Actual Hazard Research Articles

Spatial Mapping for Multi-Hazard Land Management in Sparsely Vegetated Watersheds Using Machine Learning Algorithms

This study breaks new ground by developing a multi-hazard vulnerability map for the Tensift watershed and the Haouz plain in the Moroccan High Atlas area. The unique juxtaposition of flat and mountainous terrain in this area increases sensitivity to natural hazards, making it an ideal location for this research. Previous extreme events in this region have underscored the urgent need for proactive mitigation strategies, especially as these hazards increasingly intersect with human activities, including agriculture and infrastructure development. In this study six advanced machine learning (ML) models were used to comprehensively assess the combined probability of three significant natural hazards: flooding, gully erosion, and landslides. These models rely on causal factors derived from reputable sources, including geology, topography, meteorology, human activities, and hydrology. The research's rigorous validation process, which includes metrics such as specificity, precision, sensitivity, and accuracy, underlines the robust performance of all six models. The validation process involved comparing the model's predictions with actual hazard occurrences over a specific period. According to the outcomes in terms of the area under curve (AUC), the XGBoost model emerged as the most predictive, with remarkable AUC values of 93.41% for landslides, 91.07% for gully erosion and 93.78% for flooding. Based on the overall findings of this study, a multi-hazard risk map was created using the relationship between flood risk, gully erosion, and landslides in a geographic information system (GIS) architecture. The innovative approach presented in this work, which combined ML algorithms with geographical data, demonstrates the power of these tools in sustainable land management and the protection of communities and their assets in the Moroccan High Atlas and regions with similar topographical, geological, and meteorological conditions that are vulnerable to the aforementioned risks.

Improving efficiency and accuracy of levee hazard detection with deep learning

This paper presents a model framework based on a deep learning algorithm using Faster R-CNN to improve the accuracy and efficiency of detecting long-distance levee hazards. The proposed method aims to assist technicians in identifying hazards in resistivity inversion profiles, thereby reducing the manual workload and extracting valuable information from a large volume of data using deep learning techniques. To this end, we constructed a dataset of levee hazards using inversion images of electrical resistivity imaging data obtained from numerical simulations, indoor experiments, and actual levee hazards. Subsequently, we utilized image augmentation techniques to expand the dataset and enhance the model's performance, resulting in a total of 2000 labeled hazard images. The network was then trained from scratch by setting the hyperparameters. the trained weight parameters and network architecture were saved for future use. The model's performance was evaluated using standard evaluation metrics, including precision, recall, F1 score, and average precision (AP). The proposed model demonstrated robustness and adaptability, achieving high precision and accuracy with an AP value of up to 100%. Furthermore, we validated the method using three cases, and the results indicated its superiority over traditional manual identification-based or outlier analysis detection of levee hazards in practical scenarios. This study emphasizes the significant advantages of deep learning techniques over the traditional methods, including improved accuracy, automation, speed, and scalability. It suggests that intelligent detection based on deep learning can accurately identify and locate hazards in levees.

A hybrid deep semantic mining method considering fuzzy expressions for the automatic recognition of construction safety hazard information

Safety hazards are a key consideration in construction management. The efficient recognition of safety hazard information can help managers formulate safety hazard management measures and improve the efficiency of construction safety management. However, construction site safety hazard data are stored in semistructured and unstructured text formats, which cannot be directly converted into understandable and usable information. Moreover, safety hazard text contains many fuzzy expressions, thereby increasing the difficulty of text semantic analysis; thus, how to accurately mine safety hazard information from complex and diverse text data is an urgent problem that must be solved. In consideration of this problem, we propose a bidirectional long short-term memory (BiLSTM) method with a fuzzy word vector and self-attention mechanism (FSABiLSTM) to automatically recognize safety hazard information. This method adopts TextRank and Word2vec to calculate the fuzzy word vector and process fuzzy expressions in safety hazard text. The safety hazard text semantic features are deeply extracted based on BiLSTM and a fuzzy word vector, and the extracted semantic features are analyzed via a self-attention mechanism. Actual construction safety hazard text is used to verify the reliability and applicability of the method, and the results indicate that the accuracy of this method, which outperforms existing machine learning methods, is 91.70%. In addition, the FSABiLSTM method can be used to automatically evaluate the risk degree of safety hazards; this use is beneficial to managing and controlling safety hazards. Concerning safety hazard text data, this study provides a new deep mining approach that can enhance safety management efficiency.

Health Physics Aspects Associated with Magnetic Confinement Fusion Power Facilities

Bevelacqua Resources, 7531 Flint Crossing Circle SE, Owens Cross Roads, AL 35763 USA bevelresou@aol.com Health physics aspects associated with magnetic confinement fusion are addressed. These aspects are investigated within the context of the operation of the International Thermonuclear Experimental Reactor currently called ITER. ITER has health physics elements in common with existing fission facilities as well as unique fusion related features. Fusion facility neutron radiation is similar to that encountered in a low energy accelerator. The tritium hazard has radiation protection issues in common with the Canadian Deuterium reactor. Completion of the final ITER design, its performance characteristics, component lifetimes, and maintenance requirements will determine the actual health physics hazards. Numerous open issues are required to complete the design of ITER and resolution of these issues will affect the design as well as the health physics implications for occupationally exposed workers. Key Words: Fusion Power Facility, ITER, Magnetic Confinement, Radiological Characteristics

Hazards and Risks Investigation of the Fit Out Project of RMM Construc-tion: Basis for Creation of an Occupational Construction and Health and Safety Program

The existence of hazards and risks in businesses is inevitable, specifically, in the construction industry. The research is qualitative by nature which aimed the identification and investigation of the actual hazards and risks in the workplace as experienced by the select construction workers as main participants in the research. A total of eleven (11) constructions workers were utilized in the research and selected by way of purposive sampling. During the focus discussions, participants are divided into three groups. Among others, results revealed the following construction-related hazards: Scattered Broken Tiles, Unstable Scaffolding, Scattered Nails, Insufficient Lightning, Exposed Extension Wire and Chiselling and Grinding, No Insulation and Physical Transport of Heavy materials. The research further investigated the level of risks in the identified hazard using the probability and severity matrix. At average, the identified risks obtained a high level of probability while severity at average is to medium or moderate only. Occupational Construction and Health and Safety Program was developed based on the results of this research.

Queer vulnerability and disaster situations

<abstract> <p>The appropriateness of branding certain disaster events as a natural disaster continues to be academically debated, given that few disasters are solely the result of uncontrollable forces of nature, and are instead anthropogenic in their creation, or exacerbated by the relationship humans have with actual and potential hazards. Therefore, this socially constructed nature of disasters also makes groups that are marginalized within society, such as queer people, more vulnerable to these disasters. Utilizing a Bourdieusian framework, the field of disaster preparedness, management, and recovery is examined for queer vulnerability, which is deconstructed here as a product of global and local cultures, in their distribution of economic, social, cultural, and symbolic capital away from queer people. The concepts of habitus and subsidiary concepts of ethos and doxa are deployed to understand the ingrained ways of doing and being that perpetuate discrimination against queer individuals through said inequitable distributions of capital. It is argued that the field is privileged for heteronormative lives, thus leading to heteronormative assumptions and actions that further marginalize queer experiences before, during, and after disasters during disasters. In light of this, we call for a more social justice informed approach to disaster risk reduction and relief, in which heteronormativity is consciously decentered to ensure all groups are kept safe from disasters, which can arguably never be natural.</p> </abstract>

Impacts and risks of “realistic” global warming projections for the 21st century

The IPCC AR6 assessment of the impacts and risks associated with projected climate changes for the 21st century is both alarming and ambiguous. According to computer projections, global surface temperature may warm from 1.3 °C to 8.0 °C by 2100, depending on the global climate model (GCM) and the shared socioeconomic pathway (SSP) scenario used for the simulations. Actual climate-change hazards are estimated to be high and very high if the global surface temperature rises, respectively, more than 2.0 °C and 3.0 °C above pre-industrial levels. Recent studies, however, showed that a substantial number of CMIP6 GCMs run “too hot” because they appear to be too sensitive to radiative forcing, and that the high/extreme emission scenarios SSP3-7.0 and SSP5-8.5 are to be rejected because judged to be unlikely and highly unlikely, respectively. Yet, the IPCC AR6 mostly focused on such alarmistic scenarios for risk assessments. This paper examines the impacts and risks of “realistic” climate change projections for the 21st century generated by assessing the theoretical models and integrating them with the existing empirical knowledge on global warming and the various natural cycles of climate change that have been recorded by a variety of scientists and historians. This is achieved by combining the SSP2-4.5 scenario (which is the most likely SSP according to the current policies reported by the International Energy Agency) and empirically optimized climate modeling. According to recent research, the GCM macro-ensemble that best hindcast the global surface warming observed from 1980 to 1990 to 2012–2022 should be made up of models that are characterized by a low equilibrium climate sensitivity (ECS) (1.5 °C < ECS ≤ 3.0 °C), in contrast to the IPCC AR6 likely and very likely ECS ranges at 2.5–4.0 °C and 2.0–5.0 °C, respectively. I show that the low-ECS macro-GCM with the SSP2-4.5 scenario projects a global surface temperature warming of 1.68–3.09 °C by 2080–2100 instead of 1.98–3.82 °C obtained with the GCMs with ECS in the 2.5–4.0 °C range. However, if the global surface temperature records are affected by significant non-climatic warm biases — as suggested by satellite-based lower troposphere temperature records and current studies on urban heat island effects — the same climate simulations should be scaled down by about 30%, resulting in a warming of about 1.18–2.16 °C by 2080–2100. Furthermore, similar moderate warming estimates (1.15–2.52 °C) are also projected by alternative empirically derived models that aim to recreate the decadal-to-millennial natural climatic oscillations, which the GCMs do not reproduce. The proposed methodologies aim to simulate hypothetical models supposed to optimally hindcast the actual available data. The obtained climate projections show that the expected global surface warming for the 21st-century will likely be mild, that is, no more than 2.5–3.0 °C and, on average, likely below the 2.0 °C threshold. This should allow for the mitigation and management of the most dangerous climate-change related hazards through appropriate low-cost adaptation policies. In conclusion, enforcing expensive decarbonization and net-zero emission scenarios, such as SSP1-2.6, is not required because the Paris Agreement temperature target of keeping global warming < 2 °C throughout the 21st century should be compatible also with moderate and pragmatic shared socioeconomic pathways such as the SSP2-4.5.

Work intensity and work modification amid implementation of anti-epidemic activities

Introduction. Assessment of work intensity (WI) is challenged by several methodical complications. It may involve certain underestimation of an actual hazard category of working conditions and fails to consider work modification. &#x0D; Materials and methods. The study relies on using analytical, sociological, and statistical methods. To test the selected approach, a sample was created from workers with mostly mental work (n=137, 77% females). Their average age was 43.9±8.0 years; average work experience was 14.5±3.7 years. &#x0D; Results. In this article, we suggest certain approaches to assessing WI. They include self-assessment of a factor using a specifically designed questionnaire; they clarify indicators that describe WI; when assessing working conditions, they rely on matrices of interrelated indicators. This procedure makes it possible to estimate levels of individual components and create an integral WI profile as well as identify contributions made by various intensity types to its overall structure. When testing the procedure, we established workers with mostly mental work to tend to have harmful working conditions as per WI factor (the hazard category 3.1 in 24.8% of the cases; 3.2, 56.9% of the cases; and the hazard category 3.3 in 17.5% of the cases). Mental (28.6±6.1%) and sensory (24.0±7.0%) loads are limiting components. Amid implementation of anti-epidemic activities, work regime was established as the most sensitive WI component (its contribution grew from 11.1±6.0 to 16.0±5.7%, p&lt;0.05). Working conditions moved to a higher hazard category for 35.8% workers.&#x0D; Limitations. Assessment of working conditions uses threshold values introduced more than 30 years ago and can be adjusted for the existing employment conditions. The testing was accomplished on a rather small sample, which was biased as per gender and included workers with different occupations and positions.&#x0D; Conclusion. The suggested approaches offer wider opportunities to assess working conditions as per WI with respect to some occupations. This may substantiate a list of indicators that should be regulated by the existing sanitary legislation. Investigation of possible modification of factors during the pandemic makes it possible to describe eligibility of anti-epidemic activities without any deterioration of working conditions.

ENVIRONMENTAL RISKS FOR PUBLIC HEALTH AS A SIGNIFICANT CRITERION FOR CREATING FUNCTIONAL ZONES IN A CITY WITHIN URBAN DEVELOPMENT

Background. This study focuses on a vital issue concerning the necessity to consider public health when making decisions on urban development.&#x0D; Purpose. Test approaches to using available data on environmental public health risks when creating functional zones in a large industrial center.&#x0D; Materials and Methods. Aerogenic health risks associated with ambient air pollution were assessed by calculating dispersion of emissions from 2500 industrial sources and 4000 traffic network sections as well as by using environmental monitoring data.&#x0D; Results. We established that 1889 land spots of 3619 functional zones with standardized air quality were fully or partially located in areas with unacceptable public health risks. These land spots included 905 residential areas and 984 spots with recreational potential.&#x0D; Conclusion. Obviously, an inconsistency between actual health hazards for city population and a functional purpose of a zone requires immediate action. Either a functional purpose should be changed, or certain air protection activities should be implemented to make ambient air quality conform to the existing standards and to guarantee acceptable health risks levels. Either option requires environmental and economic substantiation. Any decision on changes in a specific situation in each specific functional zone should be made separately considering hazards, their sources and reasons for their occurrence. These decisions should rely on economic estimates and technical capabilities necessary for implementation of planned activities. People’s life and health should always remain the top priority. The study describes an algorithm for considering environmental factors when functional zones are created within urban development.

Mineralogical, Petrological and Geochemical Characterisation of Chrysotile, Amosite and Crocidolite Asbestos Mine Waste from Southern Africa in Context of Risk Assessment and Rehabilitation

Derelict asbestos mine sites in South Africa pose a considerable risk to human, environmental and socio-economic health. Comprehensive mineralogical and geochemical datasets for the existing hazardous geological materials still exposed in Southern African derelict asbestos mines remain largely non-existent, as very little published and up-to-date literature is available. In this study, three representative types of asbestos mineral fibres from derelict asbestos mines in Southern Africa, namely chrysotile from Havelock mine, amosite from Penge mine and crocidolite from Prieska mine, are characterized mineralogically and geochemically to critically evaluate actual hazards in rural and asbestos-fibre-contaminated regions. The samples were examined using polarising light microscopy, X-ray fluorescence (major and trace elemental analysis), X-ray diffraction (including Rietveld refinement), specific surface area analysis and bio-durability testing. Data are discussed in view of their potential toxicities on both human health and the environment in the context of developing countries. Finally, information on the mineralogical and geochemical status of asbestos mine waste and its importance as baseline data for rehabilitation considerations is also evaluated.

Rapid characterization of combustible particle breakage via dry dispersion laser diffraction

Dust explosion hazards can be analyzed by various explosion parameters, which are known to depend on the particle size distribution of combustible dust. Literature has evidenced the dispersion system in laboratory apparatus (e.g., 20-L chamber) breaks the original dust into smaller sizes. Such unexpected particle breakage can lead to misleading explosion results which may exaggerate the actual hazards. This study develops a novel solution to identify combustible particle breakage by exploiting dry dispersion laser diffraction technology. Nine samples were dispersed under different levels of energy in a particle size analyzer. Serious particle breakage is confirmed if the tested particle size decreases significantly with increasing dispersion pressure. Eight particle size parameters were plotted to derive quantitative pressure titration curves. A larger average slope in percentage decreases of D10, D50, and D3,2 represents a higher particle breakage tendency. The characterization results are well correlated to previous breakage classification in the 20-L chamber.

Assessing different measures of fire risk for Cultural World Heritage Sites

This study aims to assess whether two publicly available sources of fire threats to 346 Cultural World Heritage Sites across Europe substitute or complement each other. By doing so, a novel measure based on information from the UNESCO periodic report II is created and benchmarked against the European forest fire information system (EFFIS) index. The UNESCO periodic report shows that forest fires are perceived as an actual or foreseeable hazard by 40% of the management of Cultural World Heritage Sites in Europe. When the EFFIS index is linked to the UNESCO World Heritage database, it occurs that 48% of these sites are at high risk of fire, 31% at medium risk and 21% at low risk. Results based on Probit and Fractional Probit estimations reveal that the perceived fire risk relates to several site characteristics as well as location. The regressions using the EFFIS index as dependent variable show indifference to site characteristics even if location is of importance. Estimations give that the perceived fire risk is highest for sites in the East and the North of Europe, while the results for the EFFIS index lead to a dominant risk in the South. A 10° increase in latitude (corresponding to the distances between Vienna and Stockholm or Athens and Vienna) leads to a considerable decrease in the proportion of high fire risk by 28 percentage points (with a sample mean of 48%). Thus, the two measures of fire risks complement rather than substitute each other. Latitude is of no importance for the site managers, although the EFFIS gives this aspect a heavy weight, with low or zero risks in locations at higher latitudes (Iceland, Ireland, Latvia, and Norway) and larger risks in Southern Europe (Cyprus, Malta, Portugal, Albania, Spain, and Greece). In addition, the perception of (wild)-fire threat is significantly lower for cities.

Correlation Between Early Trends of a Prognostic Biomarker and Overall Survival in Non-Small-Cell Lung Cancer Clinical Trials.

Overall survival (OS) is the primary end point in phase III oncology trials. Given low success rates, surrogate end points, such as progression-free survival or objective response rate, are used in early go/no-go decision making. Here, we investigate whether early trends of OS prognostic biomarkers, such as the ROPRO and DeepROPRO, can also be used for this purpose. Using real-world data, we emulated a series of 12 advanced non-small-cell lung cancer (aNSCLC) clinical trials, originally conducted by six different sponsors and evaluated four different mechanisms, in a total of 19,920 individuals. We evaluated early trends (until 6 months) of the OS biomarker alongside early OS within the joint model (JM) framework. Study-level estimates of early OS and ROPRO trends were correlated against the actual final OS hazard ratios (HRs). We observed a strong correlation between the JM estimates and final OS HR at 3 months (adjusted = 0.88) and at 6 months (adjusted = 0.85). In the leave-one-out analysis, there was a low overall prediction error of the OS HR at both 3 months (root-mean-square error [RMSE] = 0.11) and 6 months (RMSE = 0.12). In addition, at 3 months, the absolute prediction error of the OS HR was lower than 0.05 for three trials. We describe a pipeline to predict trial OS HRs using emulated aNSCLC studies and their early OS and OS biomarker trends. The method has the potential to accelerate and improve decision making in drug development.

Preventing kidney transplant failure by screening for antibodies against human leucocyte antigens followed by optimised immunosuppression: OuTSMART RCT

Design Investigator-led, prospective, open-labelled marker-based strategy (hybrid) randomised trial. Background Allografts in 3% of kidney transplant patients fail annually. Development of antibodies against human leucocyte antigens is a validated predictive biomarker of allograft failure. Under immunosuppression is recognised to contribute, but whether increasing immunosuppression can prevent allograft failure in human leucocyte antigen Ab+ patients is unclear. Participants Renal transplant recipients &gt; 1 year post-transplantation attending 13 United Kingdom transplant clinics, without specific exclusion criteria. Interventions Regular screening for human leucocyte antigen antibodies followed, in positive patients by interview and tailored optimisation of immunosuppression to tacrolimus, mycophenolate mofetil and prednisolone. Objective To determine if optimisation of immunosuppression in human leucocyte antigen Ab+ patients can cost-effectively prevent kidney allograft failure. Outcome Time to graft failure after 43 months follow-up in patients receiving the intervention, compared to controls, managed by standard of care. Costs and quality-adjusted life-years were used in the cost-effectiveness analysis. Randomisation and blinding Random allocation (1 : 1) to unblinded biomarker-led care or double-blinded standard of care stratified by human leucocyte antigen antibodies status (positive/negative) and in positives, presence of donor-specific antibodies (human leucocyte antigen antibodies against donor human leucocyte antigen) or not (human leucocyte antigen antibodies against non-donor human leucocyte antigen), baseline immunosuppression and transplant centre. Biomaker-led care human leucocyte antigen Ab+ patients received intervention. Human leucocyte antigen Ab-negative patients were screened every 8 months. Recruitment Began September 2013 and for 37 months. The primary endpoint, scheduled for June 2020, was moved to March 2020 because of COVID-19. Numbers randomised From 5519 screened, 2037 were randomised (1028 biomaker-led care, 1009 to standard of care) including 198 with human leucocyte antigen antibodies against donor human leucocyte antigen (106 biomaker-led care, 92 standard of care) and 818 with human leucocyte antigens antibodies against non-donor human leucocyte antigen (427 biomaker-led care, 391 standard of care). Numbers analysed Two patients were randomised in error so 2035 were included in the intention-to-treat analysis. Outcome The trial had 80% power to detect a hazard ratio of 0.49 in biomarker-led care DSA+ group, &gt; 90% power to detect hazard ratio of 0.35 in biomarker-led care non-DSA+ group (with 5% type 1 error). Actual hazard ratios for graft failure in these biomarker-led care groups were 1.54 (95% CI: 0.72 to 3.30) and 0.97 (0.54 to 1.74), respectively. There was 90% power to demonstrate non-inferiority of overall biomarker-led care group with assumed hazard ratio of 1.4: This was not demonstrated as the upper confidence limit for graft failure exceeded 1.4: (1.02, 95% CI 0.72 to 1.44). The hazard ratio for biopsy-proven rejection in the overall biomarker-led care group was 0.5 [95% CI: 0.27 to 0.94: p = 0.03]. The screening approach was not cost-effective in terms of cost per quality-adjusted life-year. Harms No significant differences in other secondary endpoints or adverse events. Limitations Tailored interventions meant optimisation was not possible in some patients. We did not study pathology on protocol transplant biopsies in DSA+ patients. Conclusions No evidence that optimised immunosuppression in human leucocyte antigen Ab+ patients delays renal transplant failure. Informing patients of their human leucocyte antigen antibodies status appears to reduce graft rejection. Future work We need a better understanding of the pathophysiology of transplant failure to allow rational development of effective therapies. Trial registration This trial is registered as EudraCT (2012-004308-36) and ISRCTN (46157828). Funding This project was funded by the National Institute for Health and Care Research (NIHR) Efficacy and Mechanism Evaluation programme (11/100/34) and will be published in full in Efficacy and Mechanism Evaluation; Vol. 10, No. 5. See the NIHR Journals Library website for further project information.

Assessing genuine flammability hazard of halogenated species for their safe processing and use: Case studies

It is recognized that the combustion of halogenated substances (gas and liquids) may present specific features compared to traditional hydrocarbons. As a matter of facts, the standardized flammability characterization methods referenced by the various regulations (transport, labeling, etc.) do not necessarily take the specific features of these substances into account. Subsequently, this may lead to an underestimation of the risk associated with their use (physical hazard such as explosion). Through two case studies of interest, one concerning a fluorinated liquid, the other focusing on a fluorinated gas, this work reveals technical difficulties that may arise in appraising actual flammability hazards of halogenated hydrocarbons, due to their combustion specific behavior, when applying existing flammability methods without appropriate expert judgement. In the case of the liquid ethoxy-nonafluorobutane (Novec 7200™) this work highlights that this substance can be erroneously considered non-flammable due a clear pitfall of flash point methods, whilst its genuine flammability can be revealed otherwise. Regarding gaseous halogenated species, we show that operating conditions shall be carefully selected to reveal the genuine flammability behavior of such substances. Indeed, this is not necessarily correctly identified in all possible flammability hazard rating standard methods. In this study, the application of European standards allows to confirm that R1234ze(E) is flammable at temperatures below 30 °C, at atmospheric pressure and at a humidity of 50%RH.

Impact of Site-Response Characterization on Probabilistic Seismic Hazard in the Po Plain (Italy)

ABSTRACT We present a probabilistic seismic hazard analysis (PSHA) for the entire Po Plain sedimentary basin (Italy)—one of the widest Quaternary alluvial basins of Europe, to evaluate the impact of site-response characterization on hazard estimates. A large-scale application of approach 3 of the U.S. Nuclear Regulatory Commission (NRC) to include seismic amplification in the hazard is presented. Both 1D amplification related to stratigraphic conditions and 3D amplification due to basin effects are considered with the associated uncertainties, and their impact on the hazard is analyzed through a sensitivity analysis. Whereas 3D basin effects are considered through the application of an empirical, spatial invariant correction term, 1D amplification was estimated throughout the study area by means of dynamic (equivalent linear) ground-response analysis. To separate aleatory variabilities and epistemic uncertainties related to site response, a partially nonergodic approach is used. The results provide a finer picture of the actual seismic hazard, highlighting those areas where the ground motion is affected by amplification effects due to local or regional geological features. We found that, for a return period of 475 yr, neglecting basin effects produces a 30% underestimation of the seismic hazard in the long-period (&amp;gt;1 s) range. Moreover, with reference to the hazard model adopted, such effects are responsible for most of the epistemic uncertainty (up to 80%) in the results. Therefore, such effects deserve special attention in future research related to PSHA in the Po Plain sedimentary basin.

Insights into the weathering behavior of pyrite in alkaline soil through electrochemical characterizations: Actual hazards or potentially benefits?

Pyrite is the most common metal sulfide mineral in the crust and readily weathers under natural circumstances to release H+ to acidify surrounding groundwater and soil, resulting in heavy metal ions in the surrounding environment (e.g., meadow and saline soils). Meadow and saline soils are two common, widely distributed alkaline soils and can affect pyrite weathering. Currently, the weathering behaviors of pyrite in saline and meadow soil solutions have not been systematically studied. Electrochemistry coupled with surface analysis methods were employed to study pyrite weathering behaviors in simulated saline and meadow soil solutions in this work. Experimental results suggest that saline soil and higher temperatures increase pyrite weathering rates due to the lower resistance and greater capacitance. Surface reactions and diffusion control the weathering kinetics, and the activation energies for the simulated meadow and saline soil solutions are 27.1 and 15.8 kJ mol−1, respectively. In-depth investigations reveal that pyrite is initially oxidized to Fe(OH)3 and S0, and Fe(OH)3 further transforms into goethite γ-FeOOH and hematite α-Fe2O3, while S0 ultimately converts into sulfate. When these iron compounds enter alkaline soils, the alkalinity of soil changes, and iron (hydr)oxides effectively reduce the bioavailability of heavy metals and benefit alkaline soils. Meanwhile, weathering of natural pyrite ores containing toxic elements (such as Cr, As, and Cd) makes these elements bioavailable and potentially degrades the surrounding environment.

A New Insight into the Stability of Precariously Balanced Rocks

Large granitic boulders resting on steep slopes represent considerable safety hazards that largely depend on the location of the contact surface characterized by the impression d, denoting the parallel distance between the contact surface and the original rock surface. On the other hand, this impression reflecting the often convex nature of the contact between boulders and resting platforms, cannot be measured precisely, so Factors of Safety (FoS) computed with this input may have significant uncertainties. Using geometric 3D analysis, here, we present the concept of computing FoS as a function of the impression d, admitting a much more reliable estimate of the actual hazards. Beyond introducing the FoS functions, we also identify all failure modes, some of which have not yet been investigated. We compute the FoS functions for the boulder Pena do Equilibrio, located in Spain. Our computations for FoS against sliding match all earlier results. However, we also compute FoS against toppling and against torsion and show that the latter may be critical. Since our methods are general, this suggests that torsion phenomena, which have been scarcely studied so far, may be relevant to analyze the stability of other natural rock boulders.

Non-Lethal Dose-Response Models Replace Lethal Bioassays for Predicting the Hazard of Para-Aminopropiophenone to Australian Wildlife.

Para-aminopropiophenone (PAPP) is a potent methaemoglobin (MetHb) forming agent used for the lethal control of exotic carnivores and mustelids. To assess the sensitivity of Australian wildlife to PAPP we developed an in vivo assay that did not use death as an endpoint. Sub-lethal dose-response data were modelled to predict PAPP doses required to achieve an endpoint set at 80% MetHb (MetHb80). The comparative sensitivity of non-target mammals referenced to this endpoint was found to be highly variable, with southern brown bandicoots (Isoodon obesulus) the most sensitive species (MetHb80 = 6.3 mg kg-1) and bush rats (Rattus fuscipes) the most tolerant (MetHb80 = 1035 mg kg-1). Published LD50 estimates were highly correlated with PAPP doses modelled to achieve the MetHb80 endpoint (r2 = 0.99, p < 0.001). Most dose-response data for native mammals were collected in the field or in semi-natural enclosures, permitting PAPP and placebo dosed animals to be fitted with tracking transmitters and transponders and released at their point of capture. A protracted morbidity and mortality was observed only in Australian ravens (Corvus coronoides). The combination of sub-lethal dose-response assay and survival data collected in the field provided more relevant information about the actual hazard of pest control agents to non-target wildlife species than laboratory-based lethal-dose bioassays. We discuss the need to replace lethal-dose data with biologically meaningful insights able to define a continuum of toxicological hazards that better serve the needs of conservation and veterinary scientists and wildlife managers.

Combination of Multidimensional Instrumental Analysis and the Ames Test for the Toxicological Evaluation of Mineral Oil Aromatic Hydrocarbons.

Mineral oil aromatic hydrocarbons (MOAHs) include mutagenic and carcinogenic substances and are considered a potential health risk. Current methods address the total MOAH content but cannot address the actual toxicological hazard of individual components. This work presents a combined methodology closing those gaps: high-performance liquid chromatography (HPLC) coupled to gas chromatography with flame ionization detection was used to determine the MOAH content. To characterize present substance classes, comprehensive two-dimensional gas chromatography with time-of-flight mass spectrometry was applied. Preparative HPLC separated MOAHs into subgroups, which were tested with a miniaturized Ames test evaluating DNA reactivity of isolated fractions. Combining these methods allowed a correlation between present subgroups and DNA reactivity. The developed approach was applied to a mineral oil and distinguished between not DNA-reactive mono- and diaromatics and DNA-reactive tri- and polyaromatics, providing a proof of concept. Hereinafter, it will be applied to diverse sample matrices including mineral oils, food, and food contact materials.