The acute and origin dependent loss of mature oligodendrocytes following EtOH exposure extends to multiple grey matter structures and is not an isolated phenomena within the white matter of the corpus callosum A) ROIs within the cortex (ctx, orange) and striatum (str, yellow) were selected for stereological estimation of mature OL density. (B) At P16, the densities of tdTom− mature OLs within the ctx and str were significantly diminished in EtOH-exposed animals compared to air exposed controls, (*p = 0.0385 and *p = 0.0168, respectively), (B) whereas the densities of tdTom+ mature OLs did not statistically differ between treatment groups, (ctx, p = 0.8405; str, p = 0.5967; n = 4–5 animals per group).