The Fourier Amplitude Sensitivity Test (FAST) was proposed already in the 70’s, and was at the time successfully applied to two chemical reaction systems involving sets of coupled, nonlinear rate equations.
R. I. Cukier, C. M. Fortuin, Kurt E. Shuler, A. G. Petschek, and J. H. Schaibly. Study of the sensitivity of coupled reaction systems to uncertainties in rate coefficients. I theory. The Journal of Chemical Physics, 59(8):3873–3878, October 1973.
Gregory J. McRae, James W. Tilden, and John H. Seinfeld. Global sensitivity analysis - a computational implementation of the Fourier amplitude sensitivity test (FAST). Computers and Chemical Engineering, 6(1):15–25, 1982.