Heavy Metal Contaminated Food Crops Irrigated with Wastewater in Peri Urban Areas, Zambia

Evaristo Mwaba Kapungwe

Geography Department, University of Zambia, Lusaka, Zambia.

DOI: 10.4236/ojmetal.2013.32A1010                

Abstract

Studies on peri urban farming in Zambia have not adequately tackled the issues pertaining to heavy metal contaminated wastewater irrigation farming. The study investigated heavy metal contamination of water, soils and crops at two peri urban areas in Zambia. Two study sites were New Farm Extension in Mufulira Town in the Copperbelt Province and Chilumba Gardens in Kafue Town in Lusaka Province. The heavy metals investigated were lead, copper, cobalt, nickel and chromium. These heavy metals were found to be higher than acceptable limits in wastewater used to irrigate crops and there are potential human health risks associated with consumption of heavy metal contaminated food crops which have implications on the livelihoods of people. Samples of water, soil and crops were collected and analysed for lead (Pb), copper (Cu), chromium (Cr), cobalt (Co) and nickel (Ni) using the Atomic Absorption Spectrometer (AAS). The data on heavy metals was analysed using mean, standard error and T-test. The results indicated that the levels of heavy metals in wastewater, soil and food crops were above acceptable limits at two study sites. It can be concluded that there was heavy metal contamination of wastewater, soil and food crops at the two peri-urban areas in Zambia. The study highlighted the actual levels of heavy metal contaminant uptake in food crops consumed by the peri urban population. The information from this study can be used by the relevant authorities to develop appropriate measures for monitoring and control of heavy metal contamination in wastewater irrigation farming systems in peri urban areas inZambia.

Keywords

Heavy Metal Contamination; Wastewater; Soils; Food Crops; Irrigation Farming; Peri Urban Areas; Zambia

Conflicts of Interest

The authors declare no conflicts of interest.

References

[1]	J. Parkinson and K. Tayler, “Decentralized Wastewater Management in Peri-Urban Areas in Low-Income Countries,” Environment and Urbanization, Vol. 8, No. 1, 2003, pp. 75-89.
[2]	E. Obuobie, B. Keraita, G. Danso, P. Amoah, O. Cofie, L. Raschid-Sally and P. Drescher, “Irrigated Urban Vegetable Production in Ghana: Characteristics, Benefits and Risks,” International Water Management Institute, Accra, 2006.
[3]	S. Buechler, W. Hertog and R. Van Veenhuizen, “Wastewater Use for Urban Agriculture,” Urban Agriculture Magazine, No. 8, 2002, pp. 1-4.
[4]	L. Raschid-Sally and P. Jayakody, “Drivers and Characteristics of Wastewater Agriculture in Developing Countries-Results from Global Assessment,” Water Management Institute (IWMI), Stockholm, 2008.
[5]	M. B. Pescod, “Wastewater Treatment and Use in Agriculture,” FAO Irrigation and Drainage Paper 47, Rome, 1992.
[6]	S. Buechler, G. Devi and L. Raschid, “Livelihoods and Wastewater Irrigated Agriculture: Musi River in Hyderabad City, Andhra Pradesh, India,” Urban Agriculture Magazine, No. 8, 2002, pp. 14-17.
[7]	J. Kaspersma, “Electronic Conference: Agricultural Use of Untreated Urban Wastewater in Low Income Countries,” Urban Agriculture Magazine, No. 8, 2002, pp. 5-6.
[8]	P. Dreschel, U. J. Blumanthal and B. Keraita, “Balancing Health and Livelihoods: Adjusting Wastewater Irrigation Guidelines for Resource Poor Countries,” Urban Agriculture Magazine, No. 8, 2002, pp. 7-9.
[9]	M. Dubbeling, “Policy Brief: Treatment and Use of Waste-water in Urban Agriculture,” Urban Agriculture Magazine, No. 8, 2002, p. 41.
[10]	S. Guendel, “Livestock and Urban Waste in East Africa,” Urban Agriculture Magazine, No. 8, 2002, p. 42.
[11]	L. Chibesa, S. Mukuka, H. A. Mwankanye, J. Nsowela, L. Sakanta and D. Shebele, “Small Scale Cultivation around Kalingalinga,” In: L. Van Den Berg, Ed., In the Shadow of Lusaka: Studies in Zambian Society Number 6, University of Zambia, Lusaka, 1982, pp. 13-21.
[12]	K. V. Kalumba, “Ten Case Studies of Small Scale Gardening in Thornpark-Villa Elizabetta Area of Lusaka,” In: L. Van Den Berg, Ed., In the Shadow of Lusaka: Studies in Zambian Society Number 6, University of Zambia, Lusaka, 1982.
[13]	M. N. Saasa, “Uses of Vacant Land in Kaunda Square-Munali Area of Lusaka,” In Van Den Berg, L. Ed., In the Shadow of Lusaka: Studies in Zambian Society Number 6, University of Zambia, Lusaka, 1982.
[14]	L. van den Berg, Ed., In the Shadow of Lusaka: Studies in Zambian Society Number 6, University of Zambia, Lusaka, 1982.
[15]	D. Jaeger and J. D. Huckabay, “The Garden City of Lusaka: Urban Agriculture,” In G. F. Williams, Ed., Lusaka and Its Environs: A Geographical Study of a Planned Capital in Tropical Africa, Zambia Geographical Association, Handbook Series No. 9, University of Zambia, Lusaka, 1986, pp. 266-277.
[16]	M. C. Mulenga, “Peri-Urban Farming: A Study of Agriculture under Pressure of Urban Growth in Lusaka, Zambia,” Ph.D. Dissertation, University of London, London, 1991.
[17]	M. C. Mulenga and A. Dubresson, Eds., Proceeding of International Symposium on Government, Governance, Urban Territories in Southern Africa, University of Zambia, Lusaka, 21-22 November 2001.
[18]	M. C. Mulenga, “Peasant Cultivation in and around the Municipal Area of Chipata,” In M .C. Mulenga and A. Dubresson, Eds., Proceeding of International symposium on Government, Governance, Urban Territories in Southern Africa, University of Zambia, Lusaka, 21-22 November, 2001, pp. 81-95.
[19]	B. Marshall, T. Bowyer-Bower, B. H. Chishala, E. M. Kapungwe, M. Agrawal, R. Agrawal, D. Lintelo, J. Holden, M. Macwani, J. Volk, V. Krishnan and R. Sharma, “Contaminated Irrigation Water and Food Safety for the Urban and Peri-Urban Poor: Appropriate Measures for Monitoring and Control from Field Research in India and Zambia,” Main Inception Report: Department for International Development (DFID) Project No. R8160, Department for International Development (DFID-UK), London, 2004.
[20]	B. Sanyal, “Urban Agriculture: Who Cultivates and Why? A Case-Study of Lusaka, Zambia,” Food and Nutrition Bulletin, Vol. 7, No. 3, 1985, pp. 15-24.
[21]	C. Rakodi, “Urban Agriculture—Research Questions and Zambian Evidence,” Journal of Modern African Studies, Vol. 26, No. 3, 1988, pp. 495-515. doi:10.1017/S0022278X00011745
[22]	G. Hampwaye, E. Nel and C.M. Rogerson,, “Urban agriculture as local initiative in Lusaka, Zambia,” Environment and Planning C: Government and Policy, Vol. 23, 2007, pp. 553-572. doi:10.1068/c7p
[23]	M. Gabi and J. S. Simwinga, “Future Development of Vacant Land in and around Lusaka,” In: L. Van Den Berg, Ed., In the Shadow of Lusaka: Studies in Zambian Society Number 6, University of Zambia, Lusaka, 1982, pp. 1-12.
[24]	T. Sinkala, L. Kanyomeka, S. Simukanga, M. Mwasa, O. N. Sikazwe, C. M. Nsomi, E. T. Mwase-Ngulube, M. Lewanika, E. Kasuta, M. S. Mwala and M. M. Musonda, “Control of Aquatic Weeds in Kafue River. Phase1: Environmental Impact Assessment of the Kafue River Basin between Itezhi-Tezhi Dam and Kafue Gorge,” Ministry of Environment and Natural Resources, Lusaka, 1998.
[25]	T. Sinkala, “State of Water Quality of Kafue River 1971-1997: Literature Review,” Environmental Council of Zambia, Lusaka, 1998.
[26]	E. M. Kapungwe, “Industrial Land Use and Heavy Metal Contaminated Wastewater Used for Irrigation in Peri-Urban Zambia,” Singapore Journal of Tropical Geography, Vol. 32, No. 1, 2011, pp. 71-84. doi:10.1111/j.1467-9493.2011.00422.x
[27]	A. K. Gupta and M. L. Varshney, “Practical Manual for Agricultural Chemistry,” Kalyani, New Delhi, 1989.
[28]	D. J. Reuter, J. B. Robinson, K. I. Peverill and G. H. Price, “Guidelines for Collecting, Handling and Analysis of Plant Materials,” In: D. J. Reuter and J. B. Robinson, Eds., Plant Analysis: An Interpretation Manual, Inkata Press, Melbourne, 1986.
[29]	Y. P. Kalra and D. G., Maynard, “Methods Manual for Forest Soil and Plant Analysis,” Northern Forestry Centre, Edmonton, 1991.
[30]	R. D. E. Bake and M. C. Amacher, “Nickel, Copper, Zinc and Cadmium,” In: A. L. Page, R. H. Miller and D. R. Reeney, Eds., Methods for Soil Analysis, American Society of Agronomy, Madison, 1982.
[31]	R. G. Burau, “Lead,” In: A. L. Page, R. H. Miller and D. R. Reeney, Methods for Soil Analysis, American Society of Agronomy, Madison, 1982.
[32]	H. M. Reisenaurer, “Chromium,” In A. L. Page, R. H. Miller and D. R. Reeney, Methods for Soil Analysis, American Society of Agronomy, Madison, 1982.
[33]	J. Kubota and E. E. Cary, “Cobalt, Molybdenium and Selenium,” In: A. L. Page, R. H. Miller and D. R. Reeney, Methods for Soil Analysis, American Society of Agronomy, Madison, 1982.
[34]	E. van Ranst, M. Verloo, A. Demeyer and J. M. Pauwels, “Manual for the Soil Chemistry and Fertility Chemistry,” University of Ghent, Gent, 1999.
[35]	D. Ebdon, “Statistics in Geography,” Basil Blackwell, Oxford, 1985.
[36]	C. Bless and R. Kathuria, “Fundamentals of Social Statistics: An African Perspective,” Juta and Company, Cape Town, 1993.
[37]	R. S. Ayers and D. W. Westcot, “Water Quality for Agriculture,” Food and Agriculture Organisation, Rome, 1985.
[38]	P. Papapreponis, R. Robertson, M. Roworth, S. A. Ogston and F. L. R. William, “Levels of Inorganics and Organics in Soils: When Is High, High?” Environment and Health International, Vol. 8, No. 1, 2006, pp. 4-12.
[39]	Department of Environment, Food and Rural Affairs-United Kingdom, DEFRA Report Series on Soil Guideline Values, DEFRA, London, 1989.
[40]	Department of Environment, Food and Rural Affairs-United Kingdom), DEFRA Report Series on Soil Guideline Values, DEFRA, London, 2002.
[41]	Government of Republic of Zambia, “The Food and Drugs Act,” Laws of the Republic of Zambia, Act No 17, 1995.
[42]	FAO/WHO, Joint FAO/WHO Expert Committee on Food Additives (JECFA) FAO, Rome, 2002.
[43]	European Commission, “Commission Regulation (EC) 466/2001: Setting Maximum Levels for Certain Contaminants in Foodstuffs,” Official Journal of the European Communities, Brussels, 2001.
[44]	United Kingdom Regulation, Statutory Instrument 1989 No. 1263 Sludge (Use in Agriculture) Regulation, Ministry of Agriculture Food and Fisheries, London, 1989.
[45]	D. L. Lake, “Chemical Speciation of Heavy Metals in Sewage Sludge and Related Matrices,” In: J. N. Lester, Ed., Heavy Metals in Wastewater and Sludge Treatment Process, CRC Press Inc, Boca Raton, 1987.
[46]	Ministry of Environment (Ontario Canada), “Green Facts: Cobalt in the Environment,” 2011. http://www.archive.org/greenfactscobalt
[47]	M. Muchuweti,, J. W. Birkett, E. Chinyanga, R. Zvauya, M. D. Scrimshaw and J. N. Lester, “Heavy Metal Content of Vegetables Irrigated with Mixtures of Wastewater and Sewage Sludge in Zimbabwe: Implications for Human Health,” Agriculture, Ecosystems & Environment, Vol. 112, No. 1, 2006, pp. 41-48. doi:10.1016/j.agee.2005.04.028
[48]	S. Simukanga, V. Shitumbanuma and T. Kalinda, “Impacts of Mining Effluents on the Water Quality, Sediments, Soils and Crops in the Mwambashi Catchment Area of the Copperbelt of Zambia,” Ministry of Tourism, Environment and Natural Resources Pilot Environmental Fund, Lusaka, 2002.
[49]	S. C. Maree, “Soil,” In: F. Mendelssohn, Ed., The Geology of the Northern Rhodesian Copperbelt, MacDonald and Company, London, 1961.
[50]	V. Shitumbanuma and J. M. Tembo, “Characterization of Soils at No.1 Nkana Cobalt Plant, OBD 53 and the Mwekera Area in Kitwe, Zambia: A Report for ZCCM Investment Holding Plc,” University of Zambia, Lusaka, 2006.
[51]	S. Khan, Q. Cao and Y. M. Zheng, Y. Z. Huang and Y. G. Zhu, “Health Risks of Heavy Metals in Contaminated Soils and Food Crops Irrigated with Wastewater in Bei-jing, China,” Environmental Pollution, Vol. 152, No. 3, 2008, pp. 686-692. doi:10.1016/j.envpol.2007.06.056
[52]	R. J. Hobbs and B. Streit, “Heavy Metal Concentrations in Plants Growing on a Copper Mine Spoil in the Grand Canyon, Arizona,” American Midland Naturalist, Vol. 115, No. 2, 1986. pp. 277-281. doi:10.2307/2425864
[53]	F. Gharbi, S. Rejeb, M. H. Ghorbal and J. L. Morel, “Plant Response to Copper Toxicity as Affected by Plant Species and Soil Type,” Journal of Plant Nutrition, Vol. 28, No. 3, 2009, pp. 379-392. doi:10.1081/PLN-200049147
[54]	J. I. Nirmal Kumar, H. Soni, R. N. Kumar and I. Bhatt, “Hyper Accumulation and Mobility of Heavy Metals in Vegetable Crops in India,” The Journal of Agriculture and Environment, Vol. 10. No. 29, 2009, pp. 29-38.
[55]	Times of Zambia, “Mufulira Water Contaminated,” Chishimba C., 3 January 2008.
[56]	Times of Zambia, “Mine Water Pollution Cases Need Decisive Measures,” Mulenga N., 11 January 2008.
[57]	R. J. Sharma, M. Agrawal and F. Marshall, “Heavy Metal Contamination of Soil and Vegetables in Suburban Areas of Varanasi, India,” Ecotoxicology and Envrionmental Safety, Vol. 66, No. 2, 2007, pp. 258-266. doi:10.1016/j.ecoenv.2005.11.007
[58]	A. Behbahaninia and S. A. Mirbagheri, “Investigation of Heavy Metals Uptake by Vegetable Crops from Metal Contaminated Soil,” World Academy of Science, Engineering and Technology, Vol. 45, 2008, pp. 56-58.