Skin Exposures & Effects

The skin permeation coefficient (k_p) is a measure of the conductance of skin to a particular chemical from a particular vehicle. This calculator estimates the value of k_p from an aqueous vehicle using three different models: Frasch, Potts & Guy and Modified Robinson.

Two inputs are required: molecular weight (MW) and the base-10 logarithm of the octanol-water partition coefficient (logK_ow) of the compound of interest. These models have been optimized based on experimental data compiled by Flynn.

The user may also browse the Flynn data base of experimental k_p's. Calculation of the modeled k_p will automatically be performed for the chosen chemical.

Syracuse Research Corporation’s interactive logK_ow
(External Link: http://www.syrres.com/esc/est_kowdemo.htm)
You will need the CAS number or SMILES notation for the compound of interest.

Requires Java installed. Download Java Free

For additional information contact Fred Frasch at HFrasch@cdc.gov or Adam Fedorowicz at AFedorowicz@cdc.gov.

REFERENCES

• Frasch Model
  Frasch, H. F. (2002) A random walk model of skin permeation. Risk Anal. 22, 265-276
• Potts and Guy Model
  Potts, R. O., and Guy, R. H. (1992) Predicting skin permeability. Pharm. Res. 9, 663-669
• Modified Robinson Model
  Wilschut, A., ten Berge, W. F., Robinson, P. J., McKone, T. E. (1995) Estimating skin permeation. The Validation of five mathematical skin permeation models. Chemosphere 30, 1275-1296
• Flynn Data Base Flynn, G. L. (1990) Physicochemical determinants of skin absorption. IN: Garrity, TR, Henry, CJ (Eds) Principles of route-to route extrapolation for risk assessment. Elsevier, New York, pp 93-127.

Ongoing Skin Research