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efficiency gains, particularly with respect to aeration (Ahmad and Reynolds, 1998). A num-
ber of articles by Ahmad and Reynolds (Ahmad and Reynolds, 1995 , 1999 ; Reynolds and
Ahmad, 1997 ; Reynolds, 2002 ) have determined that a decrease in normalized fluores-
cence intensities of peak T is observed from influent to effluent across a treatment process.
Peak T at λ ex = 280 and λ em = 340 nm was identified as being most likely to relate to the
biodegradable material. This phenomenon has been utilized by other researchers investi-
gating wastewater treatment processes such as sludge dewatering (Yu et al., 2010 ), landfill
leachates (Lu et al., 2009 ), membrane fouling (Moon et al., 2010 ), membrane bioreactors
(Wang et al., 2009 ), organic matter removal via coagulation-flocculation processes (Gone
et al., 2009 ) and the composting of municipal waste (He et al., 2011 ). Two of the key issues
surrounding the analysis of wastewater samples using fluorescence spectroscopy are the
correction for inner filter effects due to the highly absorbing nature of the samples and tur-
bidity. Correction and normalization of fluorescence data are covered in Chapters 1 and 7,
and more specifically the inner filter effects exhibited in wastewater samples is discussed
by Reynolds and Ahmad ( 1997 ), Ahmad and Reynolds ( 1999 ), and Reynolds ( 2002 ).
A summary of the significant research that has established correlations between fluo-
rescence and wastewater quality parameters over the last 25 years is shown in Table 3.3 .
What is evident from previous work is that strong correlations do exist between traditional
water quality parameters and fluorescence, although there are issues with directly compar-
ing fluorescence data between geographical locations and between sites. More recent lit-
erature (Hudson et al., 2007 , 2008 ) indicates that future research should focus on utilizing
and analyzing fluorescence measurements as a direct and independent parameter for water/
wastewater quality, rather than as a surrogate for specific water quality parameters. It is
widely accepted that further research is required to investigate fully the effects of advanced
treatment process on peaks T and C, especially if fluorescence-based techniques are to be
applied to wastewater treatment processes and the tracing of DOM within wastewater dis-
tribution systems.
3.5.2 Drinking Water Fluorescence
In comparison to wastewaters, the application of fluorescence spectroscopy for the detec-
tion and monitoring of organic matter (OM) in drinking water sources and water distribution
and water systems is an emerging discipline. Organic matter, both dissolved (DOM) and
natural (NOM), is ubiquitous in all waters that are used to supply drinking water systems
(Matilainen et al., 2011 ). Even so, the recent advances of fluorescence-based techniques
are sufficiently mature so as to be considered an alternative approach to more conventional
methods for the characterization of DOM and/or NOM in drinking water systems. In a
recent review by Matilainen et al. ( 2011 ), a comprehensive overview of current methods
that are used to characterize NOM in relation to drinking water treatment, including fluo-
rescence, is provided. Early work (Rosario-Ortiz et al., 2007 ) applied the use of EEMs
as a tool for characterizing OM (inclusive of DOM or NOM) in drinking water sources.
DOM characterization in drinking water sources is important, as it is known that DOM
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