Water quality and physicochemical parameters of outgoing waters in a pharmaceutical plant

Abstract This work has focused on a pharmaceutical plant waters and the environmental impact of its discharges. The Water Quality Index (WQI), the Organic Pollution Index (OPI) and the Sodium Adsorption Ratio (SAR) of incoming and outgoing waters were analyzed over seasonal variations for 5 months using classical and mathematical indices. Highly significant increases were observed at the output (p < 0.001) for electrical conductivity, alkalinity, calcium and sodium; very significant (p < 0.01) for nitrites, COD and BOD5; significant (p < 0.05) for turbidity, potassium and chlorides. The sulfates, nitrates, phosphates, ammonia, TSS, magnesium, aluminum, iron and manganese showed no significant differences (p > 0.05). These parameters remained high all over the study period except for the BOD5. The WQI was reported in input waters in the range 85.9–89.5 indicating water safe for domestic use, range 42.3–60.9 (medium to bad) in output waters highlighting the water pollution. The OPI highlighted waters with low-to-moderate pollution, essentially due to high levels of nitrites. The SAR was found in “medium-to-high” salinity and “low sodium” ranges, thus precautions required in soils but without significant global effects. The COD/BOD5ratio highlighted a wastewater sometimes difficultly biodegradable (ratio > 3). In conclusion, often throughout all the study period, the outgoing waters were found with bad quality and non-negligible risks for soils; it is thus strongly advocated that these waters must undergo appropriate treatment to improve its physicochemical quality.