FORMATE AND ACETATE LEVELS COMPARED IN MONSOON AND WINTER RAINWATER AT DAYALBAGH, AGRA (INDIA)

A total of 59 rainwater samples were collected during the winter and m onsoon (1991-92) at Dayalbagh, Agra. This site is relatively free from the influence of anthropogenic emissions and the volume-weighted aver age concentrations (VWA) of formate in the winter and monsoon were 22. 5 +/- 6, 16.1 +/- 3 while acetate VWAs were 17.1 +/- 5 and 13.8 +/- 3 mu mol l(-1),respectively. Although the VWAs varied between seasons, i t was not statistically different. Total deposition (in mmol m(-2)) va ried between season (winter formate, 1.4; acetate, 1.1; monsoon format e, 7.4; acetate, 6.4). A difference in VWA values may have occurred as a result of the dilution factor; the total rain depth from collected samples in the monsoon was 46 cm while that in winter was 6.3 cm. Sour ces at this site may be anthropogenic and natural; scavenging from the vapour phase, washout of soil particles and emissions from vegetative sources are probably important sources for formate and acetate.