to health problems. It was an unscrupulous practice in some small factories but it became rampant in China and forced many honest manufacturers to label their boxes "lead-free" after the scandal went mainstream in 2013. In powdered tetragonal litharge form, it can be mixed with linseed oil and then boiled to create a weather-resistant sizing used in gilding. The litharge would give the sizing a dark red color that made the gold leaf appear warm and lustrous, while the linseed oil would impart adhesion and a flat durable binding surface. PbO is used in certain condensation reactions in organic synthesis. PbO is the input photoconductor in a video camera tube called the Plumbicon. Health issues Lead oxide may be fatal if swallowed or inhaled. It causes irritation to skin, eyes, and respiratory tract. It affects gum tissue, the central nervous system, the kidneys, the blood, and the reproductive system. It can bioaccumulate in plants and in mammals. References External links Case Studies in Environmental Medicine - Lead Toxicity ToxFAQs: Lead National Pollutant Inventory - Lead and Lead Compounds Fact Sheet Webelements PbO Amphoteric compounds Lead(II) compounds Oxides