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Potential health risks of contaminated media linked to bioavailability and hematotoxicity of uranium-238 (238U) and thorium-232 (232Th) remain uncertain. This study investigates the relative bioavailability (RBA), histopathological, and hematological effects of acute oral exposure to 238U and 232Th in co-contaminated concrete dust using 174 female Sprague Dawley (SD) rats. In order to create a range of 238U and 232Th concentrations, concrete was spiked with uranyl and thorium nitrates (~ 50, 100, and 200 mg kg−1). Spiked concretes were then crushed, ground, sieved (≤ 75 µm), and blended uniformly to create co-contaminated concrete dust. SD rats' diet pellet was amended with co-contaminated concrete dust and orally ingested over a 48-h exposure period. The RBA values of 238U and 232Th in blood samples from rats' post-exposure were determined as 22.0% ± 0.86% to 30.8% ± 1.01% and 11.8% ± 0.14% to 13.7% ± 0.29%, respectively. Compared to 232Th, 238U blood levels of SD rats fed with co-contaminated concrete dust-amended diets were ~ 100-fold higher due to solubility differences, and 238U-RBA values were approximately 2-fold greater, revealing that their absorption rates in the gastrointestinal tract were affected by compound solubility. Post-acute 238U and 232Th ingestion from co-contaminated concrete dust demonstrate noticeable histopathological and hematological alterations, implying that intake of 238U and 232Th in co-contaminated concrete dust can lead to erythrocytes damage and elevated hematological attributes. Our study would be beneficial for an adequate understanding of the health implications caused by the acute oral exposures of 238U and 232Th in co-contaminated concrete dust, especially in the bioavailability and toxicity assessment. [ABSTRACT FROM AUTHOR]

Organophosphorus nerve agents (OPNA) are hazardous environmental exposures to the civilian population and have been historically weaponized as chemical warfare agents (CWA). OPNA exposure can lead to several neurological, sensory, and motor symptoms that can manifest into chronic neurological illnesses later in life. There is still a large need for technological advancement to better understand changes in brain function following OPNA exposure. The human-relevant in vitro multi-electrode array (MEA) system, which combines the MEA technology with human stem cell technology, has the potential to monitor the acute, sub-chronic, and chronic consequences of OPNA exposure on brain activity. However, the application of this system to assess OPNA hazards and risks to human brain function remains to be investigated. In a concentration-response study, we have employed a humanrelevant MEA system to monitor and detect changes in the electrical activity of engineered neural networks to increasing concentrations of the sarin surrogate 4-nitrophenyl isopropyl methylphosphonate (NIMP). We report a biphasic response in the spiking (but not bursting) activity of neurons exposed to low (i.e., 0.4 and 4 μM) versus high concentrations (i.e., 40 and 100 μM) of NIMP, which was monitored during the exposure period and up to 6 days post-exposure. Regardless of the NIMP concentration, at a network level, communication or coordination of neuronal activity decreased as early as 60 min and persisted at 24 h of NIMP exposure. Once NIMP was removed, coordinated activity was no different than control (0 mM of NIMP). Interestingly, only in the high concentration of NIMP did coordination of activity at a network level begin to decrease again at 2 days post-exposure and persisted on day 6 post-exposure. Notably, cell viability was not affected during or after NIMP exposure. Also, while the catalytic activity of AChE decreased during NIMP exposure, its activity recovered once NIMP was removed. Gene expression analysis suggests that human iPSC-derived neurons and primary human astrocytes resulted in altered genes related to the cell's interaction with the extracellular environment, its intracellular calcium signaling pathways, and inflammation, which could have contributed to how neurons communicated at a network level. [ABSTRACT FROM AUTHOR]

Abstract Background The inappropriate use of pesticides including fungicides creates severe biological hazards that can endanger fish health and impede sustainable aquaculture. Objective This study investigated the negative impacts of metiram (MET), a fungicide on the health status of Nile tilapia (Oreochromis niloticus) for a 96-hour duration as an acute exposure in a static renewal system. Methods Three hundred fish (average body weight: 37.50 ± 0.22 g) were assigned into six groups (50 fish/group) with five replicates (10 fish/replicate). Fish were exposed to various six concentrations (0, 1.5, 3, 4.5, 6, and 7.5 mg/L) of MET as a water exposure to for 96-hour without water exchange. The fish’s behavior, clinical signs, and mortalities were documented every day of the exposure period. Additionally, MET’s impact on blood profile, stress biomarkers, hepato-renal functions, immune-antioxidant status, and brain biomarker were closely monitored. Results The lethal concentration (LC50) of MET estimated using Finney’s probit technique was 3.77 mg/L. The fish’s behavior was severely impacted by acute MET exposure, as clear by an increase in surfacing, loss of equilibrium, unusual swimming, laterality, abnormal movement, and a decline in aggressive behaviors. The survivability and hematological indices (white and red blood cell count, differential white blood cell count, hematocrit value, and hemoglobin) were significantly reduced in a concentration-dependent manner following MET exposure. Acute exposure to MET (1.5–7.5 mg/L) incrementally increased stress biomarkers (nor-epinephrine, cortisol, and glucose), lipid peroxides (malondialdehyde), and brain oxidative DNA damage biomarker (8-hydroxy-2-deoxyguanosine). A hepato-renal dysfunction by MET exposure (4.5–7.5 mg/L) was evidenced by the significant increase in the alanine and aspartate aminotransferases and creatinine values. Moreover, a substantial decline in the immune parameters (lysozyme, complement 3, serum bactericidal activity, and antiprotease activity) and antioxidant variables (total antioxidant capacity, superoxide dismutase, and glutathione peroxidase) resulted from acute MET exposure. Conclusion According to these findings, the 96-hour LC50 of MET in Nile tilapia was 3.77 mg/L. MET exposure triggered toxicity in Nile tilapia, as seen by alterations in fish neuro-behaviors, immune-antioxidant status, hepato-renal functioning, and signifying physiological disturbances. This study emphasizes the potential ecological dangers provoked by MET as an environmental contaminant to aquatic systems. However, the long-term MET exposure is still needed to be investigated.

Aim: Today, there is a lack of research studies concerning human acute exposure to nanoparticles (NPs). Our investigation aimed to simulate real-world acute inhalation exposure to NPs released during work with dental nanocomposites in a dental office or technician laboratory. Methods: Blood samples from female volunteers were processed before and after inhalation exposure. Transcriptomic mRNA and miRNA expression changes were analyzed. Results: We detected large interindividual variability, 90 significantly deregulated mRNAs, and 4 miRNAs when samples of participants before and after dental nanocomposite grinding were compared. Conclusion: The results suggest that inhaled dental NPs may present an occupational hazard to human health, as indicated by the changes in the processes related to oxidative stress, synthesis of eicosanoids, and cell division. We searched for a possible impact of acute inhalation exposure to nanoparticles (NPs) released during the grinding of dental nanocomposites used for teeth reconstruction. The exposure design utilized in our study simulated the acute exposure of the dental staff to the NPs. Our research fills the gaps in knowledge in the field of acute human inhalation exposure to dental nanocomposites. Results indicate that the impact of exposure to NPs is dependent on the style of working as well as on the interindividual biological variability among study subjects. Changes in expression levels of genes associated with an increase of oxidative stress, synthesis of eicosanoids (signaling molecules related to e.g., immune responses), and cell division were detected. All the observed changes may contribute to the pathogenesis of neurodegenerative disorders, carcinogenesis, or problems during pregnancy. Occupational exposure to inhaled NPs, including those generated in dental practice can pose a significant health risk, and protective measures when working with these materials should be considered. More research is needed to compare our results with chronic (long-term) exposure to similar materials to show the hazards related to their inhalation. GRAPHICAL ABSTRACT Article highlights The experimental design simulated the work of dental personnel during teeth repair. The study investigated the possible impact of acute inhalation exposure to nanoparticles (NPs) released during the grinding of dental nanocomposites on transcriptome changes. Analyses of the differential mRNA and miRNA expression were performed. Large interindividual variability in gene expression changes after exposure was detected. Significant deregulation of DDIT4, PER1, and GPR124 was detected when sampling was compared after and before exposure. Deregulation of hsa-miR-15b-5p, hsa-miR-6861-3p, hsa-miR-548o-3p, and hsa-miR-3913-5p was observed when comparing post- and pre-shift sampling. Individual occupational health risks to NP exposure led to the alteration of several biological pathways. Increased oxidative stress, synthesis of eicosanoids, or cell division may contribute to the pathogenesis of neurogenerative disorders, and carcinogenesis after NP exposure. [ABSTRACT FROM AUTHOR]

Background: The inappropriate use of pesticides including fungicides creates severe biological hazards that can endanger fish health and impede sustainable aquaculture. Objective: This study investigated the negative impacts of metiram (MET), a fungicide on the health status of Nile tilapia (Oreochromis niloticus) for a 96-hour duration as an acute exposure in a static renewal system. Methods: Three hundred fish (average body weight: 37.50 ± 0.22 g) were assigned into six groups (50 fish/group) with five replicates (10 fish/replicate). Fish were exposed to various six concentrations (0, 1.5, 3, 4.5, 6, and 7.5 mg/L) of MET as a water exposure to for 96-hour without water exchange. The fish's behavior, clinical signs, and mortalities were documented every day of the exposure period. Additionally, MET's impact on blood profile, stress biomarkers, hepato-renal functions, immune-antioxidant status, and brain biomarker were closely monitored. Results: The lethal concentration (LC50) of MET estimated using Finney's probit technique was 3.77 mg/L. The fish's behavior was severely impacted by acute MET exposure, as clear by an increase in surfacing, loss of equilibrium, unusual swimming, laterality, abnormal movement, and a decline in aggressive behaviors. The survivability and hematological indices (white and red blood cell count, differential white blood cell count, hematocrit value, and hemoglobin) were significantly reduced in a concentration-dependent manner following MET exposure. Acute exposure to MET (1.5–7.5 mg/L) incrementally increased stress biomarkers (nor-epinephrine, cortisol, and glucose), lipid peroxides (malondialdehyde), and brain oxidative DNA damage biomarker (8-hydroxy-2-deoxyguanosine). A hepato-renal dysfunction by MET exposure (4.5–7.5 mg/L) was evidenced by the significant increase in the alanine and aspartate aminotransferases and creatinine values. Moreover, a substantial decline in the immune parameters (lysozyme, complement 3, serum bactericidal activity, and antiprotease activity) and antioxidant variables (total antioxidant capacity, superoxide dismutase, and glutathione peroxidase) resulted from acute MET exposure. Conclusion: According to these findings, the 96-hour LC50 of MET in Nile tilapia was 3.77 mg/L. MET exposure triggered toxicity in Nile tilapia, as seen by alterations in fish neuro-behaviors, immune-antioxidant status, hepato-renal functioning, and signifying physiological disturbances. This study emphasizes the potential ecological dangers provoked by MET as an environmental contaminant to aquatic systems. However, the long-term MET exposure is still needed to be investigated. [ABSTRACT FROM AUTHOR]

The hunt for potential remedies for cadmium (Cd) toxicity is an exciting topic of research that is now being investigated globally. This study investigated amelioration of cadmium-induced biochemical alterations in heart tissues of Wistar rats using bee honey. Six groups (1-6) of thirty adult Wistar rats were used for the study: control, sub-chronic Cd exposure, sub-chronic Cd exposure plus honey, acute Cd exposure, acute Cd exposure plus honey, and honey only. For the sub-chronic investigation, Cd chloride (CdCl2) was injected intraperitoneally (IP) at a dose of 2 mg/kg body weight every two days for a period of four weeks, and for the acute trial, a dose of 4 mg/kg body weight was injected IP 12 hours prior to sacrifice. 1 ml/kg of body weight of honey was given orally once every day for four weeks. According to the study, groups 2 and 4 had substantially greater levels of lipid peroxidation and acid phosphatase (ACP) activity in the heart tissues compared to group 1. Catalase (CAT), superoxide dismutase (SOD), alanine aminotransferase (ALT), aspartate aminotransferase (AST), and alkaline phosphatase (ALP) enzyme activity were also significantly decreased. This study shows that honey treatment significantly ameliorates Cd-induced toxicities in heart tissues by suppressing lipid peroxidation and normalizing antioxidant enzyme activity. Further work should be done to identify specific phytochemical antioxidants and its mode of action in ameliorating Cd-induced toxicities in heart tissues. [ABSTRACT FROM AUTHOR]

Organophosphorus nerve agents (OPNA) are hazardous environmental exposures to the civilian population and have been historically weaponized as chemical warfare agents (CWA). OPNA exposure can lead to several neurological, sensory, and motor symptoms that can manifest into chronic neurological illnesses later in life. There is still a large need for technological advancement to better understand changes in brain function following OPNA exposure. The human-relevant in vitro multi-electrode array (MEA) system, which combines the MEA technology with human stem cell technology, has the potential to monitor the acute, sub-chronic, and chronic consequences of OPNA exposure on brain activity. However, the application of this system to assess OPNA hazards and risks to human brain function remains to be investigated. In a concentration-response study, we have employed a human-relevant MEA system to monitor and detect changes in the electrical activity of engineered neural networks to increasing concentrations of the sarin surrogate 4-nitrophenyl isopropyl methylphosphonate (NIMP). We report a biphasic response in the spiking (but not bursting) activity of neurons exposed to low (i.e., 0.4 and 4 μM) versus high concentrations (i.e., 40 and 100 μM) of NIMP, which was monitored during the exposure period and up to 6 days post-exposure. Regardless of the NIMP concentration, at a network level, communication or coordination of neuronal activity decreased as early as 60 min and persisted at 24 h of NIMP exposure. Once NIMP was removed, coordinated activity was no different than control (0 μM of NIMP). Interestingly, only in the high concentration of NIMP did coordination of activity at a network level begin to decrease again at 2 days post-exposure and persisted on day 6 post-exposure. Notably, cell viability was not affected during or after NIMP exposure. Also, while the catalytic activity of AChE decreased during NIMP exposure, its activity recovered once NIMP was removed. Gene expression analysis suggests that human iPSC-derived neurons and primary human astrocytes resulted in altered genes related to the cell’s interaction with the extracellular environment, its intracellular calcium signaling pathways, and inflammation, which could have contributed to how neurons communicated at a network level.

Context: High temperature and oil pollution are typical examples of environmental stress to sea cucumber (Apostichopus japonicus) in northern China. Aims: Evaluate the combined effects of high temperature and oil pollution on the immune responses of sea cucumbers. Methods: In this study, we investigated the immune responses in the respiratory tree of sea cucumber subjected to the optimal temperature (16°C), high temperature (26°C), Oman crude oil (OCO) water-accommodated fractions (WAF) at 16°C (WAF + 16°C) and OCO WAF at 26°C (WAF + 26°C) for 48 h. Key results: All three treatments significantly up-regulated total antioxidant capacity and disturbed active oxygen species homeostasis in sea cucumbers. Moreover, all three treatments caused immune-enzyme activity disorders, manifested by a significant increase in acid–alkaline phosphatase and nitric oxide synthase activities and a noticeable decline in lysozyme activity. Conclusions: Combining the integrated biomarker-response index (WAF + 26°C > 26°C > WAF + 16°C), the combined stress could result in a more adverse effect on the immune responses of sea cucumbers than do high temperature or oil pollution alone, which might further exacerbate the health challenges for sea cucumbers in response to environmental stress. Implications: This study has provided an insight into the immune impacts in benthic organisms caused by high temperature and oil pollution. We investigated the immune responses in the respiratory tree of sea cucumber (Apostichopus japonicus) to high temperature, oil pollution, and the combined stress of high temperature and oil pollution. We found that acute exposure to oil pollution may have affect the immune function of sea cucumbers, whereas high temperature may exacerbate the health challenges of sea cucumbers subjected to environmental stress. [ABSTRACT FROM AUTHOR]

An integrated environmental health exposure assessment (IEHA) refers to the integration of human biomonitoring data (HBM) and environmental measurements and aims to optimize the exposure assessment process. Due to lack of data, this approach remains an issue during chemical incidents. This study aims to explore integrated exposure approaches for assessing human health risks during chemical incidents. Based on the Preferred Reporting Items of Systematic reviews and Meta‐Analyses statement, a literature analysis was performed. A level of confidence ranging from 1 to 4 was established to define the quality and strength of data used to undertake an IEHA approach. Twenty‐seven articles (n = 18) and texts (n = 9) from Europe (41%) and the United States (37%) were analyzed. Among the 18 scientific articles, 61% (n = 11) presented a quantitative approach and 17% (n = 3) presented a qualitative approach. Quantitative approaches must be based on accurate data, coupled with predictive models. Of all the scientific papers, 40% (n = 7) responded to a confidence level greater than or equal to 2. Uncertainties detected through the integrated exposure approaches were related to input data, analytical methods, and HBM reference value interpretations. During chemical incidents, direct measurements were the most relevant data. Few scientific studies have developed an integrated approach during emergency situations. However, when this was used, they presented a high level of confidence by defining levels of exposure that support decision‐making processes. Despite the multiple approaches, there was a lack of guidelines allowing an integrated risk assessment to be performed during an emergency chemical exposure. Integr Environ Assess Manag 2024;20:481–497. © 2023 SETAC Key Points: Despite the scientific sources and the multiple specific approaches, there was a lack of good practice guidelines allowing an integrated risk assessment to be carried out during an emergency chemical exposure.There is a need to integrate human biomonitoring data and direct environmental measures to refine exposure assessment and protect the environment and public health.Integrated assessment allows better support for decision‐making during a chemical incident assessment. [ABSTRACT FROM AUTHOR]

Abstract Reducing the time to settlement and metamorphosis of abalone larvae is critical for ensuring that abalone larvae settle within the seeding site for ocean ranching or to increase production in hatcheries. This study investigated the effect of biological (planktonic Nitzschia sp.) and chemical (potassium chloride) cues in inducing settlement and metamorphosis of abalone larvae Haliotis midae on diatom‐coated plastic sheets. Larvae were exposed to different concentrations of KCl (10–20 mM), with settlement being highest at 10 mM in the first 20 h. Settlement of larvae exposed to a combined KCl and Nitzschia treatment for 24 h was highest, followed by larvae exposed to KCl for 12 h, while larvae exposed to KCl for 24 h, and both controls (12 and 24 h) had the lowest settlement. However, in both experiments, larval settlement in all treatments declined after 24 h of exposure, while that of the controls (no added settlement cues) increased and surpassed the other treatments after 24 h. Finally, the settlement was very low on uncoated sheets, compared to diatom‐coated sheets, regardless of exposure to different combinations of KCl and Nitzschia. The exposure period's results should be interpreted with caution when drawing biological conclusions for field studies. This is due to the dramatic decrease in mean settlement post‐exposure to the cue. Therefore, we hypothesize that exposure of H. midae larvae to 10 mM KCl and Nitzschia sp. will not enhance settlement in the ocean, as the inducers are primarily only effective at a KCl concentration level equal to 10 mM for 12 h. However, long‐term exposure to KCl and Nitzschia over 24 h could be used in hatcheries to improve the settlement of H. midae larvae.

Reducing the time to settlement and metamorphosis of abalone larvae is critical for ensuring that abalone larvae settle within the seeding site for ocean ranching or to increase production in hatcheries. This study investigated the effect of biological (planktonic Nitzschia sp.) and chemical (potassium chloride) cues in inducing settlement and metamorphosis of abalone larvae Haliotis midae on diatom‐coated plastic sheets. Larvae were exposed to different concentrations of KCl (10–20 mM), with settlement being highest at 10 mM in the first 20 h. Settlement of larvae exposed to a combined KCl and Nitzschia treatment for 24 h was highest, followed by larvae exposed to KCl for 12 h, while larvae exposed to KCl for 24 h, and both controls (12 and 24 h) had the lowest settlement. However, in both experiments, larval settlement in all treatments declined after 24 h of exposure, while that of the controls (no added settlement cues) increased and surpassed the other treatments after 24 h. Finally, the settlement was very low on uncoated sheets, compared to diatom‐coated sheets, regardless of exposure to different combinations of KCl and Nitzschia. The exposure period's results should be interpreted with caution when drawing biological conclusions for field studies. This is due to the dramatic decrease in mean settlement post‐exposure to the cue. Therefore, we hypothesize that exposure of H. midae larvae to 10 mM KCl and Nitzschia sp. will not enhance settlement in the ocean, as the inducers are primarily only effective at a KCl concentration level equal to 10 mM for 12 h. However, long‐term exposure to KCl and Nitzschia over 24 h could be used in hatcheries to improve the settlement of H. midae larvae. [ABSTRACT FROM AUTHOR]

This study was aimed to evaluate the effect of sublethal concentrations of lead chloride on physiological and histopathological studies in Gambusia affinis . A total of 500 fish were collected from the bank of the river east of Mosul city. The fish in the aquarium were divided into five groups (control, acute exposure(20,25mg/l) and chronic exposure(5,10mg/l)). The bioaccumulation of lead in acute and chronic periods of exposure showed a significant difference in values between control and treatment. The greatest level was seen in the kidney of fish treated with lead dichloride at 10 mg/l for 30 days. The level of antioxidant Glutathione has a significant decrease in different kidneys of fish treated with pbcl2 exposed to acute and chronic concentrations. The lowest decrease was seen in kidneys of fish treated with Pbcl2 at 10 mg/l for a month. At the same time, a significant increase in lipid peroxidation (malondialdehyde) level was seen in all kidney treated with pbcl2. Histological study of the kidney showed varying degrees of pathological lesions. The glomeruli in the kidney shrank, and degeneration of Bowman's capsule. The Pb accumulation increases with increasing concentration and period of exposure. Both acute and chronic effects caused a change in the level of antioxidants and histopathological changes in kidney of the fish. Histopathological study may be a useful indicator for determining the extent of aquatic contamination. It could be concluded that the kidney changes caused by lead exposures in fish may serve as a biomarker for the contamination of sub-lethal levels of heavy metals and other anthropogenic contaminants. [ABSTRACT FROM AUTHOR]

Yueming Zhang,1– 3 Ziyao Guo,1,2 Wen Zhang,3 Qinyuan Li,1,2 Yan Zhao,1,2 Zhili Wang,1,2 Zhengxiu Luo1,2 1Department of Respiratory Medicine, Children’s Hospital of Chongqing Medical University, Chongqing, People’s Republic of China; 2National Clinical Research Center for Child Health and Disorders, Ministry of Education Key Laboratory of Child Development and Disorders, Chongqing Key Laboratory of Pediatrics, Chongqing, People’s Republic of China; 3Department of Respiratory, Xi’an Children’s Hospital, Xi’an, Shaanxi, People’s Republic of ChinaCorrespondence: Zhengxiu Luo, Department of Respiratory Medicine, Children’s Hospital of Chongqing Medical University, Chongqing, People’s Republic of China, Email luozhengxiu816@hospital.cqmu.edu.cnObjective: The objective of this study was to conduct a systematic review and meta-analysis to identify the adverse effects of acute PM2.5 exposure on lung function in children.Design: Systematic review and meta-analysis. Setting, participants and measures: Eligible studies analyzing PM2.5 level and lung function in children were screened out. Effect estimates of PM2.5 measurements were quantified using random effect models. Heterogeneity was investigated with Q-test and I2 statistics. We also conducted meta-regression and sensitivity analysis to explore the sources of heterogeneity, such as different countries and asthmatic status. Subgroup analyses were conducted to determine the effects of acute PM2.5 exposure on children of different asthmatic status and in different countries.Results: A total of 11 studies with 4314 participants from Brazil, China and Japan were included finally. A 10 μg/m3 increase of PM2.5 was associated with a 1.74L/min (95% CI: − 2.68, − 0.90) decrease in peak expiratory flow (PEF). Since the asthmatic status and country could partly explain the heterogeneity, we conducted the subgroup analysis. Children with severe asthma were more susceptible to PM2.5 exposure (− 3.11 L/min per 10 μg/m3 increase, 95% CI − 4.54, − 1.67) than healthy children (− 1.61 L/min per 10 μg/m3 increase, 95% CI − 2.34, − 0.91). In the children of China, PEF decreased by 1.54 L/min (95% CI − 2.33, − 0.75) with a 10 μg/m3 increase in PM2.5 exposure. In the children of Japan, PEF decreased by 2.65 L/min (95% CI − 3.82, − 1.48) with a 10 μg/m3 increase of PM2.5 exposure. In contrast, no statistic association was found between every 10 μg/m3 increase of PM2.5 and lung function in children of Brazil (− 0.38 L/min, 95% CI − 0.91, 0.15).Conclusion: Our results demonstrated that the acute PM2.5 exposure exerted adverse impacts on children’s lung function, and children with severe asthma were more susceptible to the increase of PM2.5 exposure. The impacts of acute PM2.5 exposure varied across different countries.Keywords: particulate matter 2.5, PM2.5, children, peak expiratory flow, PEF, acute exposure, meta-analysis

Ionizing radiation (IR) impact cellular and molecular processes that require chromatin remodelling relevant for cellular integrity. However, the cellular implications of ionizing radiation (IR) delivered per time unit (dose rate) are still debated. This study investigates whether the dose rate is relevant for inflicting changes to the epigenome, represented by chromatin accessibility, or whether it is the total dose that is decisive. CBA/CaOlaHsd mice were whole-body exposed to either chronic low dose rate (2.5 mGy/h for 54 d) or the higher dose rates (10 mGy/h for 14 d and 100 mGy/h for 30 h) of gamma radiation (60Co, total dose: 3 Gy). Chromatin accessibility was analysed in liver tissue samples using Assay for Transposase-Accessible Chromatin with high-throughput sequencing (ATAC-Seq), both one day after and over three months post-radiation (>100 d). The results show that the dose rate contributes to radiation-induced epigenomic changes in the liver at both sampling timepoints. Interestingly, chronic low dose rate exposure to a high total dose (3 Gy) did not inflict long-term changes to the epigenome. In contrast to the acute high dose rate given to the same total dose, reduced accessibility at transcriptional start sites (TSS) was identified in genes relevant for the DNA damage response and transcriptional activity. Our findings link dose rate to essential biological mechanisms that could be relevant for understanding long-term changes after ionizing radiation exposure. However, future studies are needed to comprehend the biological consequence of these findings.

Simple Summary: Several lab studies have shown that pesticides are causing sublethal effects on bees; however, little is known about their impact in actual field conditions. Continuous surveillance of the bees in the field will help monitor their pesticide exposure and better understand their impact on bee health. This study investigated the potential use of a new optical sensor, coupled with machine learning, to automatically identify flying insects, as an approach to monitoring the sublethal effects of pesticides on insects. To do so, bumblebees, Bombus terrestris, were exposed to field-realistic doses of a neonicotinoid pesticide, and their flight activity was recorded by the sensor. Through the data acquired, the investigation focused on whether the machine learning algorithm could distinguish the flight events that were created by the healthy bumblebees and the bumblebees that had been exposed to sublethal doses of the pesticide. The results showed that the algorithm could differentiate flight events, indicating the promise of the sensor as a continuous monitoring tool for bee health in the field. Among insects, bees are important pollinators, providing many vital ecosystem services. The recent pollinator decline is threatening both their diversity and abundance. One of the main drivers of this decline is the extensive use of pesticides. Neonicotinoids, one of the most popular groups of pesticides, can be toxic to bees. In fact, numerous studies have found that neonicotinoids can cause sublethal effects, which can impair the biology, physiology, and colony survival of the bees. Yet, there are still knowledge gaps, and more research is needed to better understand the interaction between neonicotinoids and bees, especially in the field. A new optical sensor, which can automatically identify flying insects using machine learning, has been created to continuously monitor insect activity in the field. This study investigated the potential use of this sensor as a tool for monitoring the sublethal effects of pesticides on bumblebees. Bombus terrestris workers were orally exposed to field-realistic doses of imidacloprid. Two types of exposures were tested: acute and chronic. The flight activity of pesticide-exposed and non-exposed bumblebees was recorded, and the events of the insect flights recorded by the sensor were used in two ways: to extract the values of the wingbeat frequency and to train machine learning models. The results showed that the trained model was able to recognize differences between the events created by pesticide-exposed bumblebees and the control bumblebees. This study demonstrates the possibility of the optical sensor for use as a tool to monitor bees that have been exposed to sublethal doses of pesticides. The optical sensor can provide data that could be helpful in managing and, ideally, mitigating the decline of pollinators from one of their most major threats, pesticides. [ABSTRACT FROM AUTHOR]

Titanium dioxide is a type of nanoparticle that is composed of one titanium atom and two oxygen atoms. One of its physicochemical activities is photolysis, which produces different reactive oxygen species (ROS). Atya lanipes shrimp affect detrital processing and illustrate the potential importance of diversity and nutrient availability to the rest of the food web. It is essential in removing sediments, which have an important role in preventing eutrophication. This study aimed to determine the toxic effect of changes in behavior and levels of oxidative stress due to exposure to titanium dioxide nanoparticles in Atya lanipes and to determine the effective concentration (EC50) for behavioral variables. The concentrations of TiO2 NPs tested were 0.0, 0.50, 1.0, 2.0, and 3.0 mg/L with the positive controls given 100 µg/L of titanium and 3.0 mg/L of TiO2 NPs ± 100 µg/L of titanium. After 24 h of exposure, significant hypoactivity was documented. The EC50 was determined to be a concentration of 0.14 mg/L. After the exposure to 10 mg/L of TiO2 NPs, oxidative stress in gastrointestinal and nervous tissues was documented. The toxic effects of this emerging aquatic pollutant in acute exposure conditions were characterized by sublethal effects such as behavior changes and oxidative stress. [ABSTRACT FROM AUTHOR]

Abstract The toxic effects of venlafaxine (VLX) on aquatic organisms have already been verified and therefore are a proven matter of concern. Herein, we evaluated zebrafish embryos/adults after acute exposure to VLX. Embryos/larvae were exposed to different concentrations of VLX (100-1000 mg/L; 1.33 as a dilution factor), to evaluate mortality/developmental changos and to analyze biomarkers (0.002-100 mg/L). For adults, mortality, genotoxicity, and biomarkers were assessed in five different concentrations of VLX (1-100 mg/L). The median lethal concentration (LC50-168h) was 274.1 mg/L for embryos/larvae, and >100 mg/L for adults (LC50-96h). VLX decreased the heart rate frequency and caused premature hatching and lack of equilibrium in embryos/larvae exposed to different concentrations ranging from 100 to 562.5 mg/L. The activity of acetylcholinesterase (AChE) was inhibited in larvae exposed to 1, 25 and 100 mg/L. Glutathione-S-transferase (GST) activity was reduced in both larvae and adults after exposure to different concentrations, mainly at 25 mg/L. For both larvae and adults, lactate dehydrogenase (LDH) activity increased after 100 mg/L of VLX exposure. No DNA damage was observed in peripheral erythrocytes. Exposure to VLX may cause adverse effects on zebrafish in their early and adult life stages, interfering with embryo-larval development, and can induce physiological disturbances in adults.

Seafood, such as mussels is rich of essential nutrients, but it could be also a source of contaminants that may cause adverse health effects. This article aimed to identify safety status of mussels harvested from Bulgarian coast. Wild and cultivated mussels (N = 17) were collected from their breeding sites in the period throughout 2021, along the Bulgarian coast of the Black Sea. Among all six regulated marine biotoxins (domoic acid, dinophysistoxin-1 (DTX1), dinophysistoxin-2 (DTX2), azaspiracid-1 (AZA1), pectenotoxin-2 (PTX2) and yessotoxin (YTX)) were determined via high performance liquid chromatography-tandem mass spectrometry. Safety of investigated samples was assessed by calculating the human exposure to detected toxins and comparing it with the legislated acute reference doses. For calculations a body weight (66 kg) and mean portion size of 400 g, recommended by EFSA were used. The presence of only PTX2, yessotoxin and some of their analogues (PTX2-seco acid (PTX2sa) and hydroxy-YTX) was confirmed in all samples. Highest calculated exposure was to YTX – 0,00013 microgram/kg bw, which is much lower than the accepted acute reference dose of 25 microgram/kg bw. Calculated exposures to pectenotoxins were more than thousand times lower than the acute reference dose of 0,8 microgram/kg bw. Estimated results indicate that no human health risk could be expected based on the analyzed mussels. Although, no human health risk was identified, a running monitoring of marine biotoxins is important as mass proliferations of harmful microalgal are hard to predict. Thus, high levels of yessotoxins and pectenotoxins might be a certain danger to consumers. The insidiousness lies in the mechanism of action of these toxins, as it is still unknown and does not allow us to have reliable information on the symptoms and problems that it develops in humans. This work presents that in mussel samples from Bulgarian coast from 2021, low levels of marine biotoxins were detected. No human health risk might be expected if mussels were consumed. [ABSTRACT FROM AUTHOR]

Given the increasing trend of cannabis use for recreational and therapeutic purposes, a comprehensive examination of cannabis effects is warranted. The principal psychoactive constituent of cannabis, △-9-tetrahydrocannabinol (THC), is a potent disrupter of neurodevelopment. Nevertheless, the impact of acute exposure to THC on developing motor systems is not well-investigated. In this study, using a neurophysiological whole cell patch clamp approach we demonstrated that a 30-min exposure to THC can alter spontaneous synaptic activities at neuromuscular junctions of 5-day post-fertilized zebrafish. An increased frequency of synaptic activity and altered decay kinetic properties were documented in the THC-treated larvae. Locomotive behaviors, including swimming activity rate and C-start escape response to sound were also affected by THC. Although the THC-treated larvae displayed hyperactivity of their basal swimming levels, their escape response rate to sound stimuli was reduced. These findings suggest that acute exposure to THC can disrupt neuromuscular transmission and locomotor-driven responses in developing zebrafish. NEW & NOTEWORTHY Acute exposure to THC alters motor neuron-muscle communication and motor behaviors in developing zebrafish. Our neurophysiology data indicated that the properties of spontaneous synaptic activity at neuromuscular junctions, such as decay component of acetylcholine receptors and frequency of synaptic events, were affected by a 30-min exposure to THC. Hyperactivity and reduced responsiveness to the sound stimulus were also observed in the THC-treated larvae. Exposure to THC during early developing stages may induce motor dysfunction. [ABSTRACT FROM AUTHOR]

Zhong, Xin, Wenqiong Du, Zhaowen Zong, Renqing Jiang, Yijun Jia, Zhao Ye, and Haoyang Yang. Features of coagulo-fibrinolytic derangement due to bleeding in nonacclimatized rabbits acutely exposed to high altitude. High Alt Med Biol. 24:68–75, 2023. Background: The present study aimed to observe the time course of coagulo-fibrinolytic derangement due to bleeding in rabbits acutely exposed to high altitude (HA). Materials and Methods: Forty-eight rabbits were randomly divided into four groups and were subjected to minor bleeding at low altitude, major bleeding at low altitude, minor bleeding after acute exposure to HA, and major bleeding after acute exposure to HA. To produce minor and major bleeding, 10% and 30% of the total blood volume was removed, respectively. At designated time points, samples were taken for laboratory examination. Results: While minor bleeding at low altitude led to minor coagulo-fibrinolytic derangements, it led to complicated derangements at HA, which presented as an early hypercoagulable state and transition to hypocoagulable and hyperfibrinolytic states with lower clot firmness. Major bleeding at HA resulted in greater derangements of the R time, K values, the D-dimer concentration, the alpha angle, maximum amplitude, and the concentration of fibrinogen than were observed at low altitude. Conclusions: The extent of coagulo-fibrinolytic derangements due to bleeding in rabbits after acute exposure to HA was more severe and complicated than that at low altitude. Therefore, proper resuscitation should be applied based on these changes. [ABSTRACT FROM AUTHOR]

In present times, the levels of ionizing radiation (IR) on the surface of Earth are relatively low, posing no high challenges for the survival of contemporary life forms. IR derives from natural sources and naturally occurring radioactive materials (NORM), the nuclear industry, medical applications, and as a result of radiation disasters or nuclear tests. In the current review, we discuss modern sources of radioactivity, its direct and indirect effects on different plant species, and the scope of the radiation protection of plants. We present an overview of the molecular mechanisms of radiation responses in plants, which leads to a tempting conjecture of the evolutionary role of IR as a limiting factor for land colonization and plant diversification rates. The hypothesis-driven analysis of available plant genomic data suggests an overall DNA repair gene families' depletion in land plants compared to ancestral groups, which overlaps with a decrease in levels of radiation exposure on the surface of Earth millions of years ago. The potential contribution of chronic IR as an evolutionary factor in combination with other environmental factors is discussed. [ABSTRACT FROM AUTHOR]

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Although numerous ecotoxicological assessments of European honeybee (Apis mellifera L.) have been performed, Japanese wild bees are less well studied in this regard. To address this knowledge gap, we assessed the mortality and acute toxicity (LD50) of 3 common agricultural insecticides (clothianidin, fipronil, and diazinon) on as many as 6 species of Japanese wild bees (Andrena prostomias Perez, Apis cerana japonica Radoszkowski, Bombus deuteronymus Perez, Bombus honshuensis Tkalcu, Bombus hypocrita Perez, and Eucera spp.; all or any of them). The datasets were obtained via standard acute toxicity testing, with assessment of mortality at 24 and 48 h after exposure to the insecticides. These data provide important information regarding the effects of insecticides on Japanese wild bees and their conservation.

Imidacloprid is a neonicotinoid neurotoxin that remains widely used worldwide and persists in the environment, resulting in chronic exposure to non-target insects. To accurately map dose-dependent effects of such exposure across taxa, toxicological assays need to assess relevant modes of exposure across indicator species. However, due to the difficulty of these experiments, contact bioassays are most frequently used to quantify dose. Here, we developed a novel naturalistic feeding bioassay to precisely measure imidacloprid ingestion and its toxicity for acute and chronic exposure in a dipteran, Eristalis tenax L., an important member of an under-represented pollinator group. Flies which ingested imidacloprid dosages lower than 12.1 ng/mg all showed consistent intake volumes and learned improved feeding efficiency over successive feeding sessions. In contrast, at doses of 12.1 ng/mg and higher flies showed a rapid onset of severe locomotive impairment which prevented them from completing the feeding task. Neither probability of survival nor severe locomotive impairment were significantly higher than the control group until doses of 1.43 ng/mg or higher were reached. We were unable to measure a median lethal dose for acute exposure (72 h) due to flies possessing a relatively high tolerance for imidacloprid. However, with chronic exposure (18 days), mortality went up and an LD50 of 0.41 ng/mg was estimated. Severe locomotive impairment (immobilisation) tended to occur earlier and at lower dosages than lethality, with ED50s of 7.82 ng/mg and 0.17 ng/mg for acute and chronic exposure, respectively. We conclude that adult Eristalis possess a much higher tolerance to this toxin than the honeybees that they mimic. The similarity of the LD50 to other dipterans such as the fruitfly and the housefly suggests that there may be a phylogenetic component to pesticide tolerance that merits further investigation. The absence of obvious adverse effects at sublethal dosages also underscores a need to develop better tools for quantifying animal behaviour to evaluate the impact of insecticides on foraging efficiency in economically important species.

Polypropylene microplastics are the leading contaminant in aquatic environments, although research on their toxicity remains scarce. The proposed research focuses on the harmful consequences of acute exposure to polypropylene microplastics in Daphnia similis. This work converts widely available polypropylene bags into microplastics using xylene. FTIR findings demonstrated the lack of xylene residue in the produced polypropylene microplastic particles, which were spherical and ranged in size from 11.86 to 44.62 µm (FE-SEM). The results indicate that acute exposure to polypropylene microplastics causes immobility in D. similis. Ingestion of microplastics enhances the generation of reactive oxygen species (ROS), as shown by biochemical studies. Due to the production of free radicals in D. similis, the antioxidant enzymes superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx) and glutathione-S-transferase (GST) and a non-antioxidant enzyme of reduced glutathione (GSH) and also oxidative stress effects in lipid (lipid peroxidation — LPO), protein (carbonyl protein — CP) were increased. Additionally, the amount of the neurotransmitter enzyme acetylcholinesterase (AChE) activity was decreased. These findings indicate that the accumulation of polypropylene microplastics in the bodies of filter-feeding organisms should aggravate toxicity in the freshwater environment. [ABSTRACT FROM AUTHOR]

Ionizing radiation (IR) impact cellular and molecular processes that require chromatin remodelling relevant for cellular integrity. However, the cellular implications of ionizing radiation (IR) delivered per time unit (dose rate) are still debated. This study investigates whether the dose rate is relevant for inflicting changes to the epigenome, represented by chromatin accessibility, or whether it is the total dose that is decisive. CBA/CaOlaHsd mice were whole-body exposed to either chronic low dose rate (2.5 mGy/h for 54 d) or the higher dose rates (10 mGy/h for 14 d and 100 mGy/h for 30 h) of gamma radiation (60Co, total dose: 3 Gy). Chromatin accessibility was analysed in liver tissue samples using Assay for Transposase-Accessible Chromatin with high-throughput sequencing (ATAC-Seq), both one day after and over three months post-radiation (>100 d). The results show that the dose rate contributes to radiation-induced epigenomic changes in the liver at both sampling timepoints. Interestingly, chronic low dose rate exposure to a high total dose (3 Gy) did not inflict long-term changes to the epigenome. In contrast to the acute high dose rate given to the same total dose, reduced accessibility at transcriptional start sites (TSS) was identified in genes relevant for the DNA damage response and transcriptional activity. Our findings link dose rate to essential biological mechanisms that could be relevant for understanding long-term changes after ionizing radiation exposure. However, future studies are needed to comprehend the biological consequence of these findings. [ABSTRACT FROM AUTHOR]

Chronically increased levels of high molecular weight advanced glycation end products (HMW-AGEs) are known to induce cardiovascular dysfunction. Whether an acute increase in HMW-AGE levels affects vascular function remains unknown. In this study, we examined whether acute exposure to HMW-AGEs disturbs aortic vasomotor function. Aortae were obtained from healthy male rats and were acutely pre-treated with HMW-AGEs in organ baths. Aortic relaxation responses to cumulative doses of acetylcholine (ACh), in the presence or absence of superoxide dismutase (SOD), were measured after precontraction with phenylephrine (PE). Furthermore, levels of 3-nitrotyrosine were evaluated on aortic paraffine sections. In our study, we show that acute exposure to HMW-AGEs significantly decreases the aortic relaxation response to ACh. SOD pre-treatment prevents acute HMW-AGEs-induced impairment by limiting superoxide formation. In conclusion, our data demonstrate that acute exposure to HMW-AGEs causes adverse vascular remodelling, characterised by disturbed vasomotor function due to increased oxidative stress. These results create opportunities for future research regarding the acute role of HMW-AGEs in cardiovascular dysfunction. [ABSTRACT FROM AUTHOR]

BackgroundEmerging evidence has shown the damage of air pollution and the benefits of physical activity to human health, and the effects of air pollution and physical activity on the nervous system need more research.ObjectiveTo explore the effects of short-term air pollution exposure and physical activity on neural damage biomarkers in healthy elderly.MethodsUsing a design of panel study, physically and mentally healthy retired employees were recruited from Xinxiang Medical University, and were followed up five times regularly from December 2018 to April 2019. The demographic characteristics and physical activity information were obtained by questionnaire, and the weekly physical activity level was calculated according to intensity and duration of physical activity. Biomarkers of neural damage in serum were measured, including brain-derived neurotrophic factor (BDNF), neurofilament light chain (NF-L), neuron specific enolase (NSE), protein gene product 9.5 (PGP9.5), and S100 calcium-binding protein B (S100B). Air pollution data (including PM2.5, PM10, O3, SO2, CO, and NO2) of the follow-up period were collected. Generalized estimation equation was used to analyze the association of air pollution concentration and physical activity level with the concentration of neural damage biomarkers.ResultsA total of 29 volunteers were included in the study, with an average age of (63.5±5.9) years; there were 11 men accounting for 37.93%; more than half of them (62.07%) received above junior middle school education; the mean physical activity level was (80.23±54.51) MET-h·week−1. The daily average concentrations of PM2.5, PM10, O3, SO2, CO, and NO2 during the study period were (68.27±60.98) μg·m−3, (130.57±58.71) μg·m−3, (36.86±13.89) μg·m−3, (17.86±10.59) μg·m−3, (4.94±1.34) mg·m−3, and (50.83±8.03) μg·m−3, respectively. The average serum concentrations of BDNF, NF-L, NSE, PGP9.5, and S100B were (139.12±46.71) μg·L−1, (402.60±183.31) ng·L−1, (11.26±10.32) ng·L−1, (14.32±13.57) ng·L−1, and (127.57±41.74) ng·L−1, respectively. The results of generalized estimation equation showed that a higher concentration of PM2.5 or O3 was associated with increased serum NSE (OR=1.359, 95%CI: 1.224-1.509, P0.05).ConclusionAcute exposure to air pollution and high-level physical activity might affect the neural damage of elderly populations. Specifically, particulate matter (PM2.5) could increase NSE, while gaseous pollutants (O3, NO2, and SO2) could decrease NF-L and PGP9.5.

Among insects, bees are important pollinators, providing many vital ecosystem services. The recent pollinator decline is threatening both their diversity and abundance. One of the main drivers of this decline is the extensive use of pesticides. Neonicotinoids, one of the most popular groups of pesticides, can be toxic to bees. In fact, numerous studies have found that neonicotinoids can cause sublethal effects, which can impair the biology, physiology, and colony survival of the bees. Yet, there are still knowledge gaps, and more research is needed to better understand the interaction between neonicotinoids and bees, especially in the field. A new optical sensor, which can automatically identify flying insects using machine learning, has been created to continuously monitor insect activity in the field. This study investigated the potential use of this sensor as a tool for monitoring the sublethal effects of pesticides on bumblebees. Bombus terrestris workers were orally exposed to field-realistic doses of imidacloprid. Two types of exposures were tested: acute and chronic. The flight activity of pesticide-exposed and non-exposed bumblebees was recorded, and the events of the insect flights recorded by the sensor were used in two ways: to extract the values of the wingbeat frequency and to train machine learning models. The results showed that the trained model was able to recognize differences between the events created by pesticide-exposed bumblebees and the control bumblebees. This study demonstrates the possibility of the optical sensor for use as a tool to monitor bees that have been exposed to sublethal doses of pesticides. The optical sensor can provide data that could be helpful in managing and, ideally, mitigating the decline of pollinators from one of their most major threats, pesticides.

Titanium dioxide is a type of nanoparticle that is composed of one titanium atom and two oxygen atoms. One of its physicochemical activities is photolysis, which produces different reactive oxygen species (ROS). Atya lanipes shrimp affect detrital processing and illustrate the potential importance of diversity and nutrient availability to the rest of the food web. It is essential in removing sediments, which have an important role in preventing eutrophication. This study aimed to determine the toxic effect of changes in behavior and levels of oxidative stress due to exposure to titanium dioxide nanoparticles in Atya lanipes and to determine the effective concentration (EC50) for behavioral variables. The concentrations of TiO2 NPs tested were 0.0, 0.50, 1.0, 2.0, and 3.0 mg/L with the positive controls given 100 µg/L of titanium and 3.0 mg/L of TiO2 NPs ± 100 µg/L of titanium. After 24 h of exposure, significant hypoactivity was documented. The EC50 was determined to be a concentration of 0.14 mg/L. After the exposure to 10 mg/L of TiO2 NPs, oxidative stress in gastrointestinal and nervous tissues was documented. The toxic effects of this emerging aquatic pollutant in acute exposure conditions were characterized by sublethal effects such as behavior changes and oxidative stress.

Water pollution is an increasingly serious problem. Here, Cu and Zn ions were used as stress factors, and G. affinis served as a test organism. Fluorescence quantitative PCR was used to detect changes in the expression of antioxidant genes (SOD, GST, CAT), heat stress genes (Hsp70, Hsp90, Hspd1, Hsc70), and immune system-related genes (IL-1β, IL-8) in G. affinis exposed to Cu and Zn ions over time. To explore the toxic effects of Cu and Zn on G. affinis. The results showed that the 48 h LC50 concentrations of the heavy metals Cu and Zn to G. affinis were 0.17 mg/L and 44.67 mg/L, respectively. Within 48 h, with prolonged Cu exposure, the relative expression levels of the Hsp70, Hsp90, Hspd1, Hsc70, SOD, GST, and CAT genes in the gill tissue first showed a significant increase and then gradually decreased. Gene expression peaked between 9 and 36 h. The relative expression levels of SOD and GST genes in liver tissue showed a gradual decline. Within 48 h, with prolonged Zn exposure, the expression levels of SOD, CAT, and GST genes in G. affinis first increased and then fell before finally rising. The expression levels of IL-1β and IL-8 mRNA showed varying degrees of upward trends, and the expression of IL-8 was the highest for all gill tissue. To sum up, Cu and Zn have strong toxic effects on G. affinis, which makes it possible to use G. affinis as indicator organisms for aquatic environmental pollution.

Zhong, Xin, Zhao Ye, Xiaolin Zhou, Renqing Jiang, Yijun Jia, Wenqiong Du, Haoyang Yang, Lin Zhang, Bai Lu, and Zhaowen Zong. Time course of coagulo-fibrinolytic derangements during acclimatization to high altitude in rabbits and a preliminary study on the possible mechanisms. High Alt Med Biol. 23:240–248, 2022. Background: Conflicting data exist regarding changes in the coagulation system during acclimatization to high altitude (HA), which makes the prevention of thromboembolic events difficult. The present study aimed at observing the dynamic changes in the coagulo-fibrinolysis system during acclimatization to HA and at exploring the possible mechanisms. Materials and Methods: Twenty rabbits of both sexes were randomly divided into two groups, including group A rabbits (healthy plain controls) and group B rabbits (acutely exposed to HA). A traditional coagulation test, thromboelastography analysis, and full blood cell count were used to assess the coagulo-fibrinolytic changes at different time points. Plasma was collected to examine the levels of relevant biomarkers. Results: Six hours and 1 day after acute exposure to HA, the coagulo-fibrinolytic system demonstrated a hypercoagulable state. Further, 3 days after exposure to HA, group B rabbits showed hypocoagulability, increased fibrinolysis, and lower clot firmness and 7 days after exposure to HA, delayed coagulation, decreased fibrinolysis, and increased clot firmness were observed. Subsequently, 14, 21, and 28 days after exposure to HA, we found increased clot firmness. Increased platelet counts and concentrations of fibrinogen and plasminogen activator inhibitor-1 contributed to this change. Conclusion: The coagulo-fibrinolytic derangements during acclimatization to HA in rabbits demonstrated a dynamic pattern. [ABSTRACT FROM AUTHOR]

Rationale: Ultrafine particle (UFP; particles <0.1 μm in diameter) concentrations exhibit high spatiotemporal variability; thus, individual-level exposures and health risks are difficult to estimate. Objectives: To determine the effects of recent UFP exposures on respiratory health outcomes in children and to determine if children with asthma are at increased risk. Methods: Personal sampling of UFPs was completed by adolescents in combination with repeated personal spirometry measurements and ecological momentary assessment of respiratory symptoms (wheeze, cough, and/or shortness of breath). We assessed the association between UFP exposures every 30 minutes up to 150 minutes before measuring forced expiratory volume in 1 second (FEV1), peak expiratory flow, and respiratory symptoms using mixed-effects models and interaction with asthma diagnosis. Results: Participants (N = 105; 43% with asthma) completed an average of 11 spirometry measurements and 16 symptom responses throughout sampling. After adjustments (maternal education, physical activity, season, and distance to nearest roadway), a 10-fold increase in UFP exposure was significantly associated with a 0.04-L decrease (95% confidence interval [CI], -0.07 to -0.001) in FEV1 90 minutes later. Asthma status modified this association in which participants with asthma had significantly lower FEV1 values in response to UFP exposures 30 minutes earlier than participants without asthma. We found a significant increase in the odds of reporting a respiratory symptom 30 minutes after increased UFP exposure (odds ratio, 1.8; 95% CI, 1.00 to 3.00). Conclusions: Greater UFP exposure conferred deleterious effects on lung function and respiratory symptoms within 90 minutes of exposure and was more pronounced among participants with asthma. [ABSTRACT FROM AUTHOR]

Abstract Background There is evidence to suggest that long term exposure to air pollution could be associated with decreased levels of fertility, although there is controversy as to how short term exposure may compromise fertility in IVF patients and what windows of exposure during the IVF process patients could be most vulnerable. Methods This prospective cohort study aimed to evaluate the impact of acute exposure that air pollution have on reproductive outcomes in different moments of the IVF process. Women undergoing IVF living in Barcelona were recruited. Individual air pollution exposures were modelled at their home address 15 and 3 days before embryo transfer (15D and 3D, respectively), the same day of transfer (D0), and 7 days after (D7). The pollutants modelled were: PM2.5 [particulate matter (PM) ≤2.5 μm], PMcoarse (PM between 2.5 and 10μm), PM10 (PM≤10 μm), PM2.5 abs, and NO2 and NOx. Outcomes were analyzed using multi-level regression models, with adjustment for co-pollutants and confouding factors. Two sensitivity analyses were performed. First, the model was adjusted for subacute exposure (received 15 days before ET). The second analysis was based on the first transfer performed on each patient aiming to exclude patients who failed previous transfers. Results One hundred ninety-four women were recruited, contributing with data for 486 embryo transfers. Acute and subacute exposure to PMs showed a tendency in increasing miscarriage rate and reducing clinical pregnancy rate, although results were not statistically significant. The first sensitivity analysis, showed a significant risk of miscarriage for PM2.5 exposure on 3D after adjusting for subacute exposure, and an increased risk of achieving no pregnancy for PM2.5, PMcoarse and PM10 on 3D. The second sensitivity analysis showed a significant risk of miscarriage for PM2.5 exposure on 3D, and a significant risk of achieving no pregnancy for PM2.5, PMcoarse and PM10 particularly on 3D. No association was observed for nitrogen dioxides on reproductive outcomes. Conclusions Exposure to particulate matter has a negative impact on reproductive outcomes in IVF patients. Subacute exposure seems to increase the harmful effect of the acute exposure on miscarriage and pregnancy rates. Nitrogen dioxides do not modify significantly the reproductive success.

Simple Summary: Fish are vulnerable to nitrite stress and display variations in physiologic parameter and stress response. In this study, the effects of nitrite on the stress response of large yellow croaker were evaluated. Large yellow croaker were exposed to four (i.e., 0, 29.36, 58.73, and 88.09 mg/L) nitrite concentrations for 48 h. The results of this study indicated that nitrite exposure could induce oxidative stress in the gills and serum of large yellow croaker. The result of immunoglobulin and lysozyme levels indicated that nitrite exposure could cause an immune response in large yellow croaker. In addition, nitrite stress changed the morphology of the gill of large yellow croaker. Nitrite is a common pollutant in aquaculture water, and nitrite toxicity that negatively affects aquatic species is common in aquaculture systems when the water quality is low. Therefore, the present research aimed to evaluate the effect of acute nitrite exposure on the hematological parameters, antioxidant enzymes, immune response, and gill morphology of large yellow croaker (Larimichthys crocea). The fish were randomly separated and exposed to four (i.e., 0, 29.36, 58.73, and 88.09 mg/L) nitrite concentrations for 48 h. The fish blood and gills were collected at 0, 12, 24, 36, and 48 h of nitrite exposure for further analysis. In hematological parameters, the results showed that the levels of hemoglobin, triglyceride, and total cholesterol in blood significantly decreased (p < 0.05) in all nitrite-treated samples after 12 h, while the contents of methemoglobin in blood significantly increased (p < 0.05) in these treatments. After 48 h of nitrite exposure, the levels of cortisol in serum showed a 94.5%, 132.1%, and 165.6% increase in fish exposed to 29.36, 58.73, and 88.09 mg/L nitrite, respectively. The nitrite (i.e., 29.36, 58.73, and 88.09 mg/L) exposure significantly increased (p < 0.05) the levels of antioxidant enzymes (i.e., catalase and glutathione) in the gill and serum after 12 h of exposure compared with the control. The lysozyme levels in serum decreased in the nitrite (i.e., 29.36, 58.73, and 88.09 mg/L) exposure samples. It was found that immunoglobulin levels in the 29.36, 58.73, and 88.09 mg/L nitrite-treated samples (i.e., 1.86, 1.58, and 0.74 μg/mL, respectively) were lower than that of the control (2.56 μg/mL). In addition, the surface of the gill lamellae displayed deformation and contraction after 48 h of nitrite, especially in the fish exposed to 88.09 mg/L nitrite. These results indicate that the nitrite exposure induced the oxidative stress, affected the immune response, and changed the gill morphology, leading to nitrite poisoning in large yellow croaker. [ABSTRACT FROM AUTHOR]

Acute direct ocular exposure to insecticides is rare and can present as a chemical injury. We present a case of a 21-year-old male patient who had an accidental exposure to chlorpyrifos and propoxur while spraying it as an insecticide. He presented with severe conjunctival ischemia and necrosis involving the inferior fornix. He underwent amniotic membrane transplantation to preserve the ocular surface. The case report highlights the chemical effects of organophosphorus compounds on the ocular surface.

Phthalic acid esters (PAEs) are classified as endocrine disruptors, but it remains unclear if they can enter the marine food-web and result in severe health effects for organisms. Loggerhead turtles (Caretta caretta) can be chronically exposed to PAEs by ingesting plastic debris, but no information is available about PAEs levels in blood, and how these concentrations are related to diet during different life stages. This paper investigated, for the first time, six PAEs in blood of 18 wild-caught Mediterranean loggerhead turtles throughout solid-phase extraction coupled with gas chromatography-ion trap/mass spectrometry. Stable isotope analyses of carbon and nitrogen were also performed to assess the resource use pattern of loggerhead turtles. DEHP (12–63 ng mL-1) and DBP (6–57 ng mL-1) were the most frequently represented PAEs, followed by DiBP, DMP, DEP and DOP. The total PAEs concentration was highest in three turtles (124–260 ng mL-1) whereas three other turtles had concentrations below the detection limit. PAEs were clustered in three groups according to concentration in all samples: DEHP in the first group, DBP, DEP, and DiBP in the second group, and DOP and DMP in the third group. The total phthalates concentration did not differ between large-sized (96.3 ± 86.0 ng mL-1) and small-sized (67.1 ± 34.2 ng mL-1) turtles (p

Cystic fibrosis (CF) is a lethal and widespread autosomal recessive disorder affecting over 80,000 people worldwide. It is caused by mutations of the CFTR gene, which encodes an epithelial anion channel. CF is characterized by a great phenotypic variability which is currently not fully understood. Although CF is genetically determined, the course of the disease might also depend on multiple other factors. Air pollution, whose effects on health and contribution to respiratory diseases are well established, is one environmental factor suspected to modulate the disease severity and influence the lung phenotype of CF patients. This is of particular interest as pulmonary failure is the primary cause of death in CF. The present review discusses current knowledge on the impact of air pollution on CF pathogenesis and aims to explore the underlying cellular and biological mechanisms involved in these effects.

Introduction. Shellfish poisoning could be caused by ingestion of shellfish contaminated by bacteria, viruses, heavy metals, pesticides, marine biotoxins etc. The objective of the study was to determine the theoretical human exposure to shellfish toxins of Bulgarian consumers. The incidence of registered cases of intoxications due to marine biotoxins ingestion – “Toxic effect: Other fish and shellfish poisoning (T61.2)” in regional hospitals was investigated. Materials and methods. Acute exposure (AE), chronic exposure (CE) and hazard quotient (HQ) are calculated based on experimentally-determined levels of shellfish toxins in mussels harvested from North Bulgarian coast in the period 2012 – 2018. We performed a retrospective analysis of the frequency of the diagnosis T61.2, based on medical documentation for the period 1.05.2012 – 7.12.2018 in hospitals in Varna and Dobrich, Bulgaria. Results. Shellfish toxins that most often occur in mussels are domoic acid (DA), yessotoxin (YTX) and pectenotoxin-2 (PTX2). The calculated maximum AE was 1.00 mg/kg bw for DA, 0.02 mg/kg bw for YTX and 0.0045 mg/kg bw for PTX2, respectively. Maximum CE for DA was 0.01 mg/kg bw/day. All estimated values were much lower than those legislated by European Food Safety Authority thresholds. The exposure to marine biotoxins was estimated based on contamination data of mussels harvested from the same region. The analysis for the whole period showed that its frequency is lower than 1%. Clinicians report that this diagnosis is presumptive, based on recent ingestion of shellfish and presence of symptoms consistent with shellfish poisoning. Conclusions. Estimated theoretical acute and chronic exposures agree upon the incidence of clinical cases with the studied diagnosis. A parallel investigation on a prolonged period is required, to increase the accuracy of these results.

Organisms are generally exposed to target contaminant with stable concentrations in traditional ecotoxicological studies. However, it is difficult to truly represent the dynamics and complexity of actual aquatic pollution for risk management. Contaminants may enter nearby aquatic systems in pulsed exposure, thus resulting in that aquatic organisms will be exposed to contaminants at fluctuating concentrations. Especially during the season of summer, due to the changes in displacement or periodic emissions of veterinary antibiotics in aquaculture, algal blooms occur frequently in surrounding waters, thus leading to eutrophication of the water. Florfenicol (FFC) is currently widely used as a veterinary antibiotic, but the aquatic ecological risks of FFC under concentration fluctuations are still unknown. Therefore, the acute exposure, chronic exposure and pulsed exposure effects of FFC on Microcystis aeruginosa were investigated to comprehensively evaluate the ecological risk of FFC and raise awareness of the pulsed exposure mode. Results indicated that the toxic effects of FFC on M. aeruginosa were dominated by exposure mode, exposure duration, exposure frequency, and exposure concentration. The maximum growth inhibition rate of the 10 μg/L FFC treatment amounted to 4.07% during chronic exposure of 18 days. However, the growth inhibition rate decreased from 55.1% to 19.31% when algae was exposure to 10 μg/L FFC during the first pulsed exposure (8 h). Therefore, when the concentration of FFC was equal under chronic and pulsed exposure, FFC exhibited greater toxicity on M. aeruginosa in short pulsed exposure than in continuous exposure. In addition, repetitive pulsed exposure strengthened the resistance of M. aeruginosa on FFC. The adaptive regulation of algae was related to the duration and frequency of exposure. Above results suggested that traditional toxicity assessments lacked consideration for fluctuating concentrations during pollutant emissions, thus underestimating the environmental risk of contaminant. This investigation aims to facilitate the standardization of pulsed exposure. [Display omitted] • Traditional toxicity assessment overlook fluctuations in pollutant concentrations. • Florfenicol (FFC) is more toxic in pulsed exposure than in continuous exposure. • Alga develop resistance to FFC after chronic exposure and repeated pulse exposure. • Algal self-regulation ability is related to the duration and frequency of exposure. [ABSTRACT FROM AUTHOR]

Nanoparticles (NPs) have become an important part of everyday life, including their application in dentistry. Aside from their undoubted benefits, questions regarding their risk to human health, and/or genome have arisen. However, studies concerning cytogenetic effects are completely absent. A group of women acutely exposed to an aerosol released during dental nanocomposite grinding was sampled before and after the work. Exposure monitoring including nano (PM0.1) and respirable (PM4) fractions was performed. Whole-chromosome painting for autosomes #1, #4, and gonosome X was applied to estimate the pattern of cytogenetic damage including structural and numerical alterations. The results show stable genomic frequency of translocations (F G /100), in contrast to a significant 37.8% (p <0.05) increase of numerical aberrations caused by monosomies (p <0.05), but not trisomies. Monosomies were mostly observed for chromosome X. In conclusion, exposure to nanocomposites in stomatology may lead to an increase in numerical aberrations which can be dangerous for dividing cells. • The risk of acute exposure to NPs from dental nanocomposites was studied in women. • Structural and numerical alterations in autosomes and the gonosome were analyzed. • An increase of aneuploidies, but no effect on structural aberrations was observed. • Monosomies in chromosome X were significantly increased. • The risk of exposure for mitotic spindle failure in dividing cells was suggested. [ABSTRACT FROM AUTHOR]

In present times, the levels of ionizing radiation (IR) on the surface of Earth are relatively low, posing no high challenges for the survival of contemporary life forms. IR derives from natural sources and naturally occurring radioactive materials (NORM), the nuclear industry, medical applications, and as a result of radiation disasters or nuclear tests. In the current review, we discuss modern sources of radioactivity, its direct and indirect effects on different plant species, and the scope of the radiation protection of plants. We present an overview of the molecular mechanisms of radiation responses in plants, which leads to a tempting conjecture of the evolutionary role of IR as a limiting factor for land colonization and plant diversification rates. The hypothesis-driven analysis of available plant genomic data suggests an overall DNA repair gene families’ depletion in land plants compared to ancestral groups, which overlaps with a decrease in levels of radiation exposure on the surface of Earth millions of years ago. The potential contribution of chronic IR as an evolutionary factor in combination with other environmental factors is discussed.

Inhalation exposures to nanoparticles (NPs) from printers and photocopiers have been associated with upper airway and systemic inflammation, increased blood pressure, and cases of autoimmune and respiratory disorders. In this study we investigate oxidative stress induced by exposures to copier-emitted nanoparticles using a panel of urinary oxidative stress (OS) biomarkers representing DNA damage (8-hydroxydeoxyguanosine, 8-OHdG; 8-hydroxyguanosine, 8-OHG; 5-hydroxymethyl uracil 5-OHMeU), lipid peroxidation (8-isoprostane; 4-hydroxynonenal, HNE), and protein oxidation biomarkers (o-tyrosine, 3-chlorotyrosine, and 3-nitrotyrosine) under conditions of acute (single 6 h exposure, 9 volunteers, 110 urine samples) and chronic exposures (6 workers, 11 controls, 81 urine samples). Urinary biomarkers were quantified with liquid chromatography–tandem mass spectrometry after solid phase extraction sample cleanup. 8-OHdG, 8-OHG, 8-isoprostane, and HNE were significantly elevated in both the acute and chronic exposure study participants relative to the controls. In the acute exposure study, the geometric mean ratios post-/pre-exposure were 1.42, 1.10, 2.0, and 2.25, respectively. Urinary 8-OHG and HNE increased with time to at least 36 h post-exposure (post-/pre-exposure GM ratios increased to 3.94 and 2.33, respectively), suggesting slower generation and/or urinary excretion kinetics for these biomarkers. In chronically exposed operators, the GM ratios of urinary biomarkers relative to controls ranged from 1.52 to 2.94, depending on the biomarker. O-Tyrosine and 5-OHMeU biomarkers were not significantly different from the controls. 3-chlorotyrosine and 3-nitrotyrosine were not detected in the urine samples. We conclude that NPs from photocopiers induce systemic oxidative stress by damaging DNA, RNA, and lipids. Urinary levels of 8-OHdG, 8-OHG, HNE, and 8-isoprostane were orders of magnitude higher than in nanocomposite processing workers, comparable to nano titanium dioxide and fiberglass manufacturing workers, but much lower than in shipyard welding and carbon nanotube synthesis workers. Biomarkers 8-OHdG, 8-OHG, 8-isoprostane, and HNE appear to be more sensitive and robust urinary biomarkers for monitoring oxidative stress to NPs from photocopiers. [ABSTRACT FROM AUTHOR]

The toxicity of the bipyridine cationic herbicide paraquat (PQ) to the lung and kidneys has been widely documented, but the acute toxic effects of PQ on the nervous system have received little attention. This study aimed to explore the changes in the phenotypic differentiation of microglia in rats caused by acute PQ exposure. As results, acute PQ exposure induced pyknosis, edema, and apoptosis in substantia nigra neurons. Immunohistochemistry and western blotting showed that, on day 18, with the increase of exposure dose, the number of Iba-1-positive cells presented an increasing trend with no statistically significant difference among the groups (P > 0.05). Compared with the control group, the process length of Iba-1-positive cells decreased of acute 25 mg/kg PQ exposure on day 18 (P < 0.05). Compared with the control group, on day 39, the number of Iba-1-positive cells in the SN decreased of acute 25 mg/kg PQ exposure, while that increased of acute 45 mg/kg PQ exposure (P < 0.05). The number of endpoints decreased of acute 25 mg/kg PQ exposure (P < 0.05). The process length became shorter both of acute 25 mg/kg and 45 mg/kg PQ exposure (P < 0.05). On day 69, compared with the control group, the number of Iba-1-positive cells in the SN significantly increased of acute 45 mg/kg PQ exposure (P < 0.05). The number of endpoints increased and the process length became longer of acute 25 mg/kg PQ exposure (P < 0.05). Then, the mean fluorescence intensity of inducible nitric oxide synthase (iNOS) and arginine 1 (ARG1) was compared. The number of the M1 phenotype of microglia increased during the early stage of acute 25 mg/kg PQ exposure, whereas the number of the M2 phenotype of microglia increased during the early stage of acute 45 mg/kg PQ exposure (P < 0.05). On day 39, compared with the control group, the expression of iNOS in the SN of acute 45 mg/kg PQ exposure increased than of acute 25 mg/kg exposure. The expression of Arg-1 of 25 mg/kg PQ exposure was significantly increased (P < 0.05). On day 69, the expression of iNOS and ARG1 increased in the 25 and 45 mg/kg PQ exposure groups. In summary, changes in microglia phenotypic differentiation were related to exposure dose and exposure time (P < 0.05). [ABSTRACT FROM AUTHOR]