Level Of Environmental Contamination Research Articles

Caesium-137 in the muscles of game animals in 2015-2022 – levels and time trend

Abstract Introduction Radioactive caesium-137 occurring in the environment may be taken up by plants and animals and pose a trophic threat to humans. Game animals living in forest ecosystems are very good bioindicators of the level of environmental contamination by ionising radiation. The main species measurably exposed to caesium-137 are the wild boar (Sus scrofa), the roe deer (Capreolus capreolus), and the red deer (Cervus elaphus). The study determined the levels of Cs-137 in muscle samples of these game animals in 2015–2022. Material and Methods Using gamma radiation spectrometry, 858 samples of game animal muscle tissue were examined: 508 wild boar, 145 roe deer and 205 red deer samples. Results Concentrations of Cs-137 varied widely (from minimum detectable activity (MDA) values to over 4,000 Bq/kg). In 63.4% of cases, the obtained concentrations exceeded the MDA. The permissible limit (600 Bq/kg for food) was exceeded in nine wild boar muscle samples, whereas it was not even exceeded once in roe or red deer muscle. The average concentration in wild boar was three times higher than in roe and red deer and amounted to 42.84 Bq/kg. The highest concentration of Cs-137 in wild boar muscle was 4,195 ± 372.0 Bq/kg, in roe deer muscle it was 111.5 ± 12.50 Bq/kg, and in red deer muscle was 86.70 ± 3.470 Bq/kg. Conclusion The seven years’ data indicate that wild boar absorb the most caesium-137 among game animals. The concentrations of Cs-137 in the muscle of game animals in the years 2015-2022 were at a nearly constant level, a very slow diminution being noticeable over time in roe and red deer muscle.

Prenatal exposure to environmental contaminants and cord serum metabolite profiles in future immune-mediated diseases.

Prenatal exposure to environmental contaminants is a significant health concern because it has the potential to interfere with host metabolism, leading to adverse health effects in early childhood and later in life. Growing evidence suggests that genetic and environmental factors, as well as their interactions, play a significant role in the development of autoimmune diseases. In this study, we hypothesized that prenatal exposure to environmental contaminants impacts cord serum metabolome and contributes to the development of autoimmune diseases. We selected cord serum samples from All Babies in Southeast Sweden (ABIS) general population cohort, from infants who later developed one or more autoimmune-mediated and inflammatory diseases: celiac disease (CD), Crohn's disease (IBD), hypothyroidism (HT), juvenile idiopathic arthritis (JIA), and type 1 diabetes (T1D) (all cases, N = 62), along with matched controls (N = 268). Using integrated exposomics and metabolomics mass spectrometry (MS) based platforms, we determined the levels of environmental contaminants and metabolites. Differences in exposure levels were found between the controls and those who later developed various diseases. High contaminant exposure levels were associated with changes in metabolome, including amino acids and free fatty acids. Specifically, we identified marked associations between metabolite profiles and exposure levels of deoxynivalenol (DON), bisphenol S (BPS), and specific per- and polyfluorinated substances (PFAS). Abnormal metabolism is a common feature preceding several autoimmune and inflammatory diseases. However, few studies compared common and specific metabolic patterns preceding these diseases. Here we hypothesized that exposure to environmental contaminants impacts cord serum metabolome, which may contribute to the development of autoimmune diseases. We found differences in exposure levels between the controls and those who later developed various diseases, and importantly, on the metabolic changes associated with the exposures. High contaminant exposure levels were associated with specific changes in metabolome. Our study suggests that prenatal exposure to specific environmental contaminants alters the cord serum metabolomes, which, in turn, might increase the risk of various immune-mediated diseases.

COVID-19 Pandemic Modulates the Environmental Contamination Level of Enteric Bacteria from WWTPs

The COVID-19 pandemic was a challenge for the whole world, and it had major secondary effects on humans and environmental health. The viral infection induced, in many situations, secondary bacterial infections, especially enteric infections, by destabilizing the balance of the gastrointestinal microbiota. The large-scale use of antibiotics and biocides for both curative and preventive purposes has resulted in an increase in bacterial resistance, and at the same time, the possibility of pathogenic microorganism multiplication and their dissemination to natural environments. Wastewater is the main vector of fecal microorganisms that favors their dissemination into natural aquatic ecosystems. The present paper aims to analyze the effect of the COVID-19 pandemic on the microbiological quality of wastewater from sewage treatment plants in Romania and its impact on receiving rivers. In order to highlight different and important areas in Romania, three cities from the east, center and west were selected for a microbiological evaluation of their WWTP influents and effluents from the pre-COVID-19 period and during the COVID-19 pandemic peak period, when the COVID-19 pandemic had a direct impact on WWTP microbial compositions. Our study shows that a higher level of contamination with fecal bacteria is linked to a higher COVID-19 incidence. The increased usage of pharmaceutical compounds, in turn, increases the number of resistant bacteria reaching the environment via WWTP effluents.

Productivity of bee families and biomonitoring of corbicular pollen and war-affected honeybee foraging sites with cultivated honey clover (Melilotus albus)

As a result of military actions, some territories of Ukraine have suffered technogenic loading on the environment. Of special concern is disturbed agricultural soils that are significant for food safety of the country. Soils affected by military actions require control of contamination and restoration of fertility. The studies revealed the advantages of cultivating honey clover (Melilotus albus) in war-affected soils and controlling content of heavy metals in soils and corbicular pollen from honey clover cultivated in those soils. In gray forest average-loamy soils that had been affected by military actions, nitrogen content increased 6.3% thanks to cultivation of M. albus. High nitrogen content in soil improves its fertility. Cultivation of M. albus in affected soils promoted more intensive growth of the bee families, encouraging them to gather nectar more actively. As a result, this apiary produced greater amounts of honey, corbicular pollen, and bee pollen. The conducted studies revealed heightened levels of lead, cadmium, and zinc in the war-impacted agricultural land, compared with the territory beyond the impact zone. This caused increased content of heavy metals in corbicular pollen from M. albus. Contamination of corbicular pollen from M. albus manifested in excess over the allowable norms of cadmium, lead, and zinc. At the same time, the highest coefficient of transfer from soil into corbicular pollen was found for zinc. The high degree of contamination of the soil with heavy metals as a result of military action promoted a high level of ingress of lead and cadmium into the corbicular pollen, compared with the situation in clean territory. The study results expand the available data on biomonitoring of apiary products and foraging lands in contaminated areas. Analysis of the corbicular pollen and pollen can give information about the level of environmental contamination and help evaluate the ecological state of melliferous sites. Such a monitoring can be useful for decision making regarding the protection of the environment and healthcare.

Abundance and risk assessment of microplastics in water, sediment, and aquatic insects of the Nile River

Microplastics (MPs) are a serious threat in freshwater environments. The ecological risk and abundance level of MPs in abiotic and biotic compartments of the Nile River haven't been systematically reported. Thus, these issues were highlighted in the present study during different seasons of the sampling year. The results showed that MP concentrations in the river ranged from 2.24 ± 0.6 to 3.76 ± 1.1 particles/L, 298 ± 63 to 520 ± 80 particles/kg dry weight, and 0.081 ± 0.051 to 4.95 ± 2.6 particles/individual in surface water, sediment, and different species of aquatic insects, respectively. All the extracted MPs are colored blue, red, and black. Fiber-shaped polyesters (<500–1500 μm) were the most common MPs in all the river compartments. MPs' dominance was observed during the summer in comparison with that in the other seasons. Environmental risk indicators indicate the high ecological risk of MPs, which are widely distributed in the Nile River. In conclusion, MP consumption by aquatic insects may not only be related to levels of environmental contamination, since other variables, such as taxon size, weight, and particular feeding behavior, may also be significant. Additionally, the presence of MPs in insects (at lower trophic levels) creates the potential for predation-based inter-trophic level transmission. Thus, higher trophic-level investigations of various feeding groups should be carried out to identify any possible harm that MPs cause to various aquatic organisms.

Impact of Bacillus licheniformis from yaks following antibiotic therapy in mouse model.

Gut microorganism (GM) is an integral component of the host microbiome and health system. Abuse of antibiotics disrupts the equilibrium of the microbiome, affecting environmental pathogens and host-associated bacteria alike. However, relatively little research on Bacillus licheniformis alleviates the adverse effects of antibiotics. To test the effect of B. licheniformis as a probiotic supplement against the effects of antibiotics, cefalexin was applied, and the recovery from cefalexin-induced jejunal community disorder and intestinal barrier damage was investigated by pathology, real-time PCR (RT-PCR), and high-throughput sequencing (HTS). The result showed that A group (antibiotic treatment) significantly reduced body weight and decreased the length of jejunal intestinal villi and the villi to crypt (V/C) value, which also caused structural damage to the jejunal mucosa. Meanwhile, antibiotic treatment suppressed the mRNA expression of tight junction proteins ZO-1, claudin, occludin, and Ki67 and elevated MUC2 expression more than the other Groups (P < 0.05 and P < 0.01). However, T group (B. licheniformis supplements after antibiotic treatment) restored the expression of the above genes, and there was no statistically significant difference compared to the control group (P > 0.05). Moreover, the antibiotic treatment increased the relative abundance of 4 bacterial phyla affiliated with 16 bacterial genera in the jejunum community, including the dominant Firmicutes, Proteobacteria, and Cyanobacteria in the jejunum. B. licheniformis supplements after antibiotic treatment reduced the relative abundance of Bacteroidetes and Proteobacteria and increased the relative abundance of Firmicutes, Epsilonbacteraeota, Lactobacillus, and Candidatus Stoquefichus. This study uses mimic real-world exposure scenarios by considering the concentration and duration of exposure relevant to environmental antibiotic contamination levels. We described the post-antibiotic treatment with B. licheniformis could restore intestinal microbiome disorders and repair the intestinal barrier. KEY POINTS: • B. licheniformis post-antibiotics restore gut balance, repair barrier, and aid health • Antibiotics harm the gut barrier, alter structure, and raise disease risk • Long-term antibiotics affect the gut and increase disease susceptibility.

Nanocrystalline iron hydroxide lignocellulose filters for arsenate remediation.

Harmful levels of environmental contaminants, such as arsenic (As), persist readily in the environment, threatening safe drinking water supplies in many parts of the world. In this paper, we present a straightforward and cost-effective filtration technology for the removal of arsenate from potable water. Biocomposite filters comprised of nanocrystalline iron oxides or oxyhydroxides mineralized within lignocellulose scaffolds constitute a promising low cost, low-tech avenue for the removal of these contaminants. Two types of iron oxide mineral phases, 2-line ferrihydrite (Fh) and magnetite (Mt), were synthesized within highly porous balsa wood using an environmentally benign modification process and studied in view of their effective removal of As from contaminated water. The mineral deposition pattern, minerology, as well as crystallinity, were assessed using scanning electron microscopy, transmission electron microscopy, micro-computed X-ray tomography, confocal Raman microscopy, infrared spectroscopy, and X-ray powder diffraction. Our results indicate a preferential distribution of the Fh mineral phase within the micro-porous cell wall and radial parenchyma cells of rays, while Mt is formed primarily at the cell wall/lumen interface of vessels and fibers. Water samples of known As concentrations were subjected to composite filters in batch incubation and gravity-driven flow-through adsorption tests. Eluents were analyzed using microwave plasma optical emission spectroscopy (MP-AES) and inductively coupled plasma mass spectrometry (ICP-MS). By subjecting the filters to a flow of contaminated water, the time for As uptake was reduced to minutes rather than hours, while immobilizing the same amount of As. The retention of As within the composite filter was further confirmed through energy-dispersive X-ray mappings. Apart from addressing dangerously high levels of arsenate in potable water, these versatile iron oxide lignocellulosic filters harbor tremendous potential for addressing current and emerging environmental contaminants that are known to adsorb on iron oxide mineral phases, such as phosphate, polycyclic aromatic hydrocarbons or heavy metals.

Microplastic burden in marine benthic invertebrates depends on species traits and feeding ecology within biogeographical provinces

The microplastic body burden of marine animals is often assumed to reflect levels of environmental contamination, yet variations in feeding ecology and regional trait expression could also affect a species’ risk of contaminant uptake. Here, we explore the global inventory of individual microplastic body burden for invertebrate species inhabiting marine sediments across 16 biogeographic provinces. We show that individual microplastic body burden in benthic invertebrates cannot be fully explained by absolute levels of microplastic contamination in the environment, because interspecific differences in behaviour and feeding ecology strongly determine microplastic uptake. Our analyses also indicate a degree of species-specific particle selectivity; likely associated with feeding biology. Highest microplastic burden occurs in the Yellow and Mediterranean Seas and, contrary to expectation, amongst omnivores, predators, and deposit feeders rather than suspension feeding species. Our findings highlight the inadequacy of microplastic uptake risk assessments based on inventories of environmental contamination alone, and the need to understand how species behaviour and trait expression covary with microplastic contamination.

Environmental distribution of Echinococcus- and Taenia spp.-contaminated dog feces in Kyrgyzstan.

Recently, there have been epidemics of human cystic echinococcosis (CE) and alveolar echinococcosis (AE) in Kyrgyzstan. This study investigated 2 districts for the presence of Echinococcus granulosus s.l. and Echinococcus multilocularis eggs; species identity was confirmed by polymerase chain reaction in dog feces and the level of environmental contamination with parasite eggs in 2017–2018 was also investigated. In the Alay district 5 villages with a high reported annual incidence of AE of 162 cases per 100 000 and 5 villages in the Kochkor district which had a much lower incidence of 21 cases per 100 000 were investigated. However, the proportion of dog feces containing E. granulosus s.l. eggs was ~4.2 and ~3.5% in Alay and Kochkor respectively. For E. multilocularis, the corresponding proportions were 2.8 and 3.2%. Environmental contamination of Echinococcus spp. eggs was estimated using the McMaster technique for fecal egg counts, weight and density of canine feces. The level of environmental contamination with E. multilocularis eggs was similar at 4.4 and 5.0 eggs per m2 in Alay and Kochkor respectively. The corresponding values for E. granulosus s.l. were 8.3 and 7.5 eggs per m2. There was no association between village or district level incidence of human AE or CE and the proportion of dog feces containing eggs of Echinococcus spp. or the level of environmental contamination. Increased contamination of taeniid eggs occured in the autumn, after the return of farmers with dogs from summer mountain pastures.

Potentially toxic element bioaccumulation in consumed indoor shrimp farming associated with diet, water and sediment levels

Shrimp production is an important industry for many countries and shrimp consumption is increasing worldwide. Shrimps are a highly nutritional food, but can pose a risk for human health if subject to high levels of environmental contaminants. This work studies the presence of As, Cd, Co, Cr, Cu, Hg, Ni, Pb and Zn in shrimps from Ecuador and compares them to such contents noted in other shrimp-production areas in the world to evaluate the possible risks associated with these elements for consumer health, and to relate them to potentially toxic element (PTE) contents in water, sediments and diets, and also to animal biometric parameters. The PTE levels (mg kg−1 DM) obtained are as follows: in the head—As (3.52–6.11), Cd (0.02–0.10), Co (0.14–0.49) Cr (0.23–4.89), Cu (99.9––233.0), Ni (0.52–1.86), Pb (0.24–1.09), Zn (51.8–100.5) and Hg (μg kg−1 DM) (10.00–66.81); in the tail—(0.91–3.21), Cd (0.01–0.02), Co (0.01–0.43) Cr (0.01–6.52), Cu (20.0–72.44), Ni (0.15–2.03), Pb (0.01–0.69), Zn (31.2–66.1) and Hg (μg kg−1 DM) (10.00–67.18). The concentration of all the PTEs is generally lower than the limits set for seafood by European regulations, except for As in the cephalothorax (4.63 mg kg−1). Different behaviours for PTE accumulation in shrimps were found, which preferentially tend to accumulate in the cephalothorax, except for Hg (40.13 μg kg−1 DM), which accumulates in muscle (body) and is associated with contents of proteins, lipids and total shrimp weight. Nonetheless, the target hazard quotient (THQ) values for PTEs indicate that the consumption of shrimp muscles from Ecuador does not pose a human health risk because the values of these indices are below 1 in all cases.

Levels of environmental contamination with SARS-CoV-2 in hospital rooms and salivary viral loads of patients with coronavirus disease 2019

BackgroundClarifying the presence of viable severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) rather than SARS-CoV-2 viral RNA in inpatient rooms is important for infection control of coronavirus disease 2019 (COVID-19). In this study, we investigated levels of viral RNA and viable virus on environmental surfaces and in patient saliva. MethodsEnvironmental samples from 23 sites in hospital rooms were collected every other day until patient discharge. Saliva specimens and samples from the inner surface of patient masks were also collected. Additionally, environmental samples were collected from 46 sites in hospital rooms on discharge day. The samples were examined using quantitative reverse transcription polymerase chain reaction (RT-qPCR) and plaque assays. ResultsThe 10 enrolled cases were classified as mild COVID-19, and patients were discharged after 6–9 days. The viral RNA was detected in 12.4% (105/849) of serially collected environmental samples during hospitalization, whereas viable virus was detected only in 0.47% (4/849), which were from sinks and tap levers. Although all patients recovered, three cases retained viable virus in the last saliva specimen collected. In the 15 discharged rooms, viral RNA was detected in 6.6% (45/682) of the samples, and viable virus was detected in only one sample from the sink. ConclusionsAlthough environmental surfaces surrounding patients with COVID-19 were frequently contaminated with viral RNA, the presence of viable virus was rare and limited only to areas around sinks. These results suggest that contact infection risk via fomites in hospital rooms is extremely rare.

Glacier foreland insect uptake synthetic compounds: an emerging environmental concern.

Pesticides, synthetic fragrances and polycyclic aromatic hydrocarbons contaminated two glacier-fed streams (Amola, Mandrone) and one spring (Grostè) in the Italian Alps. Ten compounds (chlorpyrifos (CPY), chlorpyrifos-methyl (CPY-m), galaxolide (HHCB), tonalide (AHTN), fluorene (Flu), phenanthrene (Phen), anthracene (Ant), fluoranthene (Fl), pyrene (Pyr), benzo[a]anthracene (BaA)) accumulated in aquatic larvae of chironomids (Diamesa steinboecki, D. latitarsis, D. bertrami, D. tonsa, D. zernyi, Pseudokiefferiella parva, Orthocladiinae) and tipulids. Their tissue concentrations (detected by gas chromatography coupled with mass spectrometry) ranged from 1.1 ± 0.1ng/g d.w. (= dry weight) (CPY-m in D. tonsa from Amola) to 68.0 ± 9.1ng/g d.w. (Pyr in D. steinboecki from Mandrone). HHCB, AHTN, and CPY, with one exception, were accumulated by all aquatic insects. Six compounds (CPY, CPY-m, HHCB, AHTN, Fl, Pyr) also contaminated carabids (Nebria germarii, N. castanea, N. jockischii) predating adults of merolimnic insects. Their tissue concentrations ranged from 1.1 ± 0.3ng/g d.w. (CPY-m in N. germarii from Mandrone) to 84.6 ± 0.3ng/g d.w. (HHCB in N. castanea from Grostè). HHCB and AHTN were accumulated by all Nebria species. Intersite and interspecies differences were observed, which might be attributed to different environmental contamination levels. There was a stronger similarity between species from the same site than among the same species from different sites, suggesting that uptake is not species specific. At all sites, the concentration of xenobiotics was higher in larvae than in water and comparable or higher in carabids than in larvae from the same site, suggesting trophic transfer by emerging aquatic insects to their riparian predators.

Estimating the impact of low temperature on African swine fever virus transmission through contaminated environments.

African Swine Fever Virus (ASFV) is the cause of an infectious disease in pigs, which is difficult to control. Long viability of ASFV has been shown for several contaminated materials, especially under low temperature. Therefore, when pigs are exposed to a contaminated environment, new infections could occur without the presence of infectious individuals. For example, a contaminated, poorly washed, empty livestock vehicle poses a risk to the next load of pigs. A quantitative stochastic environmental transmission model was applied to simulate the change in environmental contamination levels over time and calculate the epidemic parameters through exposure-based estimation. Due to the lack of experimental data on environmental transmission at low temperatures, we performed a non-linear fit of the decay rate parameter with temperature based on a literature review. Eventually, 16 scenarios were constructed for different temperature (at 20°C, 10°C, 0°C, or -10°C) and duration of empty periods (1, 3, 5, or 7 days) after the environment had been contaminated. We quantified the variation in the contamination level of the environment over time and the probability of newly added recipients getting infected when exposed to the environment after the empty period. As a result, the transmission rate parameter for ASFV in pigs was estimated to be 1.53 (0.90, 2.45) day-1, the decay rate parameter to be 1.02 (0.73, 1.47) day-1 (at 21°C), and the excretion rate parameter to be 2.70 (2.51, 3.02) day-1. Without washing and disinfecting, the environment required 9, 14, 24, 54 days to reach a low probability of causing at least one new case (<0.005) at 20°C, 10°C, 0°C, -10°C, respectively. In addition, the method proposed in this paper enables assessment of the effect of washing and disinfecting on ASFV environmental transmission. We conducted this study to better understand how the viability of ASFV at different temperatures could affect the infectivity in environmental transmission and to improve risk assessment and disease control strategies.

Photoelectrocatalytic Degradation of Cyanide Using TiO2 on Conducting Glass and Polarographic Analysis of the Products

Cyanide used in gold mines is collected in tailing dams and has a high risk of contaminating the surrounding environment. Cyanide contaminations in the atmosphere, as well as in water and soil are insufficiently studied so far. The lack of interest, the complexity of the reaction mechanisms and the challenging analysis of the products are major reasons for this deficiency. The circumstance that a prominent part of cyanide is volatilsed during and after the gold extraction is often neglected; volatalised HCN is said to be sufficiently destroyed by the sunlight and the oxygen of the atmosphere which can easily be disproved by analysis of the cyanide content in the contaminated atmosphere. The investigation of the products of cyanide decomposition is an essential part in the evaluation of the toxicity originating from effluents of gold processing. In this work, spray pyrolysed TiO2 on conducting glass is used for the photoelectrocatalytic treatment of cyanide. In UV-A irradiating the catalyst and applying an external bias for the separation of the charge carriers, the cyanide is oxidised in solutions of different pH. The cyanide content after the process as well as the quantity of the products is analysed via polarography. Besides the oxidation, hydrolysis was detected as well, correlating to the pH of the solutions. The proposed method allows the evaluation of the level of environmental contamination of gold processing as well as the analysis of products that result from decontamination processes in gold mines. Furthermore the photocatalytic capability of TiO2 for the decontamination of cyanide wastewaters is determined.

Description of the multi-dimensional environment at the territorial scale: A holistic framework using cluster analysis and open data in France

The impact of the environment on health is usually studied in a segmented manner, with a focus on a single source, pollutant, or exposure medium. To better understand spatial health inequalities, it is necessary to adopt multi-dimensional approaches to comprehensively describe the environment, especially at the territorial level. Clustering methods, which allow for the development of territorial typologies, are particularly interesting for this purpose. By simplifying complex datasets, these methods may reveal spatial patterns and geographical phenomena that would otherwise be difficult to observe. Based on the existing literature, there is a clear need for large-scale territorial typologies that comprehensively address the physical and outdoor environment.A robust and transposable framework was developed and applied to 3,041 municipalities in Northern France using open environmental data. It consists of five main steps: data collection, data selection, data preparation, cluster analysis, and cluster interpretation. This methodology allows for the development of an environmental classification of municipalities by identifying the primary environmental profiles represented in the study area. Cluster detection was performed based on 39 spatialized indicators that describe the level of environmental contamination (air, water, soil), the level of pollutant emissions, the proximity to emission sources, the land use, the agricultural practices, and the degree of naturalness in every municipality. As a result, municipalities were allocated into one of the seven following environmental profiles: (i) Dense urban centers; (ii) Peripheral urban municipalities; (iii) Intensive agricultural municipalities under urban influence; (iv) Intensive agricultural municipalities beyond urban influence; (v) More extensive and diversified agricultural municipalities; (vi) Municipalities with predominant livestock activities and significant natural areas; (vii) Municipalities with predominant natural areas: forests, wetlands, and water surfaces. The resulting typology goes far beyond a simple description of the urban–rural continuum. Five profiles of rural municipalities were identified, primarily distinguished by agricultural practices, degree of naturalness, and intensity of urban pressure.This approach enables researchers to identify the combination of environmental factors that shape a territory. It provides a more comprehensive and nuanced understanding of how environmental pressures and amenities are distributed in space and overlap with each other. By linking these typologies with health data, it could provide new insights into the etiology of complex diseases with unidentified environmental risk factors. Relying on open data, this framework is a valuable tool to assess etiological hypotheses at the territorial level.

Prenatal exposure to persistent organic pollutants and molar-incisor hypomineralization among 12-year-old children in the French mother-child cohort PELAGIE

BackgroundExceptional episodes of exposure to high levels of persistent organic pollutants have already been associated with developmental defects of enamel among children, but knowledge is still scarce concerning the contribution of background levels of environmental contamination. MethodsChildren of the French PELAGIE mother-child cohort were followed from birth, with collection of medical data and cord blood samples that were used to measure polychlorinated biphenyls (PCBs), organochlorine pesticides (OCs), and perfluorinated alkyl substances (PFASs). At 12 years of age, molar-incisor hypomineralization (MIH) and other enamel defects (EDs) were recorded for 498 children. Associations were studied using logistic regression models adjusted for potential prenatal confounders. ResultsAn increasing log-concentration of β-HCH was associated with a reduced risk of MIH and EDs (OR = 0.55; 95% CI, 0.32–0.95, and OR = 0.65; 95% CI, 0.43–0.98, respectively). Among girls, intermediate levels of p,p’-DDE were associated with a reduced risk of MIH. Among boys, we observed an increased risk of EDs in association with intermediate levels of PCB 138, PCB 153, PCB 187, and an increased risk of MIH with intermediate levels of PFOA and PFOS. ConclusionsTwo OCs were associated with a reduced risk of dental defects, whereas the associations between PCBs and PFASs and EDs or MIH were generally close to null or sex-specific, with an increased risk of dental defects in boys. These results suggest that POPs could impact amelogenesis. Replication of this study is required and the possible underlying mechanisms need to be explored.

Environmental contamination levels based on geochemical properties of soils from direct influence areas of hydroelectric power plants

Environmental contamination levels based on geochemical properties of soils from direct influence areas of hydroelectric power plants

Toxic Metal Concentrations and Exposure Risks Associated with Surface Water, Seafood (Clarias gariepinus, Oreochromis niloticus, Cottus gobio) and Vegetable (Telfairia occidentalis) from Elebele River, Nigeria

Human exposure to elevated levels of environmental contaminants is an important concern of health toxicology. This study assessed the toxicity level of toxic metals including Arsenic (As), Cadmium (Cd), Chromium (Cr), Copper (Cu), Lead (Pb) and Nickel (Ni) in samples of water, seafood (Clarias gariepinus, Oreochromis niloticus, Cottus gobio) and vegetable (Telfairia occidentalis) from the adjacent area of Elebele River, Nigeria, bioconcentration and toxic metal exposure posed to communities consuming these foodstuffs. The following indices: single-factor index and the comprehensive pollution index, metal pollution index, estimated daily and weekly intakes, hazard index and lifetime cancer risk were applied. Samples of water, seafood and vegetable were analysed using Atomic Absorption Spectrophotometer. The results showed that the concentrations of metals except for Cd in water samples were higher than the permissible limits by international organisations. Results also revealed that the concentrations of metals in foodstuff samples were within limits. Furthermore, the values of estimated weekly intakes calculated were lower than the limits of provisional tolerable weekly intakes established by the Food and Agriculture Organization and World Health Organization. This suggests no health risks and is consistent with the HI results. However, As was a major contributor (96.9%) to health risks associated with the ingestion of water. Lifelong consumption of T. occidentalis might be hazardous in the study locality. The carcinogenic risk was &gt; 1 × 10‒4 for As and Ni. Therefore, to reduce the health risk and the extent of metal contamination, steps must be taken for the efficient removal of metals from the water body.

Histopathological and health risk assessment of heavy metals in the straw-colored fruit bat, Eidolon helvum, in Nigeria.

There is heightening concern regarding heavy metals environmental pollution requiring renewed global attention because of their bioaccumulation and toxicity at varying levels. The concern is most important in the highly migratory Eidolon helvum (E. helvum) that is very common and traverses wide geographical areas within the sub-Saharan Africa. The present study aimed to evaluate levels of cadmium (Cd), lead (Pb), and zinc (Zn) bioaccumulation in 24 E. helvum of both sexes from Nigeria to assess their indirect health risks to the human consumers of the bats in addition to their direct bioaccumulation and toxic damages in the bats themselves based on standard procedures. Lead, Zn, and Cd bioaccumulation concentrations were 2.83 ± 0.35, 0.42 ± 0.03, and 0.05 ± 0.01mg/kg, respectively, with significant (p < 0.05) Pb bioaccumulation compared to either Cd or Zn in the affected bats. However, only Pb (markedly) and Cd (marginally) bioaccumulated above small mammals' critical threshold levels as there are no existing established threshold levels for bats. Sex played no major role in their bioaccumulation levels. The bioaccumulation levels posed no life-long non-carcinogenic nor carcinogenic risks to the human consumers of the bats at detected concentrations. The observed lungs, liver, and kidney histopathological changes suggested the possible direct effects of the metals in the bats. Nevertheless, other anthropogenic factors might be responsible as no significant (p > 0.05) correlation existed between cellular changes and the bioaccumulation levels. The presence of the heavy metals and their bioaccumulations above critical threshold levels suggested some levels of environmental contamination and pollution, which might have direct and indirect health implications to the bats and their human consumers.

Residues of an anthelmintic veterinary drug (closantel) detected in red foxes (Vulpes vulpes) in Scotland

The contamination of the environment by some veterinary medicines and their impact on wild animals is of increasing concern. However, there is a lack of information about their residues in wildlife. The sentinel animals most commonly used for monitoring the level of environmental contamination are birds of prey, and information on other carnivores and scavengers scarce. This study examined the livers from 118 foxes for residues of a range of 18 veterinary medicines (16 anthelmintic agents and 2 metabolites) used on farm livestock. The samples were collected from foxes, primarily in Scotland, shot during legal pest control activities conducted between 2014 and 2019. Closantel residues were detected in 18 samples, and the concentrations found ranged from 6.5 µgkg−1 to 1383 µgkg−1. No other compounds were found in significant quantities. The results show a surprising frequency and level of closantel contamination, raising concerns about both the route of contamination and the potential impacts on wild animals and the environment, such as the potential for significant wildlife contamination to contribute to the development of closantel-resistant parasites. The results also suggest that red fox (Vulpes vulpes) could be a useful sentinel species for detecting and monitoring some veterinary medicine residues in the environment.