Pencil Pencil A pencil is an implement for writing or drawing constructed of a narrow, solid pigment core inside a protective casing which prevents the core from being broken and/or from leaving marks on the user’s hand during use. Pencils create marks by physical abrasion, leaving behind a trail of solid core material that adheres to a sheet of paper or other surface. They are distinct from pens, which instead dispense liquid or gel ink onto the surface being marked. Most pencil cores are made of graphite powder mixed with a clay binder. Graphite pencils (traditionally known as 'lead pencils') are
Lead poisoning with lead in air, household dust, soil, water, and commercial products. Leaded gasoline has also been linked to increases in lead pollution. Some research has suggested a link between leaded gasoline and crime rates. Man made lead pollution has been elevated in the air for the past 2000 years. Lead pollution in the air is entirely due to human activity (mining and smelting). In adults, occupational exposure is the main cause of lead poisoning. People can be exposed when working in facilities that produce a variety of lead-containing products; these include radiation shields, ammunition, certain surgical equipment, developing dental x-ray