Index: pym/portage/__init__.py
===================================================================
--- pym/portage/__init__.py	(revision 14850)
+++ pym/portage/__init__.py	(revision 14852)
@@ -1360,7 +1360,8 @@
 
 	_env_blacklist = [
 		"A", "AA", "CATEGORY", "DEPEND", "DESCRIPTION", "EAPI",
-		"EBUILD_PHASE", "EMERGE_FROM", "HOMEPAGE", "INHERITED", "IUSE",
+		"EBUILD_PHASE", "ED", "EMERGE_FROM", "EPREFIX", "EROOT",
+		"HOMEPAGE", "INHERITED", "IUSE",
 		"KEYWORDS", "LICENSE", "PDEPEND", "PF", "PKGUSE",
 		"PORTAGE_CONFIGROOT", "PORTAGE_IUSE",
 		"PORTAGE_NONFATAL", "PORTAGE_REPO_NAME",