Many chemicals used in photographic processes give off hazardous vapours.
Other solutions produce potentially harmful gases such as formaldehyde, gluteraldehyde, hydroquinnone, ammonia, sulphur dioxide and hydrogen sulphide. Some ingredients can be corrosive. Exposure to these substances can affect the liver, lungs, kidneys, reproductive system, gastro-intestinal tract, or the central nervous system. Exposure may also cause dizziness, nausea, sore lips, headaches or chest pains in some people. Darkroom ventilation is often insufficient and badly designed.