**3. Results**

The values of the physical and chemical parameters of effluent samples from the Brewery are presented in **Table 1** and **Figure 2** respectively. The pH values were 6.98, 6.20, 6.48, and 6.72 for sampling points A, C, D, and E respectively. In all sampling locations, the highest pH value of 6.98 was obtained at sampling point A and the lowest value of 6.20 was obtained at sampling point C.

The TDS values in the present work ranged from 4.0 to 48.0 mg/l. Dissolved oxygen values ranged from 4.70 to 23.60 mg/l for all sampling points. The highest (15.90) and lowest (0.40) biological oxygen demand values were recorded at sampling points C and A, respectively. The chemical oxygen demand in the present work ranged from 18.88 to 19.24.32 mg/l. The values of nitrate varied between 1.28–1.95 mg L-1. The highest (7.16) phosphate value was recorded at sampling point C and the lowest (6.93) at sampling point A. Sulfate values ranged from 31.69 to 35.39 mg/l for all sampling points. Chloride values ranged from 28.00 to 53.00 mg/l for all sampling points.

**Figure 3** shows the results of heavy metals concentration analyses of effluent samples across the study area. Among the 9 elements studied, concentrations of As, Pb, and Ni were higher than WHO recommended limits. In contrast, lower concentrations of Co, Mn, and Zn were observed in the different sampling locations. Elements displayed wide variations in their distribution, suggesting control of


*\*A-un treated effluent, B- treated effluent, C- contact point of the treated effluent with the river and D- 10 kilometers away from the contact point.*

### **Table 1.**

*Physical parameters of the studied effluents.*

*Pollution Evaluation of Industrial Effluents from Consolidated Breweries: A Case Study… DOI: http://dx.doi.org/10.5772/intechopen.105955*

### **Figure 2.**

*Chemical parameters from the studied effluents. DO: Dissolved oxygen; BOD: Biological oxygen demand; COD: Chemical oxygen demand.*

### **Figure 3.**

*Heavy metal concentrations.*

anthropogenic activities on water chemistry. Overall, concentration of the study elements followed the order: As >Fe > Mn > Zn > Ni > Pb > Cr > Co > Cd. The sampling site C recorded the highest concentration of Fe and As.
