diff --git a/backend/src/lib/userApiKeys.ts b/backend/src/lib/userApiKeys.ts
index 4355c93..cbc3153 100644
--- a/backend/src/lib/userApiKeys.ts
+++ b/backend/src/lib/userApiKeys.ts
@@ -37,12 +37,9 @@ export function hasEnvApiKey(provider: ApiKeyProvider): boolean {
 }
 
 function encryptionKey(): Buffer {
-    const secret =
-        process.env.USER_API_KEYS_ENCRYPTION_SECRET ||
-        process.env.API_KEYS_ENCRYPTION_SECRET ||
-        process.env.SUPABASE_SECRET_KEY;
+    const secret = process.env.USER_API_KEYS_ENCRYPTION_SECRET;
     if (!secret) {
-        throw new Error("API key encryption secret is not configured");
+        throw new Error("USER_API_KEYS_ENCRYPTION_SECRET is not configured");
     }
     return crypto.createHash("sha256").update(secret).digest();
 }