Persistent organic pollutants (POPs) are organic compounds that are resistant to environmental degradation through chemical, biological, and photolytic processes. Because of their persistence, POPs bioaccumulate with potential significant impacts on human health and the environment. The effect of POPs on human and environmental health was discussed, with intention to eliminate or severely restrict their production, by the international community at the Stockholm Convention on Persistent Organic Pollutants in 2001.
[GHG] Precursor emissions are compounds that will react with other compounds to potentially form not only GHGs, but also other environmental pollutants and degrading agents. Acid rain is a direct result of just the right mix of precursor emissions.