Stumper #49
Question 1. 1. To what does the phrase, 'take-home exposure pathway' refer?
Answer: Materials and chemicals tracked in from the outdoors on shoes and clothing.
This "take-home" exposure pathway has been shown to be a significant contributor to residential contamination in the homes of agricultural workers, who may "wear" pesticides on their clothing and transfer the chemicals to their homes and families.
Question 2. Are dust mites insects?
Answer: No. Dust mites are Arachnids of the sub-order acari
Question 3. If we estimate that a single, tiny, dust mite takes up an area of 0.12 sq. mm, about how many do you think might fit packed closely together in a single layer on the flat, circular head of a pin that is 2 mm across: 25, 75, or 125?
Answer: about 25
Clue: Number of mites = Area of pinhead in sq. mm divided by 0.12 sq. mm
From Wikipedia:
"Dust is a general name for minute solid particles with diameters less than 500 micrometers . On Earth , dust occurs in the atmosphere from various sources; soil dust lifted up by wind ,volcanic eruptions , and pollution are some examples. Airborne dust is considered an aerosol and can have a strong local radiative forcing on the atmosphere and significant effects on climate . In addition, if enough of the minute particles are dispersed within the air in a given area (such as flour or coal dust), under certain circumstances can be an explosion hazard." (See: http://en.wikipedia.org/wiki/Dust)
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