Environmental Engineering Reference
In-Depth Information
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