Boron enters the environment mainly through the weathering of rocks, boric acid volatilization from seawater, and volcanic activity. Boron is also released from anthropogenic sources to a lesser extent. Anthropogenic sources include agricultural, refuse, and fuel wood burning, power generation using coal and oil, glass product manufacture, use of borates/perborates in the home and industry, borate mining/processing, leaching of treated wood/paper, and sewage/sludge disposal. Many of these sources are difficult to quantify.
Atmospheric emissions of borates and boric acid in particulate and vapour form occur as a result of volatilization from the sea, volcanic activity, and, to a lesser extent, mining operations, glass and ceramics manufacturing, the application of agricultural chemicals, and coal-fired power plants. Boron is not present in the atmosphere at significant levels; however, the total amount present in the atmosphere at any one time is significant owing to the huge volume of the atmosphere. Based on their water solubility, borates would not be expected to persist to a significant degree in the atmosphere.
Boron can be released into water and soil water through weathering processes and, to a much smaller extent, through anthropogenic discharges such as sewage outfalls.