Biological Fluids Saliva, Semen and Urine Also Glow When Hit with a Black Light. Most Biological Fluids Contain Fluorescent Molecules to Help Them Glow. When...
Biological Fluids
Saliva, semen and urine also glow when hit with a black light. Most biological fluids contain fluorescent molecules to help them glow. When hunting down that spot where Fido urinated, use a black light in a dark room to find and clean it instead of your nose.
What liquids glow under black light?
Thiamine, riboflavin, niacin, fluids and vitamins shine under black light. Urine, semen and blood contain fluorescent molecules, so they also show up under black light. Interestingly, some cleaners and laundry detergents, scorpions, tonic water and antifreeze and teeth whiteners all also glow under black light.
The same holds for many organic substances, and most bodily fluids—including sweat, saliva, and urine—will shine when you put them under an ultraviolet “black light.” Semen happens to glow the brightest, however, on account of the particular mix of chemicals it contains.
Maya is a hardware enthusiast who tests and reviews smart home devices, smartphones, wearables, and audio gear. She focuses on practical consumer value and build quality.