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Environmental impact
Polycarbonate, as seen above, has a wide variety of uses and is present in many products, including compact discs. According to the Environmental Protection Agency (EPA), 100,000 pounds (about 45,000,000 grams) of compact discs each month become useless, unwanted, or outdated. 80 percent of that mass comes from polycarbonate and therefore accounts for 36,000,000 grams of that total.

Chemical breakdown
Polycarbonate is used in a large amount of consumer products because it is stable and durable. The stability of polycarbonate ensures that products will not break down while in use and also prevents them from being biodegraded in the environment. Polycarbonate can break down both physically and chemically, through both physical weathering and thermal and photodegradation processes. The main thermal degradation pathway is shown below. This process is done at very high temperatures (340-380 degrees C) and therefore is not a great contributor to the degradation of polycarbonate in the natural environment.

The cleavage of the polymer chain at different points causes a number of possible products through photodegradation processes. Several of these cleavage points and products are shown below. These figures are modified from a peer reviewed article and have been changed to show the general idea of the photodegradation pathways of polycarbonate. They do not show the complete chemistry, instead they show the general cleavage points and products of the polycarbonate polymer, to keep with simplicity of the concept.

Physical breakdown
In addition to thermal and photodegradation, polycarbonate can break down physically, into smaller and smaller pieces. These pieces can have negative affects on wildlife, if they are to consume them. Ingestion may lead to death from starvation and debilitation, with a reduced quality of life and lowered reproductive performance. This can have a drastic effect on economies, especially in coastal areas. Louisiana is responsible for producing 25% of the United States' seafood. The ingestion of polycarbonate by marine life in Louisiana alone could have a large impact on the United States' seafood consumption. With the consumption of affected seafood by humans, polycarbonate can be introduced into the human body, having negative health effects.

Formation of bisphenol A
As shown above, polycarobonate can photodegrade into many different compounds. One of the many constituents that polycarbonate can degrade into is Bisphenol A (BPA). The process by which this is done is shown below. This process is done at high temperature in the presence of water.

Effects of bisphenol A
Bisphenol A can have health effects on humans as well as animals. According to a 2003 study by the Centers for Disease Control and Prevention (CDC), BPA was found in detectable amounts in 93% of people studied. Health effects associated with BPA are described in detail in the Health effects section on the Bisphenol A page.

Solutions
The amount of polycarbonate in the environment can be reduced by the reuse and recycling of products containing the polymer. Different processes of plastic recycling are detailed on the plastic recycling page.