Most people have heard about low VOC and zero VOC paints, but I would wager that most folks have no idea what VOC means. VOC is the acronym for Volatile Organic Compounds which are ingredients in paint that evaporate and cause harm to the environment by contributing to air pollution and ozone destruction.
Government regulations have forced paint companies into lowering the VOC content in their paint formulations and many have invested millions of dollars in advertising campaigns to promote their new low or zero VOC paints as being "Green" products that are "safe" for the environment. However, safe for the environment does not mean safe for human health. There are still plenty of ingredients in low VOC paints that can be very harmful to humans.
In general, lowering the VOC in paints is a good thing, just be aware that "Green" is not always completely "safe" in regards to personal health.