diff --git a/sentry.conf.py b/sentry.conf.py
index f52638c..0a0fde1 100644
--- a/sentry.conf.py
+++ b/sentry.conf.py
@@ -49,6 +49,7 @@
 #  BITBUCKET_CONSUMER_KEY
 #  BITBUCKET_CONSUMER_SECRET
 from sentry.conf.server import *  # NOQA
+from sentry.utils.types import Bool, Int
 
 import os
 import os.path
@@ -276,12 +277,13 @@ SENTRY_WEB_OPTIONS = {
 ENV_CONFIG_MAPPING = {
     'SENTRY_EMAIL_PASSWORD': 'mail.password',
     'SENTRY_EMAIL_USER': 'mail.username',
-    'SENTRY_EMAIL_PORT': ('mail.port', int),
-    'SENTRY_EMAIL_USE_TLS': ('mail.use-tls', bool),
+    'SENTRY_EMAIL_PORT': ('mail.port', Int),
+    'SENTRY_EMAIL_USE_TLS': ('mail.use-tls', Bool),
     'SENTRY_EMAIL_HOST': 'mail.host',
     'SENTRY_SERVER_EMAIL': 'mail.from',
     'SENTRY_ENABLE_EMAIL_REPLIES': 'mail.enable-replies',
     'SENTRY_SMTP_HOSTNAME': 'mail.reply-hostname',
+    'SENTRY_SECRET_KEY': 'system.secret-key',
 
     # If you're using mailgun for inbound mail, set your API key and configure a
     # route to forward to /api/hooks/mailgun/inbound/
@@ -299,8 +301,6 @@ ENV_CONFIG_MAPPING = {
 
     'VSTS_CLIENT_ID': 'vsts.client-id',
     'VSTS_CLIENT_SECRET': 'vsts.client-secret',
-
-    'SECRET_KEY': 'system.secret-key',
 }
 
 
@@ -309,14 +309,13 @@ def bind_env_config(config=SENTRY_OPTIONS, mapping=ENV_CONFIG_MAPPING):
     Automatically bind SENTRY_OPTIONS from a set of environment variables.
     """
     for env_var, item in six.iteritems(mapping):
-        value = env(env_var)
-        if value is None:
+        try:
+            value = os.environ[env_var]
+        except KeyError:
             continue
         if isinstance(item, tuple):
             opt_key, type_ = item
-            # only coerce the value if its not falsey (e.g. '')
-            if value:
-                value = type_(value)
+            value = type_(value)
         else:
             opt_key = item
         config[opt_key] = value