Rb. Schlesinger, INTERACTION OF GASEOUS AND PARTICULATE POLLUTANTS IN THE RESPIRATORY-TRACT - MECHANISMS AND MODULATORS, Toxicology, 105(2-3), 1995, pp. 315-325
Human contact with air pollution usually involves exposure to more tha
n one chemical, and biological responses to the inhalation of polluted
atmospheres likely depend upon the interplay between individual mater
ials. Thus, characterizing effects from exposures to mixtures of air p
ollutants is necessary for adequate quantitation of health risks. Expo
sure to gas/particle mixtures may result in respiratory tract response
s which are additive, or reflect synergistic or antagonistic interacti
ons. The occurrence and type of interaction depends upon numerous fact
ors, including the biological endpoint being examined and the specific
exposure conditions, such as concentration, duration, and the physico
chemical characteristics of the exposure atmosphere. It is, therefore,
not always possible to predict solely from the presence of certain po
llutants in a complex atmosphere exactly whether there will be an inte
raction and, if so, what type it will be. This complicates attempts to
relate responses observed in laboratory studies of mixtures to those
which may occur under ambient patterns of exposure, an extrapolation n
eeded for human risk assessment.