Appendix D Food Codes for NHANES - OEHHA

Scientific Review PanelSRP Draft Version 2 February,June 2012
PeCDD (1,2,3,7,8 Penta-CDD) is always found in the emissions from waste
incinerators (USEPA, 1998). Early studies indicated that the presence of
1,2,3,7,8-PeCDD with other PCDDs/PCDFs in human milk suggested that the
major source of exposure came from waste incinerator emissions (Buser and
Rappe, 1984; Rappe et al., 1985; Mukerjee and Cleverly, 1987). Note that these
congeners are measurable in human milk currently (Sasamoto et al., 2006; Zhao
et al., 2007; Raab et al., 2008).
Levels of PCDFs in human milk tend to be lower than PCDDs. However, PCDFs
dominate in particulates emitted by combustion sources, including hazardous
waste incinerators, and are present in higher concentrations in the atmosphere
than PCDDs (USEPA, 1998). HxCDDs/HxCDFs and HpCDDs/HpCDFs are
prevalent in pentachlorophenol. Incineration of wood and other products
impregnated with pentachlorophenol results in the formation of these congeners
and emissions of hexa- and hepta-CDDs/CDFs. Both 1,2,3,7,8 and 2,3,4,7,8-
PeCDFs have been detected in human milk, but 90% of the PeCDFs is generally
2,3,4,7,8-PeCDF. 1,2,3,4,7,8- , and 1,2,3,6,7,8- HxCDFs. 2,3,4,6,7,8-HxCDFs,
and1,2,3,4,6,7,8-HpCDF are also prevalent.
Several investigators have observed that dose, degree of chlorination, degree of
lipophilicity, and molecular weight influence how much PCDD/F congener is
absorbed through the lungs or gut, metabolized and transferred from blood to
milk (Yakushiji, 1988; Abraham et al., 1998; Schecter et al., 1998; Kostyniak et
al., 1999; Oberg et al., 2002; Wittsiepe et al., 2007).
Numerous studies have attempted to correlate exposure to individual dioxins,
furans and dioxin-like PCBs from ingestion of contaminated food with levels in
human biological samples such as blood and milk. Transfer from intake sources
to human milk has often been estimated in the context of accidental or
occupational exposures or after a substantial decline in environmental
concentrations (Liem et al., 1995; Pinsky and Lorber, 1998; Liem et al., 2000;
Focant et al., 2002; Furst, 2006; Milbrath et al., 2009). Steady state conditions
are not reached in these studies because the half-lives of these compounds are
in years and exposure changed considerably over the period evaluated in each
study.
Others have attempted to model the relationship between maternal intake and
concentration in mother’s milk using an indicator compound such as TCDD
(Smith, 1987; Lorber and Phillips, 2002). Less understood is the relationship
between modeled and measured transfer estimates of individual dioxins, furans
and dioxin-like PCBs. The following sections describe the sources of data and
methods for deriving estimates of transfer for an array of dioxins, furans and
dioxin-like PCBs that have accounted to some extent for the non-steady state
condition and other confounders.
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