Abstract |
The profile of polycyclic aromatic hydrocarbons (PAHs) in selected smoked fish species from a typical rural market in Nigeria, West Africa, was determined employing Gas Chromatographic technique, in order to evaluate potential carcinogenic risk on the unwary consuming public. The mean concentrations of the individual PAH congeners in specific fish species ranged from below quantification limit (BQL) for chrysene in Scomber scombrus and Trichurus lepturus to 8.822 µg/kg for indeno(1,2,3c-d)pyrene in Trachurus trachurus. Significant differences (p<0.05), were observed in the mean concentrations of all the PAH congeners in fish between months while no significant differences (p>0.05), were observed in the mean concentrations of pyrene, chrysene, benzo(k)fluoranthene, and benzo(a)anthracene, between fish species. The estimated daily intake (EDI) values for PAHs in mg/person/day, ranged from 0.00005 for benzo(k)fluoranthene to 0.278 for indeno(1,2,3c-d)pyrene while the hazard quotient (HQ) values ranged from 0.004 for benzo(k)fluoranthene in the fish species to 17.64 for indeno(1,2,3c-d)pyrene in T. lepturus . The toxic equivalency (TEQ) values were generally dominated by benzo(a)pyrene, which peaked at 6.206 in T. lepturus. The cancer risk factors revealed that indeno(1,2,3,c-d)pyrene, benzo(b)fluoranthene, benzo(a)pyrene and benzo(a)anthracene presented critical values as they exceeded the United States Environmental Protection Agency (USEPA) cancer risk guideline value of 1.0 x 10-6. It was advocated that such fish should be consumed with caution in order to avert unwholesome carcinogenic health effects in the long run.
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Abstract |
In this paper, chance constrained programming (CCP) problems with some dependent exponential distributed random parameters are considered. Firstly, a suggested bivariate exponential distribution model is presented. This model is an important for financial, insurance, economical problems, etc.
Secondly, a proposed method to convert (CCP) problems to the equivalent deterministic programming problems in two cases: (i) for individual constraints and some L.H.S. parameters a ̃ij follow a suggested model, (ii) for the joint (dividual) constraints and some R.H.S. random parameters b ̃i follow a suggested model also.
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