With about 92 percent of the world's declared chemical weapons stockpiles destroyed, the watchdog agency overseeing the elimination of poison gas and nerve agents is looking now to counter emerging threats from extremist groups while still dealing with unfinished business in Syria.
The Organization for the Prohibition of Chemical Weapons is marking the April 29, 1997, entry into force of the Chemical Weapons Convention with a three-day conference starting Monday focusing on chemical safety and security.
It appears, in the future, extremists and criminals seem more likely than nations to launch chemical attacks.
"We want to capture the current security threats in regard to chemical weapons, especially from non-state actors,'' OPCW Director-General Ahmet Uzumcu told The Associated Press at the organization's headquarters in The Hague.
There have been repeated reports of chemical attacks in Syria's devastating civil war and a U.N.-mandated investigation is underway aimed at apportioning blame for nine cases in 2014 and 2015. A final report is expected shortly before the team's mandate ends in September.
In some of the cases, it's believed that chlorine was used in the attacks. The widely available substance is sold the world over for legitimate purposes such as water purification, but chlorine gas also was used in the first large-scale chemical weapons attack by German forces in World War I.
"The challenge will remain to prevent the use of toxic substances as a weapon,'' said Uzumcu, whose organization won the 2013 Nobel Peace Prize for its disarmament efforts.
The issue is not new, the OPCW has been considering it since the 9/11 attacks in the United States, but it has been brought into sharper focus by the attacks in Syria.
At the conference starting Monday, experts will discuss how to use the existing chemical weapons convention to tackle the problem and whether the OCPW needs to adapt to the new reality.
Ralf Trapp, a former OPCW staffer who is now an independent disarmament and non-proliferation consultant, says protecting people from attacks using readily available chemicals is a difficult balancing act.
"You always will have the dilemma that some of these chemicals are in very wide use,'' he said in a telephone interview. "If you over-regulate them or control them to the point where they can no longer be properly used, you're actually slowing down economic use. It's not going to work.''
Trapp warned that finding a way to deal with extremists has taken on new urgency with the rise of the Islamic State group in Syria and Iraq.
"Over time, you could expect that if they do decide to go for a chemical weapons program that they will in fact have the capability of investing time and money into it and develop something that would be much more sophisticated than what we see today,'' he said.
Meanwhile, the OPCW has yet to complete its work in Syria, which joined the organization in 2013 amid international outrage at a nerve gas attack on the outskirts of Damascus.
Syrian President Bashar Assad's government declared a 1,300-ton chemical weapons stockpile and 14 production facilities, triggering an unprecedented international operation to remove weapons and chemicals from the war-torn country and destroy them.
The weapons have been destroyed, as have 11 of the production plants, Uzumcu said, but member states of the OPCW have repeatedly questioned whether Assad declared everything in 2013.
"We are not yet there,'' Uzumcu said. "There are still questions. I am not able to say whether Syria has declared everything or whether Syria continues to possess some chemical weapons or some munitions. I hope that we will be able to clarify the remaining questions.''
He said Syrian officials are expected to visit The Hague in coming weeks to continue talks aimed at clarifying the situation.
Another key challenge for the OPCW is attempting to bring on board four remaining countries that have not joined the chemical weapons convention _ Egypt, Israel, North Korea and South Sudan.
Uzumcu believes it is only a "matter of time'' before South Sudan joins and says the change in the Mideast security landscape brought about by the Syrian war may ultimately lead to Israel and Egypt joining.
The reclusive regime in North Korea has so far ignored all attempts by Uzumcu to open a dialogue.
Trapp says getting Pyongyang on board will be tough because of the nuclear issue that dominates the disarmament agenda.
"Can you isolate the chemical weapons issue from the rest of the security situation on the Korean peninsula?'' he said "If you could do that, you could talk to the Koreans and try to get a process going. If you can't separate it from the rest, it becomes a ball in a much bigger game and you get the nuclear issue and a couple of other things and it becomes very complicated.''