POPs are chemical substances that persist in the environment, bioacculumate through the food web, and pose a risk of causing adverse effects to the human health and the environment. Many POPs pose such significant threats to human health and the environment that on 22nd May 2001, the world’s government met in Sweden and adopted an international treaty aimed at restricting and ultimately eliminating their production, use, release and storage.

The Treaty called the Stockholm Convention on Persistent Organic Pollutants is a major achievement. It starts by immediately targeting 12 particularly toxic POPs for reduction and eventual elimination. More importantly, it sets up a system for tackling additional chemicals identified as unacceptably hazards.

Nepal has become the signatory country on the Stockholm Convention on Persistent Organic Pollutants, which was held on Stockholm from 22-23 May 2001. Nepal has signed the convention on 5 April 2002.The convention has not been ratified but the process of doing it is underway. Presently Global Environment Facility is helping Nepal to undertake project entitled "Nepal: Enabling Activities to facilitate early action on the implementation of the Stockholm Convention on Persistent Organic Pollutants (POPs)" with the agreement between United Nations Industrial Development organization (UNIDO) and Ministry of Population and Environment.