Aroclor 1242 inhalation and ingestion by Sprague-Dawley rats

PCBs have been considered to be almost nonvolatile and insoluble in water. However, recent studies have shown the importance of their slight solubilit y in water and capability to enter the atmosphere and disperse throughout t he global environment. This preliminary study was designed to measure uptak e and observe any physiological changes in Sprague-Dawley rats. The PCB pro duct Aroclor 1242 is the major pollutant of the Hudson River, NY, and New B edford Harbor, MA. The rats were exposed for 30 d to 0.9 mu g/m(3) via inha lation and 0.436 mu g/g (ppm) in the food. The inhalation of PCBs gave a gr eater PCB uptake than ingestion. Both routes of administration caused signi ficant serum thyroid hormone elevations. Histopathologic changes were obser ved in the urinary bladder, thymus, and the thyroid after both exposure reg iments. Rearing and ambulation were significantly decreased in both exposur e regiments in an open field behavior test.