The type of bonding between oxygen and silicon is not harmful to the environment. In fact, silicon dioxide (SiO2), which is formed by the bonding of silicon and oxygen, is a very common and abundant mineral in the Earth's crust. It is the main component of sand, quartz, and many other rocks and minerals. Silicon dioxide is also used in a wide variety of products, such as glass, ceramics, and electronics. It is generally considered to be a safe and non-toxic material.