A program which determines mutagenic concentrations of chemical carcinogens via a diffusion bioassay

A computer program implementing a mathematical model for determining mutagenic concentrations of chemical carcinogens was developed. The mathematical model describes the experiment in which a droplet of a suspected carcinogen is put at the center of a petri dish containing a bacterial lawn in an agar gel. After a period of incubation during which the chemical diffuses outward, one observes a concentric ring of mutants around the center. The largest radius at which mutation occurs, r mut, corresponds to the lowest (threshold) concentration of the chemical sufficient to produce bacterial mutation. Given a series of initial concentrations of a chemical and the resulting r mut's, the program computes and reports the threshold concentration and the decay time of the chemical. The program is also used as a method to determine the lowest mutagenic concentration for a particular time of exposure.