When I’m out walking my dogs of a morning on the local common ground, I’m finding more and more empty cans of Nitrous Oxide, not the little silver capsule type but big aerosols like you’d find in an automotive body repair shop, apparently they’re used in catering for whipping cream for cakes
It works by displacing the oxygen in your lungs being heavier than air, causing hypoxia
Prolonged and heavy use risks blood clotting and heart attacks