Experimental limit on the blue shift of the frequency of light implied by a q-nonlinearity

We discuss the implications of an experiment in which the frequencies of two laser beams are compared for different intensities in order to search for a dependence of the frequency of light on its intensity. Since no such dependence was found it is possible to place bounds on a description of the electromagnetic field in terms of q-oscillators. We conclude that the value of the nonlinearity parameter is smaller than $10^{-17}~$.