Boron trifluoride etherate is a corrosive and toxic liquid which develops a lot of fog when exposed to air. When it comes in contact with water it vigorously decomposes to hydrofluoric acid and boric acid.
Substance of poor quality can be recycled by a simple vacuum distillation (Kp10 = 46 °C).
Small quantities may be deactivated by slow addition to sodiumhydrogencarbonate solution. Dispose bigger amounts witout any treatment in a separate bottle.