Indoor Air pollution Flashcards
How does formaldehyde concentrations compare indoors to outdoors?
10ppb in urban areas, exceeding 1,000 ppb indoors sometimes, on average 5-20 in American homes.
What are its sources?
Foam insulation and adhesive in manufacturing plywood/particleboard, in dyes and in resins.
How is it emitted?
FAH emits following manufacture, and increases with temperature and relative humidity, and declining with age.
Why does FAH emit?
Reactiosn of water vapor in humid air with methylene bridges joining amide groyups within polymer backbone of FAH.
What are common symptoms of ‘sick building syndrome?
Headaches, eye irritation, dizziness/nausea, and dry/itchy sking.
How dies FAH relate to cancer?
Considered a possible human carcinogenic, with carcinogenic effects on animals in the respiratory system especially.
What is Benzene?
A stable, volatile liquid hydrocarbon being a constituent of gasoline, used as a solvent in many organic products like paints and inks.
How does it relate to cancer?
Known human carcinogen, increasing rate of leukemia
How was it regulated?
Replaced by toluene: this includes a methyl group providing attachment site for liver enzymes to break down the molecule.
Where are Nitrogen Dioxide concentrations highest?
Where stoves, space heaters, and water heaters are used.
How is it formed?
Where thermal temepratures are high where nitrogen and oxygen combine to form NO which oxidises to NO2.
What is an example of its health impacts?
15-ppb increase in mean NO2 cocnentration in homes increase lower respiratory system symptoms in children by 40%.
What is Carbon Monoxide?
A colorless, odorless gas, with concentratiosn increasing with incomplete combustion of carbon containing fuels like wood, gasoline, kerosene or gas.
How does it exert health effects?
Inhalation and its capacity to bind hemoglobin, increasing heart disease mortality even if several percent of hemoglobin is tied up as CO complex.
