Tracing lead contamination in foods in the city of Kolkata, India

Abstract

Lead isotopic ratios (LIR) of eight common food items, street dust, coal, diesel, sediments, lead ore and rainwater from India have been reported for the first time in this paper. This study characterized the source and extent of lead pollution in the different foodstuff consumed in Kolkata, a major metropolis of eastern India. The atmospheric lead input to the food items, sold openly in busy roadside markets of the city, has been quantified. The mean 207/206 and 208/206 LIRs of the eight food items ranged from 0.8847 to 0.8924 and 2.145 to 2.167, respectively. Diesel had the highest mean 207/206 and 208/206 values of 0.9015 and 2.1869, respectively, apart from the lead ore. The food items had a mean lead concentration between 3.78 and 43.35 mg kg. The two ratio scatter plots of all the different environmental matrices were spread linearly between the uncontaminated Ichapur sediment and diesel. The 207/206 LIRs of the coal with a mean of 0.8777 did not fall in the linear trend, while the street dust and food samples overlapped strongly. The rainwater sample had a 207/206 LIR of 0.9007. Contaminated sediments in Dhapa, the repository of the city's municipal garbage, had a mean 207/206 LIR of 0.8658. The corresponding value obtained from the sewage-fed vegetable grown there was 0.8058. The present study indicated that diesel was one of the main contributor to Pb pollution. The atmospheric lead contribution to the food items was in the range of 68.48-86.66 %.

Sources of atmospheric lead (Pb) in and around an Indian megacity

“…Pb/207 Pb and 208 Pb/207 Pb ratios in Indian coal measured in this study and from a recent publication(Das et al, 2016) have a small range and are similar to those in Australian coal, but the values are slightly higher than Indonesian and Chinese coal…”

“…Two major end members of anthropogenic Pb pollution, Indian coal and road dust as proxy for present-day vehicle emission are also measured. Road dust contains an integration of anthropogenic Pb References: coal (Indian coal-this study and Das et al, 2016;Australian and Indonesian coal -Díaz-Somoano et al, 2009); unleaded gasoline and diesel exhaust (Erel et al, 1997;Geagea et al, 2008;Gioia et al, 2017); Australian and USA ore (Sangster et al, 2000);…”

“…Present day coal-based power generation in India releases approximately 3300 tonnes of Pb per year, and emissions from this source are comparable to those from leaded gasoline exhausts in India in 1990s . Though there has been many studies on the Pb isotopic composition of Chinese coal (Mukai et al, 1993;Zheng et al, 2004;Diaz-Somoano et al, 2009;Cheng and Hu, 2010), data on Indian coal were absent till very recently (Das et al 2016). This study measured Pb isotopic composition of Indian coal from three coal fields, the details of which are documented in the supplementary section (Table S1).…”

Historical documentation of lead toxicity prior to the 20th century in English literature

“…202 Lead contamination of food remains a health issue, particularly for LMICs. [203][204][205][206][207][208] Foods grown in lead-contaminated water also remain a persistent source of lead, indicating the importance of soil remediation in areas with high levels of lead pollution. 209 Additionally, hand-to-mouth activity remains a major route of lead exposure in children from the ingestion of lead-contaminated dust.…”

Use of Radioisotope Ratios of Lead for the Identification of Historical Sources of Soil Lead Contamination in Santa Ana, California

“…This approach to understanding lead source attribution has been applied in prior studies to distinguish between lead originating from leaded gasoline emissions, coal combustion, etc. [20][21][22][23].…”