Yazar "Saqib, Zafeer" seçeneğine göre listele

Listeleniyor 1 - 2 / 2
  • Küçük Resim Yok
    Öğe
    Characterization and distribution of brominated flame retardants in soils from informal E-waste recycling facilities: insights from Pakistan
    (Springer, 2025) Kazim, Mureed; Saqib, Zafeer; Syed, Jabir Hussain; Odabasi, Mustafa; Kurt-Karakus, Perihan Binnur
    E-waste, a global environmental concern, particularly affects developing nations due to the rise in informal recycling practices. This leads to contamination of environmental matrices, posing threats to both ecosystems and human health. To assess this issue, we monitored brominated flame retardants (BFRs) in 164 samples (soil) from 32 informal e-waste operational locations and 9 background locations across nine mega cities of Pakistan from September 2020 to December 2021. The mean concentrations (ng/g) of & sum;27PBDEs (polybrominated diphenyl ethers), & sum;2PBB (polybrominated biphenyls), HBB (hexabromobiphenyl), and & sum;HBCDD (hexabromocyclododecane) were 176 ( 0.76-11141), 31.0 (0.65-58.0), 1.39 (0.01-42.8), and 12.0 (0.22-461), respectively. These levels were significantly higher (6 to tenfold) than those at background sites. Karachi, Faisalabad, Gujranwala, and Lahore exhibited high levels of all BFRs. Notably, BDE-209 (mean = 45.5 ng/g) ranged (0.13-1152 ng/g) exhibited higher level in soil samples. Seasonally, total Sigma BFR concentrations (ng/g) ranked higher in winter (11,620), followed by spring (3874), autumn (3139), and summer (1207) indicating a seasonal impact of recycling activities. The average daily dose for soil ingestion (ng/kg/day) was estimated for BDE-209 (0.10973) in Faisalabad, followed by BDE-47 (0.08616) and BDE-99 (0.06788) in Karachi. Our findings showed that these values were lower than RfD values, suggesting no ingestion risk from studied BFRs. However, the growing prevalence of such informal e-waste recycling facilities could lead to increased exposure to toxic chemicals in near future.
  • Küçük Resim Yok
    Öğe
    Informal E-waste recycling in nine cities of Pakistan reveals significant impacts on local air and soil quality and associated health risks
    (Elsevier Sci Ltd, 2024) Kazim, Mureed; Syed, Jabir Hussain; Saqib, Zafeer; Kurt-Karakus, Perihan Binnur; Iqbal, Mehreen; Nasir, Jawad; Odabasi, Mustafa
    The global increase in electronic waste (e-waste) has led to a rise in informal recycling, emitting hazardous heavy metals (HMs) that threaten human health and ecosystems. This study presents the first comprehensive assessment of HM levels in dry deposition and soils at proximity of forty (40) informal e-waste recycling sites across Pakistan, between September 2020 to December 2021. Findings reveal that Zn (1410), Pb (410) and Mn (231) exhibited the higher mean deposition fluxes (mu g/m2.day), derived from air samples, particularly in Karachi. Similarly, soils showed higher mean concentrations (mu g/g dw) of Mn (477), Cu (514) and Pb (172) in Faisalabad, Lahore, and Karachi, respectively. HMs concentrations were found higher in winter or autumn and lower in summer. In addition, HM levels were significantly (p = 0.05) higher at recycling sites compared to background sites year-round, highlighting the e-waste recycling operations as the major source of their emissions. The Igeo index indicated moderate to extremely contaminated levels of Cu, Pb, Cd, and Ni in Karachi, Lahore and Gujranwala. Ingestion was found as a leading human exposure route, followed by dermal and inhalation exposure, with Pb posing the greatest health risk. The Cumulative Incremental Lifetime Cancer Risk (ILCR) model suggested moderate to low cancer risks for workers. Strategic interventions recommend mitigating health and environmental risks, prioritizing human health and ecosystem integrity in Pakistan's e-waste management.