The phrase "use of harmful chemicals" refers to the application or employment of chemical substances that have the potential to cause damage, injury or harm to people, animals, plants or the environment. These chemicals may be toxic, corrosive, carcinogenic or otherwise hazardous and can result in a wide range of negative consequences if not handled, stored or disposed of properly. The term is often used in relation to industries such as manufacturing, agriculture, construction, and waste management where the use of chemicals may be unavoidable but must be carefully regulated and controlled to minimize risk.