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Toxicology Data Network (TOXNET)

The Toxicology Data Network (TOXNET) is a series of online databases and other resources related to toxicology and environmental health.  It is part of the National Library of Medicine, and can be found on the Internet at

Vacuum Cleaners, Bag vs. Bagless

According to tests by The Good Housekeeping Institute, both bag-type and bagless vacuums do equally good jobs of keeping dust under control.  However, high filtration bags must be used in order to trap tiny particles of dust.

Vacuuming, Frequency

Ideally, an area that has heavy traffic should be vacuumed every day. But once or twice a week is more realistic with today's busy lifestyles and certainly enough for areas that aren't often used. For best results, slowly move the vacuum over the carpet several times, going back and forth and side to side in parallel rows.


Vinegar is a liquid that results from the fermentation of ethanol. The key ingredient of vinegar is acetic acid, which gives it an acidic taste. In food preparation procedures, it is a multi-purpose product as an ingredient and condiment. Outside of cooking, vinegar has medicinal, household cleaning, and agricultural applications.

There are many different types of vinegars, depending on what liquid the ethanol has been fermented in. For example, what we call white vinegar is brewed through oxidizing a distilled alcohol. Apple cider vinegar is made from apple must, which is the freshly pressed apple with its various solid components (pulp, skin, stem, etc.), and sold unfiltered. Similarly, the aromatic balsamic vinegar is made from the must of white grapes.

Because of its acidity, vinegar is a powerful cleaning agent that cuts through grease and germs while also inhibiting bacteria and mold.  


Viruses straddle the definition of life.  They contain some of the structures and exhibit some of the activities that are common to organic life, but they are missing many of the others. They consist of genetic materials (DNA or RNA) surrounded by a protective coat of protein. In order to replicate, they must inmate and take over a "host" cell.

With humans, the easiest cells to get into are those of the mucous membranes, such as those lining the respiratory passages that we breathe through because these cells are not covered by protective skin.  Because viruses are so light they can easily become airborne therefore inhaled into our respiratory systems.
Antibiotics have no effect on viruses, but antiviral drugs have been developed to treat life-threatening and more minor infections.

Volatile Organic Compounds (VOCs)

Organic chemicals all contain the element carbon (C). Organic chemicals are the basic chemicals found in living things and in products derived from living things, such as coal, petroleum, and refined petroleum products. Many of the organic chemicals we use do not occur in nature, but were synthesized by chemists in laboratories. These volatile chemicals readily produce vapors (volatize or off-gas) at room temperature and normal atmospheric pressure. Volatile organic chemicals include gasoline, industrial chemicals such as benzene, solvents such as paint thinners, lacquer thinner, degreasers, and dry cleaning fluids. Many volatile organic chemicals, such as benzene, are also hazardous air pollutants.

To "volatize"  means for a chemical to let off molecules in the form of a gas that is suspended in the air.  Another term for this process is to “off-gas.”

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