Bulgaria deposited its instrument of ratification of the PRTR Protocol on 15 January 2010, the first Member State to do so in the new calendar year. Bulgaria is the 23rd country and the 24th Party to join the treaty.

Bulgaria's deposit enables it to enjoy full rights and privileges of a Party at the upcoming first meeting of the Parties to the Protocol, scheduled to be held from 20-22 April 2010 in Geneva.