INTRODUCTION This study was initiated to determined the synergistic effects of five common air pollutants in albino rats (Rattus norvegicus) exposed continuously@ 24 hours per day@ seven days a week@ for a period of 52 weeks. The pollutants examined@ singly and in binary combination@ were three gases@ nitrogen dioxide@ sulfur dioxide@ and carbon monoxide and two particulates@ calcium sulfate and lead chlorobromide. The nominal exposure levels selected and the current Threshold Limit Values (TLV) (1) presently set for each pollutant are presented in Table 1. The nominal particle size selected for the two particulates@ calcium sulfate and lead chlorobromide@ was less than two microns (lt;2p). This report presents the results of measurements made on rats exposed singly and in binary combinations to the pollutants noted above and briefly summarizes the methodology used. A series of technical reports have been issued describing the methodology in detail; these are listed in Table 2.
API 4145-1972 history
1972API 4145-1972 CHRONIC EXPOSURE OF ALBINO RATS TO CERTAIN AIRBORNE POLLUTANTS