental threat.
JOURNAL REFERENCE
Dalia Saad, Hadeel Alamin, “The first evidence of microplastic presence in the River Nile in Khartoum, Sudan: Using Nile Tilapia fish as a bio-indicator,” Heliyon, 2024.
DOI: https://doi.org/10.1016/j.heliyon.2023.e23393.
ABOUT THE AUTHORS
Dalia Saad is a trained Environmental Chemist, an educator and a researcher.
Dalia holds a BSc (Honours) in Chemistry from the University of Khartoum in Sudan(2006), an MSC (2011), and a PhD (2013) in Environmental Chemistry from the University of Witwatersrand.
She is currently a Researcher and a Royal Society FLAIR Fellow at the School of Chemistry at Wits; and a part-time Lecturer at the Department of Chemistry, University of Pretoria. Before joining Wits in 2021, she worked at various institutions on a full-time and research-visits basis (Khartoum University in Sudan, the University of Johannesburg and UNISA in South Africa, and the International Water Management Institute in Sri Lanka).
Dalia`s research interest is promoting access to clean water, namely, materials development for wastewater treatment (Polymeric materials, bio-adsorbents, and nanomaterials), emerging pollutants, and resource recovery and reuse. She is also interested in the social aspects of water management and the safe reuse of recycled water. With generous funding from the Royal Society, UK, she leads a research group investigating microplastic pollution in African freshwaters. Her research has gained national and international recognition and media attention.
Dalia has completed several international pieces of training, received various international awards, and numerous research and mobility grants from several organisations including, The Royal Society – UK, Royal Society of Chemistry, Robert Bosch Stiftung, the African Academy of Sciences, and the Organisation for Women in Science in the Developing counties (OWSD), among others. Dalia is a FLAIR-Royal Society Fellow, Africa Science Leadership Program Fellow, TWAS Young Affiliate, and an alumna of the OWSD fellowship program. She is a member of several professional bodies, and an ex-member of the executive committee of OWSD – South Africa National Chapter, and the founder of OWSD – Sudan National Chapter.
Hadeel Alamin is a MSC student at Wits University. She obtained her basic degree in Chemistry from the University of Khartoum (2015), where she works as a teaching assistant.
