Final answer:
Negative interactions with hair relaxers can occur when they come into contact with substances like lye, organic solvents such as alcohols, and heavy metal ions, leading to potential hair damage and skin burns.
Step-by-step explanation:
Substances that can interact negatively with the ingredients in hair relaxers include lye (sodium hydroxide or potassium hydroxide), organic solvents such as alcohols, and strong oxidizing agents. Lye, commonly found in drain cleaners, is extremely caustic and can damage the hair and scalp. Organic solvents, like alcohol which is used to sterilize skin, can denature and coagulate proteins, and therefore might adversely affect the integrity of hair treated with relaxers. Furthermore, heavy metal ions such as Pb²⁺ and Hg²⁺ can react with -SH groups, causing damage to hair proteins. It is essential to avoid mixing these substances with hair relaxers as they can lead to chemical reactions that result in hair damage or skin burns.