diff --git a/tox.ini b/tox.ini
index 94a1961b9..ed733aa5c 100644
--- a/tox.ini
+++ b/tox.ini
@@ -10,8 +10,8 @@ setenv =
     PYTHONPATH = {toxinidir}
     COV_CORE_SOURCE =
 passenv =
-    CI,
-    GITHUB_*,
+    CI
+    GITHUB_*
     LD_LIBRARY_PATH
 download = True
 install_command =