Confirming anthropogenic influences on the major organic and inorganic constituents of rainwater in an urban area

Abstract

Abstract. The chemical composition and organic compounds of rainwater were investigated from June to December 2012 at Gwangju in Korea. The volume weighted mean of pH ranged from 3.83 to 8.90 with an average of 5.78. 50 % of rainwater samples had pH values below 5.6. The volume-weighted mean concentration (VWMC) of major ions followed the order: Cl− > SO42− > NH4+ > Na+ > NO3− > Ca2+ > Mg2+ > K+. The VWMC of trace metals decreased in the order as follows Zn > Al > Fe > Mn > Pb > Cu > Ni > Cd > Cr. The VWMCs of major ions and trace metals were higher in winter than in summer. The high enrichment factors indicate that Zn, Pb, Cu, and Cd originated predominantly from anthropogenic sources. Factor analysis (principal component analysis) indicates the influence of anthropogenic pollutants, sea salt, and crustal materials on the chemical compositions of rainwater. Benzoic acids, 1H-Isoindole-1,3(2H)-dione, phthalic anhydride, benzene, acetic acids, 1,2-benzenedicarboxylic acids, benzonitrile, acetaldehyde, and acetamide were the most prominent pyrolysis fragments for rainwater organic compounds identified by pyrolysis gas chromatography/mass spectrometry (Py-GC/MS). The results indicate that anthropogenic sources are the most important factors affecting the organic composition of rainwater in urban area.

Changes on wet deposition of major organic and inorganic ions in subtropical region of Brazil

“…Comparison of pH and Volume-Weighted Mean (VWM) concentration of ionic and organic components of rainwater from different places in the world . This study; b(Pelicho et al, 2006); c(Hu et al, 2003); d(Masood et al, 2018); e(Niu et al, 2018); f(Chon et al, 2015); g(Zhang et al, 2011); …”