Along with fibres, paper can contain a variety of inorganic and organic constituents, including up to 10,000 different chemicals, which can potentially contaminate the newly manufactured paper products. As an example, bisphenol A (a chemical commonly found in thermal paper) has been verified as a contaminant in a variety of paper products resulting from paper recycling. Groups of chemicals as phthalates, phenols, mineral oils, polychlorinated biphenyls (PCBs) and toxic metals have all been identified in paper material. Although several measures might reduce the chemical load in paper recycling (e.g., improved decontamination, optimized collection of paper for recycling), even completely terminating the use of a particular chemical (phase-out) might still result in its circulation in the paper cycle for decades. See also Deinked pulp cardboard Paper Tree-free paper Wood-free paper Environmental impact of paper USPS Post Office Box Lobby Recycling program References External links U.S. Environmental Protection Agency: Paper and Paperboard Products How to Make Recycled Paper – A tutorial for making your own recycled paper Waste Paper Recycling – How Paper Recycling works? Water conservation Forest conservation Recycling by material Energy conservation