The COVID-19 pandemic has made everyone aware of the importance of keeping common surfaces clean.

The shortage of some commercial cleaning products has caused some people to try to make their own from whatever they have around the house, and that’s not a good idea.

“In medicine we have an expression, Primum Non Nocere, which means First, Do No Harm,” said Dr. Steven Dina, M.D., a medical director at Univera Healthcare. “As we seek to prevent potential harm from the COVID-19 virus and other germs, we may be inadvertently causing more.”

Mixing bleach with ammonia or any acid (drain cleaners, vinegar, glass cleaners, toilet bowl cleaners, etc.) can create toxic fumes that can be harmful or fatal. Here are some examples of dangerous chemical combinations.

¯ Bleach and vinegar, which equals chlorine gas. This can lead to coughing, breathing problems, burning and watery eyes. Chlorine gas and water also combine to make hydrochloric and hypochlorous acids. Chlorine gas is not something you want to be producing and inhaling in your home. Chlorine attacks the skin, mucous membranes, and respiratory system. At best, it will make people cough and irritate their eyes, nose and mouth. It can also give a chemical burn. At worst, it could be deadly if exposed to a high concentration or for those unable to get to fresh air.

¯ Bleach and ammonia, which equals chloramine. This can cause shortness of breath and chest pain. Chloramine burns the eyes and respiratory system and can lead to internal organ damage. If there is enough ammonia in the mixture, hydrazine may be produced. Hydrazine is not only toxic but also potentially explosive. The best-case scenario is discomfort; the worst-case scenario is death.

¯ Hydrogen peroxide and vinegar, which equals peracetic/peroxyacetic acid. This can be highly corrosive. Peracetic acid can irritate the eyes and nose and may give a chemical burn.

“Sometimes chemicals are stored in an unmarked bottle or placed in a bottle with different labeling,” said Dina. “Never use any chemical that you are not sure of its origin.”

Safely store chemicals in their original containers. Those with children should keep chemicals in cabinets with child-resistant locks, or high up and out-of-sight.

Those who experience any adverse or potential life-threatening reaction to cleaning supplies should call 911. The American Association of Poison Control Centers also offers 24-hour assistance for those who swallow or get splashed by something that may be harmful at 1-800-222-1222.

Dr. Steven Dina