Most conventional paints and coatings contain and emit Volatile Organic Compounds (VOCs). Some types of VOCs contribute to smog, and many VOCs are emitted or “offgassed” indoors and contribute to indoor air pollution. VOCs can cause respiratory problems and some are known carcinogens.
Fortunately, almost every major paint manufacturer (and retailer) now has a low-VOC or zero-VOC product line. Most of these products are also low-odor, as some VOCs are responsible for to that noxious “new paint smell.”
I maintain an online product listing of Low-VOC and Zero-VOC Wall Paints, which I recently updated. The listing includes natural paints (e.g., plant- or mineral-based), as well as more conventional synthetic (e.g., latex/acrylic) paints.
A few paint manufacturers, such as AFM Safecoat and YOLO Colorhouse formulate their entire line of paints and primers to be low- or zero-VOC and low-toxic. While most low-VOC paints are interior paints, some brands (including those two) also offer low-VOC exterior paints.
My listing indicates which paint lines have been Green Seal certified or SCS Indoor Advantage Gold certified. GreenGuard also certifies paints; it has a basic Indoor Air Quality Certified program, as well as a more stringent Children and Schools Certified program. All of these certification programs are primarily focused on testing products’ VOC emissions.
Unfortunately, synthetic paints often contain other toxic compounds, beyond VOCs, such as phthalates (which are endocrine-disrupting chemicals), propylene glycol and glycol ethers (PGEs), certain heavy metals, and toxic biocides or fungicides. (Green Seal’s certification standard prohibits the use of some of those compounds.) See this Pharos article for additional information on paint toxicity.