Carcinogenic polycyclic aromatic effects

Use of Response/Effect Addition in the Risk Assessment of Mixtures OF Carcinogenic Polycyclic Aromatic Hydrocarbons... 

Low concentrations of carcinogenic polycyclic aromatic hydrocarbons (PAHs) have also been evaluated for a potential hormetic effect. Exposure of grunion embryos (Leuresthes tenuis-, a freshwater tel-eost) to 7ppb of benzo [a]pyrene resulted in significantly increased respiration rates compared with unexposed controls, whereas at higher concentrations of 24.2, 361, or 868.8 ppb, respiration rates were not... 

Particles also have direct health effects when inhaled. This is especially true of very small particles that can be carried into the innermost parts (alveoli) of lungs. The particles that are most damaging are very small ones less than 2.5 pm in size (less than 1/30 the diameter of a human hair) designated PM2 5 These are mostly condensation aerosols and may contain toxic elements, such as arsenic, acids, such as H2SO4, and carcinogenic polycyclic aromatic hydrocarbons including benzo(a)-pyrene. Because of their very small size, these particles have very high surface-to-volume ratios and biochemically active surfaces. 

Hawkins, W.E., W.W. Walker, R.M. Overstreet, J.S. Lytle, and T.F. Lytle. 1990. Carcinogenic effects of some polycyclic aromatic hydrocarbons on the Japanese medaka and guppy in waterborne exposures. Sci. Total Environ. 94 155-167. 

In summary, the different joint effect models of multicomponent pollutant mixtures (i.e., the toxic unit, additive and mixture toxicity indices) were presented. Using such models to analyze the joint effect of a group of toxic and carcinogenic organic compounds such as polycyclic aromatic hydrocarbons will be presented and evaluated in Sect. 3.2. 

Factorial designs, in which n chemicals are tested at x dose levels (x treatment groups) have been suggested by the US-EPA (US-EPA 1986) as a statistical approach for risk assessment of chemical mixmres. A 2 factorial design has been used to describe interactions between the carcinogenic activity of five polycyclic aromatic hydrocarbons at two dose levels (Nesnow 1994) and a 5 design to identify nonadditive effects of three chemicals on developmental toxicity at five dose levels (Narotsky et al. 1995). 

Grimmer G et al Quantification of the carcinogenic effects of polycyclic aromatic hydrocarbons in used engine oil by topical application onto the skin of mice. Int Arch Occup Environ Health 50 95-100, 1982... 

Polycyclic aromatic hydrocarbons represent a class of compounds of great environmental concern due to their suspected mutagenic and carcinogenic properties [42-47]. Unease over the potential adverse health effects of polycyclic aromatic hydrocarbons is evident in the recent inclusion of P6 polyaromatic hydrocarbons in the Environmental Protection Agency s priority contaminates list. Polycyclic aromatic hydrocarbon contaminates pose several potential health risks due to the persistence of these compounds in the environment [48,49], their tendency to strongly bind to soil surfaces [50-52], and their presence in a wide variety of common media (air, dust, soil and food) [53]. Possible risks are associated with skin contact, inhalation or ingestion of contaminated dust, soil, or air, and ingestion of contaminated food. 

Polycyclic aromatic hydrocarbons (PAHs) are a class of persistent organic pollutants (POPs) and widespread environmental contaminants, some of which may exhibit toxic, carcinogenic and mutagenic effects Because of their low water solubility and hydrophobic nature, PAHs are partitioned... 

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