Non-Ionizing Radiation

non-ionizing radiation

has enough energy to move atoms in a molecule around and cause them to vibrate, but not enough the remove electrons

hertz

cycles per second

extremely low frequency (ELF)

• ranges from 50 to 60 Hz

• includes power poles, wiring

• health impacts include cardiovascular, behavioral, hormonal, and immune system changes

• childhood cancer and increase risk of leukemia in New Zealand near power lines

• adult cancer linked to occupations

• considered possibly carcinogenic

• 60% higher risk of breast cancer

Radio Frequency (RF) Radiation

• ranges from 0.5 MHz to 300,000 MHz

• higher amounts of energy compared to ELF

• found in radio antenna, cellphones, microwaves

• possibly carcinogenic

RFR and Cell Phones

• phones produce 900 to 1800 MHz

• brain is the main target

• animal study on rats showed that 2G and 3G phones caused cancer

• clear evidence of heart tumors for male rats, some evidence for brain and adrenal tumors for male rats

• use linked to thyroid cancer, exposure affects genes related to DNA repair

• parotid gland is exposed to electromagnetic radiation while using cell phone

microwave radiation

• gained popularity after WWII since it can track aircrafts

• ranges between 1 GHz to 1000 GHz

• wavelengths between 30 cm and 0.03 cm

• causes cataracts and clouding in eye lenses

• food cooked in microwaves is safe, doors designed to limit exposure & leakage; better job preserving nutrients

Habana Syndrome

• around 200 diplomats and CIA officers ill

• symptoms included headaches, hearing and vision loss, loss of motor control, and cognitive impairment

• triggered by exposure to high levels of microwave radiation

ultraviolet radiation (UVR)

• a form of non-ionizing radiation in optical range

• rays come from the Sun

• three levels: UVA, UVB, and UVC - they are sorted by wavelength

• sources include welders, arcs, tanning beds, etc.

• lower geographic latitudes have higher UVR

• affects include acute temporary blinding, retinal damage, and cancer

UVA

longest waves, 315 to 400 nm

UVB

medium waves, 280 to 315 nm

UVC

shortest waves, 100 to 289 nm (they don’t reach the Earth)

UVR Health Effects

• UVA and UVB travel through the epidermis and are absorbed by melanocytes producing melanin at epidermal-dermal junction

• UV cross linked thymine-thymine, and cytosine bases altering DNA structure

• inhibits DNA polymerase, thus arresting cell replication

• unrepaired structures become mutagenic

• if p35, a tumor suppressor gene, is unrepaired, epidermal cells hyper-proliferate

Vitamin D

• important role in Ca absorption and bone health

• synthesized in skin via exposure to sunlight

• most people get enough naturally, but at-risk groups (elderly, housebound) must take supplements

• daily intake should be between 400 and 800 IU

• lack of sun exposure is widely accepted as the primary cause of epidemic low levels

• low levels contribute to osteoporosis, osteomalacia/rickets & can play a role in cancers, multiple sclerosis, infection, hypertension, and diabetes mellitus

Hawaiian Vitamin D Study

found that individuals with abundant sun exposure do not necessarily have adequate vitamin D status

sunbathing/tanning

• can lead to skin cancer

• many people may not be aware that they are harming their cells

• most harmful UVR are UVB because they are more effective in producing short-term and long-term adverse health effects

acute effects of overexposure to UV

reddening of skin, inflammation, tanning, sunburns, phototoxicity

chronic effects of overexposure to UV

swelling, blistering, peeling, thickening of skin, photosensitivity, second degree burns, cancer

photoaging

wrinkles, spots, discoloring, leathery lesions

types of skin cancer

squamous cell, basal cell, malignant melanoma