PCBs and PCDD/Fs in soil from informal e-waste recycling sites and open dumpsites in India: Levels, congener profiles and health risk assessment

Paromita Chakraborty; Sakthivel Selvaraj; Masafumi Nakamura; Balasubramanian Prithiviraj; Alessandra Cincinelli; John J Bang

doi:10.1016/j.scitotenv.2017.11.083

PCBs and PCDD/Fs in soil from informal e-waste recycling sites and open dumpsites in India: Levels, congener profiles and health risk assessment

Sci Total Environ. 2018 Apr 15:621:930-938. doi: 10.1016/j.scitotenv.2017.11.083. Epub 2017 Dec 18.

Authors

Paromita Chakraborty¹, Sakthivel Selvaraj², Masafumi Nakamura³, Balasubramanian Prithiviraj², Alessandra Cincinelli⁴, John J Bang⁵

Affiliations

¹ SRM Research Institute, SRM University, Kattankulathur, Tamil Nadu 603203, India; Department of Civil Engineering, SRM University, Kattankulathur, Tamil Nadu 603203, India. Electronic address: paromita.c@res.srmuniv.ac.in.
² SRM Research Institute, SRM University, Kattankulathur, Tamil Nadu 603203, India.
³ Hiyoshi Corporation, Kitanosho 908, Omihachiman, Shiga 523-0806, Japan.
⁴ Department of Chemistry "Ugo Schiff", Via della Lastruccia, 3, 50019 Sesto Fiorentino, Florence, Italy.
⁵ Department of Environmental, Earth and Geospatial Science, NCCU, Durham, NC, USA.

PMID: 29223911
DOI: 10.1016/j.scitotenv.2017.11.083

Abstract

Growth of informal electronic waste (e-waste) recycling sector is an emerging problem for India. The presence of halogenated compounds in e-wastes may result in the formation of persistent organic pollutants like polychlorinated biphenyls (PCBs), polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) during recycling processes. We therefore investigated PCBs and PCDD/Fs in surface soils explicitly from the informal e-waste recycling sites and nearby open dumpsites of major metropolitan cities from four corners of India, viz., New Delhi (North), Kolkata (East), Mumbai (West) and Chennai (South). In the informal e-waste recycling sites, the range of Σ₂₆PCBs (0.4-488ng/g) and ƩPCDD/Fs (1.0-10.6ng/g) were higher than Ʃ₂₆PCBs (0.3-21ng/g) and ƩPCDD/Fs (0.15-7.3ng/g) from open dumpsites. In the e-waste sites, ƩPCDDs were found with increasing trend from ƩTetraCDD to OctaCDD, whereas ƩPCDFs showed a reverse trend. The dominance of PCDF congeners and maximum toxicity equivalents (TEQ) for both PCDDs (17pg TEQ/g) and PCDFs (82pg TEQ/g) at Mandoli in New Delhi has been related to intensive precious metal recovery process using acid bath. Among dumpsites, highest TEQ for PCDD/Fs was observed at Kodangaiyur dumpsite of Chennai (CN_DS-02, 45pg TEQ/g). Positive Matrix Factorization (PMF) model identified distinct congener pattern based on the functional activities, such as e-waste dismantling, shredding, precious metal recovery and open burning in dumpsites. E-waste metal recovery factor was loaded with 86-91% of PCB-77, -105, -114, -118 and 30% of PCB-126, possibly associated with the burning of wires during the copper extraction process. Almost 70% of the Ʃ₂₆PCB concentrations was comprised of the dioxin-like PCB congeners with a maximum concentration of 437ng/g at New Moore market in Chennai, followed by Wire Lane (102ng/g), in Mumbai. We speculate that PCB-126 might have resulted from combustion of plastic materials in e-waste stream and dumped waste.

Keywords: E-waste; High resolution gas chromatography mass spectrometry; PCBs; PCDD/Fs; PMF model; TEQ.

MeSH terms

Cities
Dibenzofurans, Polychlorinated / analysis*
Electronic Waste*
Environmental Monitoring
India
Polychlorinated Biphenyls / analysis*
Polychlorinated Dibenzodioxins / analysis*
Recycling*
Risk Assessment
Soil
Soil Pollutants / analysis*

Substances

Dibenzofurans, Polychlorinated
Polychlorinated Dibenzodioxins
Soil
Soil Pollutants
Polychlorinated Biphenyls