Co and Exhaust fumes

Co noun - A hard ferromagnetic silver-white bivalent or trivalent metallic element; a trace element in plant and animal nutrition.

Exhaust fumes and co are semantically related in colorless odorless toxic gas topic. In some cases you can use "Exhaust fumes" instead a noun "Co".

Exhaust fumes noun - Gases ejected from an engine as waste products.

Co and exhaust fumes are semantically related in colorless odorless toxic gas topic. You can use "Co" instead a noun phrase "Exhaust fumes".