Appendix D Food Codes for NHANES - OEHHA

Scientific Review PanelSRP Draft Version 2 February,June 2012
found an additional 50% reduction (1.75 µg/dL) in the U.S. adult population
(CDC, 2005).
As of the date of this report, measured levels of lead at ambient air quality
monitoring sites in California are very low. Lead exposure in the California
population is likely to occur from sources other than Hot Spots facility emissions,
such as old lead-based paint. However, no threshold has been identified for leadinduced
neurotoxicity in children and therefore an evaluation of all potential
routes of exposure for Hot Spots facilities is prudent. Further, there are significant
lead emissions from some Hot Spots facilities.
In an effort to derive lactation transfer coefficients for inorganic lead, OEHHA
drew from studies conducted on subjects exposed to lead through multiple
pathways at higher levels from other areas of the world. OEHHA assumes that
the transfer of lead derived from these studies serves as a reasonable surrogate
for the transfer of lead from contaminated media near a Hot Spots facility in
California.
J.4.1 Inorganic Lead in Human Milk
Breast milk levels of lead correlate with levels of lead in whole blood but are
generally much lower (Sternowsky and Wessolowski, 1985; Castellino and
Castellino, 1995; Li et al., 2000; Ettinger et al., 2004). Castellino et al (1995)
reviewed 11 studies conducted between 1933 to 1989 and observed that in the
vast majority of cases, the mean values of lead in breast milk vary from 0.17 to
5.6 µg/L (Castellino and Castellino, 1995).
Ursinyova and Masamova (2005) published a table of 32 human milk summary
estimates from studies published between 1983 and 2001. Mean human milk
levels of lead generally ranged from 0.5 to 50 µg/L (Ursinyova and Masanova,
2005). Average blood lead levels during that timeframe ranged from 24 to 460
(µg/L) (Gulson et al., 1998a).
Because lead levels in milk correlate well with whole blood, OEHHA searched for
studies that reported both lead levels in milk and blood before and/or during
lactation for derivation of a lactational Tco for lead. However, several
investigators have questioned high results from early studies of lead in breast
milk. For example, Ettinger et al (2004), Gulson (1998b) and others cautioned
that high levels of lead in breast milk might be due to contamination from some
past sample collection techniques (Hu et al., 1996; Newman, 1997; Gulson et al.,
1998a; Smith et al., 1998; Ettinger et al., 2004). These sources of lead include
the use of the following products to prepare nipples or express breast milk:
• lead acetate ointment
• lead in nipple shields
• lead in alcohol wipes from foil wrap
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