Human Hazard Research Articles

Assessment of potential hazard for humans when eating apples and grapes treated with insecticide based on spiromesifen

Chemical plant protection pro­ducts account for at least 3 % of all biosphere pollutants and are the most studied pollutants on our planet. A very significant potential risk to public health is the consumption of foodstuffs contaminated with residual quantities of pesticide compounds. The aim of the work was to assess the potential hazard to humans when eating apples and grapes treated with an insecticide based on spiromesifen. A stepwise study was used: the content of spiromesifen in apples and grapes was calculated; the risk to humans was assessed (comparing the values of the permissible daily intake of the compound with food products with the maximum possible daily intake); the integral hazard index of pesticide-contaminated products consumption was calculated and assessed. The results obtained for the determination of residual amounts of spiromesifen in apples and grapes made it possible to substantiate the value of its maximum allowable value – 0.02 mg/kg; apple and grape juices – 0.01 mg/kg. It was found that the actual intake of spiromesifen with apples and grapes can be 0.0065 mg, and this does not exceed 0.5% of the permissible daily intake, or 0.7% of the estimated permissible amount of spiromesifen that can be consumed with food. According to the value of the integral index of hazard in contaminated food consumption (6 points) spiromesifen belongs to class 3 – moderately dangerous to humans. It has been established that substantiated standards for spiromesifen make it possible to ensure the safety of consumption of grapes and apples grown with the Oberon Rapid 240 SC application, as well as the use of other pesticide formulations based on this substance on other crops.

Reproductive and metabolic toxic effects of polystyrene microplastics in adult female Wistar rats: a mechanistic study

Microplastics, such as polystyrene microplastics (PS-MPs), have become an emerging environmental hazard for animals and humans. Long-term exposure to PS-MPs has led to neurotoxicity, reproductive dysfunction, and carcinogenesis. The goal of this study was to evaluate the effect of sub-chronic exposure of PS-MPs on metabolic and reproductive functions in female rats. The PS-MPs were prepared by cryogenic technique. The PS-MPs were given orally to female Wistar rats for 45days at 2.5, 5, and 10mg/kg/day. The average PS-MPs' size diameter was 876nm. The PS-MPs administration resulted in a significant decrease in the activity of superoxide dismutase and catalase in the liver and ovary. The effect of PS-MPs on reduced glutathione and lipid peroxidation in the liver and ovarian tissues of rats was statistically insignificant. The PS-MP exposure exhibited an increase in the levels of triglycerides, total cholesterol, and low-density lipoprotein and decrease in high-density lipoprotein. The PS-MPs caused glucose intolerance and increase in insulin. Moreover, the PS-MP exposure increased follicle stimulating hormone, estradiol, and testosterone. Serum level of interleukin-6 and nuclear factor kappa B (NF-κB) was elevated in animals treated with PS-MPs. The PS-MP exposed rats showed normal ovarian histology, but activated hepatic stellate cells and liver fibrosis. It is concluded that the sub-chronic exposure to PS-MPs resulted in metabolic and endocrine disruption in female rats through oxidative damage, hormonal imbalance, and chronic inflammation.

Graphene-Related Nanomaterials for Biomedical Applications

This paper builds on the context and recent progress on the control, reproducibility, and limitations of using graphene and graphene-related materials (GRMs) in biomedical applications. The review describes the human hazard assessment of GRMs in in vitro and in vivo studies, highlights the composition-structure-activity relationships that cause toxicity for these substances, and identifies the key parameters that determine the activation of their biological effects. GRMs are designed to offer the advantage of facilitating unique biomedical applications that impact different techniques in medicine, especially in neuroscience. Due to the increasing utilization of GRMs, there is a need to comprehensively assess the potential impact of these materials on human health. Various outcomes associated with GRMs, including biocompatibility, biodegradability, beneficial effects on cell proliferation, differentiation rates, apoptosis, necrosis, autophagy, oxidative stress, physical destruction, DNA damage, and inflammatory responses, have led to an increasing interest in these regenerative nanostructured materials. Considering the existence of graphene-related nanomaterials with different physicochemical properties, the materials are expected to exhibit unique modes of interactions with biomolecules, cells, and tissues depending on their size, chemical composition, and hydrophil-to-hydrophobe ratio. Understanding such interactions is crucial from two perspectives, namely, from the perspectives of their toxicity and biological uses. The main aim of this study is to assess and tune the diverse properties that must be considered when planning biomedical applications. These properties include flexibility, transparency, surface chemistry (hydrophil-hydrophobe ratio), thermoelectrical conductibility, loading and release capacity, and biocompatibility.

Hazard characterisation for significant mycotoxins in food.

This review updates the current status of activities related to hazard characterisation for mycotoxins, with special reference to regulatory work accomplished within the European Union. Because the relevant information on these topics is widely scattered in the scientific literature, this review intends to provide a condensed overview on the most pertinent aspects. Human health risk assessment is a procedure to estimate the nature and potential for harmful effects of mycotoxins on human health due to exposure to them via contaminated food. This assessment involves hazard identification, hazard characterisation, exposure assessment, and risk characterisation. Mycotoxins covered in this review are aflatoxins, ochratoxin A, cyclopiazonic acid, citrinin, trichothecenes (deoxynivalenol, nivalenol, T-2, and HT-2 toxins), fumonisins, zearalenone, patulin, and ergot alkaloids. For mycotoxins with clear genotoxic/carcinogenic properties, the focus is on the margin of exposure approach. One of its goals is to document predictive characterisation of the human hazard, based on studies in animals using conditions of low exposure. For the other, non-genotoxic toxins, individual 'no adverse effect levels' have been established, but structural analogues or modified forms may still complicate assessment. During the process of hazard characterisation, each identified effect is assessed for human relevance. The estimation of a 'safe dose' is the hazard characterisation endpoint. The final aim of all of these activities is to establish a system, which is able to minimise and control the risk for the consumer from mycotoxins in food. Ongoing research on mycotoxins constantly comes up with new findings, which may have to be implemented into this system.

Sand lizards (Lacerta agilis) decrease nymphal infection prevalence for tick‐borne pathogens Borrelia burgdorferi sensu lato and Anaplasma phagocytophilum in a coastal dune ecosystem

Abstract Understanding which factors determine tick‐borne disease hazard can contribute to effective disease control. In Europe, the hazard of the pathogens Borrelia burgdorferi s.l. and Anaplasma phagocytophilum is determined by local tick densities (mainly Ixodes ricinus) and the reservoir competence of the host species community. Sand lizards (Lacerta agilis) are common hosts for larvae and nymphs of I. ricinus and non‐competent reservoirs for both pathogens. Consequently, high relative abundance of L. agilis is hypothesized to be associated with lower infection prevalence in nymphs. Here, we aimed to test whether this effectively occurs in natural settings. We sampled different habitat types within a heterogenous dune landscape at the Dutch coast and estimated (1) L. agilis densities, (2) host community competence, (3) the density and infection prevalence of questing I. ricinus ticks and (4) the number and infection prevalence of ticks feeding on L. agilis. Captured L. agilis had high tick burdens and contributed substantially to feeding I. ricinus larvae in their natural habitat. B. burgdorferi s.l. and A. phagocytophilum were virtually absent from feeding larvae and nymphs. The nymphal infection prevalence of both pathogens in questing ticks was lower in habitat types where L. agilis was more abundant. Hence, L. agilis strongly reduced community competence. The density of questing nymphs was higher in habitat types with denser vegetation and also varied more between habitat types than infection prevalence. As a result, nymphal density had a stronger effect on the density of infected ticks than did nymphal infection prevalence. Synthesis and applications. Coastal dune habitats favourable for L. agilis have lower densities of questing nymphs and a lower human infection hazard. These results might be applicable to similar ecosystems where L. agilis is present. From a public health perspective, this underlines the importance of preserving early successional habitat, as encroaching shrubs are associated with higher tick‐borne disease hazard, and vegetation removal might be a solution to reduce hazard in coastal dunes. The high degree of spatial heterogeneity in the abundance of tick‐borne pathogens also poses opportunities to manage recreational activities to limit human exposure to tick‐borne diseases.

Why Islamic Economics ? The Difference Between The Conventional System And The Islamic Economic System

The presence of an economic system is a real part of the effort to answer the economic problem of what, haw, for whom. Every economic system has different ways and ways of solving these problems. This research aims to answer the main problem, why does it have to be Islamic economics? With the liberal research approach, these problems are discussed starting with data collection based on secondary data in the form of research articles and books related to the main focus of the research. Further data were analyzed using content analysis and comparative descriptive analysis methods. The results of this study indicate that the main reason why an Islamic economic system is needed is that Islamic economics is evident from various historical records starting from the beginning of the Prophet Muhammad. Until now the Islamic economic system is clearly different in answering the economic problems of what, haw, and for whom. The Islamic economic system rests on the principle of values that enable human moral hazard to be minimized by upholding the values of monotheism, justice and balance. While the conventional economic system, capitalism and socialism recorded various negative defects starting from the 1929 crisis, the Subprime Mortgage crisis, the dissolution of the Soviet NEP. The results of this study have implications for strengthening the importance of carrying out economic activities that are based on justice and a balance in life.

Wildfires as a Source of Potentially Toxic Elements (PTEs) in Soil: A Case Study from Campania Region (Italy)

The worldwide increase in fire events has attracted global attention, as potentially toxic elements (PTEs) have been widely recognised within the produced ash. Ash is transported, dispersed by wind, and deposited into the soil and surficial waters even far from fires. Considering that their composition can be enriched in PTEs, they represent a potential hazard for humans and other animals exposed to airborne particles and, afterwards, to resuspended matter, even at a considerable distance from the source. This study aimed to assess the environmental impact of fire events that occurred during the 2017 summer season at two different sites in the Campania region (Southern Italy). One of the fires affected a waste disposal site west of Caserta, and one involved a forest on the slopes of Mt. Somma-Vesuvius, a few kilometres southeast of Naples, the regional capital. Changes to the PTE concentration in the topsoil in the surroundings of both sites, after the fire events, were investigated. Enrichment factors (EFs) of a selection of PTEs were determined by comparing geochemical data from two sampling campaigns, one completed before and one after the fire events. A combined application of multivariate statistics (based on robust principal component analysis; RPCA) and geospatial analysis was used to determine the materials affected by the fire on the slopes of Mt. Somma-Vesuvius, and roughly locate their place. Specifically, a statistically significant enrichment of Hg was identified in the topsoil of both study areas. In addition, in soil samples collected at Mt. Somma-Vesuvius, more PTEs showed significant changes in their concentration. For both areas, Hg enrichments were related to the deposition of ash proceeding from waste burning; furthermore, as regards the soil of the Vesuvian area, Cr and Cd enrichments were associated with the fallout of ash generated during biomass combustion, and the increase in Cu and Zn concentrations was linked to the burning of crops on cultivated lands. Apart from the specific results obtained, concerning the examined case studies, the methods applied can be seen as a reliable option to determine the compositional characteristics of materials burned during a fire event, even with the prospect of improving the eventual assessment process of the related environmental hazards.

Designing illuminated maps of the number of lecturers in the city of Mosul using geographic information systems

Increased urbanization has led to an unthought doubling of the number of schools in the city, resulting in the selection of school sites that lack most standards such as environmental and health conditions, or their distance from natural and human hazards, and given the great potential of GIS to help find the most appropriate solutions and make the best decisions, particularly with regard to the processing and analysis of large and diverse spatial information, the current research aims to use GIS to assess the current status of school sites. At all primary and middle levels And preparatory, according to a set of natural, human and social standards. Gis is also used to document the current locations of schools and distribute them to residential neighbourhoods in the city to produce digital illuminated maps of the sites and pattern of the distribution of schools that are up-to-date, and the research to achieve this has relied on the data available to the Nineveh Education Directorate, as well as the field survey to locate schools with good accuracy using GPS and updating available data. The research found that there was a concentration in the distribution of schools that were sovereign in a concentrated or clustered pattern, some random in some, and regular in others, in general that might not reflect a similar distribution situation among all neighbourhoods in the city

Risk assessment of individuals exposed to urban floods

Risk assessment of individuals in urban flooding events requires quantitative criteria of human instabilities and hazard identifications. The existing guidelines might not be representative of some inundation situations in urban settings without considering the risks associated with human behaviors. Current guidelines may be under or over-estimated to be applied during a natural urban flooding disaster. This work proposes a hybrid model by coupling an efficient hydrodynamic model with a physics-based model to quantify individuals’ instabilities in urban flood events, both children and adults, based on the flow regimes and human physical characteristics. The model accounts for human behavior and the failure mechanism caused by physical instabilities of toppling, sliding, and drowning. The hazard degree is identified in terms of flow velocity and water depth in floodwaters. The hydrodynamic model is calibrated in a densely urbanized area in the city of the UK and the instabilities threshold curves for adults and children are validated using existing measurements in the literature. Applications of extreme precipitation events that occurred in Wuhan city of China showed that adults are relatively safe in most of the study sites with a low hazard except in the areas where the flood water depth exceeds the low limit of hazard criteria. However, the distribution of flood hazard degrees for children is significantly increased compared to that for adults. Furthermore, hazardous zones were observed in the vicinity of critical facilities such as the government house, supermarket, hospital, metro station, and primary school, consistent with the deep flood depth distribution. Overall, this work develops a hybrid model for risk assessment of individuals exposed to urban floods and the hazard criteria that could be implemented in urban flood risk management for sustainable cities.

The transmittable through stinging microbiota differs between honeybees and wasps: a potentially greater microbial risk of the wasp sting for humans

The present research investigated whether accidental contact through stinging with honeybees, wasps, and hornets could represent a microbial hazard for humans. It has been previously suggested that such contact may transmit pathogens causing infections that could even be fatal for some susceptible individuals. Stinging simulation experiments were performed in the lab with live insects collected from the environment in Lemnos Island (north-eastern Greece), while different selective agar media targeting some clinically important bacteria (i.e., Staphylococcus aureus, Streptococcus pyogenes, Enterococcus faecalis/faecium, and Pseudomonas aeruginosa) were used as substrates for microbial recovery and identification. Results revealed none of the target pathogenic bacterial species in the honeybee samples, with bacilli, staphylococci, and micrococci dominating their surveyed microbiota. However, most of the suspect colonies isolated from wasps and hornets belonged to important hygienic indicators (i.e., enterococci, Proteus mirabilis, and coliforms), implying possible contact of these insects with fecal origin materials. To sum up, the microbiota that may be transmitted to humans through stinging appears to differ between honeybees and wasps/hornets, while the isolation from the latter samples of some other important opportunistic pathogens, such as Enterobacter spp. and Klebsiella spp., also known for multidrug resistance, could be an additional reason of concern.

A NEW APPROACH FOR MAPPING LAND USE / LAND COVER USING GOOGLE EARTH ENGINE: A COMPARISON OF COMPOSITION IMAGES

Abstract. In view of the increase in human activities, climate change and related hazards, land use and land cover (LULC) mapping is becoming a fundamental part of the process of any development or hazard prevention project. From this perspective, we propose a new approach for mapping LULC using Machine learning algorithms by comparing the result of five composition methods based on Google Earth Engine in the city of Tetouan - Morocco. To achieve this goal, considering the Sentinel S2 L2 imageries as a source data , five datasets were derived to make the classification generating by aggregating functions (median , mean , max , min and mode). Then based on the very high resolution (VHR) satellite images provided by Google Earth comes the next step that involves selecting samples that are divided into five classes (barren land, water surface, vegetation, forest, and urban areas), which will be further split into two parts: 70% as a training data -used to feed the machine learning algorithms (support vector machine (SVM), random forest (RF) and classification and regression trees (CART))- and 30% as a testing data for evaluating the models using accuracy assessments. The results for all datasets indicate that the SVM algorithm has the highest accuracy and its performance is better than the other algorithms (RF and CART). The average overall accuracy of SVM , RF , and CART was 87.99% , 87.81% and 84.72% , respectively. Furthermore, for each algorithm, the comparison between the results of the different composites indicates that the use of the mean composite is the most suitable for LULC mapping. Finally, GEE has proven to be an effective and rapid method for LULC mapping, especially with the use of compositional imagery that can assist decision makers in future planning or risk prevention.

Human factors hazard modeling in the systems modeling language

AbstractAn ongoing challenge within the field of Systems Engineering is the application of a right‐scoped and consistent approach to modeling human functions and risks within a system lifecycle. Humans interacting with a system can be modeled along a continuum from passive agents with not well‐defined interfaces with the system operations, to essential personnel who are responsible for dynamic interactions that ensure the safety and correct function of the system. This paper seeks to contribute to the integration of a model of human function, response, and reliability into the systems engineering of a complicated system through translation of a Human Factors Hazard Model (HFHM) into the Systems Modeling Language (SysML). The HFHM is constructed as a sequential event tree model of human response to triggering events, where each event's likelihood of failure is modeled by a set of fault trees predicting human failure probabilistically using Human Error Probabilities (HEP). Implementation of this model in SysML is demonstrated through a set of stereotyped structural, behavioral, and parametric diagrams. Integration of the HFHM within SysML demonstrates the benefits of human factors modeling and integration into Model‐Based Systems Engineering (MBSE) processes illustrating executability, reusability, and traceability.

The State of the Art and Challenges of In Vitro Methods for Human Hazard Assessment of Nanomaterials in the Context of Safe-by-Design.

The Safe-by-Design (SbD) concept aims to facilitate the development of safer materials/products, safer production, and safer use and end-of-life by performing timely SbD interventions to reduce hazard, exposure, or both. Early hazard screening is a crucial first step in this process. In this review, for the first time, commonly used in vitro assays are evaluated for their suitability for SbD hazard testing of nanomaterials (NMs). The goal of SbD hazard testing is identifying hazard warnings in the early stages of innovation. For this purpose, assays should be simple, cost-effective, predictive, robust, and compatible. For several toxicological endpoints, there are indications that commonly used in vitro assays are able to predict hazard warnings. In addition to the evaluation of assays, this review provides insights into the effects of the choice of cell type, exposure and dispersion protocol, and the (in)accurate determination of dose delivered to cells on predictivity. Furthermore, compatibility of assays with challenging advanced materials and NMs released from nano-enabled products (NEPs) during the lifecycle is assessed, as these aspects are crucial for SbD hazard testing. To conclude, hazard screening of NMs is complex and joint efforts between innovators, scientists, and regulators are needed to further improve SbD hazard testing.

Ultra-Responses of Asphodelus tenuifolius L. (Wild Onion) and Convolvulus arvensis L. (Field Bindweed) against Shoot Extract of Trianthema portulacastrum L. (Horse Purslane).

Weed infestation is a prime challenge coupled with lowering crop production owing to their competition with crop plants for available resources such as nutrients, water, space, moisture, and sunlight. Among weed control methods, the implementation of synthetic herbicides offers an instant solution for getting rid of weeds; however, they are a direct source of potential hazards for humans and generate resistance against synthetic weedicides, making them less effective. Allelopathy is something that happens in nature that can be used as a weed control method that increases crop yield and decreases dependency on synthetic chemicals. The mode of action of some phytochemicals corresponds to synthetic herbicides. Due to this feature, allelochemicals are used as bio-herbicides in weed management and prove more environmentally friendly than synthetic weedicides. The present investigation aims to assess the ultra-responses of A. tenuifolius and C. arvensis, while growing them in a pot experiment. Various levels of shoot extract (L2, L3, and L4) of T. portulacastrum along with the L1 (distilled water) and L5 (synthetic herbicide) were applied to the weeds. Results indicated that aqueous extracts of shoot of T. portulacastrum significantly (p ≤ 0.05) affect all the measured traits of weeds and their effects were concentration specific. All morphological parameters were suppressed due to biotic stress with an increase in free amino acids and calcium ions along with a decline in metaxylem cell area and cortical thickness in the root, while the vascular bundle area increased. The shoot extract intrusive with metabolisms corresponded with the synthetic herbicide. It is concluded that Trianthema shoot extract has a powerful phytotoxic impact on weeds (A. tenuifolius and C. arvensis) and can be used in bio-herbicide production.

Different Sensitivity of Advanced Bronchial and Alveolar Mono- and Coculture Models for Hazard Assessment of Nanomaterials.

For the next-generation risk assessment (NGRA) of chemicals and nanomaterials, new approach methodologies (NAMs) are needed for hazard assessment in compliance with the 3R's to reduce, replace and refine animal experiments. This study aimed to establish and characterize an advanced respiratory model consisting of human epithelial bronchial BEAS-2B cells cultivated at the air-liquid interface (ALI), both as monocultures and in cocultures with human endothelial EA.hy926 cells. The performance of the bronchial models was compared to a commonly used alveolar model consisting of A549 in monoculture and in coculture with EA.hy926 cells. The cells were exposed at the ALI to nanosilver (NM-300K) in the VITROCELL® Cloud. After 24 h, cellular viability (alamarBlue assay), inflammatory response (enzyme-linked immunosorbent assay), DNA damage (enzyme-modified comet assay), and chromosomal damage (cytokinesis-block micronucleus assay) were measured. Cytotoxicity and genotoxicity induced by NM-300K were dependent on both the cell types and model, where BEAS-2B in monocultures had the highest sensitivity in terms of cell viability and DNA strand breaks. This study indicates that the four ALI lung models have different sensitivities to NM-300K exposure and brings important knowledge for the further development of advanced 3D respiratory in vitro models for the most reliable human hazard assessment based on NAMs.

Approaches to mixture risk assessment of PFASs in the European population based on human hazard and biomonitoring data.

Per- and polyfluoroalkyl substances (PFASs) are a highly persistent, mobile, and bioaccumulative class of chemicals, of which emissions into the environment result in long-lasting contamination with high probability for causing adverse effects to human health and the environment. Within the European Biomonitoring Initiative HBM4EU, samples and data were collected in a harmonized way from human biomonitoring (HBM) studies in Europe to derive current exposure data across a geographic spread. We performed mixture risk assessments based on recent internal exposure data of PFASs in European teenagers generated in the HBM4EU Aligned Studies (dataset with N=1957, sampling years 2014-2021). Mixture risk assessments were performed based on three hazard-based approaches: the Hazard Index (HI) approach, the sum value approach as used by the European Food Safety Authority (EFSA) and the Relative Potency Factor (RPF) approach. The HI approach resulted in the highest risk estimates, followed by the RPF approach and the sum value approach. The assessments indicate that PFAS exposure may result in a health risk in a considerable fraction of individuals in the HBM4EU teenager study sample, thereby confirming the conclusion drawn in the recent EFSA scientific opinion. This study underlines that HBM data are of added value in assessing the health risks of aggregate and cumulative exposure to PFASs, as such data are able to reflect exposure from different sources and via different routes.

The Role of Modern Techniques in Preservation of Archaeological Sites

Abstract Archaeological sites have always suffered from loss and degradation due to many human and natural hazards. In recent decades, interest in preserving archaeological sites has increased dramatically. Many modern techniques have emerged from the different disciplines that can be used in preservation works, and a large number of the techniques and their capability made it difficult for decision-makers and specialists to determine the appropriate technique that gives the best results in preserving the archaeological site. The research aims to identify the project needed to preserve the archaeological site and then choose the appropriate technique for it, based on the opinions of experts using the analytic hierarchy process (AHP) method, which helps decision-makers and specialists to choose the most appropriate technology. The archaeological site of Babylon was chosen as a case study. As a result of applying the AHP method, the priority weights of preservation stages for the archaeological site of Babylon were determined as follows: (diagnosis and monitoring 30.8 %), (intervention 21.2 %), and (tourism and media 16.6 %), while the appropriate technique was determined as follows: (infrared thermography 29.4 %), (maintenance 49.3 %), and (augmented reality 38.7 %).

Knowledge mapping and current trends of global research on snoRNA in the field of cancer.

Cancer is a major health hazard for humans. Recent studies have indicated the involvement of small nucleolar RNAs (snoRNAs) in the occurrence and development of cancer and indicated its potential role as a diagnostic/prognostic marker and therapeutic target. The purpose of this study was to use the bibliometrics method to analyze the published literature on this subject. We collected articles pertaining to the field of snoRNA and cancer from the Web of Science Core Collection database. The data were analyzed to identify the research hotspots and frontiers. The number of articles in this field was low in the early period. Chu Liang and Montanaro Lorenzo were the most prolific authors on this subject, while Jiang and Feng were the most frequently cited authors. In China, three institutions published the most articles, namely Wuhan Univ, China Med Univ, and Guangxi Med Univ. The journal with the highest number of articles on this subject was Oncotarget. The country with the most published articles was China. Analysis of keywords and burst words indicated that early studies mainly focused on molecular mechanisms. Available evidence suggests the involvement of snoRNAs in the molecular mechanism of cancer development and their potential role as a diagnostic and prognostic biomarker.

Are Particulate Pollutants Emitted by Open-Burning of Agricultural Plastic Waste (Greenhouse LDPE Film) Harmful?

Background and objective: Agricultural plastic waste (APW), which includes various types of plastics and greenhouse film, accounts for the largest volume of annual average incineration of plastic (Korea Environment Corporation, 2021). Open-burning incineration of such APW emits metallic particulate pollutants, the human hazard of which is widely known. As such, the systematic management of incinerable APW is required. Furthermore, basic physicochemical research on particulate pollutants (PPs) is needed for related policy decision-making.Methods: The U.S. EPA particulate test method (Method 5G) was applied to set up the experimental infrastructure for an open-air incineration simulation. Scanning electron microscopes with SEM-EDS and XRF were used for a chemical species analysis of the generated particulate matter (PM). Low-density polyethylene (LDPE), used as a greenhouse material and collected by the Dangjin plastic collection office of the Korea Environment Corporation, was used as samples and subjected to incineration test three times.Results: Chemical speciation by an XRF analysis showed that the major chemical components of LDPE before incineration, listed in order of their content, were Fe (26.87%, SD = 20.67) > Si (25.91%, SD = 11.29) > Al (16.43%, SD = 7.23), which was changed to Si (44.51%, SD = 0.25) > Zn (16.53%, SD = 0.03) > Ba (15.73%, SD = 0.05) after incineration. An SEM-EDS analysis found the PM emitted as rock-like shapes and cotton-like shapes. Regarding the weight ratio, the rock-shaped particles contained less C (8.94 wt%, SD = 1.90) and more Al (11.77 wt%, SD = 3.08) and Fe (9.58 wt%, SD = 7.14), whereas the cotton-shaped particles contained more C (29.44 wt%, SD = 3.97), less Al (2.34 wt%, SD = 0.19), and an untraceable amount of Fe (ND).Conclusion: This study found that PPs emitted through the incineration of APW such as LDPE can be classified into rock-like shapes and cotton-like shapes, which is related to the difference in weight ratio of non-metals (C), transition metals (Fe), and other metals (Al) in unit particulate matter.

Feasibility study for estimating optimal substrate parameters for sustainable green roof in Sri Lanka

In twenty-first century buildings, green roof systems are envisioned as great solution for improving Environmental sustainability in urban ecosystems and it helps to mitigate various health hazards for humans due to climatic pollution. This study determines the feasibility of using five domestic organic wastes, including sawdust, wood bark, biochar, coir, and compost, as sustainable substrates for green roofs as compared to classical Sri Lankan base medium (fertiliser + potting mix) in terms of physicochemical and biological parameters associated with growing mediums. Comprehensive methodologies were devised to determine the thermal conductivity and electric conductivity of growing mediums. According to preliminary experimental results, the most suitable composition for green roof substrates comprised 60% organic waste and 40% base medium. Sawdust growing medium exhibited the highest moisture content and minimum density magnitudes. Biochar substrate was the best performing medium with the highest drought resistance and vegetation growth. The wood bark substrate had the highest thermal resistance. Growing mediums based on compost, sawdust, and coir produced the best results in terms of nitrate, phosphate, pH, and electric conductivity (EC) existence. This study provided a standard set of comprehensive comparison methodologies utilising physicochemical and biological properties required for substrate characterization. The findings of this research work have strong potential in the future to be used in selecting the most suitable lightweight growing medium for a green roof based on stakeholder requirements.