kolkata from tollygunge to kidderpore and gariahat to amherst street every time you buy vegetables fish chicken or grocery from roadside markets you are taking home dollops of heavy metal poison in the form of lead a study released by the geological survey of india on sunday highlights the lifethreatening conditions kolkatans face from lead concentration in food far higher than permitted limitsraw food items sold on the streets contain a mean lead concentration between 378 and 4335 mgkg average 2356 mgkg way higher than the threshold value of 25mgkg specified by food safety standards regulation 2011 india the report says about 75 of this lead contamination is contributed by atmospheric lead produced by incomplete diesel combustion it addsthe amount of lead concentration acceptable in the blood of children is 05 mg per litre as against 25 mg per litre in case of adults but in both cases it is accepted that these children or adults are not exposed to excessive environmental sources of leadrandom samples of raw food items like polished rice red lentil masoor dal red spinach chicken fish biscuits spice cumin seeds and medicinal herb tulsi were collected from 12 roadside markets covering north south east and west kolkata soil and vegetable samples were also collected from dhapa along the em bypass for the studystreet dust samples were collected from major roads in north and south kolkata and coal samples were collected from jharia and ranigunj to assess the presence of atmospheric lead from the use of coal galena ore of lead samples were taken from alwar rajasthan to calculate the lead isotopic ratio of indian lead while rain water and diesel samples were collected from the cityall these samples were collected to compare their lead isotopic ratios and lead concentration with that of food items sold on the citys streets to assess contamination in sediments and vegetables found in dhapa soil and vegetable samples were collected from a relatively less polluted place like ichapur about 30km north of kolkatathe maximum lead concentration was found in rice from the markets of kidderpore at 1439 mgkg for red lentil samples the content varied between 182 and 744 mgkg with the maximum found in the markets of tollygunge locallymade snacks had a lead concentration range from 482 to 1071 mgkg with the maximum found in samples from gariahatthe vegetable samples had a range of lead content from a low 328 mgkg to a very high 14547 mgkg in fish samples it ranged from 133 to 1780 mgkg while chicken samples from a market at garden reach had a concentration of 958 mgkg even spices are not free from lead and some samples of cumin jeera seeds collected from markets at tollygunge had a concentration of 3125 mgkgthe most alarming finding came from soil samples at dhapa where a maximum lead content of 80039 mgkg was found at arupota similarly vegetable samples collected from three dhapa sites had an average concentration of 1683 mgkg though ichapur is