Four hundred male and female C3H/HeJ Mice were used to test the carcinogenic potential of two solid petroleum cokes@ a solid condensed emission and an aqueous condensed emission. lUce were randomly divided equally by sex into eight groups: four test material treated; two positive control (Benzo-a-pyrene); and two negative control@ a vehicle control (mineral oil) and a shaved only control. One hundred microliters (100 ??) of test materials or control materials were applied to the shaved interscapular back region of the mouse. Test materials and mineral oil were applied three times per week and Benzo-a-pyrene solutions were applied twice a week for the lifetime of test animals. Body weights and clinical observations were recorded during the study. Gross pathological and histopathological examinations were performed on all study animals. Body weight data revealed no treatment related effects for the four petroleum products or for the positive controls. Survivability of the positive control groups was significantly less than that of negative controls; test material treated groups had survivability comparable to negative controls. Only positive control groups had significantly increased tumor incidence and significantly decreased mean latency period compared with negative controls. Based on the results of histopathologic examinations@ application of 0.05% or 0.15% Benzo-a-pyrene (positive controls) induced a dose-related increase in neoplastic cutaneous lesions. There was an increased incidence of epidermal acanthosis (thickening of the epidermis) in the three test groupe which received solid coke products suspended at a 25% concentration in mineral oil and in mice which received mineral oil only. Mice which received the aqueous condensed emission had an increased incidence of hyperkeratosis compared with mice which were shaved only.
API 30-31598-1982 history
1982API 30-31598-1982 Carcinogenic Potential Petroleum Coke and Process Products