Influence of biochar produced from negative pressure-induced carbonization on transformation of potentially toxic metal(loid)s concerning plant physiological characteristics in industrially contaminated soil.

Soil contamination and its subsequent impact on the food chain is a pressing challenge in the present day. The application of biochar has demonstrated a significant and positive effect on soil health, thereby enhancing plant growth and development. However, the application of biochar (BC) produced from negative pressure-induced carbonization to mitigate metal(loid) contamination is a new strategy that has been studied in current research. Results depicted that the application of biochar derived from the negative pressure carbonization (vacuum-assisted biochar (VBC) has a significant (p ≤ 0.05) positive impact on plant growth and physiological characteristics by influencing immobilization and speciation of metal(loid) in the soil system. Moreover, the interactive effect of VBC on physiological characteristics (photosynthesis, gas exchange, and chlorophyll contents) and antioxidant activities of maize (Zea mays L.) was significantly (p ≤ 0.05) positive by confining the translocation and movement of metal(loid)s to the aerial part of the maize plant. X-ray diffraction (XRD) provided information on the structural and chemical changes induced by the VBC-500 °C explaining metal(loid) adsorption onto mineral surfaces and complexation that can affect their mobility, availability, and toxicity in the contaminated soil. Fourier transform infrared spectroscopy (FTIR) further provided a more detailed understanding of the metal(loid)s and biochar complexation mechanisms influenced by VBC-based functional groups -OH, C-Hn, -COOH, CO, C-O-C, CC, C-O, C-H, OH, and C-C in the binding process. These results suggest that the application of biochar prepared at 500 °C under negative pressure-induced carbonization conditions to the soil is the most efficient way to reduce the uptake and transfer of metal(loid)s by influencing their mobility and availability in the soil-plant system.

Spectroscopic fingerprinting, pollution characterization, and health risk assessment of potentially toxic metals from urban particulate matter.

The unprecedented stride of urbanization and industrialization has given rise to anthropogenic input of tiny particulates into the air. Urban particulate matter (PM) armored with potentially toxic metals (PTMs) could be lethal to the environment and human health. Therefore, the present study was planned to investigate the spectroscopic fingerprinting, pollution status and health risk of PM-associated PTMs collected from ten functional areas of Lahore, Pakistan. The diverged results of studied qualitative and quantitative analyses showed distinct compositional and pollution characteristics of PTMs in urban PM with respect to selected functional areas. The XRD results evident the fractional presence of metal-containing minerals, i.e., pyrite (FeS2), calcite (CaCO3), zinc sulfate (ZnSO4), and chalcostibite (CuSbS2). Several chemical species of Zn, Pb, and As were found in PM of various functional areas. However, morphologies of PM showed anthropogenic influence with slight quantitative support of PTMs presence. The cumulative representation of PTMs pollution of all selected areas depicted that Cd was heavily polluted (Igeo=3.21) while Cr (Igeo=1.82) and Ni (Igeo=2.11) were moderately polluted PTMs. The industrial area having high pollution status of Cd (Igeo=5.54 and EF=18.07), Cu (Igeo=6.4 and EF=32.61), Cr (Igeo=4.03 and EF=6.53), Ni (Igeo=5.7 and EF=20.17), and Zn (Igeo=4.87 and EF=11.27) was prominent among other studied areas. The PTMs were likely to pose a high non-cancerous risk in IndAr (HI = 7.48E+00) and HTV (HI = 1.22E +00) areas predominantly due to Zn with HQ > 1. However, Cr was prominent to cause cancerous risks with values beyond the tolerable range (1.00E-04 to 1.00E-06).

Interactive assessment of lignite and bamboo-biochar for geochemical speciation, modulation and uptake of Cu and other heavy metals in the copper mine tailing.

This study was designed to examine the combined effect of bamboo-biochar (BC) and water-washed lignite (LGT) at copper mine tailings (CuMT) sites on the concentration of Cu and other metals in pore water (PW), their bioavailability, and change in geochemical speciation. Rapeseed (first cropping-season) and wheat (second cropping-season) were grown for 40-days each and the influence of applied-amendments on both cropping seasons was observed and compared. A significant increase in pH, water holding capacity (WHC), and soil organic carbon (SOC) was observed after the applied amendments in second cropping-seasons. The BC-LGT significantly reduced the concentration of Cu in PW after second cropping seasons; however, the concentration of Pb and Zn were increased with the individual application of biochar and LGT, respectively. BC-LGT and BC-2% significantly reduced the bioavailability of Cu and other HMs in both cropping seasons. The treated-CuMT was subjected to spectroscopic investigation through X-ray photoelectron spectroscopy (XPS), Fourier transform Infrared spectroscopy (FTIR), and X-ray powder diffraction (XRD). The results showed that Cu sorption mainly involved the coordination with hydroxyl and carboxyl functional groups, as well as the co-precipitation or complexation on mineral surfaces, which vary with the applied amendment and bulk amount of Mg, Mn, and Fe released during sorption-process. The co-application of BC-LGT exerted significant effectiveness in immobilizing Cu and other HMs in CuMT. The outcomes of the study indicated that co-application of BC-LGT is an efficacious combination of organic and inorganic materials for Cu adsorption which may provide some new information for the sustainable remediation of copper mine tailing.

Geochemical fractionation and spectroscopic fingerprinting for evaluation of the environmental transformation of potentially toxic metal(oid)s in surface-subsurface soils.

The contamination of soil by toxic metal(oid)s has emerged as a major concern worldwide, particularly in developing countries. A metals behavior in the soil environment is influenced by organic matter, mineral phases, and oxidation states in which a particular metal exists. However, the spectroscopic evidence of metal(oid)s interactions in soil with organic matter and mineral phases can induce an extensive understanding. The surface and sub-surface soils (0-50 cm) from four sites of upper Indus basin, Pakistan, were collected and analyzed by using FTIR (Fourier-transform infrared spectroscopy), XRD (X-ray diffraction) and XPS (X-ray photoelectron spectroscopy) in addition to ICP-MS (inductively coupled plasma mass spectrometry) and geochemical fractionation. Geochemical fractionation of metal(oid)s indicated that As, Cu, Ni, Pb, and Zn were mostly found in the potentially bioavailable fractions. However, an increase in the residual fraction was observed from top to bottom. The absorption bands of FTIR spectra were divided into three spectral regions 700-400, 1700-800, and 3700-2800 cm-1. The soil was found rich in organic matter and capable of retaining metals as abundant peaks were observed in the mid-infrared region. The mineralogical analysis of soil samples testified silicon oxides and zeolite as major mineral phases. The XPS spectra showed broad peaks of As(III), As2O3, As4S4, PbO2, and PbCo3. The study concludes that the source identification of metal(oid)s in the upper Indus is crucial to find out the particular source of contamination in the soil.

Recent trends in advanced oxidation process-based degradation of erythromycin: Pollution status, eco-toxicity and degradation mechanism in aquatic ecosystems.

Wide spread documentation of antibiotic pollution is becoming a threat to aquatic environment. Erythromycin (ERY), a macrolide belonging antibiotic is at the top of this list with its concentrations ranging between ng/L to a few µg/L in various global waterbodies giving rise to ERY-resistance genes (ERY-RGs) and ERY- resistance bacteria (ERY-RBs) posing serious threat to the aquatic organisms. ERY seems resistant to various conventional water treatments, remained intact and even increased in terms of mass loads after treatment. Enhanced oxidation potential, wide pH range, elevated selectivity, adaptability and greater efficiency makes advance oxidation processes (AOPs) top priority for degrading pollutants with aromatic rings and unsaturated bonds like ERY. In this manuscript, recent developments in AOPs for ERY degradation are reported along with the factors that affect the degradation mechanism. ERY, marked as a risk prioritized macrolide antibiotic by 2015 released European Union watch list, most probably due to its protein inhibition capability considered third most widely used antibiotic. The current review provides a complete ERY overview including the environmental entry sources, concentration in global waters, ERY status in STPs, as well as factors affecting their functionality. Along with that this study presents complete outlook regarding ERY-RGs and provides an in depth detail regarding ERY's potential threats to aquatic biota. This study helps in figuring out the best possible strategy to tackle antibiotic pollution keeping ERY as a model antibiotic because of extreme toxicity records.

Morpho-chemical characterization and source apportionment of potentially toxic metal(oid)s from school dust of second largest populous city of Pakistan.

Interior settled dust is one of the greatest threats of potentially toxic metal(oid)s (PTMs) exposure to the children, especially in the school environment. Therefore, it is more worthy of having in-depth knowledge of compositional characteristics of school dust. Forty schools were selected of Lahore city for dust sampling. The school dust was analyzed to determine the PTMs (As, Cd, Cr, Cu, Ge, Mo, Ni, Pb, Sb, Sn, Sr, V, and Zn) concentrations using ICP-MS. The morphological characteristics, PTMs speciation, and mineralogy of school dust were examined using SEM with EDS, XPS, and XRD, respectively. Moreover, the geo-accumulation index (Igeo), potential ecological risk index (PERI), and multivariate statistical analysis were employed to assess the pollution levels, ecological risk, and source identification of PTMs, respectively. The Igeo indicated a heavily-extreme pollution level of Cd (Igeo = 4.92), moderate-heavy pollution of Zn (Igeo = 3.22), and Pb (Igeo = 2.78), and slight-moderate pollution of Cr (Igeo = 1.62), and Cu (Igeo = 1.53). The ecological risk has been found extremely high for Cd and moderately high for Pb and As, while potential ecological risk found extremely high posed by cumulatively all selected PTMs. Multivariate statistical analysis showed that sources of PTMs comprise of natural processes as well as several anthropogenic processes like vehicular emissions, agricultural and industrial activities. The SEM, XRD, and XPS analyses demonstrated the presence of airborne particles and PTMs containing minerals with several toxic chemical species in school dust. This study can help to develop strategies to reduce school indoor pollution and hence to establish an eco-friendly learning environment for children.

Critical risk analysis of metals toxicity in wastewater irrigated soil and crops: a study of a semi-arid developing region.

Toxic elemental exposure through consumption of contaminated crops is becoming a serious concern for human health. Present study is based on the environment and health risk assessment of wastewater irrigated soil and crops in a semi-arid region Faisalabad, Pakistan. The concentrations of potentially toxic elements (Cu, Cr, Mn, Fe, Pb, Zn, Ni) were analysed by atomic absorption spectrometer in five different crops (Corn, rice, wheat, sugarcane and millet), while, their topsoil's and multi targeted risks analysis were assessed. Results showed, the mean values of Pb and Zn were higher in crop than Food and Agriculture Organization guidelines for food additives and contaminants. A strong positive correlation was found among wastewater and crop's toxic metals (r2 values in Cu, Zn, Pb, Ni and Cr were 0.913, 0.804, 0.752, 0.694, 0.587 respectively). Whereas, a strong correlation was also found among soil and wastewater lead (r2 = 0.639). The calculations of Nemerow Integrated Pollution Index (NIPI) showed the soil samples maximum pollution limit (NIPI > 3) and Potential Ecological Risk Index (PERI) was found to be higher than maximum limit (PERI > 600) for all samples. While, for non-carcinogenic risk, Hazard Index (HI) values in adult were near threshold (HI > 1) for all crop samples. In children, the HI values for Corn, Rice and Wheat were above threshold limit and for Sugarcane and Millet, these were near to threshold. Cancer risk values for Cr found higher than safe limit (1 × 10-6) in adult and children for crop samples. Crop irrigation by wastewater irrigation is a prominent alternative option for water scarce countries, however prior testing and treatment of such wastewater streams must be employed to minimize the adverse impacts on human health and environment.

A comprehensive review of climate change impacts, adaptation, and mitigation on environmental and natural calamities in Pakistan.

The devastations and damages caused by climate change are apparent across the globe, specifically in the South Asian region where vulnerabilities to climate change among residents are high and climate change adaptation and mitigation awareness are extremely low. Pakistan's low adaptive capacity due to high poverty rate, limited financial resources and shortage of physical resources, and continual extreme climatic events including varying temperature, continual flooding, melting glaciers, saturation of lakes, earthquakes, hurricanes, storms, avalanches, droughts, scarcity of water, pest diseases, human healthcare issues, and seasonal and lifestyle changes have persistently threatened the ecosystem, biodiversity, human communities, animal habitations, forests, lands, and oceans with a potential to cause further damages in the future. The likely effect of climate change on common residents of Pakistan with comparison to the world and their per capita impact of climate change are terribly high with local animal species such as lions, vultures, dolphins, and tortoise facing extinction regardless of generating and contributing diminutively to global GHG emissions. The findings of the review suggested that GHG emissions cause climate change which has impacted agriculture livestock and forestry, weather trends and patterns, food water and energy security, and society of Pakistan. This review is a sectorial evaluation of climate change mitigation and adaption approaches in Pakistan in the aforementioned sectors and its economic costs which were identified to be between 7 to 14 billion USD per annum. The research suggested that governmental interference is essential for sustainable development of the country through strict accountability of resources and regulation implemented in the past for generating state-of-the-art climate policy.

Estimating the pollution characteristics and health risks of potentially toxic metal(loid)s in urban-industrial soils in the Indus basin, Pakistan.

The Indus Basin Irrigation Network (IBIN) plays a vital role in the agricultural system of Pakistan, irrigating seventeen million hectares of cultivated areas. Rapid urbanization, industrialization, and agricultural activities along the Indus basin have influenced the soil quality and human health; it is, therefore, critical to know its pollution characteristics. Soil samples from Indus basin, i.e., Abbottabad (ABT), Haripur (HRP), Attock (ATC), and Islamabad (ISB) have been analyzed for the total contents of potentially toxic metal(loid)s (PTMs) in the top layer. The topsoil samples from 0 to 10 cm depth have been further investigated using different pollution indices and human health risk assessment models. The contamination degree of soil pollution was highest in ISB (33.75), followed by ABT (25.30) and ATC (23.57). The assessment of the daily intake of PTMs by children and adults through different pathways revealed ingestion as the significant exposure pathway. Cr was found to be the major element posing non-carcinogenic health risks to children at ATC whereas the non-carcinogenic risks posed by all other PTMs were within the safe limit. Furthermore, life-time carcinogenic risks for Ni followed by Cr and Cd were greatly exceeded at all locations and As at ATC and ISB for both age groups, but comparatively children were found to be at a higher risk of carcinogenicity. Hence, efficient remediation strategies are needed to reduce the increasing content and health risks of PTMs in the Indus basin.

Investigating the drinking and surface water quality and associated health risks in a semi-arid multi-industrial metropolis (Faisalabad), Pakistan.

Urban areas under the influence of multi-industrial activities with arid and semi-arid environments witness the significant increase in environmental pollution especially in the water sector. The present study evaluated the water quality and associated health risk assessment through heavy metal pollution. Drinking (n = 48) and surface (n = 37) water samples were collected from semi-arid multi-industrial metropolis, Faisalabad, Pakistan. Physio-chemical and biological parameters and different metals (Al, As, Ba, Cd, Cr, Cu, Fe, Pb, Ni and Zn) were investigated using standard procedures and multivariate water quality assessments. Many physio-chemical and biological parameters and metals especially arsenic were exceeding the permissible limit of Punjab environmental quality standards and the World Health Organization. The results from water quality index showed that < 56% samples have poor, < 8% have very poor and < 6% have unsuitable water quality for drinking purposes. Water quality for the Gugera Branch Canal was found suitable with medium sodium (alkalinity) and salinity hazards, while it was found poor with magnesium absorption ratio. Hazard quotient (HQ) values for arsenic were found at the threshold level (HQ > 1) and carcinogenicity was found in case of arsenic and chromium (1 × 10-4) in adults and children. Semi-arid weather combined with different anthropogenic activities and unusual water features provoked metal contamination. Results of the present study can deliver basic information for effective management of water in the most populous and industrial areas.

A comprehensive review on environmental transformation of selenium: recent advances and research perspectives.

Selenium (Se) is an important micronutrient and essential trace element for both humans and animals, which exist in the environment ubiquitously. Selenium deficiency is an important issue worldwide, with various reported cases of its deficiency. Low selenium contents in some specific terrestrial environments have resulted in its deficiency in humans. However, high levels of selenium in the geochemical environment may have harmful influences and can cause a severe toxicity to living things. Due to its extremely narrow deficiency and toxicity limits, selenium is becoming a serious matter of discussion for the scientists who deals with selenium-related environmental and health issues. Based on available relevant literature, this review provides a comprehensive data about Se sources, levels, production and factors affecting selenium bioavailability/speciation in soil, characteristics of Se, biogeochemical cycling, deficiency and toxicity, and its environmental transformation to know the Se distribution in the environment. Further research should focus on thoroughly understanding the concentration, speciation, Se cycling in the environment and food chain to effectively utilize Se resources, remediate Se deficiency/toxicity, and evaluate the Se states and eco-effects on human health.

Biomonitoring and health risks assessment of trace elements in various age- and gender-groups exposed to road dust in habitable urban-industrial areas of Hefei, China.

The current study investigates the concentration of eleven trace elements in biomaterials including hair (85) and nails (85) along with seventy five (75) road dust samples collected from a healthy population of habitable urban-industrial areas of Hefei, China. The samples were acid digested and analyzed using ICP-MS for trace elements content. The mean concentration of Elements followed descending order of Zn > Mg > Fe > Cr > Al > Sn > Sr > Ti > Cu > As > Cd and Mg > Zn > Fe > Cr > Al > Sn > Ti > Cu > Sr > As > Cd in hair and nails, respectively. Overall, the concentration of elements was found to be high in female subject as compared to male. The concentration of trace elements in hair and nail exceeded the maximum permissible limits in most cases. The corresponding mean values from dust samples were fairly high as compared to background values of trace elements. Middle age groups (21-30 years and 31-40 years) were observed to be the most vulnerable there-by posing a high health risk, as the concentration of trace elements was significantly high in these groups except for Al, which was detected high in age < 20 in case of both male and female. A significantly high correlation was found between trace elements in biomaterials and those detected in dust samples. In hair samples, a significantly positive correlation was noticed for As with Mg, Zn, Sn and Fe, Sn/Mg and Mg/Ti. In the case of nails, a significant correlation was observed for elements like Al, Mg, Zn, Cr, and Cu. The Cluster and principal component analysis revealed industrial and vehicular emissions as main sources for trace elements exposure in humans.

Evaluation of floor-wise pollution status and deposition behavior of potentially toxic elements and nanoparticles in air conditioner dust during urbanistic development.

The study was undertaken to investigate deposition behaviors of various size-segregated particles and indoor air quality using dust accumulated on the air conditioner filter acting as a sink for PTEs and nanoparticles that can pose a significant health risk. However, the particulate matter size and chemical composition in AC dust and its relationship with PTEs remains uncertain. Current study aims to investigate the PTEs and nanoparticles composition of AC dust using different analytical approaches including ICP-MS, XRD, XPS, SEM/TEM along with EDS and Laser Diffraction particle size analyzer. The mean concentration of PTEs like Al, As, Cd, Cu, Li, Pb, Sb, Se, Sn, Ti, V and Zn exceeded the corresponding background value. Pb, As, Sn, Sb, Cd were categorizing under geo-accumulation index class IV. Most of the particles were found to be > 100 µm and it decreased significantly with increase in floor altitude. A significantly negative correlation was found between particles size and PTEs concentration showing a significant increase in PTEs content with decrease in particles size. The XPS results showed dominant peaks for TiO2, Ti-O-N, As2O3, Fe+3, Fe+2, Al-OH and Al203. Additionally, As, Pb, Si and Fe were dominant metallic nanoparticles identified using SEM/TEM along with EDS.