Pencil thereby pushing a new tip to the top. Invented by Harold Grossman for Empire Pencil Company in 1967 and subsequently improved upon by Arthur D. Little for Empire from 1969 through the early 1970s; the plastic pencil was commercialised by Empire as the "EPCON" Pencil. These pencils were co-extruded, extruding a plasticised graphite mix within a wood-composite core. Residual graphite from a pencil stick is not poisonous, and graphite is harmless if consumed. Although lead has not been used for writing since antiquity, lead poisoning from pencils was not uncommon. Until the middle of the 20th century the paint used
White lead White lead White lead is the basic lead carbonate, 2PbCO·Pb(OH). It is a complex salt, containing both carbonate and hydroxide ions. White lead occurs naturally as a mineral, in which context it is known as hydrocerussite, a hydrate of cerussite. It was formerly used as an ingredient for lead paint and a cosmetic called Venetian Ceruse, because of its opacity and the satiny smooth mixture it made with dryable oils. However, it tended to cause lead poisoning, and its use has been banned in most countries. White lead compounds known as lead soap were also used as additive for lubricants