Vaisesika Sūtras
Vaisesika Sūtra 7.1.02
pṛthivyādi-rūpa-rasa-gandha-sparśā dravya-anityatvāt-anityāś-ca ॥2॥
Form, taste, smell, and touch in earth and others are impermanent due to the impermanence of the substance.