Mixture Of Pollutants Research Articles

Joint effects of per- and polyfluoroalkyl substance alternatives and heavy metals on renal health: A community-based population study in China

BackgroundPrevious studies have indicated that chlorinated polyfluorinated ether sulfonic acids (Cl-PFESAs), when used as an alternative to per- and polyfluoroalkyl substances (PFASs), result in kidney toxicity. However, their co-exposure with heavy metals, has not yet been described. ObjectivesTo explore the joint effects of Cl-PFESAs and heavy metal exposure on renal health in Chinese adults, and identify specific pollutants driving the associations. MethodsOur sample consists of 1312 adults from a cross-sectional survey of general communities in Guangzhou, China. We measured Cl-PFESAs, legacy PFASs (perfluorooctanoic acid [PFOA] and perfluorooctane sulfonated [PFOS]), and heavy metals (arsenic, cadmium, and lead). The relationship between single pollutant and glomerular filtration rate (eGFR) and the odds ratio (OR) of chronic kidney disease (CKD) was studied using Generalized additive models (GAMs). Bayesian Kernel Machine Regression (BKMR) models were applied to assess joint effects of Cl-PFESAs and heavy metals. Additionally, we conducted a sex-specific analysis to determine the modification effect of this variable. ResultsIn single pollutant models, CI-PFESAs, PFOA, PFOS and arsenic were negatively associated with eGFR. Additionally, PFOA and heavy metals were positively correlated with the OR of CKD. For example, the estimated change with 95% confidence intervals (CI) of eGFR at from the highest quantile of 6:2 Cl-PFESA versus the lowest quantile was −5.65 ng/mL (95% CI: −8.21, −3.10). Sex played a role in modifying the association between 8:2 Cl-PFESA, PFOS and eGFR. In BKMR models, pollutant mixtures had a negative joint association with eGFR and a positive joint effect on CKD, especially in women. Arsenic appeared to be the primary contributing pollutant. ConclusionWe provide epidemiological evidence that Cl-PFESAs independently and jointly with heavy metals impaired kidney health. More population-based human and animal studies are needed to confirm our results.

Differential cardiopulmonary effects of isoprene-versus toluene-generated photochemically-Aged smog in rats

Photochemical smog is a complex mixture of primary and secondary air pollutants including secondary organic aerosols (SOA), ozone and reactive aldehydes which has been linked to increased risk of adverse cardiovascular and pulmonary responses. The components and related health effects of smog are thought to be determined both by the precursor chemicals and reaction conditions. Here we examined the difference between isoprene- (IS-) and toluene- (TL) generated smog in causing cardiopulmonary effects in rats. Wistar-Kyoto rats were exposed to either filtered air (FA) or smog for 4 h. IS-smog contained 660 ppb NO2, 335 ppb O3, and 178 μg/m3 SOA while TL-smog had 380 ppb NO2, 250 ppb O3, and 1,250 μg/m3 SOA. Whole-body plethysmography was performed at baseline and after each exposure and left ventricular function was measured using a Millar probe and arrhythmic sensitivity to aconitine. Tidal volume decreased only after IS-smog while inspiratory time and nasal injury increased following both smog atmospheres. Only TL-smog caused an increase in PenH, which is an indicator of airway irritation. On the other hand, only IS-smog caused left ventricular pressure to decrease, while only TL-smog increased sensitivity to cardiac arrhythmia. These data indicate that the source of smog atmosphere plays a large role in the types of responses it elicits and that its relative SOA and gaseous composition determine the extent of cardiovascular versus respiratory effects.

Adverse effects of ambient fine particulate matter (PM2.5 ) on vascular smooth muscle cells.

Cardiovascular diseases are the leading cause of death worldwide. Meanwhile, environment air pollution has become a serious health risk factor, contributing to the mortality of respiratory and cardiovascular diseases. A substantial body of evidence has shown that many types of vascular diseases are related to air pollution. The physiology and pathophysiology of the three layers of vascular vessels, especially the inner and medial layer, contribute to the process of vascular diseases. Vascular smooth muscle cells (VSMCs) are the predominant cells in the medial layer, and several studies have indicated that air pollution has an adverse effect on VSMCs. There are numerous sources of air pollution across the world, and the components of air pollutants are a complex mixture of gaseous pollutants and particulate matter. Among these air pollutants, particulate matter (PM)2.5 presents the highest risk factor leading to global mortality from cardiovascular disease and disability. In this review, we primarily focus on the impacts of PM2.5 exposure on VSMCs. We further discuss the correlation between exposure to PM2.5 and other vascular diseases and present potential protective and treatment strategies to decrease vascular mortality related to air pollution.

The skin is no barrier to mixtures: Air pollutant mixtures and reported psoriasis or eczema in the Personalized Environment and Genes Study (PEGS)

BackgroundAutoimmune (AI) diseases appear to be a product of genetic predisposition and environmental triggers. Disruption of the skin barrier causes exacerbation of psoriasis/eczema. Oxidative stress is a mechanistic pathway for pathogenesis of the disease and is also a primary mechanism for the detrimental effects of air pollution.MethodsWe evaluated the association between autoimmune skin diseases (psoriasis or eczema) and air pollutant mixtures in 9060 subjects from the Personalized Environment and Genes Study (PEGS) cohort. Pollutant exposure data on six criteria air pollutants are publicly available from the Center for Air, Climate, and Energy Solutions and the Atmospheric Composition Analysis Group. For increased spatial resolution, we included spatially cumulative exposure to volatile organic compounds from sites in the United States Environmental Protection Agency Toxic Release Inventory and the density of major roads within a 5 km radius of a participant’s address from the United States Geological Survey. We applied logistic regression with quantile g-computation, adjusting for age, sex, diagnosis with an autoimmune disease in family or self, and smoking history to evaluate the relationship between self-reported diagnosis of an AI skin condition and air pollution mixtures.ResultsOnly one air pollution variable, sulfate, was significant individually (OR = 1.06, p = 3.99E−2); however, the conditional odds ratio for the combined mixture components of PM2.5 (black carbon, sulfate, sea salt, and soil), CO, SO2, benzene, toluene, and ethylbenzene is 1.10 (p-value = 5.4E−3).SignificanceWhile the etiology of autoimmune skin disorders is not clear, this study provides evidence that air pollutants are associated with an increased prevalence of these disorders. The results provide further evidence of potential health impacts of air pollution exposures on life-altering diseases.Significance and impact statementThe impact of air pollution on non-pulmonary and cardiovascular diseases is understudied and under-reported. We find that air pollution significantly increased the odds of psoriasis or eczema in our cohort and the magnitude is comparable to the risk associated with smoking exposure. Autoimmune diseases like psoriasis and eczema are likely impacted by air pollution, particularly complex mixtures and our study underscores the importance of quantifying air pollution-associated risks in autoimmune disease.

Study of Photocatalytic Degradation and Simultaneous Removal of a Mixture of Pollutant (MB and MG) Dyes: Kinetic and Adsorption Isotherm

Background: The major challenges faced by developing countries are the issues associated with various pollutants, such as dyes, pesticides, heavy metals, etc. Various materials and methods are available for the removal of these pollutants. Major research works have been performed on single pollutants, and rarely any research literature is available for a mixture of pollutants. This is one of the major reasons to carry out our research work in this field. Objectives: This study aimed to develop an efficient ZnO/GO nanocomposite as a photocatalyst, characterize it by PXRD, FT-IR, and TGA, and evaluate its catalytic activity by degradation of MG, MB and a mixture of both Methods: In this study, GO was synthesized by the modified Hummers method. In this method, graphite powder was mixed with sulphuric acid and NaNO3. Then KMnO4 solution was added under continuous stirring. Excess KMnO4 was removed by H2O2 and the colour of the solution turned to be dark yellow. After proper washing and maintaining pH, the resulting material was dried at 60°C for 12h to obtain GO. GO was dispersed in ethanol, and 0.387g Zn(CH3COO)2.2H2O was added to it. The resulting mixture was sonicated, and a solution of NH3 was added very slowly by maintaining the pH of the solution at ~7. The resulting product was dried at 80°C and then calcined at 500 °C for 2.5 h to get ZnO/GO nanocomposite. Results: The photodegradation of MG, MB and a mixture of MG and MB was found to be 92.23%, 35.96%, and 66.22%, respectively, in 4−5 h. The degradation of the dyes was found to follow Second-order kinetics with a multilayer absorption phenomenon. Conclusion: MB showed less degradation as compared to MG, but its photocatalytic activity enhanced after adding MG. This ZnO/GO nanocomposite seems to be a potential candidate to address the challenges associated with multi-pollutants, such as dyes.

Toxic effects and primary source of the aged micro-sized artificial turf fragments and rubber particles: Comparative studies on laboratory photoaging and actual field sampling

Numerous micro-sized artificial turf fragments (MATF) and rubber particles (MRP) are generated and accumulated during the use of the artificial playing field. However, attention has rarely been paid to the potential toxic effects of MATF and MRP on sportsmen. In this study, the active components and chemical composition of aged MATF and MRP derived from laboratory photoaging and actual field sampling were detected, and their effects on cytotoxicity were examined correspondingly. Laboratory photoaging significantly increased environmental persistent free radicals (EPFRs), reactive oxygen species (ROS) abundances and oxidative potential (OP) levels on MATF and MRP, but they have limited cytotoxicity. Unfortunately, in the actual field, aged MATF and MRP with higher heavy metals and polycyclic aromatic hydrocarbons (PAHs) contents exhibited markedly higher cytotoxicity with the survival rate of cells of 78 % and 26 % (p < 0.05), although they had lower EPFRs and ROS yields. Correlation analysis revealed that the cell viability was closely linked to heavy metals of MATF (p < 0.05), and to organic hydroperoxide (OHP), PAHs and heavy metals of MRP (p < 0.05). By systematically considering the above results, heavy metals and PAHs enriched on MATF and MRP from the surrounding environment played the important role in the cytotoxicity, which was different from conventional perspectives. Our findings demonstrate that MATF and MRP associated with an artificial turf field contain potent mixtures of pollutants and can, therefore, be relevant yet underestimated factors contributing to the health risks.

Synthesis of porous materials by the modification of coal fly ash and its environmentally friendly use for the removal of heavy metals from wastewater

Wastewater is a complex mixture of many pollutants, where the high-risk pollutants are heavy metals (HMs) in industrial wastewater due to their difficult removal. In this study, the waste CFA was used as the main raw material for production of new innovated flocculants porous particles by modification of coal fly ash (CFA) using a multi-step base–acid–base (NaOH–HCl–NaOH) modification method. The morphological structure and elemental composition of the prepared MCFA were analyzed through characterization analysis, i.e., SEM, EDX, FT-IR, BET, XPS, and XRD. Results found that the surface area of the flocculant particles of MCFA was increased from 5.241 to 32.011 m2/g, which increased the adsorption process of HMs (Mn2+, Cu2+, Ni2+, and Pb2+). The maximum removal efficiencies (Re %) of MCFA for Mn2+, Cu2+, Ni2+, and Pb2+ were recorded at 94.26%, 95.88%, 71.04%, and 99.91%, respectively. The Freundlich isotherm model was fitted for the adsorption process, and the maximum adsorption amounts of MCFA for Mn2+, Cu2+, Ni2+, and Pb2+ were 558.9219, 0.4341, 210.9737, and 12.1957 mg/g, respectively. Moreover, the kinetic model indicated that physicochemical adsorption occurred between the adsorbate materials and the adsorbent.

Continuous flow synthesis of disordered covalent organic framework for ultra-high removal of industrial pollutants in flow

Covalent organic frameworks (COF) are increasingly gaining attention as adsorbents for industrial pollutants due to their high surface area and ordered porosity. However, often they have low removal efficiency due to the limited access to their pores. Approachability of foreign molecules to active sites within the framework can be maximized by pore engineering and introduction of defects. Here, we report the synthesis of an imine-based COF (DAB-TFP) at ambient conditions with the incorporation of disorder using continuous flow for the first time. A reusable microreactor that was fabricated using a cost-effective scaffolding technique was used for the flow reactions. The disorder in the COF increased accessibility of its surface for foreign molecules. Moreover, the disorder within the COF resulted in accelerated adsorption of methylene blue (MB) in continuous flow. The removal efficiency of the COF for MB was three folds higher during in-situ adsorption in continuous flow than the traditional batch mode of adsorption. The COF could be regenerated and recycled in continuous flow without any significant loss in the activity. Further, almost 100 % of MB could be reclaimed. The COF was also able to efficiently adsorb a mixture of pollutants as well as a simulated textile industrial waste. Hence, the reported method is a green and sustainable approach for industrial effluent treatment.

Using a Pollution-to-Risk Method to Evaluate the Impact of a Cold Front: A Case Study in a Downstream Region in Southeastern China

Cold fronts frequently intrude China in winter, causing air pollution episodes in downwind regions. Fine particulate matter (PM2.5) has been used as a major proxy of air pollution to examine the impacts of cold fronts. Compared to particles, gaseous pollutants can cause comparable or even higher levels of short-term health risks. In this study, a pollution-to-risk model was used to systematically evaluate the impacts of cold fronts on the combined health risks of air pollution mixtures, including PM2.5, nitrogen dioxide (NO2), ozone (O3), and sulfur dioxide (SO2). Dominant pollutants that caused significant mortality risks during a cold frontal passage in December 2019 over Fuzhou, a downwind city in southeastern China, were then examined. Under northerly frontal airflows, a pollution belt propagated southwards. In Fuzhou, two pollution peaks existed during the cold frontal passage. At the first peak, convergence and stagnant air in the frontal zone rapidly accumulated local air pollutants. The dominant pollutants that caused the mortality risk were identified as NO2 and PM2.5, both of which contributed 45% to the total risk. At the second peak, advection transported a significant amount of secondary pollutants from the upwind regions. Although PM2.5 was the dominant pollutant at this peak, gaseous pollutants still accounted for 34% of the total risk. Our risk analyses underscore the significant health impacts of gaseous pollutants during cold frontal passages in winter. The results generated from this study will help guide environmental policy makers in forming and improving air pollution control strategies during pollution episodes.

Assessment of diesel exhaust pollutants effects in Tillandsia capillaris and Ramalina celastri by laboratory trials

Traffic-related air pollution is one of the most relevant environmental problems in urban areas. Several cryptogams (i.e., lichens and mosses) and vascular species have been employed to monitor urban air pollution since they allow the assessment of air quality in a large number of sampling sites simultaneously at low cost. In large urban cities, vehicle emissions are frequently the major source of air pollution along with residential energy (for cooking and heating), industry, power generation, and waste incineration. Biomonitors in these urban environments are exposed to a mixture of pollutants making it difficult to identify which pollutant causes the greatest damage to organisms. However, studies that analyze the effect of pollutants emitted by vehicle exhaust are scarce and in the particular case of the most used biomonitor species in Argentina, no analysis of how they are affected by vehicle emissions has been carried out so far. So, the aim of this work was to analyze changes in physiochemical parameters (pigment content, pro-oxidant products, and sulfur accumulation) in Ramalina celastri, and heavy metal accumulation in Tillandsia capillaris, exposed to diesel exhausts under laboratory conditions. A strong damage in the photosynthetic apparatus of R. celastri was observed as well as metal concentration in T. capillaris after 20 min of exposure and 48 h of permanence in the exposure chambers. The results indicate that not only the particles and metals cause damage to these two well-known biomonitors, but the interaction of these pollutants with other components of the atmosphere that form different secondary pollutants, together with a longer exposure time, could cause the highest level of damage in them.

Impact of mixtures of persistent organic pollutants on breast cancer aggressiveness

IntroductionBreast cancer (BC) is frequent with a poor prognosis in case of metastasis. The role of the environment has been poorly evaluated in its progression. We searched to assess whether a mixture of pollutants could be responsible of BC aggressiveness. MethodsPatients undergoing surgery for their BC were prospectively included in the METAPOP cohort. Forty-two POPs were extracted, among them 17 dioxins (PCDD/F), 16 polychlorobiphenyls (PCB), 8 polybromodiphenylethers (PBDE) and 2,2′,4,4′,5,5′-hexabromobiphenyl (PBB153) were measured in the adipose tissue surrounding the tumor. BC aggressiveness was defined using tumor size and metastasis (distant or lymph nodes). Two complementary models were used to evaluate the impact of the mixture of pollutants: the BKMR (Bayesian Kernel machine regression) and WQS (weighted quantile sum regression) models. The WQS estimates the weight (positive or negative) of a certain chemical based on its quantile and the BKMR model applies a kernel-based approach to estimate posterior inclusion probabilities. The sub-group of patients with a body mass index (BMI) > 22 kg/ m2 was also analyzed. ResultsNinety-one patients were included. Of these, 38 patients presented a metastasis, and the mean tumor size was 25.4 mm. The mean BMI was 24.5 kg/m2 (+/- 4.1). No statistical association was found in the general population. However, in patients with a BMI > 22 kg/ m2, our mixture was positively associated with tumor size (OR: 9.73 95 %CI: 1.30–18.15) and metastasis (OR = 3.98 95 %CI = 1.09–17.53) using the WQS model. Moreover, using the BKMR model on chemical families, dioxin like chemicals and PCDD were associated with a higher risk of metastasis. DiscussionThese novel findings identified a mixture associated with breast cancer aggressiveness in patients with a BMI > 22 kg/ m2.

Exposure to persistent organic pollutants alters the serum metabolome in non-obese diabetic mice

IntroductionAutoimmune disorders such as type 1 diabetes (T1D) are believed to be caused by the interplay between several genetic and environmental factors. Elucidation of the role of environmental factors in metabolic and immune dysfunction leading to autoimmune disease is not yet well characterized.ObjectivesHere we investigated the impact of exposure to a mixture of persistent organic pollutants (POPs) on the metabolome in non-obese diabetic (NOD) mice, an experimental model of T1D. The mixture contained organochlorides, organobromides, and per- and polyfluoroalkyl substances (PFAS).MethodsAnalysis of molecular lipids (lipidomics) and bile acids in serum samples was performed by UPLC-Q-TOF/MS, while polar metabolites were analyzed by GC-Q-TOF/MS.ResultsExperimental exposure to the POP mixture in these mice led to several metabolic changes, which were similar to those previously reported as associated with PFAS exposure, as well as risk of T1D in human studies. This included an increase in the levels of sugar derivatives, triacylglycerols and lithocholic acid, and a decrease in long chain fatty acids and several lipid classes, including phosphatidylcholines, lysophosphatidylcholines and sphingomyelins.ConclusionTaken together, our study demonstrates that exposure to POPs results in an altered metabolic signature previously associated with autoimmunity.

Genetic toxicology in hygiene

The article discusses the directions of research in the field of genetic toxicology, which allow solving problems important for hygiene, aimed at ensuring the genetic health of the population. The main areas of research are: assessment of the genetic hazard of environmental factors and the level of pollution by genotoxicants; analysis of the total mutagenic activity of mixtures of chemical pollutants; control over mutational events in the somatic cells of people working in hazardous production conditions, which is necessary to improve the prevention, diagnosis and treatment of occupational diseases and multifactorial pathology; study of individual genetically determined human sensitivity to the impacts of adverse environmental factors in order to improve professional selection and development of personalized preventive medicine; assessment of mutagenicity in short-term tests to predict the carcinogenicity of the studied substances; search for antimutagens. The methods used in genetic toxicology are described. The main directions and results of the work of the Department of Genetic Toxicology of the FBES “Federal Scientific Center of Hygiene named after F.F. Erisman” of the Rospotrebnadzor are given. Conclusion. The results of genotoxicological studies allow us to evaluate and establish hazard classes of the tested substances, predict possible long-term effects. Monitoring of mutational events in the somatic cells of people exposed to various environmental factors, assessment of individual human sensitivity to specific factors or their combinations make it possible to identify and evaluate potentially dangerous factors for genetic health, develop preventive measures and carry out reasonable professional selection of persons to work in harmful production conditions.

Variation of the toxicity caused by key contaminants in industrial wastewater along the treatment train of Fenton-activated sludge-advanced oxidation processes

Industrial wastewater contains a mixture of refractory and hazardous pollutants that have comprehensive toxic effects. We investigated the treatment of a long-chain industrial wastewater treatment train containing Fenton, biological anoxic/oxic (AO), and heterogeneous ozone catalytic oxidation (HOCO) processes, and evaluated their detoxification effect based on the analysis of the genic toxicity of some key contaminants. The results showed that although the effluent met the discharge standard in terms of traditional quality parameters, the long-chain treatment process could not effectively detoxify the industrial wastewater. The analysis results of summer samples showed that the Fenton process increased the total toxicity and genotoxicity of the organics, concerned metals, and non-volatile pollutants, whereas the A/O process increased the toxicity of the organics and non-volatile pollutants, and the HOCO process led to higher toxicity caused by metals and non-volatile pollutants. The outputs of the winter samples indicated that the Fenton process reduced the total toxicity and genotoxicity caused by non-volatile pollutants but increased that of the organics and concerned metals. The effect of the A/O process on the effluent toxicity in winter was the same as that in summer, whereas the HOCO process increased the total toxicity and genotoxicity of the metals in winter samples. Correlation analysis showed that various toxicity stresses were significantly correlated with the variation of these key pollutants in wastewater. Our results could provide a reference for the optimization of industrial wastewater treatment plants (IWTPs) by selecting more suitable treatment procedures to reduce the toxicity of different contaminants.

Fabrication and performance evaluation of tannin iron complex (TA-FeIII/PES) UF membrane in treatment of BTEX wastewater

Oil exploration generates produced water that is characterized as hazardous and toxic waste. Produced water contains a mixture of various pollutants, including monoaromatic hydrocarbons BTEX (benzene, toluene, ethylbenzene, and xylene), compounds that are carcinogenic even in small concentrations. In this study, tannin iron complex (TA-FeIII), blended into polyethersulfone (PES) membrane was evaluated for the treatment of BTEX-containing wastewater. The membranes were fabricated using the non-solvent induced phase separation (NIPS) method and loading of the TA-FeIII complex on the membranes varied from 0–0.9 wt%. The fabricated membranes were characterized using various techniques such as scanning electron microscopy (SEM), water contact angle (WCA), Fourier transform infrared (FTIR) spectroscopy, and atomic force microscopy (AFM) to check the surface morphology, hydrophilicity, surface functionality and surface roughness of the fabricated membranes, respectively. The TA-FeIII modified membranes showed increased pure water flux from 100 (PES 0) to ∼150 (PES 0.9) L/(m2‧h) at 100 kPa. The performance of the fabricated membranes was tested using 70 mg/L synthetic BTEX solution. Overall BTEX rejection &gt; 70% was achieved at increasing TA-FeIII loadings compared to BTEX rejection &lt; 65% for the pure PES membrane. Rejection of the BTEX compounds was mainly through the size exclusion mechanism. These modified TA-FeIII/PES UF membranes proved to be effective in the treatment of BTEX-containing water, and also have the potential to be applied in oily wastewater treatment.

Net effect of air pollution controls on health risk in the Beijing–Tianjin–Hebei region during the 2022 winter Olympics and Paralympics

Due to the non-linearity in ozone (O3) formation, reducing the emission of nitrogen oxides (NOx) may increase O3 concentration. Given the counteractive O3 response to NOx reduction, overall impact of air pollution controls can be ambiguous when the assessments focus on the changes in pollutant concentrations. In this study, a risk-based method was used to gauge the net effect of air pollution controls on mortality risk in the Beijing–Tianjin–Hebei (BTH) region during the 2022 Winter Olympics and Paralympics (WOP). This mega-event presents a unique opportunity to investigate the efficacy of deep cuts in pollutant emissions. Results show that O3 concentrations greatly increased as nitrogen dioxide (NO2) concentrations decreased in the BTH. Due to the active photochemical formations, O3 became the dominant pollutant that affected human health during the WOP. Despite the substantial O3 increases, the health benefits of NO2 reductions overwhelmed the adverse health effects of O3 increases in most regions of the BTH (at 81 out of 112 stations). After considering the impacts of particulate matter, the integrated health risk of air pollution mixtures declined almost everywhere in the BTH. Our results underscore the great necessity of changing the assessment paradigm of pollution control from using concentration-based methods to using risk-based methods. Together with the carbon neutrality policy, stringent control of NOx emission from combustion sources is a promising way to achieve synergistic control solutions for air pollution and climate change.

Exposure of zebrafish to an environmental mixture of persistent organic pollutants triggers an increase in anxiety-like syndrome but does not affect boldness in unexposed offspring.

Polychlorinated biphenyls (PCBs) and polybrominated diphenyl ethers (PBDEs) are persistent organic pollutants (POPs) that are present as complex mixtures in all environmental compartments, including aquatic ecosystems. However, little is known about the effects of such complex mixtures on teleost behaviour. In this study, zebrafish (Danio rerio) were chronically exposed to an environmentally relevant mixture (MIX) containing 22 PCB and 7 PBDE congeners through diet from 5days post fertilization onwards. MIX-exposed F0 fish produced offspring (F1 and F2 generations) that were fed using plain food and grown until adulthood. In each generation, five behavioural traits (i.e. boldness, activity, sociality, exploration and anxiety) were evaluated by the mean of different experimental set-ups. Two distinct behavioural syndromes were identified: boldness, positively correlated to activity and exploration; and anxiety, associated with low sociality. F0 fish did not display any behavioural disruption resulting from POP exposure whereas F1 MIX fish were bolder than fish from other generations but did not differ significantly from F1 controls. F2 MIX fish displayed a higher anxiety syndrome than F2 controls. This is of particular importance since such behavioural changes in offspring generations may have persistent ecological consequences, may affect fitness and hence cause detrimental effects on wild fish populations exposed to POP mixtures.

Associations of personal PM2.5 and PM2.5-Bound polycyclic aromatic hydrocarbons exposure with blood lipid profiles: A panel study from middle-aged Chinese adults

Adverse effects of fine particulate matter (particulate matter ≤2.5 μm aerodynamic diameter, PM2.5) and PM2.5-bound polycyclic aromatic hydrocarbons (PAHs) on blood lipid profiles remain uncertain. We designed a panel study with repeated measures. In this panel study, we enrolled 215 adult residents who participated in two study periods from the Wuhan-Zhuhai cohort. Personal 24-h PM2.5, sixteen kinds of 24-h PM2.5-bound PAHs, and blood lipid profiles were repeatedly measured across two study periods. We observed that an interquartile-range increase in four-ring or five-ring PAHs was linked with a 0.112 and 0.108 mmol/l increase in triglyceride, respectively in single-constituent models. These associations remained robust in both constituent-PM2.5 joint models and single-constituent residual models. Additionally, we observed that the significant relationships of four/five-ring PAHs with triglycerides were stronger among females, non-smokers, and participants without hypertension and diabetes. Bayesian kernel machine regression models further revealed that combining sixteen kinds of PM2.5-bound PAHs as a mixture of pollutants could result in a cumulative toxic effect on total cholesterol and triglycerides. No significant relationships were observed between personal PM2.5 exposure and blood lipid changes. Our findings suggest that exposure to PM2.5-bound PAHs may adversely affect lipid metabolism, which provides new evidence for formulating pollution abatement strategies for cardiovascular health.

Comparative toxicological assessment of three soils polluted with different levels of hydrocarbons and heavy metals using in vitro and in vivo approaches

The biological effects induced by the pollutants present in soils, together with the chemical and physical characterizations, are good indicators to provide a general overview of their quality. However, the existence of studies where the toxicity associated to soils contaminated with mixtures of pollutants applying both in vitro and in vivo models are scarce. In this work, three soils (namely, Soil 001, Soil 002 and Soil 013) polluted with different concentrations of hydrocarbons and heavy metals were evaluated using different organisms representative of human (HepG2 human cell line) and environmental exposure (the yeast Saccharomyces cerevisiae, the Gram-negative bacterium Pseudomonas putida and, for the in vivo evaluation, the annelid Enchytraeus crypticus). In vitro assays showed that the soluble fraction of the Soil 001, which presented the highest levels of heavy metals, represented a great impact in the viability of the HepG2 cells and S. cerevisiae, while organic extracts from Soils 002 and 013 caused a slight decrease in the viability of HepG2 cells. In addition, in vivo experiments showed that Soils 001 and 013 affected the survival and the reproduction of E. crypticus. Altogether, these results provide a general overview of the potential hazards associated to three specific contaminated sites in a variety of organisms, showing how different concentrations of similar pollutants affect them, and highlights the relevance of testing both organic and soluble extracts when in vitro safety assays of soils are performed.

Treatment of Male Albino Rats with 5-fluorouracil and/or Cyclophosphamide Caused Serious Alterations in Sexual Hormones, Histological Structure of the Testis, and Semen Quality

Background: The therapeutic effect of Cyclophosphamide (CPA) is thus attributed to phosphoramide mustard and acrolein that leads to the formation of high level of reactive oxygen species (ROS), which results in decreased antioxidant activity. Excessive production of ROS could also culminate in oxidative stress. Objectives: The aim of this study is to evaluate the effect of sub lethal dose of the cyclophosphamide, 5-FU combination of 5-FU and CPA on testicular function, and histopathological alterations in male albino rats. These functions were monitored through some selected biochemical parameters and confirmed by DNA, RNA concentration and histopathological examination. Materials and Methods: Twenty-eight male adult rats were grouped randomly into four groups (n=7 each group), Five for biochemical studies and 2 for histological studies. Group I (control): Rats were injected with saline intraperitoneally and at a dose of 1.0 ml/kg b.w. for 14 days. Group II cyclophosphamide (CPA): Cyclophosphamide at a dose of 10 mg/kg day by day through i.p. to rats for 14 days. Group III Fluorouracil (5-FU): 5-Fluorouracil at a dose of 10 mg/kg day by day in saline was given through i.p. to rats for 14 days. Group IV (CPA+5-FU): Rats were given CPA followed by 5-FU at a dose of 10 mg/kg per day (day by day) through i.p. to rats for 14 days. At the end of the experimental period, rats were anesthetized using light ether. Blood and testes tissue samples were taken and prepared for biochemical and histological measurements. Biochemical parameters in rat serum and tissues were evaluated. Results: Treatment of male rats with CPA, 5-FU and their combination caused a significant decrease in sperm count, motility while increased dead and abnormal sperms compared to those of control. Co-treatment of CPA and 5-FU caused a significant decrease in sperm count, sperm motility and increase in abnormal sperms compared to individual treatment of CPA and 5-FU. Levels of testosterone, luteinizing hormone (LH) and follicle stimulating hormone (FSH) were decreased in the CPA, 5-FU and their combination-treated group. Co-treatment of 5-FU and CPA synergistically reduced testicular hormones compared with individual chemotherapy. Cyclophosphamide, 5-FU and their combination decreased testis DNA and RNA concentrations compared to the control. The combination of CPA and 5-FU was more effective to DNA and RNA compared to individual administration of the chemotherapy. Epididymis of the control rats showed normal histological structure with normal sperm density. Large tubules lined by pseudostratified columnar epithelium with abundant stereocilia projection from their surface. Long and dense processes of sperm tails were observed within the Lumina. The epididymis tubules of CPA-exposed rats were smaller and the majorities of them were free from mature spermatozoa. Epithelium contained numerous numbers of sloughed cells with cell debris in Lumina. 5-FU treated rat showed atrophy as well as necrosis, the arrangement of germ cells was disordered. The number of cell layers of the seminiferous tubules was significantly reduced. Epididymis of CPA+5-FU-treared rats showed necrotic degeneration and atrophy of the germinal cells, decrease spermatid when compared to CPA. Conclusion: It could be concluded that treatment of mammals with chemotherapy is associated with the production of free radicals that lead to hazardous alterations in sexual hormones, DNA, and RNA concentration, and histopathological structure in tistes and semin quality of male albino rats. However, 5-FU and CPA combination could produce a serious alteration in these parameters. Future work should consider combined chemotherapy regimens. Toxicological studies must be performed before using drugs as combination before application. Further research is required on toxicological impacts of drugs and pollutants mixtures.