RESEARCH ON DIOXIN COMPOUNDS IN ASH SAMPLES COLLECTED AT MAN XA ALUMINUM RECYCLING VILLAGE, BAC NINH PROVINCE

The study investigated to determine several dioxin compounds in the ash samples collected at Man Xa aluminum recycling village (Van Mon commune, Yen Phong district, Bac Ninh province). Dioxin compounds were extracted by Thermo ASE 350 Solvent Accelerator (Thermo, USA) and analysed using HRGC/HRMS gas chromatography equipment (Thermo Trace 1310, Thermo, USA) coupled with DFS high resolution mass spectrometry system. Results, the average concentrations of dioxin/furan compounds in fly ash and bottom ash samples were 16.9-979 (ng/kg d.w) and 0.422-10.2 (ng/kg d.w), respectively. The total equivalent toxic concentrations of dioxin/furan compounds in fly ash samples ranged from 284 to 423 ng TEQ/kg d.w, while those in bottom ash samples were from 3.17 to 7.93 ng TEQ/kg d.w. Interestingly, these values are within the permissible limits according to the national technical regulation on hazardous waste thresholds (QCVN 07:2009/BTNMT). However, the exploitation and use of fly ash and bottom ash for different purposes, that can cause environmental pollution and pose potential risks to human health if not controlled and managed appropriately. Therefore, it is necessary to expand research to minimize the impacts of dioxin/furan compounds present in fly ash and bottom ash on the environment and human life, gradually helping authorities have the basis to issue sanctions to better monitor and manage the activities of metal recycling villages in general and Man Xa aluminum recycling village in particular.