Permeation of diethyl phthalate through hairless guinea pig skin.
Frasch-H; Barbero-A; McDougal-J
American Industrial Hygiene Conference and Exposition, May 8-13, 2004, Atlanta, Georgia. Fairfax, VA: American Industrial Hygiene Association, 2004 May; :25
Dermatomed abdominal hairless guinea pig (HGP) skin was used. From each HGP (n = 4), six skin punches were mounted on Franz-type diffusion cells. Saturated aqueous (HEPES-buffered Hanks balanced salt solution (HBSS)) solution of DEP was placed in donor compartments of three cells; pure DEP was placed in three cells. Accumulation of DEP in receptor fluid (HBSS) was measured over 5 hr. Skin sections from the same animals were equilibrated in DEP-saturated HBSS and in neat DEP. Uptake of DEP was measured. For each n, data from three replicates were averaged. The following were determined: steady-state flux (Jss); lag time (tlag); permeation coefficient (kp); skin-HBSS partition coefficient (K); DEP solubility in HBSS; neat DEP solubility in skin. Data are mean +/- SD. Jss (µg.hr-1.cm-2) was greater (P = 0.015) from saturated HBSS (31.4 +/- 11.7) than from neat DEP (9.8 +/- 3.5). tlag (hr) did not differ (0.63 +/- 0.23 vs 0.59 +/- 0.45). kp (cm.hr-1) from saturated HBSS: 3.4x10-2 +/- 9.7x10-3; from neat DEP: 8.7x10-6 +/- 3.2x10-6. K: 3.9 +/- 0.8. DEP solubility (µg/ml) in HBSS: 921 +/- 126; in skin: 8925 +/- 3339. Skin may be a significant route of uptake of DEP. Jss from saturated aqueous solution was ~3x greater than from pure chemical, even though the estimated chemical potential for neat DEP was greater than for saturated solution. Increased skin permeability caused by hydration may be the mechanism.
Skin-tests; Laboratory-testing; Skin-absorption; Skin-exposure; In-vitro-study
Research Tools and Approaches: Exposure Assessment Methods
American Industrial Hygiene Conference and Exposition, May 8-13, 2004, Atlanta, Georgia