chromated copper arsenate


chro·​mat·​ed copper arsenate ˈkrō-ˌmā-təd- How to pronounce chromated copper arsenate (audio)
: a chemical combination of chromium, copper, and arsenic used to protect wood against insects and decay
Then, in the 1930s, scientists found a way to infuse wood with a solution that included copper (toxic to the fungi that cause rot) and arsenic (then the most common insecticide). To ensure the protection would last and builders and the environment wouldn't be hurt, they also added chromium. It triggered a chemical reaction that locked the pesticides into the wood. The formula became known as chromated copper arsenate, or just CCA. But the industry called it pressure-treated because the chemicals were injected under great pressure.Curtis Rist
abbreviation CCA

Examples of chromated copper arsenate in a Sentence

Recent Examples on the Web For projects around homes, the main replacement was lumber treated with chromated copper arsenate, or CCA, which was introduced in the 1940s. Jeanne Huber, Washington Post, 17 Aug. 2020

These examples are programmatically compiled from various online sources to illustrate current usage of the word 'chromated copper arsenate.' Any opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback about these examples.

Word History

First Known Use

1962, in the meaning defined above

Time Traveler
The first known use of chromated copper arsenate was in 1962

Dictionary Entries Near chromated copper arsenate

Cite this Entry

“Chromated copper arsenate.” Dictionary, Merriam-Webster, Accessed 1 Oct. 2023.

Love words? Need even more definitions?

Subscribe to America's largest dictionary and get thousands more definitions and advanced search—ad free!