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Benzo[a]pyrene (B(a)P) is a carcinogen known to interact with DNA. In this paper we explore the possibility of using spectroscopic indicators of the interaction of B(a)P directly with dsDNA. In so doing we have examined the solvatochromism of B(a)P and modeled solvent shifts based on a purely dispersive interaction. Using this model it was possible to estimate the excited-state static polarizabilities of B(a)P as 4.9 (±0.1) × 10^-29, 4.2 (±0.1) × 10^-29, and 5.8 (±0.1) × 10^-29 m³ for the S1, S2, and S3 states, respectively. Moreover, we have used these polarizabilities to interpret the spectra of B(a)P in the presence of a 14 base-pair dsDNA oligomer in buffer solution. We provide spectral evidence that B(a)P and DNA interact, perhaps via intercalation.

High-velocity outflows, once thought to be possible only for massive pre-main-sequence stars, have been found associated with sources of less than solar mass. The possibility that even much smaller objects may, at some stage of their early lives, drive such outflows is investigated. The predicted properties of outflows from these low-mass objects are such that they would be very difficult to detect directly. If, however, the low-mass source is the companion of a larger star the outflow may have interesting and possibly detectable effects on the development of the combined system.