Environmental studies on pollution by industrial wastewater and using chitosan based nanocomposites for its treatment in some Egyptian Governorates

Abstract

The environmental pollution with industrial wastewater pollutants, especially heavy metals, is one of the most prominent problems in the world, especially Egypt. These metals have the ability to change the functions of important biological molecules such as protein, enzymes and amino acid, which leads to serious diseases in animal and human himself. The field study was conducted in three Egyptian governorates (El-Sharkia, El-Menofia and El-Fayium) by collecting samples of fish, soil, vegetables, and industrial wastewater from three sites of each governorate to study the concentration of lead, copper, cadmium, iron and zinc. In the present study the concentrations of 5 heavy metals (Pb, Cu, Cd, Fe and Zn) in the collected wastewater samples were studied and indicated that the highest mean concentration of Fe and Zn (6.24 mg/L and 3.21 mg/L respectively), were observed in F1site: Koum Oshim industrial region in El-Fayium governorate, while, the greatest mean concentration of Cu (9.99 mg/L) was detected in S1 site (Abbasa drain) in El-Sharkia governorate. Moreover, the highest mean concentration of Pb and Cd (12.7 and 1.61 mg/L, respectively) was showed in M1 (Quesna industrial zone) and M2 (El- Khadrawia drain) sites respectively, in El-Menofia governorate. According to FAO and WHO, the MPL for Pb , Cd, Cu, Fe and Zn are 5 , 0.01, 2, 5, 2 mg/l respectively. The current results of the wastewater physciochemical paramerters indicated that the TDS (total dissolved solids) values ranged between 381-1485 mg/L and the highest value was observed in M1 site in El-Menofia governorate and the highest value of the EC (electrical conductivity) was detected in the same region (2122 μs/cm). Meanwhile the pH values was in the alkaline range in the three governorates (7.1-8.4) and the greatest value (8.4) was showed in M1 site. The DO (disolved oxygyn) values were ranged between 0.2-1.4 mg/L . The acceptable limits of EC and TDS are 1000 μs/cm and 500 mg/l respectively. In the current study, the collected fish samples were used as bio-indicator of heavy metals pollution in aquatic ecosystems. The concentration of lead, copper, cadmium, iron and zinc in the collected Nile tilapia samples was investigated. The highest mean concentration of Fe and Cu (314 and 11.2 mg/L, respectively) was detected in F1 site (Koum Oshim industrial region) in El Fayium governorate, while the greatest mean concentration of Pb (1.984 mg/L) was observed in M1 site (Quesna industrial zone) in El-Menofia governorate. The mean concentration of Cd and Zn was within MPL (30 mg/kg for Zn and 0.2 mg/kg for Cd) in the three governorates. The Maximum Permissible Limits for Pb, Cu and Fe are 0.5, 10, 146 mg/kg respectively.