Keywords: air pollution, air quality, biomonitoring, enrichment factors, factor analysis, heavy metals, ICP-MS, inductively coupled plasma-mass spectrometry, pollution sources, source apportionment, Lolium multiflorum, biomonitors, airborne trace elements, Italy
Leaves of Lolium multiflorum as indicators of airborne trace element distribution in Central Italy
Ambient air contains particles, ranging from sub-micrometric aerosols to clearly visible dust and sand grains. Plants during evolution developed the ability to maximise light interception and CO2 assimilation and also the efficiency to collect the airborne pollutants. Therefore, plant tissues have been used as indicators of trace elements air pollution. Lolium multiflorum leaves were used as a sampler to describe the distribution of selected elements in the area of Carrara (Tuscany, Central Italy). Unwashed healthy leaves collected in September 2007 from nine sampling sites were analysed by ICP-MS. Enrichment factors (EFs) were calculated taking Al as crustal reference element. Cd and Mo exhibited the highest EFs, with some values above 10,000. Varimax rotated factor analysis identified three main source groups of elements, namely crustal components, marine aerosol spray and anthropogenic sources.