Modified Buehler

Modified Buehler. Buehler (1964) developed the first test system to use an occlusive patch to maximize dermal exposure and to increase the test sensitivity (Buehler, 1964). Although, this assay is still insensitive for some xenobiotics that may not sufficiently traverse the epidermis, it is particularly useful for compounds that are either highly irritating by intradermal injection or cannot be dissolved or suspended in a form that is conducive to injection. Other advantages are that the test produces few false positives, rarely overpredicts the potency of sensitizers, and is less likely to produce limiting system toxicity or ulceration at the induction sites. Figure 15.4 shows the test design in its current (OECD) form. 

FIGURE 15.4. Line chart for modified Buehler test for delayed contact dermal sensitization in the guinea pig. 

Guinea pig OECD 406 (modified Buehler test) Nonsensitizing... 

Ecoflex (powder) was tested for its sensitizing effect on the skin of the guinea pig in the modified Buehler test according to OECD guideline 406. Skin-sensitizing effects were not observed in these animal studies. 

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