 Parts of Varanasi are contaminated with industrial chemicals including toxic heavy metal . Studies of wastewater from Varanasi 's sewage treatment plants identify that water 's contamination with metals and the reuse of this water for irrigation as a way that the toxic metals come to be in the plants that people grow for food . One studied example is palak , a popular leafy vegetable which takes up heavy metal when it is in the soil , and which people then eat . Some of the polluting sludge contains minerals which are fertiliser , which could make polluted water attractive to use . Pesticides used in local farming are persistent enough to be spread through the water , to sewer treatment , then back to the farms as wastewater . 
 Parts of Varanasi are contaminated with industrial chemicals including toxic heavy metal . Studies of wastewater from Varanasi <a href='null_genetive' title='1'><mark>'s</mark></a>sewage treatment plants identify that water <a href='null_genetive' title='2'><mark>'s</mark></a>contamination with metals and the reuse of this water for irrigation as a way <a href='null_relcl' title='3'><mark>that</mark></a>the toxic metals come to be in the plants <a href='null_relcl' title='4'><mark>that</mark></a>people grow for food . One studied example <a href='drop_aux' title='5'><mark>is</mark></a>palak , a popular leafy vegetable which <a href='uninflect' title='6'><mark>takes</mark></a> up heavy metal when it <a href='drop_aux' title='7'><mark>is</mark></a>in the soil , and which people then eat . Some of the polluting sludge <a href='uninflect' title='8'><mark>contains</mark></a> minerals which <a href='drop_aux' title='9'><mark>are</mark></a>fertiliser , which could make polluted water attractive to use . Pesticides used in local farming <a href='drop_aux' title='10'><mark>are</mark></a>persistent enough to be spread through the water , to sewer treatment , then back to the farms as wastewater . 
Parts of Varanasi r contaminated with industrial chemicals including toxic heavy metal . Studies of wastewater from Varanasi  sewage treatment plants identify that water  contamination wid metals and the reuse of dis water fir irrigation as a way the toxic metals come to b in the plants bitches grow fir food . One studied example palak , a popular leafy vegetable which take up heavy metal when it in the soil , and which people then eat . Some of the polluting sludge contain minerals which fertiliser , which could make polluted water attractive to use . Pesticides used in local farming persistent enough to be spread through the water , to sewer treatment , then bak to the farms as wastewater .