IR-renormalon contribution to the polarized structure function g1

An estimation of the higher twist contribution to the polarized nonsinglet structure function g1 is given. Its first moment is generally assumed to be small but this could be due to a cancellation of its contribution in different Bjorken-x ranges. We estimate the magnitude of g1tw4 as a function of x in the framework of the renormalon method. The calculated higher-twist-correcti to g1 turn out to be in fact small for all x values. The correction to the determination of the nonsinglet matrix element dNS(2) from data for transversely nucleon polarization due to the calculated higher twist effects is of order 10%.