White lined chipboard, also referred to as: WLC, GD, GT or UD, is a grade of paperboard typically made from layers of waste paper or recycled fibers. Most often it comes with two to three layers of coating on the top and one layer on the reverse side. Because of its recycled content it will be grey from the inside.The main enduse for this type of board is for packaging of frozen or chilled food, cereals, shoes, toys and others. Health risks have been associated with using recycled material in direct food contact. Swiss studies have shown that recycled material can contain significant portions of mineral oil, which may migrate into packed foods. (Mineral oil levels of up to 19.4 mg/kg were found in rice packed in recycled board.)