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 solubility in water and capability to enter the atmosphere and disperse throughout the global environment. This preliminary study was designed to measure uptake and observe any physiological changes in Sprague-Dawley rats. The PCB product Aroclor 1242 is the major pollutant of the Hudson River, NY, and New Bedford Harbor, MA. The rats were exposed for 30 d to 0.9 microg/m3 via inhalation and 0.436 microg/g (ppm) in the food. The inhalation of PCBs gave a greater PCB uptake than ingestion. Both routes of administration caused significant serum thyroid hormone elevations. Histopathologic changes were observed in the urinary bladder, thymus, and the thyroid after both exposure regiments. Rearing and ambulation were significantly decreased in both exposure regiments in an open field behavior test.