Handwipe Disclosing Method for Detecting the Presence of Lead

Lead (Pb) exposure can cause serious health concerns including abdominal pain, headaches, loss of appetite, memory loss, weakness, and other symptoms. Lead residues on human skin, especially on the hands of workers can be a significant health risk since such residues may be ingested during normal activities (e.g. eating, drinking, and smoking). A key component to reducing lead exposure is being able to identify areas of lead contamination.

US Centers for Disease Control and Prevention (CDC), National Institute for Occupational Safety and Health (NIOSH) researchers developed a method to detect lead on surfaces, including skin, using a handwipe system and a chemical test to effect a color change if lead is present. A handwipe is used to collect any lead contamination on the surface. Then the lead is solubilized with an aqueous acid solution and treated with rhodizonate or sulfide anions. When lead is detected, the color changes from pink to red (when rhodizonate anions are used) or from brown to black (where sulfide anions are used).

This invention can be used to test surfaces including human skin, floors, walls, windowsills, etc. It can be used to inform employers and workers on potential lead contamination, as well as evaluate lead removal efforts. This technology can also be used in conjunction with another CDC NIOSH invention involving wipes and methods for removal of lead. Combined, these two technologies can “close the loop” by both detecting and decontaminating skin and other surfaces contaminated with lead.