diff --git a/tox.ini b/tox.ini
index abe3778d4ff..5ab4507b643 100644
--- a/tox.ini
+++ b/tox.ini
@@ -11,7 +11,7 @@ setenv =
     LANG=en_US.UTF-8
     LC_ALL=en_US.UTF-8
     DJANGO_SETTINGS_SKIP_LOCAL=True
-passenv = CI TRAVIS TRAVIS_* HOME
+passenv = CI,TRAVIS,TRAVIS_*,HOME
 deps =
   -r requirements/testing.txt
   debug: -r requirements/debug.txt