ATHEROSCLEROTIC RISKS FROM CHEMICALS - PART II - A RASH ANALYSIS OF IN-VITRO AND IN-VIVO BIOASSAY DATA TO EVALUATE 45 POTENTIALLY HAZARDOUSCOMPOUNDS

As reviewed in the Part I companion manuscript by Basavaraju and Jones (Arch Environ Contam Toxicol), atherosclerosis and carcinogenesis may share some common mechanisms of toxicological action. On that hypothe sis, standardized test data taken from the Registry of Toxic Effects o f Chemical Substances (RTECS) were used to compute relative potency fa ctors for chemical compounds associated with increased risk of atheros clerosis to humans. Potencies of the different compounds were computed relative to each of six reference compounds comprised of benzo(a)pyre ne, nicotine, cisplatin, adriamycin, estrogen, and 2,3,7,8-tetrachloro dibenzo-p-dioxin. Reference-specific potencies were all converted to a common numerical scale adjusted to unit potency for B(a)P. Because th e list of compounds contained several antibiotics, amino acids, hormon es, chemotherapeutic agents, polynuclear aromatics, alkaloids, metals, and vitamins, the standardized estimates of potency varied significan tly depending on which of the six reference compounds are considered a s standards of comparison. For the n - 1 other substances. Estimates o f relative potency, risk coefficients, and generalized risk equations are estimated for cigarette smoke condensate, dietary cholesterol, eth anol, and carbon disulfide. From data on atherosclerosis as a result o f cigarette smoking, a tentative risk was estimated as Increased Relat ive Risk = S (mg/kg-day)(-1) X dose (mg/kg-day) X RP, where the dose i s chronic intake per kilogram of body weight per day, RP is the potenc y of the compound of interest relative to that of benzo(a)pyrene, and S is 0.83, 0.25, 0.20, or 13 depending on whether cigarette smoke, cho lesterol, ethanol, or carbon disulfide epidemiological data were used as a standard of comparison.