Appendix D Food Codes for NHANES - OEHHA

Scientific Review PanelSRP Draft Version 2 February,June 2012
Based on the estimated intake of 16 measured PAHs in simulated smoking
studies and the PAHs found in breast milk from long-time smoking mothers by
Zanieri et al. (2007), OEHHA was able to estimate transfer coefficients (Tco) with
a modified version of Equation J-1:
Tcohmi = Cmi/(Ccig_i x Icig/day x fsmoke) Eq. J-7
where:
Cmi = adjusted geometric average ith PAH concentration due to smoking
(µg per kg milk as wet weight)
Ccig_i = geometric average dose of the ith PAH per cigarette (µg/cigarette
averaged across experiments)
Icig/day = geometric average number of cigarettes smoked (4.75
cigarettes/day)
fsmoke = adjustment for under-reporting of smoking frequency (2)
Cmi is the adjusted geometric average of the ith PAH in whole milk due to
smoking. OEHHA obtained these estimates by converting arithmetic estimates to
geometric estimates of the mean and standard deviation and subtracting the GM
concentration in the milk of primarily urban nonsmokers from the GM
concentration in the milk of urban smokers. This adjustment accounts for oral
intake of PAHs from dietary sources and inhalation of PAHs in urban air from
combustion sources other than cigarettes. Implicit in this adjustment is the
assumption by OEHHA that oral intake and exposure to other airborne PAHs is
similar between smokers and nonsmokers who participated in the Zanieri study.
OEHHA also included a 2-fold smoking habit adjustment-factor (fsmoke) in Eq. J-7
based on published data to account for the recognized tendency of smokers to
under-report their smoking habits. The studies examined the accuracy of selfreported
smoking habits among pregnant women and parents with small children
(Marbury et al., 1993; Graham and Owen, 2003). They measured airborne
nicotine in the smoker’s breathing zone and obtained the number of cigarettes
smoked per day by each smoker. The data presented in Figure (1) of Marbury et
al suggest that mothers under-reported their smoking rate by 50% (Marbury et
al., 1993).
Table J.3-4 presents the Tcos for cancer and noncancer PAHs calculated using
Eq. J-7. However, Zanieri and Del Bubba did not find measurable levels of some
PAHs, particularly PAHs with 5 or 6 carbon rings, in milk from nonsmokers. In
these cases, the concentration representing half the limit of detection (between
0.006-0.014 µg/kg) was used as the background concentration of the PAH in
mother’s milk.
There are two main limitations in the data provided in Table J.3-4. For some
PAHs, no individual Tco was calculated because the concentration of the
J-24