Portable chemical toilets are found at construction sites, festivals, parks, inside RVs... basically anywhere there isn't plumbing. They typically contain blue-dyed fluid which deodorizes waste, plus many contain disinfectants, such as formaldehyde, bleach, glutaraldehyde, nitrates, quaternary ammonia compounds and/or enzymes. Depending on the chemicals, the fluid may or may not give off toxic or irritating vapors, but in all cases, it's better to avoid spending too much time in a port-o-potty. Why? The methane evolved from the decomposing waste in chemical toilets and also outhouses actually has the potential to make you light-headed or even kill you.