[quote=t2wave]
I don't see how breathing Earth's atmosphere would cause them to be more effective. They are chemicals that when inhaled the cause the brain to fire neurons, usually resulting in the body releasing a different chemical in the body.
[/quote]

It doesn't cause them to be more effective. Your brain adjusts to the chemical makeup of the air you breathe. Earth's atmosphere has a rather unique ratio of chemicals, so the brains of beings that breathe it for long enough have certain similarities. Anthony's pheromones are designed to affect the people whose brains are similar to his. It doesn't have to make perfect sense, scientifically, this entire RP is based off of comic books...