Appendix D Food Codes for NHANES - OEHHA

SRP Review Draft Version 2 June, 2012
intake via contaminated food, which in some studies summarized below was shown to
be an important route of exposure for inorganic metals. Also, many of the laboratory
BCF studies likely did not attain steady-state concentrations because exposures were
too short.
In almost all instances, acidic water bodies (generally with a pH of 6.5 or lower) will
increase accumulation of the cationic metals and oxy-anionic chromium in fish organs
and tissues compared to pH neutral (7.0 to 7.5) water bodies. The default BAFs in this
document are primarily based on pH neutral lentic water bodies, as these are the most
common in California. Consequently, the default BAFs may underestimate the actual
accumulation of a metal in fish if the water body is acidic.
I.2 Derivation of Fish BAFs
I.2.1 Semi- or Non-Volatile Organic Chemicals
I.2.1.1 Diethylhexylphthalate (DEHP)
DEHP has been detected in marine and lake sediments, as well as in marine and
freshwater sport fish (Stalling et al., 1973; McFall et al., 1985; Camanzo et al., 1987;
Mackintosh et al., 2004). However, the source of the DEHP found in these marine and
lake sediments is not likely to be solely from air emissions. The very high Kow of 7.73
and model calculations suggest that DEHP could readily bioaccumulate in fish and that
dietary uptake would be an important route of exposure (Staples et al., 1997; Gobas et
al., 2003). However, bioaccumulation and biomagnification studies of DEHP in fish
show roughly three orders of magnitude lower BCFs/BAFs than predicted based on the
Kow of DEHP. This finding is a result of trophic dilution and lack of biomagnification
through the aquatic food web, primarily due to the metabolic transformation of DEHP in
fish (Staples et al., 1997; Mackintosh et al., 2004). The term trophic dilution means that
the BAF tends to decrease as the trophic level increases.
The only freshwater study from which a field-measured BAF was developed was based
on a Dutch study investigating the occurrence of DEHP in the freshwater and fish
throughout the Netherlands (Peijnenburg and Struijs, 2006). Twenty-five samples of
bream and roach fish and 66 freshwater samples from 23 sites were collected
throughout the country. Based on the geometric mean DEHP concentration of 1.8
µg/kg wet fish and the dissolved freshwater DEHP concentration of 0.33 µg/L, a BAF of
5.5 is calculated (Table I.3). We corrected for the lipid fraction in the whole fish samples
(median: 0.5% lipid), generating a lipid-normalized DEHP BAF of 1.1 x 10 3 . Finally, we
also corrected for the muscle lipid content of rainbow trout (4%), which is approximately
eight times greater than that of the bream and roach fish, generating a BAF of 44.
An assumption used for this BAF is that the influence of collecting fish and water
samples at different times and from different locations on this BCF is not large. Another
factor to consider is that the fish in the Dutch study were collected from both lentic and
lotic water bodies. Lentic environments are characterized by still (not flowing) water, as
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