CCA (chromated copper arsenate) is a wood preservative containing chromium, copper, and arsenic, used to protect wood from decay and insect attack, but has been phased out for residential use due to health concerns.
Concerns about the risk of arsenic exposure led to the discontinuation of its use in residential applications in many countries, including the United States in 2003.
Proper disposal of CCA-treated wood is necessary to prevent further environmental contamination.
Burning CCA treated wood is also not recommended, as the smoke and ashes will contain high concentrations of arsenic.