title: Fluorescence of leachates from three contrasting landfills.
abstract: Landfill leachates are composed of a complex mixture of degradation products including dissolved organic matter, which includes a wide range of potentially fluorescent organic molecules and compounds. Here we investigate the excitation-emission matrix fluorescence of landfill leachates from three contrasting landfill sites. Landfill fluorescence properties are all characterized by intense fluorescence at lambda(ex) =220-230nm, and lambda(em) =340-370nm which we suggest derives from fluorescent components of the Xenobiotic Organic Matter fraction such as naphthalene, as well as at lambda(ex) =320-360nm, and lambda(em) =400-470nm from a higher molecular weight fulvic-like fraction. Landfill leachates are characterized by intense fluorescence, with approximately 10(2) intensity units of fluorescence at lambda(ex)=220-230nm, and lambda(em)=340-370nmmg(-1) of total organic carbon, demonstrating leachate detection limits of <0.1mgl(-1) total organic carbon. We demonstrate that for all landfill sites, leachate fluorescence intensity has a strong correlation with ground water quality determinants ammonia, total organic carbon and biochemical oxygen demand. We investigate both within-site and between-site leachate fluorescence properties, and demonstrate that although there is significant within-site variability, leachates from all 3 sites can be statistically discriminated using just fluorescence properties (65% success rate) or with a combination of fluorescence and basic geochemical parameters (85%). Our findings suggest that fluorescence can be used as a rapid and sensitive tracer of leachate contamination of ground water, as well as help discriminate, together with geochemical determinants, leachates from different landfill sources.
authors.affiliation: School of Geography, Earth and Environmental Sciences, The University of Birmingham, Edgbaston, Birmingham B15 2TT, UK. a.baker.2@bham.ac.uk
authors.forename: Andy
authors.initials: A
authors.lastname: Baker
authors.forename: Michael
authors.initials: M
authors.lastname: Curry
mesh_terms: D000641:Ammonia / Q000737:chemistry; D002244:Carbon / Q000737:chemistry / Q000378:metabolism; D005843:Geography; D009930:Organic Chemicals / Q000032:analysis; D010100:Oxygen / Q000737:chemistry; D025341:Principal Component Analysis; D012037:Refuse Disposal; D012989:Soil Pollutants / Q000633:toxicity*; D013050:Spectrometry, Fluorescence; D014874:Water Pollutants, Chemical / Q000032:analysis*; D014881:Water Supply; D015262:Xenobiotics / Q000032:analysis / Q000378:metabolism
chemical_list: D009930:Organic Chemicals; D012989:Soil Pollutants; D014874:Water Pollutants, Chemical; D015262:Xenobiotics; D002244:Carbon; D000641:Ammonia; D010100:Oxygen