The two-week conference has already gotten off to a rocky start, with member states trading accusations. Up until now, the job of the OPCW had been to document the use of chemical weapons - but a series of high-profile nerve agent attacks led to the vote giving the OPCW the authority to attribute blame.
From early next year, the watchdog will start apportioning responsibility for chemical attacks in Syria. Russia, Iran and Syria are opposed to this and at The Hague summit Moscow called the OPCW to be subjected to "open-ended" scrutiny before it attributes blame for chemical weapons attacks.
This led countries which want to see the OPCW's powers grow -- including the US and Britain -- to accuse Russia and China of seeking to stall the watchdog in its new role.
US Ambassador Kenneth Ward warned against allowing a “new era of chemical weapons use to take hold” while Britain said any move to limit the OPCW would be "unacceptable".
The language from the Russian and Syrian envoys in response was heated. Russia said that claims Damascus had used chemical weapons in Syria, and that Moscow had used Novichok against former Russian spy Sergei Skripal in Salisbury, were a “scam” and “out and out lies”.
The Syrian Deputy Foreign Minister Faisal Mekdad went further ... accusing the West of hypocrisy: “You have taught people to use chemical weapons, you have used chemical weapons in the first two world wars. The Syrian government has never used chemical weapons.”
Hamish de Bretton-Gordon is a chemical weapons expert and a former commander of Britain's now disbanded Joint Chemical, Biological, Radiological and Nuclear Regiment. He says there has long been geopolitical disagreement over how the body should operate.
"It's thought the OPCW has really lacked teeth and some of the key protagonists like the Russians and the Syrians have vetoed any investigations the OPCW have done," he said.
"One must remember the OPCW is the UN body that investigates the Chemical Weapons Convention - or rather contraventions to that convention ... I think where they can attribute blame, then that will strengthen the Chemical Weapons Convention because what has happened since Obama's red line was broken in August 2013, chemical weapons have proliferated around the world and we must renew that red line and renew the 100-year taboo on the use of chemical weapons with all means that we have available."
The OPCW - recipient of the Nobel Peace Prize in 2013 - says that since 1997 it has overseen the elimination of 96 percent of the world's chemical weapons stockpiles.