Chromated copper arsenate
（重定向自Tanalith）
Chromated copper arsenate (CCA) is a wood preservative that has been used for timber treatment since the mid-1930s. It is a mix of chromium, copper and arsenic (as Copper(II) arsenate) formulated as oxides or salts, and is recognizable for the greenish tint it imparts to timber. CCA was invented in 1933 by Dr. Sonti Kamesam, an Indian scientist, and was awarded its first patent (British) in 1934.