Volatile organic compounds or VOCs are a class of chemicals that are volatile.
Volatile organic compounds (VOCs) are organic compounds which means they contain carbon atoms. That easily become vapors or gases.

Which makes them great as a base for paints And ink. Anything that needs to dry quickly.

VOCs are released from burning fuel such as gasoline, wood, coal, or natural gas.

They are also released from many consumer products as they evaporate.

They can contain fluorine, bromine, sulfur, nitrogen and other elements.

Cigarettes
Solvents
Paints and thinners
Inks
Adhesives
Hobby and craft supplies
Dry cleaning fluids
Glues
Wood preservatives
Cleaners and disinfectants
Moth repellants
Air fresheners
Building materials and furnishings
Copy machines and printers
Pesticides

paint thinners
degreasers
aerosol cans
dry-cleaning products
paints
photographic supplies
printers and photocopying machines and supplies

Toxicity

Whenever the weather is hot, VOCs are more likely to be present in the air we breathe, and therefore more dangerous to human health. Not all VOC are known to be toxic, however in some cases there are clear negative effects, depending on the compound, the length and intensity of the exposure. Formaldehyde, diesel exhaust, styrene, benzene and perchloroethylene are known or suspected carcinogens, and heavy traffic, smoking and various types of workplace exposure can pose serious health risks. Known health effects include:
respiratory tract problems
headaches
fatigue
dizziness
nausea
liver and/or kidney damage
problems of the central nervous system
Read more here
When VOCs combine with nitrogen oxides in the air, they form smog.

Substances Toxic VOCs Listing
1,1,1-Trichloroethane
1,1,2,2-Tetrachloroethane
1,1,2-Trichloroethane
1,1-Dichloroethane
1,1-Dichloroethene
1,2,3 Trichloropropane
1,2-Dibromo-3-Chloropropane
1,2-Dibromoethane
1,2-Dichloroethane
1,2-Dichloroethene
1,2-Dichloropropane
1,3-Butadiene
2-Butanone
2-Hexanone
Acetone
Acrolein
Benzene
Bromodichloromethane
Bromoform & Dibromochloromethane
Bromomethane
Carbon Disulfide
Carbon Tetrachloride
Chlorobenzene
Chloroethane
Chloroform
Chloromethane
Dichlorobenzenes
Dichloropropenes
Ethylbenzene
Formaldehyde
Gasoline, Automotive
Hexachlorobutadiene
Hexachloroethane
Hydrazines
Methyl Mercaptan
n-Hexane
Nitrobenzene
Stoddard Solvent
Styrene
Tetrachloroethylene (PERC)
Toluene
Trichloroethylene (TCE)
Vinyl Chloride
Xylenes