UVinduced

UV-induced refers to effects that are produced by ultraviolet radiation. Ultraviolet radiation spans roughly 10 to 400 nanometers and is commonly divided into UVA (315–400 nm), UVB (280–315 nm), and UVC (100–280 nm). UVC is largely absorbed by Earth's atmosphere and does not reach the surface; UVA and UVB are the primary sources of UV-induced effects in biology, health, and materials on Earth.

In biology, UV-induced DNA damage is most notable. UVB, and to a lesser extent UVA, can induce covalent bonding between adjacent pyrimidine bases, forming cyclobutane pyrimidine dimers and 6-4 photoproducts. These lesions distort the DNA helix and can lead to mutations if not repaired. Nucleotide excision repair removes such lesions. UV exposure also generates reactive oxygen species that damage proteins, lipids, and nucleic acids, contributing to cellular stress.

Cells respond by activating damage signaling pathways, such as p53, which can cause cell-cycle arrest or apoptosis when DNA damage is irreparable. Organisms may increase production of protective compounds—melanin in humans and UV-absorbing pigments in plants—in response to UV exposure.

In materials science and chemistry, UV-induced processes include polymerization and curing using photoinitiators, as well as photodegradation of polymers and dyes. Protective measures such as UV absorbers, stabilizers, and coatings help mitigate unwanted UV-induced damage in plastics, paints, and textiles.

Because UV-induced effects span biology, medicine, ecology, and materials engineering, the term is widely used to describe reactions, damage, and responses initiated by ultraviolet radiation.