Evaluation Of Public Health Risks Research Articles

Airborne metal nanoparticles released by azides detonation: determination and potential public exposure

Metal azides are highly energetic materials that release a large amount of gas upon detonation. They also release metal particles, generating an aerosol. The most common azide is sodium azide (NaN3), which is used nowadays in car airbags. If the decomposition is not complete, harmful azide particles might be inhaled. Heavy metal azides find application as a primary explosive (primer) in ammunition. Public health officials have raised concerns about heavy metal particles released during training in shooting ranges. We identify a lack of knowledge on airborne metal particles properties released from azide detonation and on the analytical methods applied to characterize them. As a case study, we detonated milligram amounts of silver azide, copper azide, and a mixture of them in a glove box. We then analyse the airborne particles with an ensemble analytical setup, able to measure real-time their particle size distribution and chemical composition. We detected spherical metal nanoparticles in the range of 2–500 nm. These findings and the developed analytical tools may allow identifying airborne nanoparticles the passenger compartments of vehicles after airbag activation as well as in indoor shooting ranges, contributing to the evaluation of public health risks.

Selective cascade activation of polycyclic aromatic hydrocarbons in human cells: Role of enzyme's intrinsic electric field

Polycyclic aromatic hydrocarbons (PAHs) are major environmental organic pollutants. Some metabolites of PAHs show greater toxicity to humans while the others do not. It is highly important to decipher PAHs' regioselective activation mechanism and identify the major metabolites to accurately evaluate their public health risk. Here, we have performed a thorough computational study of benzo[a]anthracene (BA) metabolized by P450 1A1 by employing molecular docking, molecular dynamics simulations, quantum chemical calculation, and quantum mechanics/molecular mechanics calculations. Our findings show that highly-reactive species such as 3,4-epoxide, 8,9-epoxide, 3,4-diol-1,2-epoxide, and 8,9-diol-10,11-epoxide were major metabolites, which can efficiently react with guanine and damage DNA with extremely low energy barrier, therefore, supports the regioselective metabolism of BA. The origin of this selective activation is mainly contributed to both the oxygen‑carbon distance and previously overlooked enzyme's intrinsic electric field. Consequently, based on the resolved activation selectivity of BA. We built a high-throughput strategy to efficiently predict the metabolites of other PAHs. The accuracy of the strategy is validated by studying 16 PAHs on the priority control list. Hopefully this will aid the accurate evaluation of public health risks associated with PAH emissions.

Augmented surveillance of antimicrobial resistance with high-throughput robotics detects transnational flow of fluoroquinolone-resistant Escherichia coli strain into poultry.

Food animal AMR surveillance programs assess only small numbers of Escherichia coli (from 100 to 600 per animal class) nationally each year, severely limiting the evaluation of public health risk(s). Here we demonstrate an affordable approach for early detection of emerging resistance on a broad scale that can also accurately characterize spatial and temporal changes in resistance. Caecal samples (n = 295) obtained from 10 meat poultry were screened using high-throughput robotics. Initial screening via agar dilution (5310 plates) quantified AMR carriage (cfu/g) for each sample. Ciprofloxacin-resistant isolates (n = 91) proceeded to downstream broth microdilution susceptibility testing. A subset of 28 ciprofloxacin-resistant isolates underwent WGS and phylogenetic analysis. Intra- and inter-flock carriage of resistance varied with drug class. Ampicillin and tetracycline resistance was ubiquitous to most birds in all flocks with an average carriage rate of 5.8 log10 cfu/g. Gentamicin and ciprofloxacin-resistant E. coli colonized fewer birds, and had an average carriage rate of 1.2 log10 cfu/g and 1.0 log10 cfu/g of faeces, respectively. Resistance to extended-spectrum cephalosporins was absent. ST354 was the dominant ST among the WGS isolates, but they demonstrated markedly lower resistance gene carriage than their international counterparts. These data amply demonstrate the ineffectiveness of commonly relied-on approaches to AMR surveillance for achieving early detection of emergence, or for measuring spatial and temporal resistance trends. Genetic analysis suggested there has been transnational flow of a ciprofloxacin-resistant strain into Australian poultry flocks, explaining their detection in a nation that prohibits fluoroquinolone use in poultry.

Public Health Risk Evaluation through Mathematical Optimization in the Process of PPPs.

The public sector is becoming increasingly appealing. In the context of declining public money to support health studies and public health interventions, public-private partnerships with entities (including government agencies and scientific research institutes) are becoming increasingly important. When forming this type of cooperation, the participants highlight synergies between the private partners and the public's missions or goals. The tasks of private and public sector actors, on the other hand, frequently diverge significantly. The integrity and honesty of public officials, institutions, trust, and faith in those individuals and institutions may all be jeopardized by these collaborations. In this study, we use the institutional corruption framework to highlight systemic concerns raised by PPPs affiliated with the governments of one of South Asia's countries. Overall analytical frameworks for such collaborations tend to downplay or disregard these systemic impacts and their ethical implications, as we argue. We offer some guidelines for public sector stakeholders that want to think about PPPs in a more systemic and analytical way. Partnership as a default paradigm for engagement with the private sector needs to be reconsidered by public sector participants. They also need to be more vocal about which goals they can and cannot fulfill, given the limitations of public financing resources.

Evaluation of Public-Health Risk of Heavy Metals Contaminants and Physicochemical Parameters in Adulteration Palm Oil Commonly Consumed in Calabar, Nigeria

Edible palm oil has been the parity of the human diet from generation to generation and has contributed both to nutrition and health. These studies investigated some selected heavy metals and physicochemical parameters in palm oil. Eleven (11) samples of ready-consumed edible palm oil were bought randomly from the selected market in calabar metropolis. The samples were digested with 25ml of concentrated H2SO4, for heavy metals analysis using Atomic Absorption Spectrophotometer (AAS). The physiochemical parameters in selected markets include the following FFA, IV, PV, and protein content were also analyzed using standard methods. The results showed that FFA value range from 9.26 to 12%, Iodine value range from 45.78 to 21.40 MgKOH/g, Peroxide value range from 3.60 to 0.03 Meq/kg, and protein content ranges from 0.06 to 0.2 mg were significantly (p<0.05) higher in some markets in comparison to the control. The results of heavy metals showed that Zn 8.06±0.06, Cd 1.01±0.05, N 1.00±0.00, C 125.91±0.09, Pb 9.30±0.07 Cobalt, Lead zinc were above the detectable limit of the WHO standard while Cd and Ni were within the permissibility limit. The results obtained from this study indicate that the palm oil sold in calabar metropolis may cause a public health risk if proper monitoring is not maintained by regulatory agencies. Thus, there is a need for improved screening of our local processed palm oil from the time of production to the time of consumption.

Public Health Risk Assessment and Prevention Based on Big Data.

In order to improve the ability of public health risk assessment in the context of community collaborative prevention and control, a mathematical model of public health risk assessment in the context of community collaborative prevention and control based on the integration and balanced allocation of big data features in the prevention horizon is proposed. The constraint parameter model of public health risk assessment under the background of community collaborative prevention and control is constructed, the method of dynamic feature analysis of joint prevention and control is adopted to realize the dynamic risk point detection of public health risk assessment data and the integration of constraint mechanism related feature points, and the fuzzy dynamic statistical feature matching method is adopted to carry out the adaptive dynamic statistics and resource balanced allocation analysis of public health risk assessment set under the background of community collaborative prevention and control. A public health risk parameter fusion model is established under the background of community collaborative prevention and control, the methods of balanced resource allocation and joint management and control are combined to realize balanced scheduling and prevention area block matching in the process of dynamic parameter estimation of public health risk evaluation data under the background of community collaborative prevention and control, the correlation distribution of public health risk under the background of community collaborative prevention and control is taken as the cost function, and balanced allocation is realized according to the statistical information sampling results of public health risk evaluation data under the background of community collaborative prevention and control. Combined with differential clustering analysis, the data clustering and attribute merging of public health risk assessment under the background of community collaborative prevention and control are realized, and the mathematical modeling optimization of public health risk assessment under the background of community collaborative prevention and control is realized. The simulation results show that this method has good adaptability, high degree of parameter fusion, and strong ability of matching risk prevention areas and balancing resource allocation in the context of community collaborative prevention and control.

Temporal variations and spatial distributions of gaseous and particulate air pollutants and their health risks during 2015-2019 in China.

Air quality has been significantly improved in China in recent years; however, our knowledge of the long-term changes in health risks from exposure to air pollutants remain less understood. Here we investigated the temporal variations and spatial distributions of six criteria pollutants (SO2, NO2, O3, CO, PM2.5 and PM10) in Beijing-Tianjin-Hebei (BTH), Yangtze River Delta (YRD) and Pearl River Delta (PRD) during 2015-2019. SO2 showed 36-60% reductions in three regions, comparatively, NO2 decreased by 3-17% in BTH and YRD and had a 5% increase in PRD. PM2.5 and PM10 showed the largest reductions in BTH (30-33%) and the lowest in PRD (7-13%), while O3 increased by 9% during 2015-2019 particularly in BTH and YRD. Assuming that only air pollutants above given thresholds exert excess risk (ERtotal) of mortality, we found that the different variations of pollutants have caused ERtotal in BTH decreasing significantly from 4.8% in 2015 to 2.0% in 2019, while from 1.9% to 1.0% in YRD, and a small change in PRD. These results indicate substantially decreased health risks of mortality from exposure to air pollutants as a response to improved air quality. Overall, PM2.5 dominated ERtotal accounting for 42-53% in BTH and 58-64% in YRD with steadily increased contributions, yet ERtotal presented strong seasonal dependence on air pollutants with largely increased contribution of O3 in summer. The ERtotal caused by SO2 was decreased substantially and became negligible except in winter in BTH, while NO2 only played a role in winter. We also found that ERPM2.5 was compositional dependent with organics being the major contributor at low ERPM2.5 while nitrate was more important at high ERPM2.5. Our results highlight that evaluation of public health risks of air pollution needs to consider chemical differences of PM in different regions in addition to dominant air pollutants in different seasons.

Evaluation of public health risk for Escherichia coli O157:H7 in cilantro

This study sought to model the growth and die-off of Escherichia coli (E. coli) O157:H7 along the cilantro supply chain from farm-to-fork to investigate its risk to public health. Contributing factors included in the model were on farm contamination from irrigation water and soil, solar radiation, harvesting, and transportation and storage times and temperatures. The developed risk model estimated the microbiological risks associated with E. coli O157:H7 in cilantro and determined the parameters that had the most effect on the estimated number of illnesses per year so future mitigation strategies could be applied. Results showed a similar decrease in the E. coli O157:H7 (median values) concentrations along the supply chain for cilantro grown in both winter and summer weather conditions. With an estimated 0.1% prevalence of E. coli O157:H7 contamination for cilantro post-harvest used for illustration, the model predicted the probability of illness from consuming fresh cilantro as very low with fewer than two illnesses per every one billion servings of cilantro (1.6 × 10−9; 95th percentile). Although rare, 3.7% and 1.6% of scenarios run in this model for summer and winter grown cilantro, respectively, result in over 10 cases per year in the United States. This is reflected in real life where illnesses from cilantro are seen rarely but outbreaks have occurred. Sensitivity analysis and scenario testing demonstrated that ensuring clean and high quality irrigation water and preventing temperature abuse during transportation from farm to retail, are key to reducing overall risk of illness.

Occurrence of human pathogenic bacteria carrying antibiotic resistance genes revealed by metagenomic approach: A case study from an aquatic environment

Antibiotic resistance genes (ARGs), human pathogenic bacteria (HPB), and HPB carrying ARGs are public issues that pose a high risk to aquatic environments and public health. Their diversity and abundance in water, intestine, and sediments of shrimp culture pond were investigated using metagenomic approach. A total of 19 classes of ARGs, 52 HPB species, and 7 species of HPB carrying ARGs were found. Additionally, 157, 104, and 86 subtypes of ARGs were detected in shrimp intestine, pond water, and sediment samples, respectively. In all the samples, multidrug resistance genes were the highest abundant class of ARGs. The dominant HPB was Enterococcus faecalis in shrimp intestine, Vibrio parahaemolyticus in sediments, and Mycobacterium yongonense in water, respectively. Moreover, E. faecalis (contig Intestine_364647) and Enterococcus faecium (contig Intestine_80272) carrying efrA, efrB and ANT(6)-Ia were found in shrimp intestine, Desulfosaricina cetonica (contig Sediment_825143) and Escherichia coli (contig Sediment_188430) carrying mexB and APH(3′)-IIa were found in sediments, and Laribacter hongkongensis (contig Water_478168 and Water_369477), Shigella sonnei (contig Water_880246), and Acinetobacter baumannii (contig Water_525520) carrying sul1, sul2, ereA, qacH, OXA-21, and mphD were found in pond water. Mobile genetic elements (MGEs) analysis indicated that horizontal gene transfer (HGT) of integrons, insertion sequences, and plasmids existed in shrimp intestine, sediment, and water samples, and the abundance of integrons was higher than that of other two MGEs. The results suggested that HPB carrying ARGs potentially existed in aquatic environments, and that these contributed to the environment and public health risk evaluation.

Sewage-specific enterococcal bacteriophages and multiple water quality parameters for coastal water quality assessment.

Coastal water quality is deteriorating worldwide. Water quality monitoring is therefore essential for public health risk evaluation and the management of water bodies. This study investigated the feasibility of using bacteriophages of Enterococcus faecalis as sewage-specific faecal indicators, together with physicochemical (dissolved oxygen, pH, temperature and total suspended solids) and biological parameters, to assess coastal water quality using multivariate analysis incorporating non-detects. The principal component and cluster analyses demonstrated that coastal water quality was mostly influenced by biological parameters, including Escherichia coli and total coliforms, which were found in all 31 sampling sites, and enterococci, which was found in all but two sampling sites. The enterococcal bacteriophages AIM06 and SR14 were detected in 17 and 18 samples at concentrations up to 1,815 and 2,790 PFU/100 mL, respectively. Both bacteriophages co-presented in approximately 80% of phage-positive samples, and the concentrations at each site were not significantly different. Overall, either bacteriophage could be used to differentiate high- and low-level coastal water pollution, as grouped by cluster analysis. This study is the first to investigate the suitability of sewage-specific bacteriophages of E. faecalis for monitoring coastal water quality and emphasises the importance of a multivariate analysis with non-detects to facilitate coastal water quality monitoring and management.

Pathogenesis and Transmission of Novel Highly Pathogenic Avian Influenza H5N2 and H5N8 Viruses in Ferrets and Mice.

A novel highly pathogenic avian influenza (HPAI) H5N8 virus, first detected in January 2014 in poultry and wild birds in South Korea, has spread throughout Asia and Europe and caused outbreaks in Canada and the United States by the end of the year. The spread of H5N8 and the novel reassortant viruses, H5N2 and H5N1 (H5Nx), in domestic poultry across multiple states in the United States pose a potential public health risk. To evaluate the potential of cross-species infection, we determined the pathogenicity and transmissibility of two Asian-origin H5Nx viruses in mammalian animal models. The newly isolated H5N2 and H5N8 viruses were able to cause severe disease in mice only at high doses. Both viruses replicated efficiently in the upper and lower respiratory tracts of ferrets; however, the clinical symptoms were generally mild, and there was no evidence of systemic dissemination of virus to multiple organs. Moreover, these influenza H5Nx viruses lacked the ability to transmit between ferrets in a direct contact setting. We further assessed viral replication kinetics of the novel H5Nx viruses in a human bronchial epithelium cell line, Calu-3. Both H5Nx viruses replicated to a level comparable to a human seasonal H1N1 virus, but significantly lower than a virulent Asian-lineage H5N1 HPAI virus. Although the recently isolated H5N2 and H5N8 viruses displayed moderate pathogenicity in mammalian models, their ability to rapidly spread among avian species, reassort, and generate novel strains underscores the need for continued risk assessment in mammals. In 2015, highly pathogenic avian influenza (HPAI) H5 viruses have caused outbreaks in domestic poultry in multiple U.S. states. The economic losses incurred with H5N8 and H5N2 subtype virus infection have raised serious concerns for the poultry industry and the general public due to the potential risk of human infection. This recent outbreak underscores the need to better understand the pathogenesis and transmission of these viruses in mammals, which is an essential component of pandemic risk assessment. This study demonstrates that the newly isolated H5N2 and H5N8 viruses lacked the ability to transmit between ferrets and exhibited low to moderate virulence in mammals. In human bronchial epithelial (Calu-3) cells, both H5N8 and H5N2 viruses replicated to a level comparable to a human seasonal virus, but significantly lower than a virulent Asian-lineage H5N1 (A/Thailand/16/2004) virus. The results of this study are important for the evaluation of public health risk.

Evaluation of public health risk. A new instrument for environmental management in Chile

One of the main challenges in environmental management is to prevent the public health impact of projects that can cause pollution. To tackle this problem, the new Chilean bill on environmental management has defined the need to determine the potential health risks of a given Project. This paper gives a summary of the method used for risk evaluation and its evolution. Its incorporation in the Environmental Impact Evaluation System is proposed, to guarantee an effective prevention of the potential risks on health of new projects.

Level-1, -2 and -3 PSA for AHWR

In nuclear reactor probabilistic safety analyses (PSAs), risk is usually defined by the frequency and magnitude of radioactive releases to the environment ( Generic CANDU, 2002). An integrated Level-1, -2 and -3 PSA have been carried out for thorium based natural circulation driven advanced heavy water reactor (AHWR). A Level-1 PSA models accident sequences up to the point at which the reactor core either reaches a stable condition or becomes severely damaged, releasing large amounts of radionuclides into the containment. The probabilistic aspects of the analysis focus on the performance and reliability of nuclear plant systems and station staff in response to plant upsets. A Level-2 PSA examines severe reactor accidents through a combination of probabilistic and deterministic approaches, in order to determine the release of radionuclides from containment, including the physical processes that are involved in the loss of structural integrity of the reactor core ( Generic CANDU, 2002). A Level-3 PSA goes through the short and long term (radiological) effects on the public ( Fullwood, 2000). In this study the risk associated with internal events is only addressed. In the first phase, Level-1 PSA has been carried out to identify postulated initiating events (PIEs) which may lead to severe core damage (SCD) for the reactor. In the second phase, a Level-2 PSA examines two enveloping severe accidents through a combination of probabilistic and deterministic approaches and determines the release of radionuclides from containment. In the third phase, a Level-3 PSA is carried out for the transport of radionuclides through the environment and for the evaluation of public health risk for the two scenarios considered. The salient findings are presented in the paper.

Evaluation of public health risks at recreational beaches in Lake Michigan via detection of enteric viruses and a human-specific bacteriological marker

Each year the National Resource Defense Council addresses the quality of US beaches by routine bacterial indicators. In the Great Lakes region the indicator used is Escherichia coli and for 2007 more beaches were closed and impacted than ever before. In this study, water quality was addressed at two Lake Michigan Beaches over the 2004 swimming season by monitoring infectious enteric viruses by cell culture and integrated PCR and for a human sewage marker based on the Enterococcal Surface Protein ( esp). Our goals for this study were to 1) examine the occurrence and variety of human enteric viruses present during peak usage of the beaches 2) determine key variables for development of predictive models for viruses; and 3) use quantitative risk assessment to estimate the potential health impact. Our results demonstrate that for both beaches predictive models of virus pollution were best described utilizing physical parameters like wind speed, wind direction and water temperature. The esp marker was not predictive of human viruses. The daily risk of acquiring a viral infection at either of the beaches ranged from 0.2 to 2.4/1000 swimmers using a quantitative microbial risk assessment model, with three swims during a day at the beach for children and over the season, the risk was 9–15/1000 swimmers using adenovirus as the model. Conclusions: Lake Michigan recreational beaches are being adversely impacted by human fecal pollution. Monitoring for the traditional indicators of water quality does not address viral risks and models can be developed and potentially used as real-time water quality forecasting tools.

96/02063 Environmental risk assessment of a coal-fired power plant by public health risk evaluation method

96/02063 Environmental risk assessment of a coal-fired power plant by public health risk evaluation method

Physiologically based assessment of human exposure to urban air pollutants and its significance for public health risk evaluation.

Exact measurements or modeling of human exposures to environmental pollutants are of crucial importance for a realistic evaluation of public health risks. Current concepts, however, often use assumptions that result in overly conservative assessments of public health risks. Too frequently the dose of the pollutant retained in the body is approximated by oversimplified predictions assuming that all that is inhaled remains in the organism, that pollutant concentrations in various microenvironments are identical to those recorded by remote monitors, that the residence indicates the site where people spend all their time, and that the urban population is continuously exposed to outdoor air for 24 hr/day and 70 years/lifetime. The review shows that in intermittent exposures only a fraction of inhaled toxicants remains in the body, that pollutant concentrations differ largely from one microenvironment to another, and that human activity patterns must be incorporated in every realistic exposure assessments. Specifically, the probability of being exposed to a short peak of ozone is predetermined in variable urban concentrations primarily by the coincidence of exercising outdoors at the time and site of elevated ozone levels. When combined with a physiologically based exposure evaluation, this probabilistic approach provides a scientifically sound estimate of actual occurrences of adverse exposures and a realistic assessment of potential health hazards.

Physiologically Based Assessment of Human Exposure to Urban Air Pollutants and Its Significance for Public Health Risk Evaluation

Physiologically Based Assessment of Human Exposure to Urban Air Pollutants and Its Significance for Public Health Risk Evaluation

Computer data bases for carcinogenicity and risk assessment

AbstractThis paper reviews information on computer data bases for carcinogenicity and risk assessment. The data bases included were Chemical Evaluation Search and Retrieval System (CESARS), Hazardous Substances Data Bank (HSDB), Registry of Toxic Effects of Chemical Substances (RTECS), Toxicology Information Online (TOXLINE), Cancer Literature (CANCERLIT), Chemical Carcinogenesis Research Information System (CCRIS), Public Health Risk Evaluation Database (PHRED) and Integrated Risk Information System (IRIS). Chemical records included in CESARS, HSDB and RTECS contain general information on carcinogenicity. TOXLINE and CANCERLIT are bibliographic data bases for toxicological and cancer studies. CCRIS contains detailed information on carcinogenicity studies for formulation of risk assessment. PHRED contains toxicological information and cancer potency factors for formulation of risk assessment. IRIS provides detailed information for carcinogenicity assessments, slope factors, unit risks and concentrations at specified risk levels for chronic exposures to carcinogens. IRIS serves as the best source of information for risk assessment for environmental contaminants.