Decomposition of aluminum arsenide produces hazardous arsine gas and arsenic fumes. Adding phosphine or arsine results in slower deposition, while adding diborane increases the deposition rate. Diborane increases the growth rate, but arsine and phosphine decrease it. Igniting this gas mixture would oxidize any arsine present into arsenic and water vapor. The parent compounds are arsine and arsenic acid. The toxicity of arsine is distinct from that of other arsenic compounds. Gallium arsenide, another semiconductor, forms upon co-pyrolysis of trimethylgallium and arsine. This sensitive test detects arsine generated in the presence of arsenic. The arsenic in the sample is first converted to arsine gas by treatment with hydrogen. Potassium arsenite also reacts with acids to yield toxic arsine gas. Cyanide-based blood agents irritate the eyes and the respiratory tract, while arsine is nonirritating. Arsine, stibine and bismuthine are highly toxic, thermally unstable, and colourless gases. Arsine has a very faint garlic odor detectable only at greater than fatal concentrations. They are moderate oxidizers that can be reduced to arsenites and to arsine. Arsine damages the red blood cells which deliver oxygen throughout the body.