Highest Average Concentration Research Articles

Anthropogenic and biogenic pollutants in a forested environment: SPRUCE-22 campaign overview

The SPRUCE-22 field campaign was conducted during July 2022 on a remote mountainous forested site in Greece to assess interactions of biogenic and anthropogenic pollutants in the Eastern Mediterranean. Particle chemical composition and size distributions along with concentrations of organic and inorganic gases were measured at high temporal resolution, while samples were collected and analyzed off-line. PM1 had a surprisingly high average concentration of 13 μg m−3 consisting primarily of organics (57%), followed by sulfate (30%), ammonium (9%), and black carbon (2%). Nitrates (both inorganic and organic) were less than 1% of the PM1 despite the relatively high NOx emissions in the Balkans. The PM2.5 concentrations at this remote site were similar and even higher than those in major cities across Greece including Athens, indicating the importance of regional transport for summertime pollution in the Eastern Mediterranean. The relatively constant average diurnal profiles of major anthropogenic pollutants are consistent with only minimal effects from local sources. Sulfates are not any more the dominant component of fine PM in Greece due to the reduction of SO2 emissions of coal-burning powerplants. The organic aerosol (OA) was quite oxidized with an average oxygen to carbon ratio (O:C) equal to 0.83. The average concentration of isoprene was 0.6 ppb, of monoterpenes 0.5 ppb, while the biogenic secondary organic aerosol factor (obtained through source apportionment analysis) was estimated to contribute 22% of the OA. Additional biogenic secondary organic aerosol (SOA) may be part of the two oxygenated OA (OOA) factors that were also identified. Radiocarbon analysis indicated that the non-fossil carbon was approximately equal to the sum of the biogenic and the more oxidized oxygenated OA, implying that the less oxidized OOA in this study was mostly associated to anthropogenic fossil fuel combustion. The biogenic SOA was quite aged (O:C equal to 0.63) and was also mostly transported to the site. Nearby new particle formation events occurred during 20 % of the days, with an average SO2 concentration of 0.3 ppb. The oxidative potential of the PM per unit of mass was quite high. The source attribution of the fine PM and the interactions among its anthropogenic and biogenic components are also discussed.

Effects of massive desiccation of olive waste residues on air quality

New industries are proliferating in the recovery of agri-food wastes, such as those involved in the revaluation of alperujo, generated in the production of olive oil. Despite the potential environmental benefits, their activity is not exempt from new forms of emissions, aggravated by the massification of waste treatments.This work reports a six-month field campaign carried out in an alperujo desiccation plant which can serve as a proxy for these emerging industries in the Mediterranean countries. The study focused on air quality parameters, covering criteria pollutants, metals and microbiological load of particulate matter and the characterization of volatile organic compounds (VOCs).The results show a slight contribution of the factory to the NOx levels in the surroundings (3.0–12.5 μg/m3). Statistically significant effects were not observed for ozone, CO, SO2, or PM10. Concerning the levels of metals, concentrations were low and calculated health risk indexes indicated safe conditions in the area. The most abundant elements were Na (6.5 × 102 ng/m3), K (4.0 × 102 ng/m3), Al (2.7 × 102 ng/m3), Zn (2.1 × 102 ng/m3), Ca (2.16 × 102 ng/m3), Fe (3.6 × 101 ng/m3) and Mg (3.2 × 101 ng/m3).Bacterial counts, with a mean value of 15.9 CFU/m3, showed a seasonal shift, mainly explained by weather (air moisture and temperature) and PM2.5 concentration. The genomic analysis showed Cutibacterium as the dominant genus during the cold months while Bacillus predominated in the warm season.The VOCs with higher average concentrations were acetic acid (130 μg/m3), nonanoic acid (124 μg/m3), benzoic acid (29.7 μg/m3), octanoic acid (19.9 μg/m3) and nonanal (4.70 μg/m3), with the rest of compounds in concentrations below 4 μg/m3. Odorant pollutants with the greatest contribution to olfactory nuisance were aldehydes (from pentanaldehyde to decanaldehyde), acetic acid and phenol.Although the observable effects of the waste treatments were low, several parameters showed an influence on the environment which should be assessed to foresee and prevent long-term consequences.

Tissue distribution and residue depletion of difloxacin in crucian carp (Carassius carassius) after multiple oral administration

Although difloxacin is not listed by Codex or the US FDA, China and some countries in Asia have approved this drug for use in aquaculture. Additionally, both China and EMA have adopted the same maximum residue limit (MRL) for difloxacin in muscle plus skin at 0.3 μg/g. However, a withdrawal period has not been established for difloxacin in aquaculture. Therefore, the primary goal of this investigation was to evaluate the tissue distribution and residue depletion of difloxacin in crucian carp (Carassius carassius) kept in freshwater at a temperature of 21 ± 1 °C, with the aim of determining an appropriate withdrawal period. This investigation entailed the oral administration of difloxacin via gavage, employing a daily dosage of 20 mg/kg body weight (BW) over a consecutive three-day regimen. Diverse samples, including plasma, bile, skin-on-muscle, liver, kidney, intestine, and gill, were collected at predetermined time intervals after the final administration. The quantification of difloxacin concentrations in all collected samples was carried out utilizing a high-performance liquid chromatography (HPLC) method. Difloxacin exhibited extensive distribution within crucian carp, with detectable presence in all examined tissues. The highest average concentration was notably observed in the bile with a Cmax of 14.359 μg/mL. Remarkably, even on the 15th day (360 h) following the final dosing, traces of difloxacin residues remained detectable in all collected samples. Pharmacokinetic parameters, determined through the noncompartmental model, unveiled diverse elimination half-lives (t1/2λzs) for difloxacin across distinct samples, ranging from rapid to slow: plasma (9.46 days), skin-on muscle (10.15 days), liver (10.36 days), bile (13.05 days), intestine (20.94 days), kidney (22.12 days), and gill (29.56 days). Taking into consideration the MRL, a withdrawal period of 32 days was definitively determined, derived from the upper limit of the one-sided 95% confidence interval. When converted to the unit of °C-day, the withdrawal period was determined to be 660.

Petrographic and geochemical study of Precambrian and Paleozoic rocks in the western Anti-Atlas belt, Morocco: Facies, weathering, provenance and economic exploitation

Detrital and volcanic-detrital rocks from the Ifni Buttonhole and Lakhssas Plateau were analyzed to determine their provenance, compositional maturity, and alteration source. Geochemically, the sediments were classified as arkoses, lithic arenites, grauwackes, sandstones, lithic arenites, and Fe-rich sands, indicating low compositional and mineralogical maturity. A high average SiO2 concentration and low Al2O3 were consistent with a low abundance of shale and clay components. The geochemical signatures of the detrital and volcano-detrital (RDVD) rocks indicate that they have undergone a moderate to low degree of chemical alteration. The CIA study also suggests that the granitic, granodioritic rocks represent the source provenance which, during weathering and transport, supplied the detritus to the supra-crustal units. The major trace element data suggest that these rocks are largely derived from felsic igneous rocks, namely granitoids, with a minor contribution from intermediate sources. The carbonate rocks do not represent a wide variety of facies: dolomitic limestone, calcareous limestone, and calcaro-dolomitic chert. Calcitic and dolomitic samples show a linear increase in SiO2, regardless of their CaO/LOI ratio values, which remain relatively constant. The highest SiO2 contents are observed in the calc-dolomitic chert. Geochemical analysis of RDVD from the Ifni buttonhole determined their origin, maturity, and alteration. Major oxides decreased with higher silica content, indicating quartz control. Samples, formed under semi-arid conditions, show maturity under stable deposition. They suggest a felsic, recycled source, with moderate alteration and zircon enrichment during recycling. In the study area, limestones and dolomites serve as materials applicable in the building sector, suitable for all types of concrete. The Taliwine Formation harbors Lower Cambrian dolomites and limestones, ideal for mosaic aggregates. Described as variable in color, compact, homogeneous, very hard, and resistant to alteration, the plutonic rocks form prominent peaks. They exhibit both subalkaline characteristics in granitoids and an alkaline trend in dolerite dykes. Most samples display minimal alteration, indicating the reliability of their major element compositions for geochemical analyses. These granitoids constitute valuable deposits for ornamental and building rock purposes.

Investigation the Level of Groundwater Pollution with Heavy Metals in Mazar-e-Sharif City

The majority of drinking and consumable water sources for the residents of Mazar-e-Sharif city are supplied from underground water. Climate variations, depletion of underground water, pollution resulting from human activities, agriculture, industrial processes, and urban development have significantly impacted the quality of underground water in this region. In this research, the quality of groundwater in terms of contamination with heavy metals such as manganese, copper, aluminum, iron, cadmium, mercury, lead, and arsenic was investigated. Twenty-four random well samples were collected based on international sampling standards, and temperature and pH parameters were measured on-site. The concentration of heavy metals was measured using an atomic absorption spectrophotometer. Data analysis was performed using Excel and SPSS software, and GIS software was utilized for mapping the sampled points. Laboratory results indicated that the lead concentration in wells W6, W11, W20, and W22 was 0.014, 0.013, 0.02, and 0.012 milligrams per liter, respectively. The aluminum concentration in wells W5, W16, and W17 was 0.6, 0.5, and 0.4 milligrams per liter, respectively, and the cadmium concentration in well W3 was 0.005 milligrams per liter. The concentrations in these wells exceeded the recommended limits set by the World Health Organization (WHO). In the remaining wells, the concentrations of heavy metals were below the WHO limits. Descriptive statistics results showed that copper had the highest average concentration, and arsenic had the lowest concentration. Since underground water is the sole source of drinking and consumable water for the city's residents, it is recommended to conduct a systematic study of heavy metal concentrations in groundwater sources to reduce the adverse effects of contaminated water in certain wells.

Minerals levels in sugarcane syrup

Sugarcane syrup derived from evaporating sugarcane juice serves as both a self-consumed product and a dietary supplement. It retains nutrients in sugarcane juice, especially minerals and nutritional compounds resistant to cooking processes. This study evaluated the mineral content of Brazilian sugarcane syrup by using Inductively Coupled Plasma Optical Emission Spectrometry. The syrup was found to have high concentrations of potassium, magnesium, calcium, and phosphorus (340, 57, 49, and 48 mg 100 g-1, respectively). Although the qualitative mineral composition of the evaluated products was relevant and consistent, there was considerable quantitative variation; therefore, standardization based on a narrow range of acceptable values is not recommended. It would take 243-1157 g of syrup to replace 200 g of whole cow’s milk. Nonetheless, sugarcane syrup contains essential minerals with proven health benefits. Potassium had the highest average concentration (up to 781.53 mg 100 g-1), followed by magnesium (10.82-94.69 mg 100 g-1), with iron ranking fifth (8.82 mg 100 g-1). Despite the quantitative variation, the qualitative mineral composition remained relevant. Therefore, a narrow standardization based on a limited range of values is not recommended. Nonetheless, sugarcane syrups with lower mineral levels can be considered nutritionally adequate.

Physical durability and insecticidal activity of long-lasting insecticidal nets in Cruzeiro do Sul, Brazil

Vector control is one of the principal strategies used for reducing malaria transmission. Long-lasting insecticidal bed nets (LLINs) are a key tool used to protect populations at risk of malaria, since they provide both physical and chemical barriers to prevent human-vector contact. This study aimed to assess the physical durability and insecticidal efficacy of LLINs distributed in Cruzeiro do Sul (CZS), Brazil, after 4 years of use. A total of 3000 LLINs (PermaNet 2.0) were distributed in high malaria risk areas of CZS in 2007. After 4 years of use, 27 ‘rectangular’ LLINs and 28 ‘conical’ LLINs were randomly selected for analysis. The evaluation of physical integrity was based on counting the number of holes and measuring their size and location on the nets. Insecticidal efficacy was evaluated by cone bioassays, and the amount of residual insecticide remaining on the surface of the LLINs was estimated using a colorimetric method. After 4 years of use, physical damage was highly prevalent on the rectangular LLINs, with a total of 473 holes detected across the 27 nets. The upper portion of the side panels sustained the greatest damage in rectangular LLINs. The overall mosquito mortality by cone bioassay was < 80% in 25/27 rectangular LLINs, with panel A (at the end of the rectangular bednet) presenting the highest mortality (54%). The overall mean insecticide concentration was 0.5 µg/sample, with the bednet roof containing the highest average concentration (0.61 µg/sample). On the conical LLINs, 547 holes were detected, with the bottom areas sustaining the greatest damage. The cone bioassay mortality was < 80% in 26/28 of the conical LLINs. The mean insecticide concentration was 0.3 µg/sample. After 4 years of use, the insecticidal efficacy of the LLINs was diminished to below acceptable thresholds.

Study on the behavior of radionuclides in geologic samples from fault zone, Gabal Um Hamd, southwestern Sinai, Egypt

The present study concerned with the activity concentrations of natural radionuclides (238U, 234U, 230Th, 226Ra, 232Th, 40K and, 235U) in ten sedimentary rock samples collected from fault zone, Gabal Um Hamd, southwestern Sinai, Egypt. These samples were investigated to study their behavior during a part of geologic time. The activity concentrations were measured using γ-ray spectrometry (HPGe detector). The investigated samples were analyzed for major oxides using the XRF technique. The results demonstrated high average activity concentrations of 238U, 234U, 230Th, 226Ra, 232Th, 40K and, 235U than the worldwide average values as reported by UNSCEAR 2008. Theil diagram showed that there are accumulation and leaching of uranium in some samples in the two sides of the fault zone. It is noticed that the ages of uranium depositions for the samples collected from the downthrown of the fault zone vary from 121.5 to 440.1 ky, while for the sample collected from the upthrown of the fault is 210.9 ky. The 230Th/232Th activity ratios range between 4.55 and 91.04 for downthrown samples and between 4.75 and 6.05 for upthrown samples which are smaller than 20 except for two samples, indicating a contamination of the samples by detrital 230Th. After subtraction of the detrital 230Th, the corrected ages for downthrown samples vary from 119.1 to 231.7 ky while for upthrown samples vary from 164.4 to 390 ky.

Application of non-lethal bioSPME-LC-MS/MS for the detection of human pharmaceuticals in soft corals: A survey at the North Nilandhe atoll (Maldives)

At present the information regarding the occurrence of human pharmaceuticals (PhaCs) in coral reefs and their potential impacts on the associated fauna is limited. To optimize the collection of data in these delicate environments, we employed a solid-phase microextraction (bioSPME) and liquid chromatography coupled to tandem mass spectrometry (LC-MS/MS) procedure that enabled in vivo determinations in soft corals. Specifically, we researched the antibiotics Ofloxacin Sulfamethoxazole and Clarithromycin, the anti-inflammatory Diclofenac Propyphenazone Ketoprofen and Amisulpride, the neuroactive compounds Gabapentin-lactam, the beta-blocker Metoprolol and the antiepileptic Carbamazepine. Reproducibility was between 2.1% and 9.9% and method detection limits LODs) were between 0.2 and 1.6 ng/g and LOQs between 0.8 and 5.4 mg/g. The method was then applied to establish a baseline for the occurrence of these compounds in the Maldivian archipelago. Colonies of Sarcophyton sp. and Sinularia sp. were sampled along an inner-outer reef transect. Five of the ten targeted PhaCs were identified, and 40% of the surveyed coral colonies showed the occurrence of at least one of the selected compounds. The highest concentrations were found inside the atoll rim. Oxoflacin (9.5 ± 3.9 ng/g) and Ketoprofen (4.5 ± 2.3 ng/g) were the compounds with the highest average concentrations. Outside the atoll rim, only one sample showed contamination levels above the detection limit. No significant differences were highlighted among the two surveyed soft coral species, both in terms of average concentrations and bioconcentration factors (BCFs).

Spatial modeling of air pollution in Kharkiv city

&#x0D; &#x0D; &#x0D; One of the most pressing problems facing cities, which negatively affects public health. There is a global practice of online monitoring of the content of pollutants in the air of settlements and informing the population about dangerous periods of increased pollution concentrations for certain categories of diseases and the population as a whole. It is also likely that one of the factors of pollution spread is the landscape differentiation of the city’s territory. The purpose of the study presented in this article is to develop statistical and cartographic models of the spatial distribution of air pollutants within the city of Kharkiv and to establish the relationship between the degree of air pollution and types of urban landscapes. Methods. Based on the analysis of the main methodological approaches and tasks of cartographic modeling of the spatial distribution of air pollution, the study substantiates the choice of the modeling method in this study; the features of a large city as an object of cartographic modeling of air pollution are assessed. Results. Based on the results of long-term monitoring by the Kharkiv Regional Center for Hydrometeorology, a statistical analysis of the results of the maximum and average content of pollutants in the atmosphere of Kharkiv was made and the spatial distribution of air pollution in Kharkiv (including (dust, carbon monoxide, nitrogen dioxide, sulfur dioxide, formaldehyde) was modeled, and patterns of pollution distribution were identified according to landscape types. Conclusions. In general, the spatial analysis of pollutant concentrations in the territories of Kharkiv showed that, in terms of maximum concentrations, the southeastern part of Kharkiv is most affected by carbon monoxide, nitrogen dioxide, and formaldehyde. The reason for this is the large area of industrial facilities. The northwestern part of the city has the highest concentrations of dust and sulfur dioxide. There is a lowering of the relief in the floodplain type of landscape and dense development. Intensive traffic and lowered relief (floodplain landscape) cause high average concentrations of dust, carbon monoxide, and sulfur dioxide in the southern part of the city. Nitrogen dioxide concentrations exceed the TLK in the northwest. The reason is the lowering of the relief on the outskirts of the city (floodplain landscape). The central part of the city has a high average concentration of formaldehyde. In general, a pattern of high concentrations of pollutants was found on the floodplains of the Lopan and Kharkiv rivers, with the lowest concentrations confined to watershed types of terrain between the Kharkiv and Lopan rivers and the Udy and Lopan rivers.&#x0D; &#x0D; &#x0D;

Characteristics and Risk Assessment of Antibiotic Contamination in Oujiang River Basin in Southern Zhejiang Province

Antibiotic pollution in the environment has a negative impact on ecosystem security. Taking the Oujiang River Basin as an example,high-performance liquid chromatography mass spectrometry(LC-MS)was used to detect the concentration of six classes of 35 antibiotics in the surface water of the southern Zhejiang River Basin. The concentration level and spatial distribution of antibiotics were analyzed,the risk of antibiotics to ecology and human health were assessed using relevant models,and the sources of antibiotics were discussed. The results showed that in 20 sampling sites,a total of four classes of 12 antibiotics were detected,including sulfonamides,quinolones,tetracyclines,and lincosamides. The total concentration was ND-1 018 ng·L-1. The highest detection rate was that of Lincomycin(90.48%),followed by that of sulfapyridine(38.10%). The three antibiotics with the highest average concentrations were ofloxacin(12.49 ng·L-1),Lincomycin(11.08 ng·L-1),and difloxacin(7.38 ng·L-1). Antibiotics in the basin showed mainly spotty pollution,which had large spatial differentiation. The average concentration of antibiotics in the upstream(54.39 ng·L-1)was higher than that mid-downstream(46.64 ng·L-1). The degree of antibiotic pollution from upstream to downstream showed a characteristic of being "sparse in the upstream and dense in the downstream. " This indicated that the concentration of antibiotics in the upstream was significantly different,whereas the pollution degree of antibiotics in the downstream was uniform. The upstream was mainly polluted by health,livestock,and poultry breeding wastewater emissions,and downstream pollution was mainly caused by densely populated activities and the rapid development of economy,trade,and industry. The ecological risk assessment results showed that the upstream site H6 had the highest risk quotient,ofloxacin and enrofloxacin had high risk levels, and lincomycin had a moderate risk level. Health risk assessment results showed that the Oujiang River surface water antibiotics posed no risk to human health.

Evaluating the retention of airborne microplastics on plant leaf: Influence of leaf morphology

Airborne microplastics (AMPs) have been identified in both indoor and outdoor environments and account for a large portion of an individual's daily exposure to microplastics. Thus, it is crucial to find effective methods to capture and control the levels of AMPs and ultimately reduce human exposure. While terrestrial plants have been recognized for their effectiveness in capturing airborne particles, little is known about their ability to capture AMPs. This study investigated the ability of 8 natural plant species and 2 artificial plants to capture AMPs, as well as the influence of leaf morphology on this retention. Plant leaves were exposed to AMPs for two weeks, and deposited AMPs were characterized using a Micro-Fourier Transform Infrared (μ-FTIR)spectroscopy. Selected cleaned leaves were further digested, and the presence of subsurface AMPs was confirmed using μ-Raman spectroscopy. Results revealed that AMPs were retained on the leaves of all selected plant species at concentrations ranging from 0.02 to 0.87 n/cm2. The highest average concentration was observed on an artificial plant with fenestrated leaves, followed by natural plant species with trichomes and leaflets. The lowest concentration was observed on a natural plant with smooth leaves. The majority (90%) of retained AMPs were fibres, and the remaining were fragments. Polyethylene terephthalate (PET) was the prominent polymer type. Additionally, AMP fragments were observed in the leaf subsurface in one selected species, likely retained within the leaf cuticles. The results suggest that plant leaves can indiscriminately retain AMPs on their surfaces and act as temporary sinks for AMPs. Additionally, indoor plants may provide a useful functional role in reducing indoor AMP concentrations, although longer-term studies are needed to ascertain their retention capacity more accurately over time and to evaluate the capability of indoor plants to act as a suitable, cost-effective candidate for reducing AMPs.

Monitoring, exposure and risk assessment of formaldehyde in alcoholic beverages in Korea

Formaldehyde occurs naturally in food and alcoholic beverages. Formaldehyde and alcoholic beverages can cause various health problems, including irritation of the eyes, nose, and throat, respiratory problems, and skin rashes. Alcoholic beverage samples (N = 236) were collected and analyzed for formaldehyde by liquid chromatography-tandem mass spectrometry. The highest average concentrations were detected in fruit wines (1.71 µg/g), followed by wines (1.15 µg/g), cheongju (0.95 µg/g), soju (0.85 µg/g), takju (0.64 µg/g) and beers (0.61 µg/g). We assessed the exposure and risk assessment to formaldehyde from alcoholic beverages based on the monitoring data for the general population and consumers in Korea using various schemes for point estimation. The daily intakes of formaldehyde for the general population and consumers were estimated to be 83 µg and 1202 µg, respectively. The mean hazard indexes (HI) for the general population and consumers in Korea were 0.009 and 0.132, respectively. On the other hand, the mean hazard indexes (HI) for the general population and consumers in Korea were 0.009 and 0.132, respectively. The exposure to formaldehyde in these alcoholic beverages for the Korean population was shown to be of low concern, but it is necessary to monitor the level of formaldehyde in alcoholic beverages and continuously conduct exposure assessment for consumers.

Heavy metal accumulation and health risk assessment in S. alterniflora Loisel. and native plant Suaeda salsa (L.) Pall. in Dongtai Tiaozini wetland

Coastal wetlands play an irreplaceable role in the global ecosystem, and both human activities and natural factors may lead to the contamination of Tiaozini coastal wetland with heavy metals. The study was conducted to determine the contents of eight heavy metals, Hg, Cd, Cr, As, Pb, Cu, Ni, and Zn, in the above-ground and below-ground parts of the plants and in the rhizosphere sediment, using the invasive species S. alterniflora and the native plant S. glauca, calculating the geoaccumulation index (Igeo), bioaccumulation factor, transfer factor, total target risk quotient (TTHQ), and carcinogenicity risk (CR), to analyze the transfer characteristics and potential health risks to human beings of the heavy metals in plants. This study aims to investigate the enrichment characteristics of the dominant plant, S. alterniflora Loisel. (S. alterniflora) and Suaeda salsa (L.) Pall. (S. glauca). Regarding heavy metals, eight common heavy metal elements were selected, including Hg, Cd, Cr, As, Pb, Cu, Ni, and Zn, and examined their content in surface sediments and different parts of the two plants. The transfer characteristics of heavy metals in the plant body and their potential health risks to humans were also analyzed. These findings suggest that both plants accumulate higher concentrations of heavy metals in their below-ground parts. Cr, Cu, and Zn had the highest average concentrations in both plants. Geoaccumulation index (Igeo) indicated that the Tiaozini Wetland is not yet contaminated. S. alterniflora had transfer factors less than 1 for all heavy metals, while S. glauca had transfer factors greater than 1. Both plants had a certain purifying effect on heavy metal pollution in wetlands, including Cr, Cd, Cu, and Zn. However, Cr and As in the below-ground part of S. alterniflora and Cr in the above-ground part of S. glauca had a target hazard quotient (THQ) greater than 1, indicating a potential health risk to humans, but the carcinogenic risk is low. For other heavy metals, THQ was less than 1, indicating no health risk. The total target hazard quotient (TTHQ) of different parts of both plants was greater than 1, which must be taken into account when considering their suitability as edible resources.

Per- and poly-fluoroalkyl substances removal in multi-barrier advanced water purification system for indirect potable reuse.

The study evaluated the removal efficacy of per- and poly-fluoroalkyl substances (PFAS) across various advanced water treatment (AWT) processes in a field-scale AWT train using secondary effluent samples from a full-scale water reclamation facility (WRF). Samples collected from April to October 2020 revealed PFCAs as the dominant PFAS compounds in the WRF secondary effluent, with PFPeA having the highest average concentration and PFSAs in notably lower amounts. Temporal fluctuations in total PFAS concentrations peaked in September 2020, which may reflect the seasonality in PFAS discharges related to applications like AFFFs and pesticides. In assessing AWT processes, coagulation-flocculation-clarification-filtration system showed no notable PFAS reduction, while ozonation resulted in elevated PFBS and PFBA concentrations. Biological activated carbon (BAC) filtration effectively removed long-chain PFAS like PFOS and PFHxS but saw increased concentrations of short-chain PFAS post-treatment. Granular activated carbon (GAC) filtration was the most effective treatment, reducing all PFSAs below the detection limits and significantly decreasing most PFCAs, though short-chain PFCAs persisted. UV treatment did not remove short-chain PFCAs such as PFBA, PFPeA, and PFHxA. The findings highlight the efficacy of AWT processes like GAC in PFAS reduction for potable reuse, but also underscore the challenge presented by short-chain PFAS, emphasizing the need for tailored treatment strategies. PRACTITIONER POINTS: Secondary effluents showed higher concentrations of PFCAs compared to PFSAs. Advanced water treatment effectively removes long-chain PFAS but not short-chain. Ozonation may contribute to formation of short-chain PFAS. BAC is less effective on short-chain PFAS, requiring further GAC treatment.

Uranium Isotope Characterization in Volcanic Deposits in a High Natural Background Radiation Area, Mamuju, Indonesia

Mamuju is an area of high natural radiation in Indonesia with high natural radiation levels (average 613 nSv h−1). Mamuju is anomalous due to its high average 238U and 232Th concentrations of 22,882 and 33,549 Bq kg−1, respectively, in laterite and rock. High natural radionuclide concentrations of 238U, 232Th, and 40K have also been reported in soil samples from several locations in Mamuju, including Botteng, Northern Botteng, Takandeang, Ahu, and Taan. High radiation levels are related to radioactive mineral occurrences in the Adang volcanic complex, comprised of phonolitoid and foiditoid lithologies. According to the International Atomic Energy Agency (IAEA), uranium deposits can be classified into several types, among them a volcanic-related deposits, which include three sub-types: stratabound, structure-bound, and volcano-sedimentary deposits. This study aims to characterize volcanic rock deposit sub-types in the Mamuju area based on uranium radioisotope measurements. The uranium isotopes were measured using a tandem quadrupole inductively coupled plasma mass spectrometer combined with chemical separation by extraction chromatography using UTEVA resin. The analytical results for the 234U/238U ratios are used to determine the formation characteristics of minerals in each deposit sub-type based on mineral formation age, post-formation processes, and disturbances that affected the formation processes. Based on geochronological calculations using 234U/238U mineralization age, the deposits in the Mamuju area are 0.914–1.11 million years old and are classified as recent mineralization. These data have important implications for tracing uranium source rocks in the Mamuju area and may explain the anomalously high radiation levels in the Mamuju area.

Gallium and Germanium in Pennsylvanian Coals, Shales, and Paleosols in Indiana

Gallium (Ga) and germanium (Ge) are two elements of high industrial interest, included in the current United States and European Union lists of critical raw materials. This paper compares Ga and Ge concentrations between coals and associated paleosols and shales in Indiana. In addition, we include Ga and Ge data on the coal waste from coal preparation plants (coal tailings) to evaluate the coal tailings as potential sources of these elements. Paleosols have an average Ga content of 26.70 ppm, more than shales with an 18.77 ppm average, and coals with a 4.61 ppm average. The Springfield coal tailings average 15.60 ppm of Ga and the Brazil and Staunton Formation coal tailings average 31.90 ppm. For Ge, the coals have the highest average concentration (6.46 ppm), then shales (1.36 ppm), and paleosols (0.96 ppm). In coal tailings, the average Ge concentration is 13.90 ppm for the Springfield and 47.70 ppm for the Brazil and Staunton Formation coal waste. For Ga, a very strong positive correlation was obtained with aluminum (Al) in paleosols (R2=0.89) and coal tailings. A strong correlation was also obtained for shales (R2=0.86), together indicating that Al content is a great predictor of Ga concentrations in these materials. For Ge, there seems to be a tendency of decreasing Ge concentration with an increase in Al content in coals, suggesting an organic and not mineral association for this element. The organic association is also supported by a strong negative correlation between Ge and ash yield in coal tailings.

Distribution of toxic and trace metals in fish from the Black Sea: Implications for human health risks

This study focused on the investigation of toxic and trace metal levels in fish caught from the Black Sea, which is facing pollution threats from various human activities. It also aimed to assess the potential health risks associated with consuming fish and contribute to the development of strategies for sustainable fisheries management. Metal presence was observed in the muscle tissues of four commercially consumed fish species (anchovy, whiting, horse mackerel and red mullet) from nine different stations in the Black Sea. Among the metals, the highest average concentration was observed for aluminium (Al) in anchovy and the lowest concentration for cadmium (Cd) in whiting. However, the levels were generally below the maximum allowable limits recommended by the FAO, WHO, EC, and Turkish Food Codex. The study results showed that metal concentrations in the analyzed fish species did not pose significant non-carcinogenic health risks to consumers. Although research findings show that some fish species studied from the Black Sea exhibit high metal levels, the concentrations of toxic and trace elements are generally within acceptable thresholds for safe fish consumption. The findings of this study are thought to help stakeholders develop strategies for environmental protection and sustainable fisheries management in the region.

Effects of grain size and temperature on slip and twinning activity in a magnesium-rare earth alloy

Understanding the deformation mechanisms in magnesium alloys is critical to develop the next-generation high-performance magnesium alloys. In this work, the effects of grain size and temperature on slip and twinning activities in WE43 magnesium-rare earth alloy were investigated with the quasi-in-situ electron backscattering diffraction method and slip trace analysis. Compression tests were conducted for the samples with three different grain sizes at room temperature (RT) and liquid nitrogen temperature (LNT), respectively. More pyramidal slips were activated in the fine-grained sample to accommodate the plastic strain instead of more twins generated in the coarse-grained sample, which contributed to its higher strain to failure and strain hardening rate. Numerous individual twins with thin structures formed in the fine-grained sample, while thick twins were observed in the coarse-grained sample. The numerous thin twins and high activities of pyramidal slips in the fine-grained sample would be attributed to the high kernel average misorientation (KAM) value and local stress concentration around grain boundaries. Regarding temperature effects, more thin twins and twin-twin interactions were observed at LNT than at RT, and the KAM value was high around these twin boundaries, which contributed to enhancing the flow stress but reducing the strain to failure at LNT.

Occurrence Assessment of Pharmaceuticals in Various Sewage Treatment Plants and Effluent-Receiving Streams in Korea

The occurrence of micropollutants, including pharmaceuticals, personal care products, pesticides, and hormones in various aquatic ecosystems is a matter of grave concern due to their possible repercussions on human and wildlife endocrine systems. The wastewater containing pharmaceuticals from various sites is usually introduced to sewage treatment plants (STPs); therefore, monitoring of pharmaceuticals in STPs is crucial. In this study, we determined the occurrence of 58 pharmaceuticals in the influent and effluent of 13 STPs based on regional and linked wastewater differences and investigated their removal rates. Furthermore, we assessed the contribution rates of some STP effluents on pharmaceutical concentration in the upstream and downstream areas of the discharge source. Different kinds of pharmaceuticals were measured in the STPs. The top five pharmaceuticals with high concentrations in the influent of each STP were similar due to the dominance of domestic sewage in the influent. The average concentration of acetaminophen, caffeine, acetylsalicylic acid, naproxen, and ibuprofen in the influent of the STPs was higher than that of other pharmaceuticals, and their removal was 94–100%. In contrast, iopamidol, cimetidine, diphenhydramine, and carbamazepine showed a high average concentration in the effluent. The monitoring results of nine streams near STPs indicated that the effluent could contribute to the increase in the types of pharmaceuticals in the receiving streams. The detected pharmaceuticals’ types were 9–29 and 17–33 in the upstream and downstream areas, respectively, of STP discharge channels. Based on flowrate data, the contribution rate of the STP effluent on the stream was −69–326%.