Environmental Engineering Reference
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(Lalah et al.
2003
), but was likely overestimated because metabolites were not
separated from the
14-
C CPY. The DT
50dis
values measured in pore-water ranged
from 7 to 14 d in water-gravel laboratory-based microcosms that were treated with
0.2-20 μg CPY L
−1
(Pablo et al.
2008
). The mean and geometric mean DT
50dis
s for
CPY in laboratory and microcosm tests were 68 and 39 d, respectively (SI Table
4
).
5
Fate in Organisms
The fate of CPY in organisms is a function of absorption, distribution, metabolism
and excretion (ADME) and has been well studied in mammals (Testai et al.
2010
).
Observations have also been recorded for other animals such as fish (Racke
1993
;
Barron and Woodburn
1995
), aquatic organisms (Giesy et al.
1999
) and birds
(Solomon et al.
2001
). The focus in this paper is on newer studies, and only key
information from older studies will be addressed. Integration of the processes of
ADME in organisms at quasi-equilibrium is described by several factors, which are
ratios between abiotic and biotic compartments. These include bioconcentration
factors (BCF), bioaccumulation factors (BAFs), biota/sediment accumulation fac-
tors (BSAFs) and, in the case of movement in the food web, biomagnification
(BMFs) or trophic magnification factors (TMFs) (Gobas et al.
2009
).
Several studies have been conducted in aquatic organisms to measure concentra-
tions of CPY in fish and other organisms during uptake, at equilibrium, and during
dissipation. These have been used to calculate various magnification factors.
Bioconcentration factors (BCFs) reported from laboratory studies reviewed by Racke
(
1993
) and Barron and Woodburn (
1995
) in 17 species of freshwater (FW) and salt-
water fish exposed to CPY at concentrations <10 μg/L for ≥26 d ranged from 396 to
5,100 with a mean of 1,129 and a geometric mean of 848 (SI Table
5
). Similar values
were observed in several studies conducted in microcosms or ponds under field condi-
tions, which also have been reviewed in Racke (
1993
). Here the mean BCF was 1,734
and geometric mean 935 (SI Table
5
). Assuming a K
OW
of 100,000 and a lipid content
of 5% suggests an equilibrium BCF of 5,000, but lower than equilibrium values can
be expected as a result of metabolic conversion and slow uptake.
Several studies on uptake of CPY from water and sediments have been reported
since 2000 (Table
11
). Results of several other recently-published studies were not
usable. Two studies of marine clams were conducted using
14-
C-CPY but results
were only reported as percentages (Kale et al.
2002
; Nhan et al.
2002
) and BCFs
could not be calculated. Uptake of CPY from water by the fish, hybrid red tilapia,
was measured by gas-chromatography (Thomas and Mansingh
2002
) but a BCF
could not be calculated. A study of uptake and depuration of
14-
C-CPY reported
BCFs for 15 species of FW aquatic invertebrates (Rubach et al.
2010
). Unfortunately,
the BCFs were based on total
14-
C in the organisms and, because the
14-
C-label was
in the di-ethyl-phosphorothiol moiety of the CPY molecule, radioactivity measured
in the organisms did not represent only CPY, but included other phosphorylated
proteins such as AChE, BuChE, and paraoxonase. Therefore, as has been pointed
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