Analysis of environmental sustainability of e-waste in developing countries - a case study from Pakistan.

The electronic waste generation rate is increasing drastically at a rate of 3 to 5% per year in developing countries. The aim of this study is to analyze the environmental sustainability and economic benefits of such e-waste management in the developing economies like Pakistan. The life cycle assessment (LCA) method has been employed for streamlined impact analysis of the end-of-life processing of e-waste focusing mainly on laptop computers and liquid crystal display (LCD) desktop computers in Pakistan. The method of cumulative exergy extraction from the natural environment (CEENE) has also been deployed for the relative assessment of resources' consumption of e-waste recycling versus landfilling scenario. The determined impact scores are 1.79E + 03 kg CO2 eq., 7.19E-07 kg CFC-11 eq., 1.02E + 03 kg 1,4-DCB, 7.13E + 01 kg 1,4-DCB, and 3.41E-03 kg Cu eq. in climate change potential, stratospheric ozone depletion, ecotoxicity potential, human noncarcinogenic potential, and mineral resource depletion impact categories, respectively. The results of CEENE analysis reveal that approximately 80% of the impact on natural resources is reduced by the efficient recycling of e-waste. The comparative assessment of respective scores for current and target material weight recovery (MWR) indicators represented that by increasing the MWR indicator by 33.8% for laptop computers and by 27.2% for LCD computers, the country will achieve an annual economic benefit of US $191.56 million. This is greatly significant for a transitional shift towards e-waste revalorization while realizing the objectives of sustainable resource consumption. Innovative improvement measures ensuring economically feasible, energy-efficient, and environment friendly waste collection, treatment, and recycling practices present an invaluable opportunity for developing countries.

Assessment of human health risk associated with the presence of pesticides in chicken eggs

The presence of pesticides in the environment is highly toxic to environment and human health. Aim of the study was determination, quantification and assessment of associated health risk due to presence of pesticide residues in chicken eggs using high pressure liquid chromatography. HPLC method was successfully employed and validated. From collected samples pesticides were extracted in presence of petroleum ether and acetonitrile. Bifenthrin and Difenoconazole residues were found in all samples with different concentration exceeding maximum residue limits (MRL) of Codex Alimentarius Commission. However imidacloprid was not detected in any sample. Concentration of bifenthrin in house egg samples ranged from 0.256206 to 4.112387 mg/kg while in poultry farm samples it varied from 1.5862 to 5.80796 mg/kg. Difenoconazole was found in concentration of 0.02835 mg/kg, 1.7668 mg/kg, 3.7205 mg/kg, 21.8937 mg/kg 21.9835 mg/kg, 19.26407 mg/kg in samples collected from houses while and in poultry farm samples its detected concentration was 10.939 mg/kg, 12.3296 mg/kg, 29.3617 mg/kg, 18.6116 mg/kg, 40.0523 mg/kg and 19.2335 mg/kg. Concentrations of both pesticides Bifenthrin and Difenoconazole exceeded the MRLs (0.05 mg/kg). Health risk index surpassed 1 (the cut off value) for Difenoconazole in seven samples while for Bifenthrin values were less than 1, indicating the possibility of potential medium to long term health risk associated with ingestion of contaminated eggs.(AU)