Journal of Horticultural Sciences

L. R. Varalakshmi ¹, A. N. Ganeshamurthy ¹

Affiliations
1 Division of Soil Science and Agricultural Chemistry, Indian Institute of Horticultural Research, Hessaraghatta Bangalore- 560 089, IN

Abstract

A study was conducted in peri-urban Bangaluru (where city wastewater from four water bodies, viz., Bellandur, Varthur, Byramangala and Nagavara tanks, is being used for cultivation of vegetable crops) to assess heavy metal contamination in water, soil and vegetable samples. Analyses revealed that concentration of cadmium (Cd) and chromium (Cr) in waters from all the tanks exceeded recommended levels of 0.01 and 0.1 mg/l, respectively, while content of lead (Pb) and nickel (Ni) are within safe limits. Concentration of Cd was highest in the water of Bellandur tank (0.039 mg/ l) and of Cr was highest in the water of Byramangala tank (0.311 mg/l). Bellandur and Varthur tanks were found highly contaminated with Cd, Pb and Ni. Mean concentration of heavy metals in soils receiving sewage water from the four tanks ranged from 1.92 to 2.9 mg/kg for Cd, 47.04 to 68.12 mg/kg for Pb, 35.08 to 92.78 mg/kg for Cr and 48.2 to 57.3 mg/kg for Ni. Cd and Pb content were highest in soils around Varthur and Bellandur tanks, while, mean concentration of Cr was highest in soils around Byramangala tank. Similar trends were observed for heavy metal content in vegetables. Among the vegetables studied, leafy vegetables accumulated higher concentration of heavy metals, followed by ischolar_main vegetables. Cd concentration in all the vegetables grown around Varthur and Bellandur tanks exceeded the safe limit prescribed under Prevention of Food Adulteration Act (PFA 1954). Pb and Ni concentration exceeded safe limits in all the vegetables in all the tank areas studied.

Keywords

Heavy Metals, Peri-Urban, Water Bodies, Soils, Vegetables.

Full Text

   

A. N. Ganeshamurthy ¹, L. R. Varalakshmi ¹, H. P. Sumangala ²

Affiliations
1 Division of Soil Science and Agricultural Chemistry, Indian Institute of Horticultural Research, Hessaraghatta Lake Post, Bangalore-560 089, IN
2 Division of Ornamental Crops, Indian Institute of Horticultural Research, Hessaraghatta Lake Post, Bangalore-560 089, IN

Abstract

The India's population living in cities and urban areas has doubled to 27.8% since Independence. Our cities face enormous challenges of environmental pollution and health related problems. City authorities have often been reluctant to accept urban and periurban agriculture because of perceived health risks. Nevertheless, in most cities the world over, periurban agriculture is practiced on a substantial scale, despite prohibitive laws and regulations. Non-degradable pollutants added to the system through anthropogenic activities like heavy metals in air, soil, water and crops bother us more than others as these tend to bio-accumulate. Throughout history, heavy metal contamination has long plagued mankind - undermining intelligence and causing debasing behaviour. Toxicity of some of the heavy metals even leads to deficiency of essential metals like Zn, Cu, etc. in both human and animals. Climate, nutritional status, genetic predisposition, type of work and exposure level influence the intensity of impact on health. Permissible levels prescribed by different organizations differ because of differences in tolerance levels of people of different origins and differences in threat perception of the people. With our current level of knowledge a permanent and foolproof method to stop entry of heavy metals into the food chain is impossible. However, methods are available to reduce intensity of the effects. Alternative land use with crops not directly consumed by human beings and animals offers a better remedy to contain heavy metal entry into food chain. India has a wide ranging set of environmental laws that lay down norms for air, water, soil, wastes, etc. Legislative frame work has been developed in the belief that a policing model is sufficient. It does not go beyond that. Regulatory mechanisms may not be effective in isolated cases but are essential drivers to augment other approaches, by putting a "cap" on the level of degradation that is socially acceptable, as well as creating space for other, cleaner and more acceptable alternatives to be "viable".

Keywords

Environmental Risk, Heavy Metal Contamination, Periurban Agriculture.

Full Text

   

L. R. Varalakshmi ¹, A. N. Ganeshamurthy ¹

Affiliations
1 Division of Soil Science and Agricultural Chemistry, Indian Institute of Horticultural Research, Hessaragtatta Lake Post, Bangalore - 560 089, IN

Abstract

Vegetable samples from one of the main whole sale markets of Bangalore city were collected over two years and analysed for heavy metals such as Cd, Pb, Cr and Ni. Heavy metal content of vegetables ranged from 0.24 to 2.54 mg Cd kg^-1, 2.16 to 10.40 mg Pb kg^-1, 3.08 to 16.2 mg Cr kg^-1 and 1.66 to 11.52 mg Ni kg^-1. Leafy vegetables accumulated higher concentration of heavy metals followed by ischolar_main vegetables. Fruit vegetables accumulated the lowest content of heavy metals. But the heavy metal content of all the vegetables crossed the safe limits permitted for human consumption to a far greater extent except that Cd content of ischolar_main and fruit vegetables were within the safe levels. Among leafy vegetables, amaranthus and palak accumulated the highest content of all the four heavy metals studied.

Keywords

Heavy Metals, Contamination, Market Samples and Vegetables.

Full Text