Environmental Engineering Reference
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by nocturnal cooling in the upper ocean and can transport significant amounts of
H 2 O 2 to deep waters (Johnson et al. 1989 ; Sarthou et al. 1997 ; Scully and Vincent
1997 ; Yuan and Shiller 2001 ). (viii) H 2 O 2 is thought to play an important role in
the occurrence of photosynthesis in higher plants (Komissarov 1994 , 1995 ; 2003 )
and in natural waters (Mostofa et al. 2009a , b ), by which effect it can induce the
production of autochthonous DOM in the aqueous environment. (ix) H 2 O 2 can
react with CO 2 under irradiation to produce various organic substances in aqueous
solution (Lobanov et al. 2004 ), with a potentially significant role in biogeochemi-
cal processes in natural waters. (x) H 2 O 2 plays an important role in controlling
the physiology of plants, including the activity of some enzymes and the pho-
tophosphorylation and photorespiration rates; it is also responsible for fungitoxic-
ity of the leaf surface (Lobanov et al. 2008 ). (xiii) H 2 O 2 is generated inside cells
by peroxisomes and mitochondria; the formation of H 2 O 2 is caused by the reduc-
tion of O 2 absorbed in intracellular fluid during the photorespiration (Komissarov
2003 ; Lobanov et al. 2008 ). (xiii) H 2 O 2 acts as an oxidant in the conversion of SO 2
to SO 4 2 in rainwater, thereby contributing to the acid rain phenomenon that is
a harmful threat which damages plant tissues and contributes to forest decline
worldwide (Calvert et al. 1985 ; Sakugawa et al. 1990 , 1993 ). (xiii) The environ-
mental concentration of H 2 O 2 is influenced by algae, which simultaneously cause
its decay and induce its photoinduced production by exposure of algal suspensions
to sunlight (Zepp et al. 1987 ). (xiv) The photoinduced generation of H 2 O 2 from
algal suspensions plays a key role in the oxidation of anilines; the latter are able to
decrease H 2 O 2 production, possibly by consuming it on the surface of algal cells
(Zepp et al. 1987 ; Zepp and Schlotzhauer 1983 ). (xv) Elevated levels of H 2 O 2
induce damage and cell lysis in microorganisms (Gonzalez-Flecha and Demple
1997 ; Weinbauer and Suttle 1999 ); H 2 O 2 is also implicated as a cause of mortal-
ity of fecal indicator bacteria in marine sewage fields (Mitchell and Chamberlin
1975 ; Clark et al. 2008 ). (xvi) Bioelectrochemical oxidation of wastewater organic
matter can effectively produce H 2 O 2 on an industrial scale, with an overall 83 %
efficiency that could be useful for industrial purposes (Rozendal et al. 2009 ). (xvii)
H 2 O 2 produced from DOM may contribute approximately 1-50 % of hydroxyl
radical (HO
), a strong oxidizing agent, which is responsible for indirect photoin-
duced changes in the DOM components in natural waters (Mostofa and Sakugawa
2009 ; Takeda et al. 2004 ; Nakatani et al. 2007 ; Page et al. 2011 ).
1.2 Organic Peroxides (ROOH) and Their Biogeochemical
Functions
Organic peroxides (ROOH) are organic compounds containing the peroxide func-
tional group (-O-O-), and may be considered as derivatives of hydrogen perox-
ide (H-O-O-H) where one or both of the hydrogen atoms have been replaced by
organic radicals. Organic peroxides can commonly be denoted as ROOH, where
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