BRICKS REVEAL RECENT HISTORY OF HEAVY-METAL POLLUTION IN SOIL AROUND A NORTH INDIAN CITY

Up to now, geochemical monitoring of atmospheric heavy metal pollution has been limited to the use of peat, ice deposits and aquatic sedimen ts as sample types. These systems are open, dynamic and easily affecte d by climatic variations. Zn a recent report, Shrivastav et al. (Envir on Mon Ass 1996;40:271-278) have suggested the use of bricks as a geoc hemical monitor of heavy metal fallout and their study has clearly dem onstrated the practical feasibility of the above concept at least in s ome parts of the world. However, more research is required in order to understand the suitability of using bricks as a geochemical monitor o f heavy metal fallout. As part of our continuing research in this dire ction, in this article we report on the history of heavy metal polluti on in the soils of Agra since 1900, that have been traced by analysing bricks of different ages collected from the old buildings/monuments. The study indicated that the soil concentrations of lead, zinc and chr omium rose initially until between 1950 and 1960 and then fell sharply especially over the last 2-3 decades, which can be explained as an ou tcome of socio-economic fluctuations on a local scale and climatic cha nges on a global or regional scale. (C) 1998 Elsevier Science B.V.