For any testing situation it is important to know exactly what the toxicologist is trying to determine so the correct in vitro test – and the correct exposure parameters - can be matched with the question.

For example, if the general area of interest is potential for eye irritation, you might find us asking the following questions (not all of which need to be answered, of course):

Is the test material a formulation or an ingredient? (Different exposure scenarios and potentially different levels of irritation might be expected from each type of material)

If a formulation:

1. How is it going to be used – is it a “leave on” material for the eye area, a “leave on” material for other areas, or a material designed to be rinsed off after use? …or is the concern about accidental exposure?
2. What do we know of it’s a) general chemistry, b) physical state, c) pH, d) solvent composition, and e) water solubility?
3. How irritating is the formulation expected to be?
4. Are we testing the formulation as “bottled” or at some further modified end use concentration?
5. Is there a benchmark material that would define the upper limit of acceptable irritation for this type of product?
6. Do you want to compare a series of formulations?
7. Is this a pre-qualification test (e.g., before clinical or use testing) or a final safety test (before marketing)?
8. Are there any client preferences (because of an historical database, for example) in assay selection?
9. Is there a specific type of information that is really needed for this formulation?

If an ingredient:

1. Is the concern the ingredient/chemical itself (e.g., pharmaceutical ingredients or intermediates) or its use in a final formulation?
2. What is know of it’s a) general chemistry, b) physical state, c) pH, d) solvent composition, e) water solubility?
3. What types of exposure to the chemical is expected?
4. How irritating is the chemical expected to be?
5. Is the material to be classified into some type of occupational safety protection category?
6. How irritating might it be and still be acceptable?
7. Are there any client preferences (because of an historical database, for example) in assay selection?
8. Is there a benchmark chemical of a similar class for comparison?
9. Is there a specific type of information that is really needed for this formulation?