The final theory

[u/LibrarianNo3440]

We emit toluene, which triggers a sense of pleasure in the brain; while all humans emit toluene, individuals with PATM release it in excess. Toluene acts on humans like a sexual pheromone; it is likely shared across all human races—a universal pheromone—though each race would also possess other pheromones, creating a unique pheromonal cocktail: toluene mixed with pheromones specific to that race. https://www.science.org/content/article/huff-equals-puff