Emissions of polychlorinated naphthalenes during electric arc furnace steelmaking and their influencing factors

Abstract

Polychlorinated naphthalenes (PCNs) are emerging persistent organic pollutants (POPs) listed in the Stockholm Convention in 2015. PCNs were commercially produced and widely applied in transformer, capacitor oil and cable insulator in the early 20th century. PCNs are of persistency and can be globally transported. The widespread PCNs were reported to have hepatotoxicity and immunotoxicity, which were comparable to the toxicity of the notorious dioxins because of their similar structure. Currently, the toxicity of PCN congeners were characterized as the relative potency factors compared to 2,3,7,8-tetrachlorinated dioxins. The commercial PCN production was inhibited since 1980s because of their toxicity. PCNs dominantly acted as byproducts during thermal-related industrial processes, including the chemical production, waste incineration processes and metal smelting processes, and then be unintentionally emitted into the environment. The electric arc furnace steelmaking plants were one of the important sources, which were rarely researched currently on their POPs emission. Current limited data showed that the PCNs concentrations from the smelting process of electric arc furnace were relatively lower A c c e p t e d