Appendix D Food Codes for NHANES - OEHHA

Scientific Review Panel Draft February, 2012
was absorbed, a dose of 14 C-DEHP was given intramuscularly to a group of
animals (n=5) and radioactivity was measured in urine and feces for up to seven
days.
After 24 hours, 3% (7% after correction) of the dermally applied dose was
eliminated in urine and feces. After seven days, approximately 21% (53% after
correction) of the dose had been absorbed by the skin and eliminated, while
another 11.3% of the dose had been skin stripped from the dose area. An
additional group (n=6) of animals was given DEHP (53 µg) dermally to estimate
the dose remaining in the tissues. After 7 days, 14 C content (% of applied dose)
was as follows: urine, 18 ± 4; feces, 4 ± 1; skin wash after 24 hrs, 32 ± 10; skin
patch, 13 ± 5; skin (dosed area), 5 ± 3; other tissues (liver, fat, muscle, skin), 4 ±
3%. An additional 10% was estimated to be lost to volatilization.
In the in vitro study, Ng et al. (1992) examined absorption of DEHP through
viable and non-viable dermatomed guinea pig skin (200 µm sections) with 24-hr
exposure. Radiolabeled DEHP was applied in 10 µl acetone at concentrations of
35.6, 153, or 313 nmol/cm 2 . The percentage of dose that permeated the viable
skin into the receptor fluid was 6, 2.4, and 2.5% for the low-, medium-, and highdose
groups, respectively. The percentage of dose that remained in the skin disc
was 41.0, 37.5, and 36.2% for the low-, medium-, and high-dose groups,
respectively. Use of nonviable skin resulted in a slightly decreased penetration
of 5.0% at the applied dose of 35.6 nmol/cm 2 , likely due to decreased
metabolism of DEHP. There was a dose-related increase in metabolism but the
total metabolites were between 0.5 and 1% of the applied dose for each dose
group.
Chu et al. (1996) examined the skin reservoir effects of 14 C-labelled DEHP (119-
529 µg/cm 2 ) applied on hairless guinea pigs for 24 hrs, followed by washing of
the skin to remove DEHP and analysis of DEHP distribution up to 14 days posttreatment.
As DEHP in the dosed skin decreased from 11.1% to 0.66% from 24hrs
to 7 days post-treatment, excreted DEHP gradually increased from 0.74 to
17.3%.
This finding provided evidence that DEHP stored in skin enters the systemic
circulation, although the considerable intraspecies variation for percent of
absorbed dose precluded a specific estimate of DEHP absorbed systemically
after 24 hrs post-treatment. DEHP in the carcass was 1.01 and 0.92% of applied
dose at 24 hrs and 7 days, respectively. By 14 days post-treatment, essentially
no DEHP remained in dosed skin. Autoradiographic analysis of the dosed skin at
24 hrs revealed dense radiolabel accumulation in the epidermis and along the
hair follicles, which indicated hair follicles may be a penetration pathway for
DEHP.
The authors also reported that the percent absorbed at 24 hours by Ng et al.
(1992) was higher than that found in this study, with nearly identical experimental
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