Typical organic pollutants during thermal conversion process of waste lithium-ion batteries and its potential health risk assessment

In order to identify typical organic pollutants in waste lithium-ion batteries (LIB) and their thermal process by-products, and to assess the potential health risks of respiratory exposure to the occupational group, non-targeted screening analysis was conducted using both gas chromatography-high resolution mass spectrometry (GC-HRMS) and liquid chromatography-high resolution mass spectrometry (LC-HRMS). The results revealed that 115 organic compounds were identified in the waste LIB extract, predominantly aromatic compounds (34.8%) as well as lipids and lipid-like molecules (17.4%), including per- and poly-fluoroalkyl substances, organophosphate ester, and phthalates, which are known to pose health hazards. After the pyrolysis process at 550 °C in a nitrogen atmosphere, the variety of compounds in the waste LIB sample significantly decreased. However, 373 compounds were detected in the pyrolysis products, including a substantial number of polycyclic aromatic hydrocarbons (PAHs) and their derivatives, with a notable concentration of phenanthrene reaching 1 675 μg/m³ in the pyrolysis gas and pyrolysis oil. The incremental lifetime carcinogenic risk assessment of PAHs indicated that the pyrolysis gas products of the waste LIB sample could pose lifetime carcinogenic risks to the occupational group..