The Bjorken sum rules for the A = 3 and A = 1 are used as a guide to estimate nuclear effects in extractingg 1 n (x, Q 2 ) from the e 3 He data. We estimate that the combination of the spin depolarization, the nonnucleonic degrees of freedom in the A = 3 system and nuclear shadowing is likely to reduce g 1 3 H e (x ≤ 0.05) by 15% while a significant enhancement of the structure functions g 1 3 H e , g 1 3 H at x 0.1 is predicted.