Global Journal of Science Frontier Research, H: Environment & Earth Science, Volume 23 Issue 2

burning, emissions from operational industries, greenhouse gases, and landfills and wildfires. PAHs are organic contaminants mostly found in polymeric products and pollute the ecosystem(48-50). a) Effluent from the slaughterhouse Activities like roasting and washing from the slaughterhouse (abattoir) are good sources of contaminants. Disposal of this waste from the abattoir is a worrisome environmental challenge all over the globe. Using waste rubber in roasting slaughtered animals increased pollution in terrestrial, aquatic, and groundwater (51-52). The chemical properties of abattoir wastes are the same as that of municipal sewages, though the former is highly concentrated wastewater with soluble and suspended organic formations. Waste blood from the abattoir contains high chemical oxygen demand (COD) of about 375 000 mg/L, and it is one of the highly dissolved adulterants in abattoir wastewater (53-55). In Nigeria, there is no master plan for the disposal of effluents generated from abattoirs. The solid waste from the abattoir is collected and dumped in the landfills or open fields while the liquid waste finds its way into the water bodies or municipal sewerage system. These activities jeopardize human health coupled with terrestrial and aquatic life (56-57). Effluent from an abattoir can lead to an increase in biochemical oxygen demand (BOD), COD, pH, temperature, and turbidity, which may even lead to a lack of oxygen in the water bodies (58-59). b) Effluent from the Cassava Industry Cassava is known by its genus Manihot esculanta crantzcrantz and is mainly consumed in Africa, Asia, India, and South America (60-61). One of the processing methods include direct fermentation to get fufu (62-63), grating and fermentation to obtain garri flakes (64-65),grating and fermentation to obtain garri flakes (66-67), to obtain tapiocca (68). The liquid from cassava processing units contains a dangerous liquid called cyanide which is acidic in nature (69-70). Because of improper disposal of these effluents, the site is left to develop a foul odour while the effluents find their way to the water bodies and some percolates into the groundwater leading to another risk as elucidatedin (Fig. 2). The odour generated from the industry site cannot allow residents living near the factory to breath freely. The effluent from the cassava waste kills all the grasses along its parts due to the acidic content of the wastewater creating artificial soil erosion. Cassava effluent breeds various types of bacteria and fungi in the soil and affects public health when washed into the water(71-72). Some domestic animals and birds feed directly from this cassava effluent and when consumed leads to dangerous health problems. All these could pose an environmental problem shortly due to the lack of effluent treatment facilities. Figure 2: Effect of Cassava Effluent on the Environment c) Effluent from Fruit Juice Factory Fruit is one of the essential nutrients required by man for the maintenance of the body. It is consumed by everybody in one form or the other. Some eat it as raw fruit, while others prefer consuming it as juice after processing. Fruits are the major sources of vitamin C(73-74). A deficiency of vitamin C in our diet can cause scurvy in children and other health implications in adults(75). Effluent from fruit juice factoriesis a source of emerging contaminants that could pollute freshwater easily(76). It is also a breeding ground for mosquitoes, flies, and other dangerous insects. The odour from the 1 Year 2023 3 © 2023 Global Journals Global Journal of Science Frontier Research Volume XXIII Issue ersion I VII ( H ) An Overview on Engineering Bio-Treatment Methods for Effluent in Food Processing Industries