Dangers of Electromagnetic Waves (Cambridge International IGCSE Science)

Dangers of electromagnetic waves

• Excessive exposure to electromagnetic radiation has harmful effects on people

  • As the frequency of the electromagnetic (EM) waves increases, so does their energy

• Beyond the visible part of the spectrum (ultraviolet waves, X-rays and gamma rays), the energy is large enough to ionise atoms

  • The higher the frequency, the more ionising the radiation

• The effects of Ionisation also depend on the type of radiation and the size of the dose

Harmful effects of EM radiation

Harmful effects of excessive ultraviolet exposure

• Ultraviolet is similar to visible light, except it is invisible to the human eye and carries a much higher energy

• If eyes are exposed to high levels of UV it can cause severe eye damage

  • Good quality sunglasses will absorb ultraviolet, preventing it from entering the eyes

• Ultraviolet can kill cells or cause them to malfunction

  • This can cause premature ageing, and diseases such as skin cancer
  • Sunscreen absorbs ultraviolet light, preventing it from damaging the skin

Harmful effects of excessive X-ray and gamma-ray exposure

• X-rays and gamma rays are the most ionising types of EM waves

  • They can penetrate the body and cause internal damage
  • They can cause the mutation of DNA, causing cancer