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out previously (Ashauer et al.
2012
), these data were unusable. Uptake of CPY was
rapid in
Gammarus pulex
(Ashauer et al.
2012
), with equilibrium reached in less
than 1 d. Formation of an unidentified metabolite and CPYO were rapid with rate
constants of 3.5 and 0.132 d
−1
, respectively. The elimination rate constant CPYO in
G. pulex
was 0.298 d
−1
. Because the
14-
C-label was in the Et-O moieties in the mol-
ecule, a BCF for CPY could not be calculated. In a study in laboratory-based
marine microcosms, BCFs of 89-278 and 95-460 were reported in oysters and fish,
respectively (Lalah et al.
2003
), but were likely overestimated as the metabolites
were not separated from the
14-
C-CPY. Studies with usable results demonstrate that
in most cases, BCFs, BAFs, and BSAFs are small (<2,000) and not indicative of
bioaccumulation or toxicologically significant exposures to predators via the food
chain (Table
11
). The two new reports of BCFs from fish (Table
11
) were based on
very short exposures (≤3 d), and thus, cannot be compared or combined with the
studies reviewed by Racke (
1993
), which were conducted for ≥28 d. The one report
of a BMF (0.32 in the fish
Aphaniusiberus
) was based on an exposure of 32 d and
is not indicative of biomagnification (Varo et al.
2002
). One study in eleutheroem-
bryos of
Danio rerio
reported a BCF value greater than 2,000 (El-Amrani et al.
2012
), most likely because metabolic capacity in this early a stage of development
is not fully developed.
6
Assessment of Chlorpyrifos as a POP or PBT
The Stockholm convention (United Nations Environmental Programme
2001
) and
the UN-ECE POP Protocol (United Nations Economic Commission for Europe
1998
) was established to identify and manage organic chemicals that are persistent,
bioacumulative, and toxic (PBT), in that they have the potential to exceed the
threshold for toxicity, and to be transported to remote regions (persistent organic
pollutants, POPs). Classification criteria for POPs were developed from the physi-
cal, chemical, biological, and environmental properties of the so-called “dirty
dozen” (Ritter et al.
1995a
,
b
) and are based on trigger values for persistence (P)
bioaccumulation (B), toxicity (T), and propensity for long range transport (LRT)
(Table
12
). Several other initiatives to assess chemicals for properties that might
confer P, B, and T have been put in place. These are the Convention for the Protection
of the Marine Environment of the North-East Atlantic (OSPAR
1992
), the Toxic
Substances Management Policy (Environment Canada
1995
), the Toxics Release
Inventory Reporting (USEPA
1999a
), the New Chemicals Program (USEPA
1999b
),
REACH (European Community
2011
). These initiatives exclude pesticides but EC
regulation No. 1107/2009 (European Community
2009
) is specifically directed
towards pesticides and is the focus of further discussion here. EC regulation No.
1107 uses classification criteria similar to those of the POPs (Table
12
), but these
are somewhat more conservative for P and B. The criteria used to classify the PBT
character of pesticides under EC regulation No. 1107/2009 are simple (Table
12
);
the process is basically a hazard assessment that does not make full use of the rich
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