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Background: With rapid industrial development, heavy metal contamination has become a major public health and ecological concern worldwide. Although knowledge about metal pollution in European water resources is increasing, monitoring data and assessments in developing countries are rare. In order to protect human health and aquatic ecosystems, it is necessary to investigate heavy metal content and its consequences to human health and ecology. Accordingly, we collected 200 water samples from different water resources including groundwater, canals, river and drains, and investigated metal contamination and its implications for human and ecological health. This is the first comprehensive study in the region that considered all the water resources for metal contamination and associated human health and ecological risks together. Results: Here we show that the water resources of Lahore (Pakistan) are highly contaminated with metals, posing human and ecological health risks. Approximately 26% of the groundwater samples are unsuitable for drinking and carry the risk of cancer. Regarding dermal health risks, groundwater, canal, river, and drain water respectively showed 40%, 74%, 80%, and 90% of samples exceeding the threshold limit of the health risk index (HRI > 1). Regarding ecological risks, almost all the water samples exceeded the chronic and acute threshold limits for algae, fish, and crustaceans. Only 42% of groundwater samples were below the acute threshold limits. In the case of pollution index, 72%, 56%, and 100% of samples collected from canals, river Ravi, and drains were highly contaminated. Conclusions: In conclusion, this comprehensive study shows high metal pollution in water resources and elucidates that human health and aquatic ecosystems are at high risk. Therefore, urgent and comprehensive measures are imperative to mitigate the escalating risks to human health and ecosystems. [ABSTRACT FROM AUTHOR]

The exposure variation of arsenic from different ground and surface water sources has remained unpredictable which may cause severe human health problems. The current study is, therefore, designed to analyze the spatial variability of arsenic contamination in shallow aquifer and assess the potential human health risks. For this purpose, a total of 55 groundwater, 10 drain water, 4 river water, and 6 sediment samples were collected along zero to 5 km stretch of the River Ravi, Lahore. All water samples were tested for As, pH, and total dissolved solids (TDS), whereas sediments were only tested for As. Health risk models were used to predict cancer and non-cancer risk in adults and children. Among water samples, highest median (minimum–maximum) concentrations (µg/L) of As were recorded 53.32 (1.98–1555) in groundwater, followed by 53.04 (1.58–351.5) in drain water, and 4.80 (2.13–8.67) in river water, respectively, whereas As concentration (mg/kg) in river sediments was 6.03 (5.56–13.92). Variation of As in groundwater was non-significant (P > 0.05) among every 1-km stretch from the Ravi River. However, maximum median concentrations (µg/L) of 60.18 and 60.08 were recorded between 2–3 and 0–1 km from River Ravi, respectively, reflecting possible mixing of river water with shallow aquifers. A very high cancer and non-cancer risk (HI > 1.0 × 10−4) through groundwater As exposure was predicted for both children and adults. The current study concluded that prevalence of As above WHO prescribed limits in shallow aquifer along the urban stretch of the River Ravi is posing serious health risk to the exposed population. [ABSTRACT FROM AUTHOR]

This study investigated the seasonal and temporal variations in the extent and source of physiochemical and toxic trace elements in the Lakhodair landfill site of Lahore, Pakistan. For this purpose, systematic composite samples were collected every month, consecutively for 1 year, and analyzed for different physiochemical parameters and trace elements. The results of TDS, TSS, COD, NH3-N, BOD5, sulfate, sulfides, phenolic compounds, and oil and grease were higher than the national environmental quality standard (NEQs). The concentrations of trace elements, especially Mn (1.7 mg/L) and Cd (0.05 mg/L), were above the MPL, while Fe (14 mg/L), Ni (1.6 mg/L), and Zn (6.7 mg/L) were also found higher than the NEQs in some samples. In Lakhodair leachates, the TDS, COD, NH3-N, BOD5, sulfides, and Cl− have high concentration coefficient (i.e., CC 3 to > 6), which falls in the category of considerable to high contamination and risk level, while the remaining parameters were in the category of low to moderate contamination (CC 1 to ≤ 3) and moderate risk. The lower BOD5/COD ratio (< 0.1) in spring and autumn seasons represents the active methanogenesis and anaerobic activities in the Lakhodair landfill site. The anaerobic and methanogenesis activities enhance the redox reaction as a result of CO2 emission, which increases the pH, TDS, COD, Cl−, BOD5, NH3-N, sulfides, and phenolic compounds in the leachate site. However, the lower concentrations of some trace elements in leachate may be because of an anaerobic process that may immobilize the trace elements. It is presumed that the trace elements in the Lakhodair landfill may be in a metastable state, which is difficult to leach out. It is hereby recommended that leachate produced in the Lakhodair landfill site should be handled carefully to limit the environmental and health implications. [ABSTRACT FROM AUTHOR]

Microplastics (MPs) pollution is an emerging global environmental concern. Considering the high fraction of time people spend indoors, the human population can be directly exposed to this contamination through indoor dust. This preliminary study evaluates MPs' abundance and human health risk assessment in the deposited indoor dust. A total of forty dust samples (n = 20) were collected from homes in two different cities (Pakistan) in steel mesh pouches using the vacuum cleaner. The identification and quantification of MPs were conducted with a stereo microscope, whereas the qualitative assessment was performed with Fourier transform infrared spectroscopy (FTIR). The US EPA parameters to calculate the human health risk assessment were used to determine MPs' risk per-day/month/year. Overall, microfibers were the dominant category, followed by microfilms, micro-fragments, and nurdles. The chemical categorization of MPs was revealed as polyester, polyethylene, copolymers of polypropylene, and polyurethane. In Lahore, an average abundance of 241.45 (items/m2) MPs were observed compared to Sahiwal, with 162.1 (items/m2). More than 90% of the identified MPs were microfibers, with higher detection frequency and abundance in Lahore than Sahiwal. The human health risk assessment revealed high exposure risk because of indoor MPs. Moreover, toddlers were more vulnerable as compared to adults at both low and high exposure risk scenarios. There is an imminent need to conduct in-depth risk assessment focusing on the respirable fraction of MPs. [ABSTRACT FROM AUTHOR]

Rapid urbanization and associated waste generation have become a mounting ecological concern for wildlife, especially avian communities. Research has primarily focused on investigating the impacts of human activities on marine birds with comparatively less focus on terrestrial species that live in far more anthropized environments and are at significant risk. Our study has explored the abundance and characteristics of anthropogenic litter in 70 nests of four generalist bird species: Bank Myna (Acridotheres ginginianus) , Common Myna (Acridotheres tristis), Black Kite (Milvus migrans) and House Crow (Corvus splendens) , within the city of Lahore (Pakistan) and its surroundings, by determining and following an urbanization gradient. The overall frequency of litter occurrence (FLO%) for all the sampled nests was 89%. Over 80% of the recorded litter items consisted of plastic materials, primarily dominated by sheet-like plastics. There was a strong association between fabric and Black Kite nests, and metal and House Crow nests. Litter incorporation increased across the gradient from rural to urban habitats. The highest FLO% was found in nests sampled from waste dumping sites and urban sites (95%–100%), where anthropogenic influence was more intense. The high level of litter incorporation is potentially indicative of a species' adaptive response to urbanization, associated with the decline in natural nesting material and availability of anthropogenic litter. These findings highlight the need for strengthening the existing global database for terrestrial litter and its effect on wildlife and devising policy actions for better waste management and conservation of natural ecosystem balance. [Display omitted] • The presence of litter in nests is indicative of surplus availability of anthropogenic waste in the surroundings. • The abundance of plastic sheets in cavity nests suggests its use as cushioning material. • High incorporation of fabric and metal in platform nests reflects its use as a structural material. • Frequency of anthropogenic litter incorporation increased along the urbanization gradient. • Nests in urban and waste dumping sites showed the highest variety of anthropogenic litter. [ABSTRACT FROM AUTHOR]

Decomposition of organic waste in dumping sites and landfills prompts the uncontrolled emission of greenhouse gases which enhances global warming and related issues. The present investigation estimated the total landfill gas, methane, carbon dioxide and non-methane organic compounds emissions from Mahmood Booti dumping site located at Lahore, Pakistan from 1996 to 2045. LandGEM 3.02 model was utilized to evaluate the gas emission with the volumetric methane 50%, production potential (170 m3/Mg), and methane generation rate (0.050/year). The findings demonstrated that organic and food wastes had the maximum quantity in the solid waste stream (63.46%). Methane measured from solid waste was 1.150E+03 (Mg/year) in 1997 in the first year after waste was accepted by landfill while the maximum methane generation rate happened from 2014 to 2018, i.e., from 4.049x104 to 4.654x104 Mg/year, respectively. The study finding highlighted that all gases emissions have an increasing/rising trend up to 2021 and then gradually their level will decrease because most of the organic fractions of solid waste would degrade with time. The findings of this study can be used to identify the impacts and contribution of MBODS in the global emission of greenhouse gases. The study concludes that proper management of landfill gas will not only decreases greenhouse gas emissions, diminishing adverse impacts on public health but can also be used as a sustainable energy source. [ABSTRACT FROM AUTHOR]

The demand for water escalated over the years and led to water shortage in many parts of the world. This situation further intensified due to water pollution. This research involves the analysis of groundwater from selected locations along River Ravi, the estimation of economic value of water for intended uses and mapping of threat zones regarding poor quality groundwater consumed by the people or the residents of the selected areas. Questionnaire survey was used as a tool for economic valuation and laboratory analysis was performed for quality testing. The quality of water was found to be average in terms of chemical and bacteriological parameters. Whereas physical parameters were found within acceptable limits. Total dissolved solids (TDS), Turbidity and Electrical conductivity (EC) results were found to be within the permissible limits given by World Health Organization (WHO). However, pH of the water samples of few areas violated the permissible limit of WHO (6.5–8.5). Among chemical parameters, nickle (0.07 mg/l) chromium (1.0 mg/l), cobalt (0.02 mg/l) and arsenic (10 ppb) exceeded their respective permissible limit. Contingent valuation method (CVM) was used for determining Willingness to pay (WTP) for drinking water quality which was found to be low (Rs. 3.848). This was due to the low-literacy level as residents were not aware of the consequences of the contaminated water. The economic value of water for irrigation purpose determined through Residual valuation method (RVM), was found to be 37.46 Wheat > 28.41 Sugarcane > 23.05 Rice. This implicates that wheat has the highest ratio for productivity and residual value as compared to rice and sugarcane. Farmers should be encouraged to grow more of wheat crops as compared to sugarcane and rice. Threat areas for deteriorated water quality were mapped for better understanding of general public regarding drinking water quality in their vicinity. [ABSTRACT FROM AUTHOR]

This preliminary investigation highlights the occurrence of organochlorine pesticides (OCPs) in the indoor environment of a megacity, Lahore, Pakistan using the dust ensnared by air‐conditioner filters. The Σ16OCPs concentration ranged from 7.53 to 1272.87 ng/g with the highest percent contribution by ΣDDT (dichlorodiphenyltrichloroethane; 87.21%) and aldrin (6.58%). The spatial variation of OCPs profile revealed relatively higher concentration from homes near to agricultural and abandoned DDT manufacturing sites. Calculated isomer ratios revealed historic sources of hexachlorocyclohexanes (HCHs) and the fresh input of technical DDT and chlordane by the dwellers. The air conditioner dust was helpful to better understand the health risk in the indoor environment. So far a high lifetime cancer risk (10−3) was predicted for toddlers via accidental ingestion, inhalation, and dermal exposure. Similarly, the non‐carcinogenic risk‐based hazard quotient was found to be high for toddlers (6.94) and within the permissible limit (<1) for adults. [ABSTRACT FROM AUTHOR]

The study objective is to predict the epidemiological impact of dengue fever arbovirosis in urban tropical areas of Pakistan. To do so, we used the GPS-based data of the Aedes larvae collected during 2014–2015 in Lahore. We developed a Geographically Weighted Logistic Regression (GWLR) model for Geospatially predicting larvae presence or absence in Lahore. Data on rainfall, temperature are included along with time series of the normalized difference vegetation index (NDVI) derived from Landsat imagery. We observed a high spatial variability of the GWLR parameter estimates of these variables in the study area. The GWLR model significantly ( R a 2 = 0.78) explained the presence or absence of Aedes larvae with temperature, rainfall and NDVI variables in South and Southeast of the study area. In the North and North-West, however, GWLR relationships were observed weak in highly populated areas. Interpolating GWLR coefficients generate more accurate maps of Aedes larvae presence or absence [ABSTRACT FROM AUTHOR]

Background: Occupational stress is a common concern among employees, particularly those working in tertiary care hospitals. In Pakistan, both medical and paramedical staffs face many stressors because of their high job demand, dealing with multiple patients, excessive duty hours, and strict rules and regulations. The objective of the study was to measure occupational stress among the tertiary care hospital employees of the Lahore District using different demographic and workplace determinants. Methods: It was a cross-sectional study. A total of 138 hospital employees recorded their responses, which included 71 medical staff/doctors and 67 paramedical staff members. Primary data was obtained through a detailed structured questionnaire based on the Likert scale with the stress level index ranging from 1-5. Results: In terms of the six staff designations, stress index from top to bottom was observed in house officers/internees (3.47), medical officers/postgraduate trainees (3.04), technicians (2.74), consultants/specialists (2.73), emergency/ward assistants (2.61) and nurses (2.46). Among all the employees, the most significant factors leading to stress bottom-down were justice/fairness (3.30), tasks and roles (3.14), management (3.03), environment/working conditions (3.01), decision-making autonomy (2.84), work schedule (2.62) and profession/job entitlement (1.63). Analysis of demographic characteristics showed that males (2.99) faced greater stress than females (2.64) and people of young age group (= 30 years) showed the highest stress value (3.01) than other age groups. It was observed that moderately experienced (5-10 years) employees were more prone to occupational stress (3.03) than other groups. Furthermore, the employees of public hospitals (3.13) bear more stress than those of private hospitals (2.67). On the basis of locality, the locals showed slightly higher stress values (2.89) as compared to non-locals (2.77). Conclusion: The current study showed that occupational stress is a prevalent problem in hospitals, particularly among house officers and postgraduate residents. Several useful steps can be undertaken to improve the health and safety of hospital employees like alleviating duty hours, working in shifts, focusing on a single task, and motivating the employees in decision-making. [ABSTRACT FROM AUTHOR]

Urban Heat Island (UHI) is related to the theory of higher atmosphere and surface temperature taking place in the city area as compared to the nearby rural areas. The study results explain the advantages of green spaces in urban areas. Landsat TM/OLI concept of 1998 and 2017 years was attained from USGS for this work. To find out the land-use and land cover pattern supervised classification, the maximum prospect process is adopted. A total of four classes were mapped for the study area which includes built-up, barren land, vegetation, and water bodies. Effective sensor brightness temperature has been acquired from spectral radiance by using Plank's reverse function. On the basis of surface emissivity, Normalize Difference Vegetation Index (NDVI) classes are used to find out the ultimate temperature of the land surface (LST). The maximum temperature was recorded in the built-up area and barren land of the city and minimum temperatures were noted in areas with a greater cover of vegetation. The presence of UHI temperature is obvious from the land surface temperature views. An increase of 2 °C in surface temperature is recorded in district Lahore during the last two decades. Rise of 2.2 °C and 2.4 °C surface temperature has taken place in Faisalabad and Multan Districts in the last 19 years, respectively. In the establishment of a correlation among the LST, built-up, and vegetation, there is a positive sign present in their relation. With the increase in the built-up area, LST does increase as well. Moreover, with the reduction in vegetation cover, the LST is also raised. The study has revealed that there is a need for proper planning for the durable management of urbanization. [ABSTRACT FROM AUTHOR]

Plastics are widely considered to be a major threat particularly in the urban areas owing to extensive use of plastic products. The current study is the first investigation to highlight the microplastics (MPs) pollution from the freshwater (Ravi River) located in the predominant urban center, i.e., Lahore, Pakistan. The concentration profile was quantified from surface water (n = 19) and sediments (n = 19) collected from different drains and canals of predominant freshwater resources in Lahore, Pakistan. The highest content of MPs was observed in the sullage carrier with mean concentration of 16,150 ± 80 MPs/m3 and 40,536 ± 202 MPs/m2 in the water and sediments respectively. The lowest level was detected in the link canals with mean concentration of 190 ± 141 MPs/m3 in the water and 683 ± 479 MPs/m2 in the sediments. The proportion of large size MPs (300 μm–5 mm) was maximum in the upstream section of Ravi river, whereas fine size MPs (50–150 μm) were dominant in the downstream section. In terms of shapes, the fragments were predominant with a relative abundance of 56.1% and 83.1% followed by fibers with a relative abundance of 38.6% and 11.8% in the water and sediments respectively. The chemical composition analysis showed that most of the fibers, fragments, and beads were polyethylene while the sheets were composed of polypropylene. Nevertheless, the foams isolated from the samples were composed of polystyrene. Within 24 h, about 2.4 ± 2.4 billion microplastic pieces were estimated to be transported from a single water channel into the river. The highest discharge of MPs was estimated from the sullage carrier with about 7 billion pieces/day. [ABSTRACT FROM AUTHOR]

In this study, we investigated metal- and metalloid-induced oxidative stress response in two aquatic (cattle egret (Bubulcus ibis) (n = 10), pond heron (Ardeola grayii) (n = 10)), as well as two terrestrial (spotted owlet (Athene brama) (n = 6) and bank myna (Acridotheres ginginianus) (n = 16)) bird species collected from the outskirts of Lahore city, Pakistan. For this purpose, glutathione (tGSH) and lipid peroxidation (thiobarbituric acid-reactive substances (TBARS)) levels and activities of antioxidant enzymes (superoxide dismutase (SOD); catalase (CAT)) were analyzed as biomarkers of oxidative stress against metal (Pb, Cd, Cu, Zn) and metalloid (As) concentrations in kidney liver and blood of birds. Our results depicted significant correlation for Pb, Cd, and As with oxidative stress biomarkers in birds. The levels of heavy metals and As and their corresponding effects on oxidative stress biomarkers were comparably higher in aquatic species (p ≤ 0.01) except for Pb and Zn. In comparison of species, SOD and tGSH activities were higher in bank myna and cattle egret, while CAT activity and TBARS concentrations were higher in pond heron and cattle egret, respectively. We deduced that tissues with higher accumulation of metal(loid)s such as liver and kidney were under a great risk to oxidative damage. The overall order of metal accumulation and subsequent oxidative damage among families followed the pattern as Strigidae ≥Ardieda ≥ Sturnidae with their respective trophic levels. Globally, metal- and As-induced oxidative stress is least emphasized in multiple tissues of birds that is needed to be addressed with focus on case-control studies using dose-response approach. [ABSTRACT FROM AUTHOR]

Increasing concentration of trace metals in the environment and their subsequent health effects in living organisms has become a major threat particularly in developing parts of the world. Therefore present study was designed to investigate the concentration of trace metals such as Pb, Cd, Cr and Cu in liver, pectoral muscle, pelvic muscle and blood of two terrestrial (Bank Myna; Acridotheres ginginianus and Jungle Babbler; Turdoides striata) and two aquatic (Grey Heron; Ardea cinerea and Cattle Egret; Bubulcus ibis) bird species collected from the premises of Lahore, Pakistan. The detection frequency of trace metals in collected samples were highest in Cd (100%) followed by Pb (83%), Cr (80%) and Cu (76.5%). Species revealed heterogeneous levels of metals in all organs. In general the mean concentration (µg/g) of trace metals in organs and blood of terrestrial species followed the pattern as Pb > Cu > Cr > Cd contrary to aquatic species in which the trend was Cu > Pb > Cr > Cd. Highest concentration of Pb (3.23 µg/g) was reported in pelvic muscle of jungle babbler, Cd (0.15 µg/g) in liver of bank myna, Cr (0.40 µg/g) in pelvic muscle of Cattle Egret and Cu (1.89 µg/g) in liver of Cattle Egret. Whereas lowest concentration of Pb (0µg/g) and Cd (0.09 µg/g) was reported in blood and pelvic muscle of Grey Heron respectively, Cr (0µg/g) in blood of Bank Myna, Grey Heron and Cattle Egret, Cu (0 µg/g) in blood of Grey Heron, Cattle Egret and Jungle Babbler. Concentration of metals varied significantly (P<0.05) among organs however, no significant difference (P>0.05) was observed among species except Cu(P<0.05). Further, no significant difference (P>0.05) of metals was observed between feeding guilds and habitat of the species. The increasing concentration of toxic trace metals in the birds reflects deteriorating environmental health as a result of greater metals exposure which must be reduced through proper legislation and strict implementation of laws. [ABSTRACT FROM AUTHOR]

Microplastics (MPs) are emerging pollutants with detrimental effects on aquatic organisms and human health. The massive generation of plastic waste on land leads to MPs pollution in the aquatic environment. Some reports highlight the abundance of MPs in Pakistan however, no detailed research has been documented about the presence of MPs in the riverine environment. In this regard, the present study highlights the spatial distribution of MPs in River Ravi during monsoon and post-monsoon seasons. The MPs in water and sediment samples were isolated through wet peroxide oxidation digestion, density separation, and filtration followed by microscopic quantification and Fourier Transform Infrared Spectroscopy (FTIR) analysis. The results showed that in water samples, the average concentrations of MPs in monsoon and post-monsoon seasons were 768 ± 869 MPs/m3 and 1324 ± 1925 MPs/m3, whereas, sediments depicted 5323 ± 3792 MPs/kg-dry weight and 2637 ± 2701 MPs/kg-dry weight, respectively. Similarly, fiber was the most abundant type of MPs, and Polypropylene (PP), Polyethylene (PE), Polyester (PES), and Polystyrene (PS) were the most dominant polymer types in both environmental matrices. In terms of their sources, urban sprawl, industrialization, improper solid waste management, and overuse of plastic products are positively correlated with MPs level in River Ravi. Moreover, this is the first study on the spatiotemporal distribution of MPs in River Ravi from Pakistan and indicates the high burden of MPs pollution. Consequently, it will provide scientific information to policymakers and river managers to deal effectively with plastic pollution. [Display omitted] • High abundance of MPs were present in water from downstream of Lahore. • Sediment exhibited maximum deposition of MPs at upstream of Barrages. • High number of MPs in water (Post monsoon) and in sediment (Monsoon). • Less MPs recorded from downstream of Barrages due to water diversion for irrigation. [ABSTRACT FROM AUTHOR]

Sustainable urban land-use development and management practices are imperative to ensure the quality of the living environment. Unplanned expansion and densification of the urban area tend to imbalance the ratio of impervious surface to green spaces, resulting in the Surface Urban Heat Island (SUHI) effect. Land Use Land Cover changes, anthropogenic activity, and a sustainable future environment are all intertwined. This study aims to analyze urban policies impacts by quantifying built-up land, green spaces and their associated SUHI effects in the Lahore district of Pakistan. We used a tri-temporal medium resolution remote sensing imagery (2003, 2010 and 2019) and a long-term low resolution (1 km) Land Surface Temperature (LST) time series (2001–2020) to evaluate the impacts of the LULC changes on SUHI. We found rapid urban development in the study area over the last two decades (2003 - 2019) that resulted in the losses (36%) and gains (16%) in urban vegetation at the Union Council (UC) level. Spatial patterns showed the inconsistent distribution of green spaces across the study area. Large green spaces exhibit 1 to 4 °C lower LST compared to their surrounding built-up land. The overall green spaces were reduced from 15215 ha in 2003 to 10528 ha in 2010 and a total loss of ~19% was recorded in agricultural land and open spaces during 2003–2019. Nonetheless, it showed a recovery during the last decade with a current extent of 12316 ha in 2019. This increase in green space areas is due to the rising awareness about the significance of urban green spaces and nationwide plantation drives programs which help to mitigate SUHI effect. On the other hand, transition zones under development phase consisting of sand/vacant and barren land exhibit a mean 3-4 °C higher LST while the old city areas, including the walled city, continuously exhibit 1-2 °C higher LST from the average LST of the district which triggered the SUHI pockets formation. These results of the study highlight the importance of devising effective policies to monitor unprecedented urban sprawl and the reduction in the cooling effect because of disappearing vegetation particularly in old city areas and transition zones. However, the effective implementation of the urban land use policies should be ensured through institutional strengthening, adequate resource allocation, efficient procedures, and continuous geospatial monitoring for a better living environment and to combat climate change. • Rapid urbanization, vegetation loss and anthropogenic heating are the main drivers of increasing surface temperature. • Loss and gain in green space areas ranges from − 36–16% at Union Council level. • Transition zones exhibit highest LST causing SUHI formation and long term warming study area's temperature. • Large green spaces exhibit 1 to 4 °C lower land surface temperature compared to surrounding built-up land. • Land use policies should be carefully re-examined at national and local level. [ABSTRACT FROM AUTHOR]

Chlorinated paraffins (CPs) are widely used in commercial products due to their stability and durability and are subsequently released in the environment posing serious health risks in human population. In this study, dust samples from indoor and outdoor settings of residential, commercial and industrial zones as well as from vehicles were collected from a metropolitan city, Lahore, Pakistan. A total of 83 dust samples were analyzed for short (SCCPs) and medium (MCCPs) chained CPs through quadrupole time of flight mass spectrometer in atmospheric pressure chemical ionization (APCI QToF-MS) mode. The median concentrations of ƩCPs (C10-17) in outdoor dust were higher than indoor dust in industries (0.97 vs 0.48 μg/g), and residential areas (0.70 vs 0.13 μg/g) while lower in commercial areas (0.28 vs 0.44 μg/g) reflecting their higher prevalence in industrial and residential zones. The vehicular dust had median ƩCPs of 0.16 μg/g which was similar to residential indoor dust. Overall, ƩSCCPs were dominant among all zones with C 10,12 and Cl 7-8 as abundant carbon and chlorine congeners in both indoor and outdoor dusts. No significant correlations were observed between indoor and outdoor dust for ƩSCCPs and ƩMCCPs indicating their varying exposure. Health hazard index and margin of exposure revealed that toddlers were at higher risk compared to adults as a results of CPs exposure from both indoor and outdoor environments. This is the first ever assessment of CPs in Pakistan reflecting higher prevalence of SCCPs than MCCPs in dust of local environment posing some serious health consequences hence needed intensive investigation and effective management. [Display omitted] • Higher concentrations of CPs were detected in outdoor compared to indoor dust. • Industrial and commercial zones reflect higher level of CPs than residential and vehicles. • SCCPs were more prevalent than MCCPs in indoor and outdoor dust samples. • C 10, 12, 14 and Cl 7-9 congeners dominated both in indoor and outdoor samples. • Toddlers are more vulnerable to CPs exposure hence associated health risks. [ABSTRACT FROM AUTHOR]

The municipal solid waste (MSW) is widely considered as a heterogeneous source of energy, with numerous characteristics varying depending on its geographical region or origin from where it is collected. The development of correlations for the prediction of the higher heating value (HHV) of MSW is a sustainable and cleaner way based on data of specific region from where MSW is obtained. In this research, a new approach reported for the development of correlations to predict the energy content of MSW accurately. The developed correlations lie within the all parameter affecting the HHV of MSW. The models presented can predict the HHV of MSW accurately (R2 > 0.8) compared to other models reported in the literature. However, model 13 developed on the basis of ultimate analysis demonstrated maximum accuracy (R2 = 0.919) among all 7 developed models. The aim of developing the prediction model for the HHV of different MSW samples was to reliably predict using proximate or ultimate analytical data to save experimentation costs and provide theoretical foundations for modelling MSW combustion, pyrolysis processes and thermal conversion for the energy security. Image 1 • Municipal solid waste (MSW) samples were collected and characterized from Lahore. • Higher heating value (HHV) of MSW samples were measured precisely. • Eureqa-Formulize software was employed to develop HHV prediction models. • The developed models are compared with the reported models. [ABSTRACT FROM AUTHOR]