1. Silicon: While silicon itself is not highly toxic, the processes used to purify and shape it into wafers can involve hazardous chemicals.
2. Gallium Arsenide: Used in high-speed and high-frequency applications, gallium arsenide is more efficient than silicon but is also more toxic. It poses risks if particles are inhaled or ingested during manufacturing or recycling.
3. Heavy Metals: Elements such as lead, cadmium, and mercury can be present in older transistor models. These metals are highly toxic and can cause severe health problems.
