|MadSci Network: Environment & Ecology|
Dust is made of just about everything. Household dust is composed primarily of things like human skin and hair, waxes, pollen, mold, fungi, lichen, tiny particles of wood, paint, fibers from fabrics such as wool, nylon, rayon, acrylic (and in the disco '70s lots and lots of polyester), foam rubber, sheet rock, plant and vegetable matter, insect parts, and of course every form of pollution such as auto and industrial emissions, heavy hydrocarbon waste from your oil or gas heater, even tiny bits of metal debris from door hinges or any place where metal and friction meet, lots of food waste, and loads of paper fiber...
If you take a few fingers full out of your vacuum cleaner, put it in a plastic bag, and bring it to school, you can look at a glob under a microscope at various powers and see all kinds of really nasty looking things in there. You'll need to pull the blobs apart to differentiate some of the more twisted items - but it's totally hideous.
If you're wandering about it, it's nothing new. We evolved with dust, all life did. Dust is more ancient than life itself.
A point or two of interest. Lead paint makes inhalable lead dust. Asbestos products make asbestos dust. Smoke of any sort creates dust. Lead levels in humans as a result of exposure to inhalable lead dust from paint is not only measurable (from a study done in Philadelphia) but dangerously high in some cases. People with mold or fungi allergies react most in fall and spring when mold and fungi levels are high, from inhaling the dust they create.
A disease recently dubbed Multiple Chemical Sensitivity is a condition where certain people suddenly and inexplicably become allergic to just about every synthetic chemical produced by man, and have intense breathing problems as a result of the chemical dust which envelops us every day from common plastics which are found on every table, counter, desk, wall, computer, fabric, shoe, soaps, shampoos, even in ice cream...everything; and the dust from dyes which coat every thing around us, the walls, the furniture, clothing, hair, carpets, cars, roads, make-up; and pulp dust from the ultimate culprit of all, paper, which not only contains synthetics, plastics as fillers, but bonded together with urea formaldehyde which is toxic, mutagenic, hyper-allergenic, carcinogenic, and smells real nasty. Urea formaldehyde, as a binder, is emitted from paper as a vapor, and because it is a binding agent binds tiny particles and vapors together to make more dust, which in turn concentrates the urea formaldehyde into a potent pellet for inhalation. People with MCS have it rough for years until a reluctant diagnosis is made - very few doctors will, if any, hand out a diagnosis of MCS, which isn't officially recognized as a disease, but only debated as a syndrome.
I've talked way too much about dust without mentioning that comets are made primarily of dust. In space, dust is more primitive, mostly frozen bits of gaseous ice crystals, a very small percentage of metals and ores, debris from planets and large objects which have been impacted by meteorites and comets. We just missed the Leanid meteor storm, a periodic meteor shower which is actually the tail of a comet (whose name escapes me). I understand that if you were in China this Nov. 17 you could have seen what literally looked like a shower of meteors (several per second) because we passed right through the comet's tail. But the path was so narrow that by the time the Earth rotated around so that we were facing the storm, we had already passed through the path of the tail and if lucky, saw maybe 2 or 3 events per hour. What a drag.
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