Macrodebris and Microplastics Pollution in Nigeria: First Report on Abundance, Distribution and Composition

Abstract

The abundance, distribution and composition of marine debris (> 5 cm) and small microplastics (11 μm) from five rivers in South Eastern, Nigeria was investigated. This study provided the first assessment of the type and quantity of marine litter and microplastics in Nigeria. A total of 3487 macrodebris items/m2 were counted with the following distribution; plastics (59 %) > metal (10 %) > cloth (7 %), paper /cardboard (7 %), rubber (7 %) > glass/ceramics (5 %), medical and agro-based waste (3 %) > wood (2 %). The cleanliness of the river assessed with clean coast index (CCI) ranged from “very clean” at Okumpi and Obiaraedu river to “extremely dirty” at Nwangele river. Microplastics abundance ranged from 440 to 1556 particles/L, with high accumulation at downstream. Fragment shape was most abundant while fiber and film followed. The distribution of plastic types was; PET (29 %) > PE (22 %) > PVC (16 %) > PP (14 %) > other (6 %) respectively. Significant relationship was found between the total abundances of microplastics and different macrodebris groups suggesting that microplastics were abundant in areas where the macrodebris abundance was high. Our results provide baseline information for future assessments. Management actions should focus on input prevention including proper waste management, recycling of plastics, and strict penalties for illegal dumping of wastes.

The importance of microplastics pollution studies in water and soil of Nigeria ecosystems

“…Similarly, a study of Cross River, Qua Iboe River and Jaja Creek in Akwa Ibom, Nigeria for suspended marine litter also reported high quantity of plastic (> 5000 kg/ m 2 ) compared to other waste (can, foil etc < 1000 kg/m 2 ) [19]. Reports have shown that Macroplastics correlated strongly with microplastics indicating that wherever there is high abundance of macroplastics, there will be a corresponding high abundance of microplastics in that area [13,20]. Therefore, quantifying the abundance of microplastics and identifying their major sources in Nigerian environments is important to understand the potentially adverse impacts of microplastics to ecological systems in the country.…”

“…Taiwan), Australia, America (California, certain areas in Argentina, Brazil, Chile, and Colombia) while some African countries (Kenya, Mali, Cameroon, Tanzania, Uganda, Ethiopia, Malawi, Morocco, South Africa, Rwanda, and Botswana) have also banned plastic bags [11], though in principle but not in practice. In Nigeria, the problem of plastic pollution still persist and potentially on the increase, even though there are existing laws that may tackle these problems [12], but are not implemented or are poorly enforced [13]. Plastic industry in Nigeria is receiving massive investment and thus experiencing significant growth.…”

“…The steady and huge increase in production and consumption is responsible for high plastic waste generation in Nigeria (Figure 3). Recent studies have shown that plastic is abundance in inland freshwater systems in Nigeria, often received from cities via surface run off [13]. Enyoh et.…”

“…Enyoh et. al., in 2019 [13] reported that plastic contributed 59 % of the 3487 macrodebris items/m 2 counted from shore of Rivers in Nwangele Local Government Area of Imo state. Similarly, a study of Cross River, Qua Iboe River and Jaja Creek in Akwa Ibom, Nigeria for suspended marine litter also reported high quantity of plastic (> 5000 kg/ m 2 ) compared to other waste (can, foil etc < 1000 kg/m 2 ) [19].…”

“…Therefore, quantifying the abundance of microplastics and identifying their major sources in Nigerian environments is important to understand the potentially adverse impacts of microplastics to ecological systems in the country. Extensive studies are being conducted in other countries regarding the occurrence, fate, and implication of microplastic in ecosystems [3-4, 6, 8, 21-23], while similar studies in Nigerian environment are very scarce [13]. This is probably due to lack of awareness and/or lack of standard methods for analysis [24].…”