[PHAHs levels in soil samples from the E-waste disassembly sites and their sources allocation]

Area of Science:

• Environmental Chemistry
• Toxicology
• Pollution Science

Context:

• Electronic waste (e-waste) recycling and disassembly generate significant environmental concerns.
• Persistent halogenated aromatic hydrocarbons (PHAHs) are a class of pollutants often found in e-waste.
• Understanding the distribution and sources of these contaminants is crucial for environmental risk assessment.

Purpose:

• To quantify the levels of polybrominated biphenyls (PBBs), polybrominated diphenyl ethers (PBDEs), and polychlorinated biphenyls (PCBs) in soil samples from e-waste disassembly sites.
• To identify the primary e-waste components responsible for the release of these pollutants.
• To compare contaminant levels in soils near disassembly sites with those in control sites.

Summary:

• Soil and e-waste residue samples (cable coating, stuffing powder, circuit boards) were analyzed for PBBs, PBDEs, and PCBs using GC-MS.
• Cable coating exhibited the highest PBB levels (35.25 ng/g), with low-brominated congeners comprising 38%.
• Stuffing powder showed the highest PBDE levels (29.71 ng/g), with PBDE153 and PBDE183 being predominant.
• PCBs were highest in cable coating (680.02 ng/g).
• Contaminant levels in soils from disassembly sites were significantly higher than control sites, confirming e-waste as the pollution source.

Impact:

• Provides critical data on the environmental contamination associated with e-waste disassembly.
• Highlights specific e-waste materials (cable coating, stuffing powder) as major sources of PBBs, PBDEs, and PCBs.
• Informs regulatory efforts and remediation strategies for managing e-waste pollution.
• Contributes to understanding the environmental fate and transport of these persistent organic pollutants.