Still existing arsenals of chemical weapons (CW) pose not only security threats for possible use in hostilities by state actors or misuse by terrorists but also safety threats to humans and biota due to leakages and possible accidents. The Chemical Weapons Convention (CWC) commits the States Parties (SPs) to destroy CW using technologies taking into consideration human health and environmental protection. It does not allow methods, routinely used up to the 1970s, such as earth burial, open-pit burning, and sea dumping. Long-term health and environmental threats and some accidents that have already occurred in the known localities of the sea-dumped and earth-buried arsenals of Nazi-German armed forces in the Baltic Region and of Imperial Japanese forces in the Far East Region are analyzed according to the impact of major CW and ammunition types (i.e., sulfur mustard--HD, tabun--GA, arsenicals--DA, DC, DM, arsine oil, and chloroacetophenone--CN). Any possible operations and handling with CW envisaged by the CWC as well as their verification are summarized taking into account the health threat they pose. CW and toxic armament waste to be destroyed and applied technologies (both developed and under current use in operational CW destruction facilities [CWDF]) are reviewed as are systems of health safety and environmental protection of the destruction/demilitarization stems from the extraordinary high toxicity of supertoxic lethal agents in man and biota. Problems of currently used Russian and U.S. standards for maximum allowable workplace concentrations and general population limits and possibilities of their determination by available analytical instrumentation are discussed.