A very significant correlation between carcinogenic activity of polycyclic hydrocarbons and certain properties of their transition states in the range of the lowest triplet states of the DNA.

A very significant correlation between carcinogenic power of polycyclic aromatic hydrocarbons and their probability of photoinduced double resonance transitions in the UV-range of about 3 to 3.5 eV is shown. The resonance can be interpreted in terms of the lowest triplet state energy of thymine at 3.25 eV and the energy difference between the triplet states of A--T and G--C base pairs. The correlation has been predicted from a hypothesis which describes cell communication by photon interaction within a cell population.