  In the model of a first order quark-gluon/hadron phase transition in which
the hadronic phase is considered as vacuum bubbles growing in the quark-gluon
background with chiral symmetry broken inside the bubble, we find the estimate
for the length scale associated with inhomogeneities originated during the
transition, $10$ m $\;\stackrel{<}{\sim }\ell \stackrel{<}{\sim }40$ m, being
sufficient to produce significant effects on cosmological nucleosynthesis.
