Superbubble Hii regions: how self-enriched should they be?

I modeled the pollution of low metallicity (Z=0.001) superbubble Hii regions with the ejecta from single stellar populations of 10⁴-10⁶M_⊙ in mass. I found that the He, C, N, and O abundance enhancements in the Hii regions, due to pollution with the enriched winds from Wolf-Rayet stars, are insignificant at 5Myr. The few localized metal enhancements observed so far in resolved extragalactic Hii regions are not associated with superbubbles and remain to be modeled in detail.