pubhtlh 264 - week 2: indoor pollution

why indoor pollution is important to address?

• indoor - 89%

• transit - 6%

• outdoors - 5%

8 indoor chemical agents

• radon

• smoking, vaping, environmental tobacco smoke

• formaldehyde

• asbestos

• lead

• organic chemicals

• pesticides

• combustion products

6 indoor biological agents

• mold

• pollens

• viruses

• bacteria

• household pets

• agents related to cockroaches, rodents, pests, or insects

indoor physical agents

• heat

• moisture

• light

radon (chemical agent), source & health effects

• colorless, tasteless, orderless gas (ppl don’t know they are exposed to it b/c of that

• sources: permeable soils, well water supply, natural gas, building materials, & rocks

• health effects: 2nd leading cause of lung cancer

radon history

• in 1994 national cancer institute concluded about 39% miners had lung cancer among smokers & 73% miners had long cancer among non-smokers

• in residential settings 10%-12% of lung cancer in smokers & 28%-31% in never smokers

radon vs radon daughters

• when radon decays, its radioactive products, or “radon daughters,” attach to tiny dust particles in the air.

• when inhaled, it’s lodged in the lungs, damaging tissue & causing lung cancer

• radon has a 4 half life & radon daughters have a 30 min half life (shorter half life is more dangerous b/c it is more active)

where in the u.s. is high risk of radon

northern part

smoking (chemical agent) health effects

• adults: lung cancer

• fetus/infants: prenatal complications, low birth weight, infant mortality, pnemonia, sudden infant death syndrome (SIDS), & respiratory problems

vaping (chemical agent) & health effects

• e-cigarettes make aerosol (liquid particles in gas like air), not vapor

• health effects: VOC, nicotine, ultrafine particles, cancer-causing chemicals, heavy metals (lead, nickel, and tin), flavoring like diacetyl (a chemical link to lung disease)

formaldehyde (chemical agent), source, & health effects

• colorless gas w/ strong odor

• source: compressed wood, building materials (especially for new building from engineer work), smoking, & household products

• health effects: asthma attack, nasal cancer, lung cancer, watery eyes, burning in throat, & nausea

polybromiated diphenyl ethers (PPBDE) (chemical agent) & health effects

• used as fire retardant so furniture & electronics don’t catch on fire

• health effects: thyroid hormone disruption, permanent learning/memory impairment, behavioral changes, hearing deficits, delayed puberty, decreased sperm count, fetal malformations, & possibly cancer

asbestos (chemical agent), exposure, & health effects

• mineral fiber, heat resistant; commonly used 1940-1980s for insulation as a fire retardant; symptoms don’t show up until years later

• exposure: fibers become airborne & are inhaled if asbestos-containing material is damaged; most commonly found in older homes & schools

• health effects: fibers too small to be seem w/ naked eye, but can accumulate in the lungs after inhalation; chronic toxicity is high; asbestosis (lung cancer), mesothelioma, tumors

lead and abestos (chemical agents)

• commonly used in home building until the late 1970s

• deterioration of lead or asbestos-containing materials increases risk

  • renovation/removal = increased hazard

  • cover or seal

  • professional removal

organic solvent + pesticides (chemical agent) & health effects

• organic substance that dissolves another substance, resulting in a solution

  • lipophilic and volatile liquid at room temperature

  • most commonly used for cleaning, degreasing

• pesticides (insect, termite, or rodent products)

• health effects of volatile lip-soluble organic chemicals: cause depression of cns; pesticides are neurotoxins, carcinogens, & endocrine disruptors

rachel carson - a voice for nature

• in 1962, silent spring alerted the public to the dangers of indiscriminate pesticide use

• selective use of pesticides

• led to EPA banning DDT in 1972

strategies to improve indoor air quality for chemical agents

• increased ventilation

  • move activies outdoors if possible

  • air should not be recirculated

  • air quality vs energy efficiency

• pollutant source control

• use of air cleaners (NOT air fresheners) & air disinfeciton

• reduction

  • minimize # of people within the same indoor environment in an epidemic

  • reduce duration of crowded indoor activities

biological agent sources & health effects

source: central air unites if moist can become a breeding ground and can then distribute these contaminants

health effect: allergies, infectious illnesses, toxic

sick building syndrome

when people get headaches, dizziness, and eye, nose, or throat irritation that improve after they leave the building

strategies to reduce biological agents

maintain 30-50% humidity level & good homekeeping practices

top reason indoor air quality problems in office buildings

• inadequate ventilation

• inside contamination

• unknown causes