Status of Cadmium Concentration in Soil and Vegetable Irrigated with City Effluent

Cadmium is a toxic and carcinogenic element1].In the1950s and 1960s,cadmium intoxication was considered to bestrictly an occupational disease.It was not until recognition of thecontribution of cadmium exposure to the etiology of Itai-itai dis-ease.It is …

Status of Cadmium Concentration in Soil and Vegetable Irrigated with City Effluent

Cadmium(Cd) is a toxic and carcinogenic element,and it causes different diseases for people like sever nausea,salivation vomiting,diarrhoea,abdominal pain and neuralgia when it comes into food chain at excessive concentration.It is also not included in the micronutrients for plant growth.Due to arid and semi arid conditions of Pakistan,rainfall is small,causing shortage of irrigation water.Because of this shortage,farmers largely use city effluents for raising vegetables in the areas around big cities,which are contaminated with industrial wastewater.The effluents from Pakistan third largest city(Faisalabad) are used as supplementary irrigation water to produce vegetables for human consumption.This paper reports a study on assessment of risks and opportunities associated with this practice,with emphasis on Cd,which can enter the food chain as an impurity in vegetables.Cd and other elements were measured in some typical effluents,four types of soils and many vegetables with no fertilizer application.It was found that the municipal effluents increased soil salinity,sodicity and Cd concentration.The Cd concentration in the vegetables was high above those normally associated with suitability for human consumption.There were suggestions that soluble Cd concentration in the effluents could be lessened by adding lime,concurrently lowering the sodium adsorption ratio and residual sodium carbonate of the effluents,thus making them safe for utilization on agricultural soils.(Fig 1),Tab 7,Ref 23