Environmental Engineering Reference
In-Depth Information
Benzotriazoles and other benzo-related contaminants are detected in water,
the most common being benzotriazole, tolyltriazole, benzothiazoles, and ben-
zosulfonamides in waters (Richardson and Ternes
2011
; Jover et al.
2009
; van
Leerdam et al.
2009
; Matamoros et al.
2010
). Perfluorinated compounds (PFCs)
include perfluorooctane sulfonate (PFOS), perfluorooctanoic acid (PFOA) and
a number of structurally-related compounds such as fluorinated telomer alco-
hols (FTOHs), perfluorobutanoic acid (PFBA), perfluorohexanoic acid (PFHxS),
Perfluorobutanesulfonate (PFBS), perfluoropropane sulfonate (PFPrS), perfluoro-
ethane sulfonate (PFEtS), perfluorooctane sulfonamide (PFOSA), N-ethyl perfluo-
rooctane sulfonamide acetate (N-EtFOSAA), perfluorododecanoic acid (PFDoDa),
perfluoroundecanoic acid (PFUnDa), perfluorodecanoic acid (PFDA), perfluorono-
nanoic acid (PFNA), perfluoroheptanoic acid (PFHpA), perfluorohexanoic acid
(PFHxA), perfluoropentanoic acid (PFPeA), and perfluoropropanoic acid (PFPrA).
They are mostly volatile and subject to metabolism or degradation that leads to the
formation of their persistent sulfonate and carboxylic acid forms (Richardson and
Ternes
2011
; Andersen et al.
2008
; Farré et al.
2008
; Shi et al.
2008
; Mak et al.
2009
).
Perchlorate is mostly found as an impurity of sodium hypochlorite (liquid bleach)
and as ammonium perchlorate (Richardson and Ternes
2011
). Ionic liquids are com-
posed of cationic or anionic polar headgroups with accompanying alkyl side chains.
The cationic head groups include imidazolium, pyridinium, pyrrolidinium, morpho-
linium, piperidium, quinolinium, quaternary ammonium, and quaternary phosphonium
moieties. The anionic head groups include tetrafluoroborate (BF
4
-
), hexafluoro-
phosphate (PF
6
-
), bis(trifluoromethylsulfonyl)-imide [(CF
3
SO
2
)2 N
-
], dicyanamide
[(CN)
2
N
-
], chloride, and bromide (Richardson and Ternes
2011
; Pham et al.
2010
).
The chemical structures of nanomaterials are highly varied, including fuller-
enes, nanotubes, quantum dots, metal oxanes, TiO
2
nanoparticles, nanosilver, and
zerovalent iron nanoparticles (Richardson and Ternes
2011
). Artificial sweeten-
ers in natural waters mainly include sucralose, acesulfame, cyclamate, saccharin,
aspartame, neotame, and neohesperidin dihydrochalcone (NHDEC) (Richardson
and Ternes
2011
; Scheurer et al.
2009
).
Toxins of blue-green algal origin commonly occur as microcystins, nodularins,
anatoxins, cylindrospermopsin, and saxitoxins, while red tide toxins are detected
as brevetoxins in natural waters (Richardson and Ternes
2011
; dos Anjos et al.
2006
; Wood et al.
2006
; Zhao et al.
2006b
; Smith et al.
2011
). Saxitoxin variants
recorded in cyanobacteria include decarbamoyl derivatives (dc), gonyautoxins
(GTX); neosaxitoxin (neoSTX), N-sulphonocarbamoyl toxins (C-toxins), saxitoxin
(STX) and a class of toxins produced by
Lyngbya wollei
(Humpage et al.
2010
).
Furthermore, chlorination of microcystin-LR and of cylindrospermopsin can give
several byproducts, which are identified as chloro-microcystin, chloro-dihydroxy-
microcystin, dichloro-dihydroxy-microcystin, trichlorohydroxy-microcystin, and
several dihydroxy-microcystins (Merel et al.
2009
).
Endocrine disrupting compounds or chemicals (EDCs) can disrupt the devel-
opment of the endocrine system and of organs that respond to endocrine signals
in organisms. These organisms can be indirectly exposed during prenatal and/or
early postnatal life and the effects of exposure during development are permanent
