diff --git a/gnu/packages/bioinformatics.scm b/gnu/packages/bioinformatics.scm
index 035a7bb808..5b9413f181 100644
--- a/gnu/packages/bioinformatics.scm
+++ b/gnu/packages/bioinformatics.scm
@@ -11970,8 +11970,8 @@ (define-public salmon
                (("lib/libdivsufsort.a") "/lib/libdivsufsort.so"))
 
              ;; Ensure that all headers can be found
-             (setenv "CPATH"
-                     (string-append (getenv "CPATH")
+             (setenv "CPLUS_INCLUDE_PATH"
+                     (string-append (or (getenv "CPLUS_INCLUDE_PATH") "")
                                     ":"
                                     (assoc-ref inputs "eigen")
                                     "/include/eigen3"))