Impact of sewage contaminated water on soil, vegetables, and underground water of peri-urban Peshawar, Pakistan

• Published in: Environmental monitoring and assessment Vol. 184; no. 10; pp. 6411 - 6421
• Main Authors: Ullah, Hidayat, Khan, Ikhtiar, Ullah, Ihsan
• Format: Journal Article
• Language: English
• Published: Dordrecht Springer Netherlands 01.10.2012; Springer Nature B.V
• Subjects: Agriculture - statistics & numerical data; Atmospheric Protection/Air Quality Control/Air Pollution; Carbon; Cation exchange; Cities; Crop yield; Crops; Drinking water; Earth and Environmental Science; Ecology; Ecotoxicology; Environment; Environmental Management; Environmental Monitoring; Food chains; Food contamination & poisoning; Food Contamination - analysis; Food Contamination - statistics & numerical data; Food quality; Groundwater - chemistry; Heavy metals; Impact analysis; Irrigation; Irrigation practices; Irrigation water; Local population; Metal concentrations; Metals; Metals, Heavy - analysis; Monitoring/Environmental Analysis; Municipal water; Pakistan; Phytotoxicity; Sewage; Sewage - analysis; Soil - chemistry; Soil contaminants; Soil contamination; Soil pH; Soil Pollutants - analysis; Spectral analysis; Statistical analysis; Studies; Vegetables - chemistry; Waste Disposal, Fluid - statistics & numerical data; Water pollution; Peshawar Pakistan; Pakistan; Sewage water; Soil; Irrigation; Transfer factor; Vegetables; Heavy metals
• ISSN: 0167-6369; 1573-2959
• DOI: 10.1007/s10661-011-2429-4

The use of sewage-contaminated municipal water for irrigation of crops is an old practice in many big cities of Pakistan. Since the wastewater is rich in nutrients, it increases crops yield substantially but at the cost of food quality. The objective of this study was to investigate sewage water irrigation as a source of accumulation of heavy metals in soil and its subsequent transfer to crops and underground water. Sewage water, soil, groundwater, and crop samples were collected from selected areas around Peshawar city and analyzed for heavy metals concentration by atomic absorption spectroscopic method. Analysis of data revealed a considerable impact of the irrigation practices in the peri-urban Peshawar. Statistical analysis of the data showed a positive correlation between heavy metals concentration and soil carbon contents on the one hand and cation exchange capacity on the other. A strongly negative correlation was observed between metal contents and soil pH. The vertical movement of heavy metals from contaminated soil has polluted crops and underground water. The results indicated higher concentration of toxic metals in soil accumulated due to long-term sewage-contaminated water irrigation and their subsequent transfer to our food chain. The practice, if continued un-noticed may pose a threat of phytotoxicity to the local population.