An Overview: PAH and Nitro-PAH Emission from the Stationary Sources and their Transformations in the Atmosphere

The scientific society is progressively aware of the adverse health effects caused by polycyclic aromatic hydrocarbons (PAHs) and nitrated PAHs (nitro-PAHs) from stationary sources, especially waste incinerators. They are mutagenic, persistent in the environment, and cause diseases and mortality worldwide. Nitro-PAHs have a higher carcinogenic potential than their parent PAHs; however, the scientific community's understanding of their properties and quantities in different matrices is still rudimentary. This is due to their infinitesimally lower concentrations in the ambient air and other environments compared to their parent PAHs. Herein, the limitations of most pretreatment and detection methods to quantify them are highlighted. The evolution of the state-of-the-art pretreatment and quantification techniques applied to evaluate PAHs and nitro-PAH concentrations accurately are discussed. This review highlights typical concentrations of PAH and nitro-PAH emitted from stationary sources especially waste incinerators. Formation processes, gas-particle partitioning, and indicative congeners are mentioned. The role of APCDS in controlling PAHs and nitro-PAHs and their fate in the environment are highlighted. Finally, challenges and an outlook on the research field are provided. The improved knowledge developed herein helps to understand the potential mutagenicity threat posed by PAHs and nitro-PAHs in the ambient air and other environments.