Final answer:
An act or law may require a P.D. (Patch Test) prior to the application of aniline derivative tints, which helps to ensure consumer safety and minimize the risk of adverse effects.
Step-by-step explanation:
The act or law mentioned in the question is not specified, so we cannot provide a specific answer. However, based on the information provided, it seems that the law may be related to the regulation of aniline derivative tints. Aniline derivative tints are often used in various applications, including hair coloring. The presence of aniline derivatives in tints may pose health risks, and therefore, a pre-application P.D. (Patch Test) is often required to check for any adverse reactions or allergies.
The P.D. test involves applying a small amount of the tint or dye to a small area of the skin (usually behind the ear or on the arm) and observing for any negative reactions. This test helps to ensure the safety of individuals applying the tints and prevents potential allergic reactions. By requiring a P.D. test prior to the application of aniline derivative tints, the law aims to protect consumers and minimize the risk of adverse effects.