Effects of salinity and temperature on seawater dissolution rate of initial detonation agent mercury fulminate

Mercury fulminate (HgFu) was used as an initial detonator for World War I and II munitions. Its presence in previously discarded and dumped munitions could potentially supply mercury pollution into coastal ecosystems where bygone weaponries reside. There is evidence that historical munitions have already contributed mercury pollution in coastal environments, and millions remain embedded in sediments and subjected to further weakening via corrosion under environmental conditions. Experiments were undertaken assessing HgFu dissolution under varying temperature and salinity conditions to constrain controls on mercury release into marine environments. Our results show that HgFu discharge is strongly temperature dependent, with dissolution rate constants increasing from ∼0.4 mg cm−2 d−1 at 5 °C to ∼2.7 mg cm−2 d−1 at 30 °C. No significant differences were observed between freshwater and seawaters up to 36 psu, except at 5 °C. These experiments provide a basis for modeling HgFu release from underwater munitions and its dynamics in coastal environments.