Scientific Reports:

April 2006: Indoor Air Chemistry: Cleaning Agents, Ozone and Toxic Air Contaminants  (206 page PDF file)

Conclusions:
The study results indicate that, in California and elsewhere, elevated inhalation exposures to air pollutants can be expected to occur under some circumstances owing to the use of common cleaning products and air fresheners. Several of the products studied contained and emitted substantial amounts of a single TAC, 2-butoxyethanol. This ethylene-based glycol ether was found to be an active ingredient in six of the 21 products characterized. The measured peak concentrations of 2-butoxyethanol owing to the use of these products were below relevant acute
exposure guidelines. However, modeled exposures for high-use scenarios suggest that the California acute (one-hour) exposure level of 14 mg m-3 might be exceeded under some circumstances. Also of potential concern are the terpenes and related unsaturated organic compounds. These constituents are widely used as solvents and as scenting agents. Many species in this class react rapidly with ozone, leading to the formation of formaldehyde, a TAC with a low chronic reference exposure level, and particulate matter, a regulated pollutant class in ambient air. Other oxidation products are also formed with unknown toxicological properties (e.g., hydroperoxides from linalool.) Thus, it appears that, when compared with health-based concentration guidelines and standards, the levels of 2-butoxyethanol, formaldehyde and particulate matter associated with the use of certain consumer products can be high enough under some circumstances to warrant further consideration. Further consideration should also be given to the toxicological properties of yet-to-be-evaluated oxidation byproducts of ozone-terpene
chemistry.