Assessment of Heavy Metals Pollution Status of the Pasture Grass around Katima Mulilo Municipal Solid Wastes Dumpsite, Namibia

Abstract

Abstract-Environmental effects of open wastes disposal continue to receive global attention. This study determined the heavy metals pollution status of pasture grass around Katima Mulilo municipal solid wastes dumpsite, Namibia. Samples of the pasture grass were collected from grassland around the wastes dumpsite and a control site and then analyzed for levels of the heavy metals: Pb, Cr, Cd, As, Ni, Co, Cu and Mn using standard analytical procedures. The results obtained revealed that Mn recorded the highest mean concentration of 102.50mg/kg while Co recorded the lowest level (0.13mg/kg). Generally, the present levels of the heavy metals were below their health regulatory limits. However, the degree of contamination of the pasture grass was significantly higher (paired sample mean t-test, p < 0.05) in the samples collected around the wastes dumpsite with an index of 0.3502. The loading values obtained from the principal component analysis of the heavy metals suggest that all the seven metals detected can be grouped under one main factor. Therefore, we recommend periodic monitoring of the levels of heavy metals in the pasture grass around the wastes dumpsite and advice precautionary measures in order to limit unintended exposures of livestock and hence, human beings to metals toxicities.

Food Safety Analysis of Milk and Beef in Southwestern Uganda

“…In Uganda, food safety assessment on milk and beef has been on microbial load [ 27 , 28 ]; however, the current study shows that inorganic pollutants, which are more resistant to heat treatment, would pose a bigger public health problem to the general population. This is because long-term ingestion of livestock products, derived from livestock which graze on pastures polluted with heavy metals, would lead to development of major health hazards in man such as cancer, organ failure, and death [ 29 ].…”

“…Food safety studies on milk and beef in Uganda had previously placed a lot of emphasis on microbial load [ 27 , 28 ], leading to a scarcity of information on the inorganic pollutant load. This is important since human exposure to milk from cows that graze on heavy metal-polluted pastures has been associated with long-term health hazards such as cancer, organ damage, failure, and inflammation [ 29 ]. This makes research to determine the level of inorganic pollutants in animal products important, especially at the time when industrialization and chemical use have increased significantly.…”

Heavy metals pollution status of the Katima Mulilo Urban open land wastewater disposal centre and the immediate vicinity

“…The result of analysis of variance (ANOVA) between the mean heavy metals concentrations in the surface soil at the different sampling sites (Table 2) was statistically significant (P < 0.05). This result might be due to varying degrees of metal inputs from anthropogenically derived sources across the sampling points (Abah et al, 2017). However, as identified by Long et al (2002), irrespective of the origin of heavy metals in soils, excessive levels of many metals can result in soil quality degradation as well as posing significant hazards to plants, humans, animals, and ecosystem's health.…”

“…Generally, the concentrations of the heavy metals recorded across the sampling sites were lower than their corresponding WHO's recommended maximum permissible concentrations in soil (Table 1). However, as reported by Abah, Mashebe, and Onjefu (2017), the presence of heavy metals in soils, especially where humans and livestock traverse intensively constitutes health concern due to frequent exposure to the contaminant-bearing dusts emanating from the soil. Heavy metal contamination of soil may pose risks and hazards to humans and the ecosystem through: direct ingestion or contact with contaminated soil, the food chain (soil-plant-human or soil-plant-animal-human), drinking of contaminated ground water, reduction in food quality (safety and marketability), reduction in land usability for agricultural production causing food insecurity, and land tenure problems (Ling, Shen, Gao, Gu, & Yang, 2007;McLaughlin, Hamon, McLaren, Speir, & Rogers, 2000).…”

“…Of particular concern, heavy metals toxicity in the human ecosystem has been identified as a clinically significant condition (Ferner, 2001), and if unrecognized or inappropriately treated, the toxicity can result in significant illness and reduced quality of life (Amirah, Afiza, Faizal, Nurliyana, & Laili, 2013). Thus, for the protection of human and ecosystem's health from unintended exposure to heavy metal pollution, it is important to evaluate and document the presence and sources of heavy metals in every environmental component that affects human health (Abah et al, 2017).…”