Working on the knowledge that toxicity is dose dependent, and given current exposure guidelines and regulations, turpentine would be about 4 to 5 times more toxic than standard "mineral spirits". The American Conference of Governmental Industrial Hygienists (ACGIH) is recommending a decrease in current exposure values to only 20ppm averaged over an 8-hour work day. That ain't very much.
Both materials are organic in nature, and affect the body as a central nervous system, liver, and kidney toxicant; however it takes less turpentine to create a dose-response effect than an equal amount of "mineral spirits". In addition, some of the available literature suggests exposure to turpentine has the ability to cause an allergic reaction. Just like other allergens, once allergic--always allergic. Furthermore, turpentine is flammable (flash point = 95 degrees F) as opposed to mineral spirits, which is combustible (flash point > 100 degrees F).
If you want to spray turpentine:
1. Don't. Find a suitable alternative--like mineral spirtis paint thinner.
2. If you still want to spray it, do it only in a well ventilated area: Outside, or if indoors then a PROPERLY constructed and functioning spray booth. If a spray booth is unavailable, see #1 above. In lieu of that, open some windows, get some fans going, and wear at least a 1/2 mask respirator equipped with organic vapor cartridges
3. Because of its allergic potential, consideration should be given to wearing nitrile rubber gloves (Latex is inappropriate--turpentine will degrade the rubber and diffuse through too quickly to offer adequate skin protection. In addition, potential latex allergies must also be considered.)
Hope this helps.
Gip Winecoff