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1.
Environ Geochem Health ; 45(5): 1617-1633, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-35552963

RESUMO

Heavy metals exposure through dust emissions pose a health risk to workers in coal and chromite mines. The processes involved in mining are noteworthy for the generation of heavy metal-contaminated dust which causes human health implications, especially to the workers that are mainly exposed to such toxins. This study determined pollution levels in coal and chromite mines and calculated the health risk of workers being exposed to heavy metal-contaminated dust. We used fractioned dust with particle sizes < 75, 75-106, and 107-150 µm to assess the pollution levels, anthropogenic impacts, geo-accumulation index, and enrichment factor for selected coal and chromite mines. Through a probabilistic approach, Monte Carlo simulations were used to determine health risks. The findings revealed that the smallest size dust fraction (< 75 µm) contained the highest metal concentrations. Ingestion was considered a prominent exposure route contributing to health risk. In the dust fraction (< 75 µm), chromite mines exhibited the highest Cr (340.6 mg/kg) and lowest Cd (8.4 mg/kg) concentrations. In coal mines, Mn (284.9 mg/kg) and Cd (2.1 mg/kg) were measured highest and lowest, respectively. Pollution assessment revealed dust to be moderately polluted. Health risk assessment showed that Cr in chromite mines exhibited a mean HI value of 1.16E + 00 that was higher than the safe level (HI > 1) having the potential to cause significant health risk to workers. In coal mines, the estimated total HI was 6E-1. Sensitivity analysis revealed concentration and exposure time to be the most influential parameters contributing to risk. Therefore, governmental and nongovernmental organizations must develop dust pollution control guidelines and mitigation measures to safeguard the health of mineworkers by limiting heavy metal exposure.


Assuntos
Poeira , Metais Pesados , Humanos , Poeira/análise , Cádmio/análise , Carvão Mineral/análise , Paquistão , Monitoramento Ambiental , Metais Pesados/análise , Medição de Risco , China
2.
Environ Geochem Health ; 46(1): 2, 2023 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-38071652

RESUMO

The potential of arsenic (As) tolerant and sensitive varieties of wheat (Triticum aestivum L.) has yet to be explored despite of alarming situation of arsenic toxicity. To fill this gap, the study aimed to explore the role of antioxidants, phytochelatins, and ascorbate-glutathione for As tolerance in wheat. A total of eight varieties were exposed to different arsenate treatments (0, 1, 5, 10, 50, 100, 200, 500, 1000, 2000, and 10,000 µM) initially to screen effective treatment as well as contrasting varieties via Weibull distribution frequency for further analysis. The Weibull analysis found 200 µM as the most effective treatment in the present study. Selected varieties were analyzed for accumulation of total As and As speciation, oxidative stress (malondialdehyde, hydrogen peroxide), antioxidants (superoxide dismutase, catalase, peroxidase), phytochelatins, and ascorbate-glutathione cycle (glutathione-S-transferase, glutathione reductase, glutathione peroxidase, ascorbate peroxidase). Tolerant varieties showed less accumulation and translocation of total As, arsenate, and arsenite to the shoots compared with sensitive varieties under 200 µM treatment. Low concentration in tolerant varieties correlated with better growth and development response. Tolerant varieties showed higher induction of metabolites (glutathione, phytochelatins) compared to sensitive ones. Furthermore, tolerant varieties showed better performance of antioxidant and ascorbate-glutathione cycle enzymes in response to As exposure. The findings of the present study provided great insight into the wheat tolerance mechanism upon As exposure between contrasting varieties.


Assuntos
Arsênio , Arsênio/toxicidade , Arsênio/metabolismo , Triticum/genética , Triticum/metabolismo , Arseniatos , Fitoquelatinas/metabolismo , Fenômica , Plântula/metabolismo , Antioxidantes/metabolismo , Glutationa/metabolismo , Estresse Oxidativo , Catalase/metabolismo , Superóxido Dismutase/metabolismo , Peróxido de Hidrogênio/metabolismo
3.
Environ Monit Assess ; 195(12): 1556, 2023 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-38036894

RESUMO

Leather tanneries are known for chemical laden work environments and pulmonic complaints among workers. This study presents an analysis of tannery micro-environments emphasizing on size-based variation in composition of particulate matter and consequent respiratory dysfunctions. Qualitative (FTIR, SEM-EDX) and quantitative assessment (elemental composition, carbon forms) of PM10 and 2.5 has been employed. For lung function evaluation of workforce, spirometry with ATS proprieties was used. The peak concentrations of both PM10 and 2.5 have been found at PU, FU, and B&S. The LTCR for only Cr is high for both PM2.5 and PM10. HQ was high for Al, Cr, and Mn for both PM sizes. The maximum organic and secondary organic carbon in PM10 was found at FU and in PM2.5 at PU. The varied PM composition included carbohydrate (B&S, WMO), ether (S&S, P&S) and hydroxyl (B&S, S&S, P&S), proteins, polyenes, vinyl groups (S&S, P&S, FU), alcohols (PU and FU), and aldehyde present at PU. These results were armored by high organic and total carbon concentrations for the same sites. Therefore, PM are classified into biogenic (carbonaceous: microbial and animal remains) from PU and WMO, incidental (industrial, mixt physico-chemical character) from PU, FU, WMO, B&S and P&S, and geogenic (crustal mineral dust) from RHT, B&S, PU, and P&S. Furthermore, increase in metal concentrations in PM10 (Cr, Mn, Co, Ni, V, As, Be, Ba, and Cd) and PM2.5 (As, Pb) while TC, OC, and SOC in PM2.5 caused depreciation overall lung function. The exposure to biogenic and incidental PM nature are key cause of pulmonic dysfunction.


Assuntos
Poluentes Atmosféricos , Material Particulado , Humanos , Material Particulado/análise , Poluentes Atmosféricos/análise , Monitoramento Ambiental , Poeira/análise , Carbono/análise , Tamanho da Partícula
4.
Environ Geochem Health ; 44(11): 3929-3951, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34751868

RESUMO

Arsenic (As), and fluoride (F-) are potent contaminants with established carcinogenic and non-carcinogenic impacts on the exposed populations globally. Despite elevated groundwater As and F- levels being reported from various regions of Pakistan no biomonitoring study has been reported yet to address the co-exposure impact of As and F- among school children. We aimed to investigate the effects of these two contaminants on dental fluorosis and intelligence quotient (IQ) along with the induction of oxidative stress in rural children under co-exposed conditions. A total of 148 children (5 to 16 years old) from the exposed and control group were recruited in the current study from endemic rural areas of Lahore and Kasur districts, Pakistan having elevated As and F- levels in drinking water than permissible limits. We monitored malondialdehyde and its probable association with antioxidants activity (SOD, CAT, and GR) as a biomarker of oxidative stress. GSTM1/T1 polymorphisms were measured to find the impact of As on health parameters. Mean urinary concentrations of As (2.70 vs. 0.016 µg/L, P < 0.000) and F- (3.27 vs. 0.24 mg/L, P < 0.000) as well as the frequency of dental fluorosis were found elevated among the exposed group. The cases of children with lower IQ were observed high in the exposed group. Additionally, lower concentrations of antioxidants (SOD, CAT, and GR) were found suggesting high susceptibility to F- toxicity. The findings suggest that F- accounted for high variations in health parameters of children under the co-exposure conditions with As.


Assuntos
Arsênio , Água Potável , Fluorose Dentária , Estresse Oxidativo , Humanos , Arsênio/toxicidade , Água Potável/química , Fluoretos/toxicidade , Fluorose Dentária/epidemiologia , Inteligência/efeitos dos fármacos , Malondialdeído , Paquistão/epidemiologia , Superóxido Dismutase , Pré-Escolar , Criança , Adolescente
5.
Environ Res ; 196: 110168, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-32919972

RESUMO

This article has been withdrawn at the request of the editor. The Publisher apologizes for any inconvenience this may cause.

6.
Int J Phytoremediation ; 23(6): 619-631, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33232176

RESUMO

Current study explored the effects of municipal sewage (MS) irrigation on heavy metal phyto-accretion, biochemical responses and human health risks of diverse wheat genotypes along with recycled municipal sewage (RMS). Mean concentrations of PO43-, NO3--N, chemical oxygen demand, biological oxygen demand, K, Co, Cu, Cd, Cr and Ni were found higher in MS than irrigation criteria. This led to significant increase in heavy metal contents in roots, stem and grains of MS irrigated wheat genotypes compared to RMS and control treatments. No adverse health risk effects for individual or multiple metals were recorded in RMS irrigated wheat genotypes on grounds of lowest heavy metal accumulation. Multivariate techniques i.e. principal component analyses (PCA) and hierarchical agglomerative cluster analyses (HACA) identified tolerant (inefficient metal accumulators) and sensitive (efficient metal accumulators) wheat genotypes in MS and RMS. Tolerant wheat genotypes showed lowest accumulation of heavy metals, efficient biochemical mechanisms to combat oxidative stress and lower health risks to adults/children. Cultivation of identified tolerant wheat genotypes is recommended in areas receiving municipal wastes to reduce human and environmental health risks. Moreover, genetic potential of identified tolerant wheat genotypes from MS and RMS can be utilized in breeding heavy metal tolerant wheat germplasm worldwide.


Assuntos
Metais Pesados , Poluentes do Solo , Biodegradação Ambiental , China , Monitoramento Ambiental , Genótipo , Humanos , Metais Pesados/análise , Medição de Risco , Esgotos , Solo , Poluentes do Solo/análise , Triticum/genética
7.
Environ Geochem Health ; 43(11): 4441-4458, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-33871746

RESUMO

Increased E-waste generation during recent times has become a global concern, especially for developing countries that are at receiving end from the developed countries. Their improper handling and lacking management practices in developing countries including Pakistan are contributing enormous addition of toxicants into the environment and affecting the health of exposed workers associated with E-waste recycling activities. A systematic cross-sectional study was designed comprising workers associated with E-waste recycling activities in Peshawar city, Pakistan. The study aimed to investigate metal concentrations in dust, particulate matter and urine of exposed workers and correlate with oxidative stress and glutathione S-transferases genotypes (GSTM1 and GSTT1) that play a role in detoxification of metals in humans. A total of 120 blood samples comprising dismantlers (n = 52), repairers (n = 21), smelters (n = 17) and controls (n = 30) were collected. Results showed that metal concentrations were significantly higher in the dust (P = 0.020), particulate matter (P = 0.021) and urine samples (P = 0.00) as compared to controls. We observed significant increase in MDA (P = 0.00) and decrease in SOD (P = 0.00) and CAT (P = 0.00) levels among exposed subjects as compared to controls. Additionally, GSTT1 null genotype was more significantly associated with the dismantlers (P = 0.02). The study shows that E-waste workers are exposed to high level of toxic metals through dust and particulate matter, resulting in significant oxidative stress and related health implications, while GSTT1 null polymorphism is associated with increased susceptibility to these metals and induced health outcomes.


Assuntos
Resíduo Eletrônico , Metais Pesados , Estudos Transversais , Genótipo , Glutationa Transferase/genética , Metais Pesados/toxicidade , Estresse Oxidativo , Paquistão
8.
Environ Res ; 183: 109191, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32062182

RESUMO

In this study, exposure to arsenic (As), lead (Pb), cadmium (Cd), copper (Cu) and zinc (Zn) was investigated in the blood, pectoral muscles and tail feathers of two terrestrial (spotted owlet; Athena brama and bank myna; Acridotheres ginginianus) and two aquatic (cattle egret; Bubulcus ibis and pond heron; Ardeola grayii) bird species inhabiting Pakistan. Food chain specimens, as well as the dietary proxies δ15N and δ13C, were also analyzed to validate potential trophic and dietary transfers of metals and As in birds. Zn was found to be the most prevalent metal in the tissues of birds followed by Pb, As, Cu, and Cd. The bioaccumulation of metals and As was higher in tail feathers reflecting the combined effect of both endogenous and exogenous contamination. Pectoral muscle and blood harbored lower levels of As and metals, indicating less recent exposure through diet. Aquatic birds feeding at higher trophic levels accumulated significantly higher concentrations of metals and As in their tissues (P < 0.05) and, therefore, may be at a greater risk of metal and As toxicity than terrestrial birds. Linear regression model depicts δ15N as a strong predictor of metals and As levels in the tissues of both aquatic and terrestrial birds, followed by the δ13C dietary proxy. All metals in aquatic species, except for Cd, as well as terrestrial species, except for Cu, exhibit bioaccumulative potential through the food chain (Trophic transfer factor: TTFs > 1) indicating potential harmful consequences for birds. Elevated concentrations of metals and As in tissues may cause harmful effects in birds potentially leading to declines in their populations.


Assuntos
Arsênio , Dieta , Metais Pesados , Animais , Aves , Bovinos , Biomarcadores Ambientais , Exposição Ambiental , Monitoramento Ambiental , Plumas , Cadeia Alimentar , Paquistão
9.
J Environ Manage ; 271: 111030, 2020 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-32778310

RESUMO

Pharmaceutically active compounds are newly recognized micropollutants which are ubiquitous in aquatic environment mainly due to direct discharge of treated and untreated wastewater from wastewater treatment plants. These contaminants have attracted mounted attention due to their toxic effects on aquatic life. They disrupt biological processes in non-target lower organisms upon exposure. Biodegradation, photo-degradation, and sorption are key processes which determine their fate in the environment. A variety of conventional and advanced treatment processes had been extensively investigated for the removal of pharmaceuticals from wastewater. However, due to structural complexity and varying operating parameters, complete removal seems ideal. Generally, due to high energy requirement of advanced treatment technology, it is considered cost ineffective. Transport of pharmaceutical compounds occurs via aquatic channels whereas sediments and aquatic colloids play a significant role as sinks for these contaminants. The current review provides a critical understanding of fate and toxicity of pharmaceutical compounds and highlights their vulnerability and occurrence in South Asia. Antibiotics, analgesics, and psychiatric drugs were found predominantly in the water environment of South Asian regions. Despite significant advances in understanding pharmaceuticals fate, toxicity, and associated risks since the 1990s, still substantial data gaps in terms of monitoring, human health risks, and legislation exist which presses the need to develop a more in-depth and interdisciplinary understanding of the subject.


Assuntos
Preparações Farmacêuticas , Poluentes Químicos da Água/análise , Ásia , Monitoramento Ambiental , Humanos , Águas Residuárias , Água
10.
Waste Manag Res ; 38(12): 1379-1388, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32812514

RESUMO

The present study quantified environmental impacts of the Rawalpindi Waste Management Company (RWMC) value chain in Pakistan for three consecutive years (2015-2018) using a cradle-to-grave life cycle assessment (LCA) approach. Energy potential from municipal solid wastes (MSW) was also predicted till the year 2050. Based on a functional unit of 1.0 tonne of MSW, the study analyzed inputs and outputs data through SimaPro v.8.3 applying CML 2000 methodology and cumulative exergy demand indicator (CExD). LCA revealed that operational activities of RWMC mainly contributed to marine aquatic ecotoxicity, i.e. 8962.83 kg1,4-DBeq t-1 MSW, indicating long-range transport of petrogenic hydrocarbons from the company's fleet gasoline combustion. Similarly, human toxicity potential, global warming potential and freshwater aquatic ecotoxicity potential were also found to be significant, i.e. 18.14 kg1,4-DBeq t-1 MSW, 15.79 kgCO2eq t-1 MSW and 6.22 kg1,4-DBeq t-1 MSW, respectively. The CExD showed that company activities consumed 827.14 MJ t-1 MSW exergy from nature, and gasoline used in MSW transport was the most exergy-intensive process, using 634.47 MJ exergy per tonne MSW disposed of. Projections for energy generation potential up to the year 2050 showed that MSW of Rawalpindi city will have the potential to produce 3901 megawatt of energy to fulfill the energy needs of the country. Possible stratagems to reduce environmental impacts from the municipal solid waste management (MSWM) value chain of RWMC include curtailing dependency on petrogenic and fossil fuels in mobile sources, optimization of waste collection methods and dumping routes, inclining attention toward suitable wastes-to-energy conversion technology and opting for a holistic approach of MSWM in Pakistan.


Assuntos
Eliminação de Resíduos , Gerenciamento de Resíduos , Cidades , Meio Ambiente , Humanos , Paquistão , Resíduos Sólidos/análise
11.
Environ Sci Technol ; 53(7): 3464-3470, 2019 04 02.
Artigo em Inglês | MEDLINE | ID: mdl-30844251

RESUMO

Although polychlorinated biphenyls (PCBs) have been banned for several decades, they are still detected with elevated levels due to their unintentional production from combustion and industrial thermal processes (UP-PCBs). To investigate the composition and current levels of UP-PCBs and understand which sources are controlling PCB burdens in ambient atmosphere, air samples were collected from August 2012 to August 2015 at a background site in east China. An unexpected high abundance of PCB47+48+75 was observed to be the predominant congener with an average concentration of 786 ± 637 pg/m3. It accounted for 48 ± 16% of ΣPCBs, followed by PCB51 (10 ± 4%), PCB11 (8 ± 6%), and PCB68 (7 ± 3%). Seasonal variations with high levels in summer and lowest levels in winter were observed for PCB47+48+75, 51, and 68. These tetrachlorobiphenyl congeners were strongly correlated with temperature ( r2 > 0.7), suggesting the control of temperature-dependent volatilization processes from contaminated surfaces. The decreased occurrence of PCB47+48+75, 51, and 68 in commercial products and their negative correlations (| r| < 0.35) with polycyclic aromatic hydrocarbon (PAHs) and weak correlation with other PCB congeners suggested unique unintentional sources that differ from combustion and industrial thermal processes or pigment, such as the use of polymer sealant, for PCB47+48+75, 51, and 68 in the ambient air.


Assuntos
Poluentes Atmosféricos , Bifenilos Policlorados , Atmosfera , China , Monitoramento Ambiental
12.
Ecotoxicol Environ Saf ; 170: 195-204, 2019 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-30529619

RESUMO

Waste dumping sites are considered as significant disposal pathway for waste contaminants including pesticides. In the present study OCPs were analyzed in soils of waste dumping sites of Pakistan. The mean concentrations of OCPs were in the order: ∑DDTs>∑HCHs>∑Endosulfan>∑HCB>Heptachlor. Order of overall ∑OCPs contamination with respect to location was Lahore>Sukkur>Karachi>Kamoki>Faisalabad>Hyderabad>Losar>Gujrat>Peshawar. Distribution of OCPs in solid waste dumping site was mainly influenced by textural classes, input history and pollution source. Soil texture was the dominant factor for retention of OCPs, whereas TOC and black carbon has not significantly impacted the concentrations of OCPs. Diagnostic ratios indicated the historical input, anaerobic degradation pathway and use of technical mixtures of DDTs in majority of waste dumping sites whereas for HCHs recent as well as past usage of technical mixture was prevalent in most of the areas. Regression analysis revealed a weak positive correlation of OCPs with socioeconomic indices (HDI, Population, waste generation) which is linked with history of use of these contaminants in the respective areas. Forecasted waste generation quantity for the year 2026 showed that waste generation amount will get doubled by the year 2026 suggesting the need properly designed waste management system.


Assuntos
Hidrocarbonetos Clorados/análise , Praguicidas/análise , Solo/química , Instalações de Eliminação de Resíduos , DDT/análise , Endossulfano/análise , Monitoramento Ambiental , Poluição Ambiental/análise , Heptacloro/análise , Paquistão , Medição de Risco , Poluentes do Solo/análise , Fuligem/análise , Análise Espacial , Sulfetos/análise
13.
Int J Phytoremediation ; 20(11): 1152-1161, 2018 Sep 19.
Artigo em Inglês | MEDLINE | ID: mdl-30156922

RESUMO

Design and implementation of wastewater treatment is inevitable due to toxic effects of wastewater irrigation on crops, soil and human health. Current investigation is the pioneer attempt on full-scale hybrid constructed wetland system (HCWS) built for municipal wastewater treatment from Pakistan. HCWS was comprised of vertical sub-surface flow constructed wetland (VSSF-CW) and five phyto-treatment ponds connected in series. Higher environmental risk was associated with untreated municipal wastewater usage in irrigation as estimated through discharge of metals to recipient soils. Treatment efficiency percentages recorded for HCWS reclaimed water quality parameters were, i.e., EC (56.68), TDS (56.86), alkalinity (39.67), chloride (39.68), sulfate (46.73), Na (28.80), Mn (65.24), Cr (78.07), Ni (81.02), BOD (68.74), total hardness (19.56), Fe (70.09), phosphate (55.40), Pb (80.48), COD (63.64), Mg (17.24), K (60.05), Co (100), Cu (67.73), Zn (59.97), Cd (100), and Ca (21.47) respectively. Wastewater treatment in HCWS was due to aquatic plants [Phragmites australis Cav. Trin. ex Steud., Canna indica L. Typha latifolia L., and Hydrocotyle umbellata L.], microbial activities and substrate based wetland processes. The HCWS treated water was well under irrigation standards and recommended for safer crop production in water scarce regions.


Assuntos
Águas Residuárias/análise , Poluentes Químicos da Água/análise , Irrigação Agrícola , Biodegradação Ambiental , Paquistão , Eliminação de Resíduos Líquidos , Áreas Alagadas
14.
Pak J Pharm Sci ; 31(2): 575-579, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29618450

RESUMO

The aim of this study was to determine antioxidant activity of Brassica oleracea (Cabbage), Brassica rapa (Turnip) and Raphanus sativus (Radish). All of the three selected vegetables were ultrasonically extracted in water and acetone. The antioxidant activity was determined by DPPH and H2O2. Highest phenolic, flavonoid and flavonol contents were found among water extract of Raphanus sativus, Brassica oleracea and Brassica rapa respectively. Highest %age of DPPH inhibition was exhibited by water extract of Brassica rapa and highest OH◦ radical scavenging activity was shown by water extract of Raphanus sativus.


Assuntos
Antioxidantes/farmacologia , Flavonoides/análise , Fenóis/análise , Extratos Vegetais/farmacologia , Verduras/química , Acetona/química , Antioxidantes/química , Compostos de Bifenilo/química , Flavonoides/química , Flavonóis/análise , Sequestradores de Radicais Livres/química , Sequestradores de Radicais Livres/farmacologia , Radical Hidroxila/química , Picratos/química , Extratos Vegetais/análise , Extratos Vegetais/química , Água/química
15.
Environ Sci Technol ; 51(23): 13895-13905, 2017 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-29134799

RESUMO

Informal e-waste recycling activities have been shown to be a major emitter of organic flame retardants (FRs), contributing to both environmental and human exposure to laborers at e-waste recycling sites in some West African countries, as well as in China and India. The main objective of this study was to determine the levels of selected organic FRs in both air and soil samples collected from areas with intensive informal e-waste recycling activities in Karachi, Pakistan. Dechlorane Plus (DP) and "novel" brominated flame retardants (NBFRs) were often detected in high concentrations in soils, while phosphorus-based FRs (OPFRs) dominated atmospheric samples. Among individual substances and substance groups, decabromodiphenyl ether (BDE-209) (726 ng/g), decabromodiphenyl ethane (DBDPE) (551 ng/g), 1,2-bis(2,4,6-tribromophenoxy) ethane (BTBPE) (362 ng/g), and triphenyl-phosphate (∑TPP) (296 ng/g) were found to be prevalent in soils, while OPFR congeners (5903-24986 ng/m3) were prevalent in air. The two major e-waste recycling areas (Shershah and Lyari) were highly contaminated with FRs, suggesting informal e-waste recycling activities as a major emission source of FRs in the environment in Karachi City. However, the hazards associated with exposure to PM2.5 appear to exceed those attributed to exposure to selected FRs via inhalation and soil ingestion.


Assuntos
Resíduo Eletrônico , Monitoramento Ambiental , Retardadores de Chama , África Ocidental , China , Éteres Difenil Halogenados , Humanos , Índia , Paquistão
16.
Rev Environ Contam Toxicol ; 240: 1-30, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-26809717

RESUMO

Polycyclic aromatic hydrocarbons (PAHs) are consistently posing high risks to human/biota in developing countries of South Asia where domestic areas are exposed to biomass burning and commercial/industrial activities. This review article summarized the available data on PAHs occurrence, distribution, potential sources and their possible risks in the key environmental matrices (i.e., Air, Soil/Sediments, Water) from South Asian Region (SAR). Available literature reviewed suggested that PAHs concentration levels were strongly influenced by the monsoonal rainfall system in the region and it has been supported by many studies that higher concentrations were measured during the winter season as compared to summer. Biomass burning (household and brick kilns activities), open burning of solid wastes and industrial and vehicular emissions were categorized as major sources of PAHs in the region. Regional comparison revealed that the contamination levels of PAHs in the water bodies and soil/sediments in SAR remained higher relatively to the reports from other regions of the world. Our findings highlight that there is still a general lack of reliable data, inventories and research studies addressing PAHs related issues in the context of environmental and human health in SAR. There is therefore a critical need to improve the current knowledge base, which should build upon the research experience from other regions which have experienced similar situations in the past. Further research into these issues in South Asia is considered vital to help inform future policies/control strategies as already successfully implemented in other countries.


Assuntos
Hidrocarbonetos Policíclicos Aromáticos/toxicidade , Biota , Sedimentos Geológicos/análise , Humanos , Hidrocarbonetos Policíclicos Aromáticos/análise , Medição de Risco , Poluentes do Solo/análise , Poluentes Químicos da Água/análise
17.
Environ Res ; 152: 26-42, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-27741446

RESUMO

In this review article, we have compiled and reviewed the previously published available literature on environmental distribution, behaviour, fate and regional trends of legacy and emerging flame retardants (FRs) including brominated (BFRs), organo-phosphate (OPFRs), novel brominated flame retardants (NBFRs) and dechlorane plus (DP) in the freshwater ecosystem. Transport and fate is discussed briefly with the evidences of de-bromination, sedimentation and accumulation in biota. De-bromination of BDE-209 is considered of concern because the lower brominated congeners are more toxic and mobile thus posing increased risk to the freshwater ecosystem. The available data on temporal and spatial trends as yet, is too few to show any consistent trends, enabling only general conclusions to be drawn. There is a lack of temporal studies in Asia, while, overall the trends are mixed, with both increasing and decreasing concentrations of BFRs and OPFRs. OPFRs and NBFRs have replaced classical BFRs (polybrominated diphenyl ethers (PBDEs)) in some countries but the amount of PBDEs in the environment is still considerable. Knowledge gaps and recommendations for future research are discussed emphasizing on further monitoring, advanced analytical methodologies, and risk assessment studies to completely understand the science of flame retardants in the freshwater ecosystem.


Assuntos
Retardadores de Chama/análise , Poluentes Químicos da Água/análise , Ecossistema , Água Doce
18.
Environ Toxicol ; 32(4): 1183-1190, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-27463516

RESUMO

Polychlorinated biphenyls (PCBs) are a group of chemicals that persist in the environment, indoors, and humans. Lung exposure to airborne and food contaminants, such as PCBs, may cause possible lung disorders, such as cancer. In the present study, we investigated the effects of structurally different lower chlorinated (≤4Cl), noncoplanar PCB40, and coplanar PCB77 on human lung fibroblast cell line (HELF) cell proliferation, cell cycle progression, and possible molecular mechanisms. Noncoplanar PCB40 and coplanar PCB77 exhibited concentration- and time-dependent biphasic dose-response effects on HELF cell proliferation. Noncoplanar PCB40 and coplanar PCB77 induced 23 and 45% cytotoxicity at higher concentrations than the control. The flow cytometry analysis showed that exposure to PCB40 caused a significant increase in time spent in the G1 phase but decreased length of the S phase in a concentration- and time-dependent manner, whereas PCB77 exposure decreased time spent in the G1 and S phases but increased time spent in the G2 phase. Western blot analysis indicated that PCB77 increased the expression of cyclin E, CDK2, p21, and caspase-9, while PCB40 decreased the expression of these proteins (except CDK2 and p21). An increase in CDK expression after exposure to PCB77 suggests that it may cause carcinogenic effects on HELF cells at higher doses. Our results also demonstrate that the different cytotoxic effects induced by coplanar and nonplanar PCBs were correlated with their structural characteristics; the coplanar congener was more cytotoxic than the nonplanar congener. The study elaborates threshold levels for these chemicals and suggests that the cytotoxicity mechanisms by which PCB congeners act on HELF cells depend on their planarity and chemical structures. Furthermore, the study will be important for developing antidotes to the adverse effects and risk assessment practices for PCBs. © 2016 Wiley Periodicals, Inc. Environ Toxicol 32: 1183-1190, 2017.


Assuntos
Poluentes Ambientais/toxicidade , Fibroblastos/fisiologia , Bifenilos Policlorados/toxicidade , Apoptose , Ciclo Celular/efeitos dos fármacos , Linhagem Celular , Proliferação de Células/efeitos dos fármacos , Fibroblastos/efeitos dos fármacos , Humanos , Pulmão/citologia , Conformação Molecular , Relação Estrutura-Atividade
19.
Ecotoxicol Environ Saf ; 127: 135-43, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-26827277

RESUMO

The aim of this study was to evaluate the effect of traffic related polycyclic aromatic hydrocarbons (PAHs) on blood parameters of subjects, including traffic police officers (TP), drivers (DR) and control subjects (CN) with presumably different levels of exposure. We quantified the urinary 1-hydroxypyrene (1-OHPyr), α-naphthol and ß-naphthol (α- and ß-naph) as biomarkers of exposure to PAHs in relation with biomarkers of effect (Hb, MCV, PCV, PLT, RBCs), biomarkers of inflammation/infection (CRP, WBCs), oxidative stress (SOD) and oxidative DNA damage i.e. 8-hydroxy-2-deoxyguanosine (8-OHdG). Results showed that mean 1-OHPyr, α-naph and ß-naph concentrations were significantly higher in TPs (0.98, 1.55, and 1.9µmolmol-Cr(-1), respectively, p<0.05) than CNs (0.7, 0.6; 0.67µmolmol-Cr(-1), respectively, P<0.05). Furthermore, WBC and CRP were found in higher concentrations in TPs than CNs (7.04×10(3)µL(-1) and 0.95mgL(-1) vs. 5.1×10(3)µL(-1) and 0.54mgL(-1), respectively). The urinary 8-OHdG level, a biomarker of oxidative DNA damage, was higher in TPs than both CN and DR subjects (48ngmg-Cr(-1), 24ngmg-Cr(-1) and 33ngmg-Cr(-1), respectively). Self-reported health assessment indicates that, on the basis of daily time spent in the middle of heavy traffic, TPs and DRs more frequently suffered from adverse head and respiratory symptoms. The PCA analysis evidenced the impact of traffic pollution on exposure biomarkers and DNA damage. The study suggests that traffic pollution may be associated with important health risk, in particular on the respiratory system, not only for workers exposed to traffic exhausts but also for general public. Finally, vehicular air pollution in the city of Rawalpindi should be a high-priority concern for the Pakistan Government that needs to be addressed.


Assuntos
Poluição do Ar/efeitos adversos , Condução de Veículo , Exposição Ocupacional/efeitos adversos , Polícia , Emissões de Veículos/toxicidade , 8-Hidroxi-2'-Desoxiguanosina , Adulto , Poluição do Ar/análise , Antioxidantes/metabolismo , Biomarcadores/metabolismo , Proteína C-Reativa/análise , Estudos de Casos e Controles , Cidades , Dano ao DNA/fisiologia , Desoxiguanosina/análogos & derivados , Desoxiguanosina/urina , Humanos , Masculino , Pessoa de Meia-Idade , Estresse Oxidativo/fisiologia , Paquistão , Hidrocarbonetos Policíclicos Aromáticos/análise , Superóxido Dismutase/metabolismo , Emissões de Veículos/análise , Adulto Jovem
20.
Ecotoxicol Environ Saf ; 125: 9-15, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26650420

RESUMO

This study was conducted with the aim of analyzing persistent organic pollutants i.e., PCBs, PBDEs, DPs and OCPs for sediment samples collected from Mehmood Booti Drain, Lahore, Pakistan that receives higher pollution loads from adjacent waste dumping site. Levels of ∑PCBs, ∑PBDEs, ∑DPs and ∑OCPs ranged between 5.9-62, 0.36-1.32, n.d.-0.02 and 0.96-18.07ngg(-1,) respectively. These levels were found to be comparable with other studies of local or global origin. Composition, spatial distribution and source profile indicated that Mehmood Booti waste dumping site was the major input source for sedimentary POPs pollution. The highest POPs deposition flux and mass inventory was attributed to PCBs and OCPs. Deposition flux indicated the input of 6E(-04), 5E(-05), 9E(-07) and 4E(-0)(4)t/yr of PCBs, PBDEs, DPs and OCPs into the Mehmood Booti Drain sediments which ultimately discharge into the River Ravi. Mass inventories suggested 1E(-02), 3E(-04), 7E(-06) and 3E(-03) metric tons PCBs, PBDEs, DPs and OCPs burden, respectively in the Mehmood Booti Drain sediments.


Assuntos
Monitoramento Ambiental , Sedimentos Geológicos/química , Compostos Orgânicos/análise , Instalações de Eliminação de Resíduos , Resíduos/efeitos adversos , Éteres Difenil Halogenados/análise , Substâncias Perigosas/análise , Hidrocarbonetos Clorados/análise , Paquistão , Praguicidas/análise , Bifenilos Policlorados/análise , Poluentes Químicos da Água/análise
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