Correlation between the association and the desmutagenicity of benzo(a)pyrene by hemin: comparison with hemoproteins, transient metals and amines

The mutagenicity of the potent carcinogen benzo(a)pyrene proved to be lost by binding with hemin and other tested compounds. The association constant (Kass) and the desmutation constant (Kmut) of benzo(a)pyrene and hemin were 8.5 x 10(4) M(-1) and 7.0 x 10(-4) M(-1), respectively. The correlation coefficient (gamma) of the association and the desmutation of benzo(a)pyrene and hemin was nearly 1, and the coefficient of regression of association on the desmutation, gamma (sigma ass/sigma mut), was 0.78. The correlation of other compounds, ferric chloride among transient metals, and 3,3'-diaminodipropylamine and p-phenylenediamine, were also almost 1 in both values, but their Kass an Kmut were must smaller than those of hemin: Kass:Kmut, 525 M(-1):520 M(-1) for ferric chloride, 2.2 x 10(3) M(-1):2.3 x 10(3) M(-1) for diaminodipropylamine and 175 M(-1):125 M(-1) for p-phenylenediamine. Good agreement of Kass and Kmut means that the desmutation of benzo(a)pyrene is caused by binding with tested materials.