Acumulacion de metales pesados

Archives of Phytopathology and Plant Protection October 2009; 42(10): 956–959

Accumulation of heavy metals in leafy vegetables grown in urban areas by using sewage water and its effect

S. T. GIRISHA1 & VINAY B. RAGAVENDRA2
1 2

Department of Biotechnology, Jana Barathi Campus, Bangalore University, Bangalore, India and Department of Applied Botany & Biotechnology, Mysore University,Mysore-9, India

(Received 13 June 2006)

Abstract In Mysore city, the leafy vegetables which grow by the use of sewage water like Spinacia oleracea (Spinach), Trigonella foenum (Fenugreek), Apium graveolens (Cerery), Mentha silvertrisviridis, Coriander sativum (Coriander) and Amaranths viridi are subjected to the analysis of heavy metals like cadmium, chromium, cobalt, copper, lead, nickel andzinc. Among the six vegetables Mentha silvertrisviridis shows more absorption of heavy metals from sewage water followed by Apium graveolens (Cerery), Spinacia oleracea (Spinach), Trigonella foenum (Fenugreek), Amaranths viridi and Coriander sativum (Coriander) in northerns area of the city,where these heavy metals affect both plants and human beings. The details are discussed in this paper.Keywords: Heavy metals, leafy vegetables, sewage water

Introduction A variety of leaf vegetables are used in a balanced diet (116 g/day) because they are rich in minerals and vitamins A and C. Amongst all types of pollution, agricultural utilization of sewage water in urban cities deserves special attention as it is making the environment quite unsuitable for human health. The impact of sewagewater use has long been recognized as a risk factor for human health. Heavy metals in sewage water are important due to their bioaccumulative nature in various plant parts, adversely affecting plant growth and metabolism; plants which absorb to heavy metals from sewage water stunt grown, and chlorosis, necrosis, leaf epinasty, and discoloration are symptoms of phytotoxicity. Plants are the pathways tomove these heavy metals from water to human beings. The possible adverse effect of heavy metals and their phytotoxic effect have been reported by several workers. Higher concentrations of heavy metals exhibit severe bleaching, reduction in cell size, shrunken chloroplasts, fragmentation, loss of cellular contents, cell lysis, tetrad cells, clumping of cells, etc. The high concentration of heavymetals is due to stagnation of the metals which precipitate out as insoluble metal complexes and which are deposited on the soil

Correspondence: S. T. Girisha, Department of Biotechnology, Jana Barathi Campus, Bangalore University, Bangalore, India. E-mail: stgirishgirish@yahoo.com ISSN 0323-5408 print/ISSN 1477-2906 online ª 2009 Taylor & Francis DOI: 10.1080/03235400701543806

Heavy metalsin leafy vegetables

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surface. Translocation of heavy metals to plants and cow milk is reported by Imam Kasim et al. (1989) and Nambikkairaj et al. (2003). There are several reports regarding heavy metal toxicity; the heavy metals can cause membrane depolarization and acidification of the cytoplasm (Conner & Schimid 2003) and in fact membrane injury is an important effect of metal ions thatmay lead to cellular disruption of homeostasis. Although living organisms need heavy metals for metabolic processes, excess concentrations have a lethal effect. The heavy metals from industry cause serious health problems to human beings (Raje et al. 2005). Techniques for the removal of these heavy metals have been developed by Harshad et al. (2006) (from Medicinal plant Pueraria tuberose)Samanta et al. (2000) (from rice straw), Gupta and Singh (2004) (rice husk), Feroz and Prasad (2005) (coconut shell) and Singh et al. (2005) (wheat bran). Phyto-accumulation of some heavy metals in different parts of some cultivated plants species has been studied by Neelima and Jaganmohan Reddy (2006). Materials and methods The research area chosen for the present study is Mysore City of Karnataka....