Study of Heavy Metal Accumulation in Sewage Irrigated Vegetables in Different Regions of Agra District, India

Preeti Parashar, Fazal Masih Prasad

School of Chemical Sciences, Department of Chemistry, St. John’s College, Agra, India..

DOI: 10.4236/ojss.2013.31001                

Abstract

Heavy metal contamination of soil resulting from sewage irrigation is a cause of serious concern due to the potential health impacts of consuming contaminated products. In this study an assessment made of the impact of sewage irrigation on heavy metal contamination of Spinach, Cabbage, Beetroot, Reddish, Okra, Tomato, and Cucumber is widely cultivated and consumed in urban India, particularly by the poor. A field study was conducted at seven major sites that were irrigated by either treated, (Dhandupura) or untreated wastewater in the suburban areas of Agra, India. Samples of irrigation water, soil, and the edible portion of all the vegetables were collected monthly during the winter seasons and were analyzed for Fe, Cd, Cu, Zn, and Pb. Heavy metals in irrigation water were below the internationally recom- mended (WHO) maximum permissible limits set for agricultural use for all heavy metals except Cd at all the sites. Similarly, the mean heavy metal concentrations in soil were below the Indian standards for all heavy metals, but the maximum value of Cd recorded during January was higher than the standard. However, in the edible portion of spinach, the Cd concentration was higher than the permissible limits of the Indian standard during summer, whereas Pb concentrations were higher in winter seasons. Results of correlation analysis were computed to assess the relationship between individual heavy metal concentration in the vegetable samples. The study concludes that the use of treated and untreated wastewater for irrigation has increased the contamination of Cd, Pb in edible portion of vegetables causing potential health risk in the long term from this practice. The study also points to the fact that adherence to standards for heavy metal contamination of soil and irrigation water does not ensure safe food. Fe was measured abundant in soil whereas Pb and Cd were found more in untreated sites as compared to treated site. Correlation, paired T-test and ANOVA were also carried out for pre post harvested soil and vegetables.

Keywords

Heavy Metals; AAS; Sewage; Pearson Correlation; Paired T-Test; ANOVA

Conflicts of Interest

The authors declare no conflicts of interest.

References

[1]	F. Mapanda, E. N. Mangwayana, J. Nyamangara and K. E. Giller, “The Effect of Long-Term Irrigation Using Waste- water on Heavy Metal Contents of Soils under Vegetables in Harare, Zimbabwe,” Agriculture, Ecosystems & Environment, Vol. 107, No. , 2005, pp. 151-165. doi:10.1016/j.agee.2004.11.005
[2]	W. Wenzel, and F. Jackwer, “Accumulation of Heavy Metals in Plants Grown on Mineralized Solids of the Austrian Alps,” Environmental Pollution, Vol. 104, No. 1, 1999, pp. 145-155. doi:10.1016/S0269-7491(98)00139-0
[3]	K. P. Singh, D. Mohon, S. Sinha and R. Dalwani, “Impact Assessment of Treated/Untreated Waste Water Toxicants Discharge by Sewage Treatment Plants on Health, Agricultural and Environmental Quality in Waste Water Disposal Area,” Chemosphere, Vol. 55, No. 2, 2004, pp. 227-255. doi:10.1016/j.chemosphere.2003.10.050
[4]	S. Arai, “Global View on Functional Foods: Asian Perspectives,” British Journal of Nutrition, Vol. 88, Suppl. 2, 2002, pp. S139-S143.
[5]	M. S. Al Jassir, A. Shaker and M. A. Khaliq, “Deposition of Heavy Metals on Green Leafy Vegetables Sold on Roadsides of Riyadh City, Saudi Arabea,” Bulletin of Environmental Contamination and Toxicology, Vol. 75, No. 5, 2005, pp. 1020-1027. doi:10.1007/s00128-005-0851-4
[6]	D. Demirezen and A. Ahmet, “Heavy Metal Levels in Vegetables in Turkey Are within Safe Limits for Cu, Zn, Ni and Exceeded for Cd and Pb,” Journal of Food Quality, Vol. 29, No. 3, 2006, pp. 252-265. doi:10.1111/j.1745-4557.2006.00072.x
[7]	M. A. Radwan and K. A. Salama, “Market Basket Survey for Some Heavy Metals in Egyptian Fruits and Vegetables,” Food and Chemical Toxicology, Vol. 44, No. 8, 2006, pp. 1273-1278. doi:10.1016/j.fct.2006.02.004
[8]	K. Fytianos, G. Katsianis, P. Triantafyllou and G. Zachariadis, “Accumulation of Heavy Metals in Vegetables Grown in an Industrial Area in Relation to Soil,” Bulletin of Environmental Contamination and Toxicology, Vol. 67, No. 3, 2001, pp. 423-430. doi:10.1007/s001280141
[9]	I. Cakmak, “Possible Roles of Zinc in Protecting Plant Cells from Damage by Reactive Oxygen Species,” New Phytologist, Vol. 146, No. 2, 2000, pp. 185-205. doi:10.1046/j.1469-8137.2000.00630.x
[10]	A. Siedlecka and Z. Krupa, “Interaction between Cadmium and Iron. Accumulation and Distributionof Metals and Changes in Growth Parameters of Phaseolus Vulgaris L. Seedlings,” Acta Societatis Botanicorum Poloniae, Vol. 65, No. 3-4, 1996, pp. 277-282.
[11]	B. J. Alloway, A. P. Jackson and H. Morgan, “The Accumulation of Cadmium by Vegetables Grown on Soils Contaminated from a Variety of Sources,” Science of the Total Environment, Vol. 91, 1990, pp. 223-236. doi:10.1016/0048-9697(90)90300-J
[12]	B. Nrgholi, “Investigation of the Firoza Bad Waste Water Quality-Quantity Variation for Agricultural Use,” Final Report, Iranian Agriculture Engineering Research Institute, Karaj, 2007.
[13]	G. Ellen, J. W. Loon and K. Tolsma, “Heavy Metals in Vegetables Grown in the Netherlands and in Domestic and Imported Fruits,” Z Lebensm Unters Forsch, Vol. 190, No. 1, 1990, pp. 34-39. doi:10.1007/BF01188261
[14]	M. Qadir, A. Ghafoor, S. I. Hssain, G. Murtaza and T. Mahmood, “Copper Concentration in City Effluents Irrigated Soils and Vegetables,” Pakistan Journal of Soil Science, 1999, pp. 91-102.
[15]	M. Mostachari, “Investigation of Qazvin Soils and Plants Pollution with Heavy Metals during Irrigation with Waste Water,” Proceeding of 75 Water and Soil Conference, Persian, 2002.
[16]	T. Adhikari, M. C. Manna, M. V. Singh and R. H. Wanjari, “Bioremediation Measure to Minimize Heavy Metals Accumulation in Soils and Crops Irrigated with City Effluent Food,” Agriculture & Environment, Vol. 2, No. 1, 2004, pp. 266-270.
[17]	P. C. Prabu, “Impact of Heavy Metal Contamination of Akaki River of Ethiopia on Soil and Metal Toxicity on Cultivated Vegetable Crops,” Electronic Journal of Environmental Agricultural and Food Chemistry, Vol. 8, No. 9, 2009, pp. 818-827.
[18]	H. Lokeshwari and G. T. Chandrappa, “Imapct of Heavy Metal Contamination of Bellandur Lake on Soil and Cultivated Vegetation,” Current Science, Vol. 91, No. 5, 2006, pp. 622-627.