officials later confirmed that samples taken from the site of the attack had tested positive for a small amount of
mustard agent, in low concentration.
Encompassing 23,000 acres, PCD is responsible for storing 2,600 tons of
mustard agent in approximately 780,000 munitions.
forces had detected a sulfur
mustard agent on fragments of a shell that ISIS had fired against Kurdish forces earlier this month.
They have frequently used chlorine and
mustard agent against the Kurds and Iraqi security forces around Mosul over the last year and chemical weapons are likely to play a role in their defence of the city.
Medical Management Guidelines for Blister Agents such as Sulfur
Mustard Agent H or HD (C4H8Cl2S), Sulfur
Mustard Agent HT.
The shell initially tested positive for a
mustard agent, but two subsequent tests have been inconclusive and the device is undergoing further tests, Navy Captain Davis told reporters.
A group of US forces inspected the fragments afterwards and took a small sample of a suspicious "tar-like, black, oily" substance, which initially tested positive for
mustard agent but then tested negative in a subsequent examination, the official said.
The IS has fired a small rocket at a military base that hosts hundreds of US troops near Mosul, with the shell testing positive "for a
mustard agent.
Following reports of a possible
mustard agent attack on US troops south of Mosul on Tuesday and confirmed chemical weapons attacks on Kurdish forces in the past, there are also concerns that IS might resort to such tactics in its defence of the city.
When Libya joined the Chemical Weapons Convention in 2004, the Gaddafi government declared a host of material it held in its chemical arsenal, including a vast store of bulk sulphur
mustard agent.
The jihadist group fired rockets suspected of carrying a
mustard agent last month from Bashir on Taza Khurmatu, another town in the northern province of Kirkuk.
Army began destroying the nation's largest remaining stockpile of chemical weapons Wednesday, using explosives to rip open a container of
mustard agent inside a sealed chamber and then flooding it with another chemical to neutralize it.
mustard agent - a toxic war gas with sulfide based compounds that raises blisters and attacks the eyes and lungs; there is no known antidote