Deposition Of Trace Elements Research Articles

Aerosol trace element solubility and deposition fluxes over the Mediterranean Sea and Black Sea basins

Abstract. Aerosol samples collected during summer 2013 on GEOTRACES cruise GA04 in the Mediterranean and Black seas were analysed for their soluble and total metal and major ion composition. The fractional solubilities (soluble divided by total concentrations) of the lithogenic elements (Al, Ti, Mn, Fe, Co and Th) varied strongly with atmospheric dust loading. Solubilities of these elements in samples that contained high concentrations of mineral dust were noticeably lower than at equivalent dust concentrations over the Atlantic Ocean. This behaviour probably reflects the distinct transport and pollutant regimes of the Mediterranean basin. Elements with more intense anthropogenic sources (P, V, Ni, Cu, Zn, Cd and Pb) had a variety of largely independent sources in the region and generally displayed higher fractional solubilities than the lithogenic elements. Calculated dry-deposition fluxes showed a west-to-east decline in the N/P ratio in deposition over the Mediterranean, a factor that contributes to the P-limited status of the eastern basin. Atmospheric deposition may make a significant contribution to the surface water budgets of Mn and Zn in the western Mediterranean.

Organic trace elements enhance growth performance, antioxidant capacity, and gut microbiota in finishing pigs

Excessive inorganic trace elements are added to livestock and poultry feed to meet the needs of animals, accompanied by frequent occurrence of excretion and gastrointestinal stress. Replacing inorganic trace elements with organic trace elements provides a promising solution to alleviate these problems. Therefore, this study aimed to assess the impact of replacing all inorganic trace elements (ITMs) in feed on the growth performance, meat quality, serum parameters, trace element metabolism, and gut microbiota of finishing pigs. A total of 128 Duroc × Landrace × Yorkshire growing-finishing pigs (33.88 ± 0.62 kg) were assigned to four treatments in a randomized complete block design. Each treatment was divided into four replicates, each containing eight pigs. The control group received a basal diet containing 100% inorganic trace elements, while the experimental groups were provided with diets where all inorganic trace elements were substituted with 30, 50, and 70% organic trace elements. The experiment spanned 56 days. Results indicated that replacing all ITMs with 30, 50, and 70% OTMs demonstrated no adverse effects on average daily feed intake, average daily gain, feed conversion ratio, eye muscle area, backfat thickness, and relative organ weight of finishing pigs compared to the control group. Furthermore, the replacement led to increased serum immunoglobulin A concentration and Cu-SOD enzyme activity, and decreased serum MDA level, and GSH-Px activity in the liver. Notably, 50 and 70% OTMs increased serum Mn-SOD activity, and 70% OTMs increased serum T-AOC content. Moreover, it significantly decreased the excretion of trace elements in feces without compromising their deposition in the muscle. Additionally, replacing 100% ITMs with 30% OTMs resulted in an improved Shannon index of colonic microbiota in finishing pigs. In conclusion, replacing 100% inorganic trace elements with 30, 50, and 70% organic trace elements exhibited no detrimental effects on the performance of finishing pigs. In conclusion, replacing 100% inorganic trace elements with 70% organic trace elements had certain potential to improve the production performance of finishing pigs. This replacement strategy can enhance meat quality, boost antioxidant capacity, reduce trace element excretion, facilitate trace element absorption and deposition, and enhance gut microbiota homeostasis.

Moss Technique Used to Monitor the Atmospheric Deposition of Trace Elements on the Territory of the Ryazan Region, Russia

Instrumental neutron activation analysis in combination with the method of moss biomonitoring for the assessment of atmospheric deposition of heavy metals and other elements was applied for the first time in the Ryazan Region in Russia. Concentrations of 42 macro, micro and trace elements in 63 moss samples (Hylocomium splendens and Pleurozium schreberi, as well as Hypnum cupressiforme, Sciuro-hypnum sp., Plagiothecium sp. and Ptilium sp.), collected on a relatively uniform grid in the study area, were determined. On the basis of analytical results using GIS technologies, maps of the spatial distribution of heavy metals and other toxic elements were constructed for the Ryazan region. The method of multivariate statistical analysis (factor analysis) was used to identify the main sources of pollution—large industrial facilities located in this region. The obtained results were included in the Atlas of Atmospheric Deposition of Heavy Metals, which is published by the UN Commission on Long-Range Transboundary Air Pollution (UNECE ICP Vegetation).

Winter atmospheric deposition of trace elements in the Arkhangelsk region (NW Russia): Insights into environmental effects

Atmospheric precipitation is an important indicator of ecological status. Snow cover accumulates all atmospheric precipitation that occurs during the cold season and releases large amounts of matter into surface water streams during spring snowmelt. We measured chemical composition of suspended solids (>0.45 μm) and dissolved matter (<0.45 μm) of atmospheric precipitation sampled on a monthly basis in 4 stations of Arkhangelsk region in cold seasons of 2018–2021. The fluxes of insoluble particles increase consistently in the spring months. In winter, the largest fluxes of suspended solids from the atmosphere were observed in the urbanized areas (in Severodvinsk and Onega). Snow in Onega showed a significant enrichment in Mn as well as Rb, Sr, Cs, Ba and Pb, which is related to boiler house emissions. Severodvinsk snow is enriched in V, Ni in dissolved fraction and Al, V, Cu, Sr, Pb in suspended solids. The environmental risk assessment shows that Onega station is affected to high and extremely polluted conditions for Mn concentration and Severodvinsk station is affected to multi-element pollution from moderate to significant levels. Comparison with the composition of the river runoff of the Northern Dvina showed that the concentrations of Cu, Zn, Cd and Pb in the snow are equal to or even higher than the river concentrations, indicating that atmospheric precipitation accumulated during winter can significantly affect the geochemistry of river runoff with respect to these elements.

Lung deposition of PM-bound trace elements and corresponding human health risk assessment in commercial kitchens serving Mediterranean cuisine

The service offered by commercial kitchens and the catering industry is becoming more and more popular all around the world. However, the health risks of sector workers are often overlooked. In this study, size-segregated Particulate Matter (PM) samples were collected from the indoor environments of five commercial kitchens, and elemental concentrations were quantified to estimate the corresponding health risks. Lung-deposited fractions of trace elements in three different regions of the respiratory tract were estimated and used to assess carcinogenic and non-carcinogenic health risks. Besides, the deterioration in lung capacity of the cooks was also evaluated by spirometry tests to correlate indoor pollutants. Exposure to trace elements was dominated by Na, S, Al, Fe, and Mg. Estimated carcinogenic risk through inhalation exposure to Cr was between the moderate risk level of 10−6 to 10−4, while the Hazard Index (HI) values were lower than the acceptable level of 1. This, along with elevated indoor PM levels, represented a significant potential for carcinogenic health hazards for the kitchen staff. According to the results of the lung function tests, a significant decrease was determined in the respiratory functions of the cooks, and it was associated with elevated exposure to fine PM, Pb, Cr, Cu, K, Ni, and Mn. Workplace health and safety measures to better protect the health of kitchen staff are urgently needed and should attract more public attention.

Uncovering sources, distribution, and seasonal patterns of trace element deposition: the elemental puzzle of the western Himalayas.

The transport and deposition of atmospheric pollutants in the Himalayas have a adverse impact on the climate, cryosphere, ecosystem, and monsoon patterns. Unfortunately, there is a insufficiency of data on trace element concentrations and behaviors in the high-altitude Himalayan region, leading to limited research in this area. This study presents a comprehensive and detailed comprehension of trace element deposition, its spatial distribution, seasonal variations, and anthropogenic signals in the high-altitude Kashmir region of the Western Himalayas. Our investigation involved the analysis of 10 trace elements (Al, Cr, Mn, Fe, Co, Ni, Cu, Zn, Cd, and Pb) in glacier ice, snow pits, surface snow, and rainwater collected at various sites including Kolahoi, Thajwas, Pahalgam (Greater Himalayan ranges), and Kongdori and Shopian (Pir Panjal Ranges) during 2021.The study reveals distinct ranges of concentrations for the trace elements at different sampling sites. Our analysis of trace element concentration depth profiles in snow pits reveals seasonal fluctuations during the deposition year. The highest concentrations were found in the autumn(below 20cm) and summer (top layer), compared to the winter concentration (10-20cm). The high enrichment factors (EFs) suggest the severity of human-induced trace metal deposition in the western Himalayan region, relative to surrounding regions. Surprisingly, the concentrations and EFs of trace elements showed seasonal contradictions, with lower concentration values and higher EFs during the non-monsoon season and vice versa. A source apportionment analysis using the positive matrix factorization (PMF) technique identified five sources of trace element deposition in the region, including crustal sources (32.33%), coal combustion (15.62%), biomass burning (17.63%), traffic emission (18.8%), and industrial sources (15.6%). Additionally, the study incorporated backward trajectories coupled with δ18O using the NOAA HYSPLIT model to estimate moisture sources in the region, which suggests atmospheric pollutants predominately deposited from the large-scale atmospheric circulation from westerlies (75%) during non-monsoon season. These findings underscore the urgent need for enhanced monitoring and research efforts in the future.

Moss as a Biomonitor to Identify Atmospheric Deposition of Minor and Trace Elements in Macedonia

The present work was carried out to obtain and highlight the fifth comprehensive baseline dataset on atmospheric deposition of trace elements and to assess air quality in Macedonia. In the period from August to September 2020, a total of 72 moss samples were collected in accessible areas in the country. The content of 28 elements (Ag, Al, B, Ba, Ca, Cd, Co, Cr, Cu, Fe, Ga, Hg, K, La, Mg, Mn, Mo, Na, Ni, P, Pb, S, Sb, Sc, Sr, Ti, U, and Zn) was determined using inductively coupled plasma–mass spectrometry. Based on the data obtained on the content of the elements, a factor analysis was carried out to identify and characterise different sources of pollution. In addition, distribution maps were created for all elements to show the regions most affected by anthropogenic activities. The survey conducted in 2020 has shown that air pollution with potentially toxic elements (PTEs) has slightly decreased compared to the results of the previous survey from 2015. This is due to the fact that, despite the operation of all mining and smelting facilities with the same capacity, government regulations for the installation of cleaning systems and additional regulations to reduce pollution have been introduced in the last five years. Nevertheless, the fact remains that the highest anthropogenic air pollution with PTEs is still caused by the operation of the ferronickel smelter in Kavadarci (Ni and Cr) in the southern part and by the lead and zinc mines in Probištip, Makedonska Kamenica, and Kriva Palanka in the eastern part of the country (Cd, Pb, and Zn).

Influences of sources and weather dynamics on atmospheric deposition of Se species and other trace elements

Abstract. Atmospheric deposition is an important source of the micronutrient selenium for terrestrial ecosystems and food chains. However, the factors determining the total concentrations and chemical forms (speciation) of selenium in atmospheric deposition remain poorly understood. Here, aerosol samples were collected weekly over 5 years at Pic du Midi Observatory (French Pyrenees), alongside highly temporally resolved samples of aerosols, precipitation, and cloud water taken during a 2-month campaign. Firstly, measurements of selenium, other elements, and water isotopes were combined with sophisticated modelling approaches (aerosol–chemistry–climate SOCOL-AERv2 model and air parcel backward trajectories and Lagrangian moisture source analyses). Aerosol selenium measurements agreed well with SOCOL-AERv2-predicted values, and interestingly, higher fluxes of selenium and other elements were associated with deep convective activity during thunderstorms, highlighting the importance of local cloud dynamics in high deposition fluxes. Our results further indicate the coupling of element and water cycles from source to cloud formation, with decoupling during precipitation due to below-cloud scavenging. Secondly, selenium speciation was investigated in relation to sulfur speciation, organic composition, and moisture sources. While in the 5-year aerosol series, selenite (SeIV) was linked to anthropogenic source factors, in wet deposition it was related to pH and Atlantic moisture sources. We also report an organic selenium fraction, tracing it back to a marine biogenic source in both aerosols and wet deposition. With a comprehensive set of observations and model diagnostics, our study underscores the role of weather system dynamics alongside source contributions in explaining the atmospheric supply of trace elements to surface environments.

Source and respiratory deposition of trace elements in PM2.5 at an urban location in Dhaka city

Air pollution has been creating severe environmental crises in Dhaka. This city ranks at the top among the major cities of the world. A multidimensional study is needed to assess the severity of this crisis. This study aims to determine the sources of trace elements in PM2.5 and their effects on health. We measured concentrations of 15 trace elements in PM2.5 every hour for eight days using a well-equipped mobile air quality monitoring system integrated with an automatic sampling system (AQMS, Horiba, Japan). We analyzed the concentrations of the trace elements to identify their potential sources and diurnal variation and to compute the respiratory deposition dose of the trace elements to estimate the health risks they pose. The daily average concentration of PM2.5 was higher than the allowable limit set by the World Health Organization (WHO). Among the trace elements, sulfur had the highest concentration and vanadium was the lowest. We found out that concentrations of the elements were the highest during the middle of the day and the lowest during midnight. Four source profiles of PM2.5 were identified by positive matrix factorization (PMF). Soil dust with sulfur-rich petroleum contributed about 65 %, industrial and non-exhaust emissions about 5 % each, and heavy engine oil combustion about 25 % to air pollution. Air mass backward trajectory analysis indicated that Dhaka's air contains both local and transboundary pollution. According to the determined respiratory deposition dose of the elements, males had higher deposition than females during heavy exercise. Sulfur and vanadium have the highest and lowest respiratory deposition dose, respectively. The highest amount of deposition occurred in the upper airways. We expect that this study will help professionals develop effective strategies to prevent and mitigate the emission of air pollutants.

Preface to the inter-journal special issue “RUSTED: Reducing Uncertainty in Soluble aerosol Trace Element Deposition”

Preface to the inter-journal special issue “RUSTED: Reducing Uncertainty in Soluble aerosol Trace Element Deposition”

Effects of a manganese complex with lysine and glutamic acid on growth performance, manganese deposition, and emission, antioxidant capacity and metacarpal strength in weaned piglets.

The present study sought to assess the effects of manganese complexes with lysine and glutamic acid (Mn-LG) as manganese (Mn) sources on growth performance, trace element deposition, antioxidant capacity, and metacarpal strength in weaned piglets. The study involved 288 healthy Duroc × Landrace × Yorkshire piglets that were weaned at 25 to 28 d of age and weighed 8.66 ± 0.96kg. These piglets were randomly divided into six groups: a control group (Mn-LG-0, receiving a basal diet without Mn supplementation), a Mn sulfate group (basal diet supplemented with 40 mg·kg-1 diet of Mn, Mn-S-40 group), and four Mn-LG groups (Mn-LG-20, Mn-LG-40, Mn-LG-60, Mn-LG-80, supplemented with 20, 40, 60, and 80 mg·kg-1 Mn from Mn-LG in the basal diet). Grouping began at weaning on the 0th day of the experiment. The corn-soybean-based basal diet during the early (days 0 to 14) and late (days 15 to 42) phases of the experiment contained 20.88 and 30.12 mg·kg-1 Mn, respectively. Blood samples were collected on days 14 and 42, and pigs were sacrificed for sample collection on day 42. The results indicated no significant differences in average daily gain, average daily feed intake, or feed-to-gain ratio among the groups (P > 0.05). The diarrhea rates of all Mn-LG groups and the Mn-S-40 group were significantly lower in the 0 to 14 d and during the entire experimental period than in the Mn-LG-0 group (P < 0.001). The Mn-LG-40 group exhibited a significant increase in liver Mn concentration and serum Mn superoxide dismutase (Mn-SOD) activity on day 42 (P < 0.01), as well as a significant decrease in fecal Mn concentration (P < 0.05), compared to those of the Mn-S-40 group. Significant differences (P < 0.05) were detected in the serum, liver, and fecal Mn concentrations, as well as in the serum and liver Mn-SOD activity, across the different Mn-LG groups. The serum and fecal Mn concentrations and serum Mn-SOD activity increased linearly or quadratically (P < 0.01) with increasing Mn-LG supplementation. No significant differences (P > 0.05) were found in kidney, heart, or metacarpal bone Mn concentrations or in bone strength indices. In summary, compared with the Mn-LG-0 diet, dietary supplementation with Mn-LG enhanced serum Mn deposition and Mn-SOD activity and decreased the incidence of diarrhea. Additionally, the fecal Mn concentration was lower in the Mn-LG group than in the inorganic group at equivalent dosages.

Response of trace elements in urban deposition to emissions in a northwestern river valley type city: 2010–2021

Anthropogenic activities release significant quantities of trace elements into the atmosphere, which can infiltrate ecosystems through both wet and dry deposition, resulting in ecological harm. Although the current study focuses on the emission inventory and deposition of trace elements, their complex interactions remain insufficiently explored. In this study, we employ emission inventories and deposition data for eight TEs (Cr, Mn, Ni, Cu, Zn, As, Cd, Pb) in Lanzhou City to unveil the relationship between these two aspects. Emissions in Lanzhou can be roughly divided into two periods centered around 2017. Preceding 2017, industrial production constituted the primary source of TEs emissions except for As; coal combustion was the primary contributor to Cr, Mn, and As emissions; waste incineration played a significant role in As, Zn, and Cd emissions; biomass combustion influenced Cr and Cd emissions; and transportation sources were the predominant contributors to Pb and Cu emissions. With the establishment of waste–to–energy plants and the implementation of ultra–low emission retrofits, emissions from these sources decreased substantially after 2017. Consequently, emissions from industrial production emerged as the main source of TEs. The deposition concentrations of Cr, Mn, Ni, Cu, and Pb followed a similar trend to the emissions. However, Cd and As exhibited lower emissions and a less pronounced response relationship. Moreover, Zn concentrations fluctuated within a narrow range and showed a weaker response to emissions. The consistent changes in emissions and TEs deposition concentrations signify a shift in deposition pollution in Lanzhou city from Coal–fired pollution to that driven by transportation and industrial activities. Within this transition, the industrial production process offers significant potential for emission reduction. This insight provides a crucial foundation for managing TEs pollution and implementing strategies to prevent ecological risks.

Regional air quality study by assessing trace metal atmospheric deposition

This study addresses the atmospheric deposition of trace elements investigated in Albania, Croatia and Macedonia in 2010 as part of the European Moss Study. This study provides data on the concentration of ten metals (Cd, Cr, Cu, Ni, Pb, V, Zn, Fe, Al, and Li) in naturally growing mosses. In general, all concentration data follow a lognormal distribution. Cd, Cr, Ni, and Zn show strong fluctuations in the moss samples from Albania and Macedonia, and Pb, Fe, and Al in the mosses from Croatia. The concentrations of Cd, Cu, and Zn were higher in the samples from Croatia than in those from Albania and Macedonia; the concentrations of Cr, Ni, V, Fe, Al, and Li were higher in the samples from Albania than in those from Croatia and Macedonia; and a higher concentration of Pb was found in the samples from Macedonia. The observed relationship between the concentration of lithogenic elements (Al, Fe, and V) and the air quality index (AQI) confirms that moss species have a high capacity to retain atmospheric deposition particles. The anthropogenic emission sources of these elements from local and long-range transport were considered to be the most important factors affecting air quality in the studied areas.

Study on moss biomonitoring of atmospheric deposition of minor and trace elements in the region of Polog, North Macedonia

AbstractA study was conducted to investigate air deposition and to explore the natural or anthropogenic sources of contamination with potentially toxic elements (PTEs) in the region of Polog, North Macedonia, using moss samples as biomonitors of air pollution. The distribution of 22 elements was detected in 43 moss samples collected in the region. Multivariate statistical analysis was applied to the available data. Factor analysis identified five association factors, of which four factors, F1 (Cr, Li, V, Co, Fe, Al, Ni, and As), F2 (K, P, and Mg), F4 (Ag and Cu), and F5 (Ba, Sr, and Mn) were related to lithogenic sources and one factor F3 (Hg, Pb, Cd, and Zn) was related to mixed lithogenic and anthropogenic sources. The content of the elements of F1 is higher in the areas on Mount Šar (area without industrial and urban activities), where Precambrian and Paleozoic shales and Paleozoic sandstones predominate, indicating that their origin is mainly a natural phenomenon. The high contents of the elements from F2, F4, and F5 are also related to the lithology of the studied region. Thus, the high contents of elements from F2 are distributed in the western part of the area, where Precambrian and Paleozoic shists and Paleozoic sandstones dominate, and their contents correlate well with the contents of lithogenic elements in the soil samples from the same region. Elements of Factor 4 have higher contents in the southern part of the region, in areas with Paleozoic‐Mesozoic carbonates and Precambrian‐Paleozoic shales, while elements of Factor 5 occur in the regions with shales, Quaternary sedimentary rocks, and Precambrian‐Paleozoic shales, also indicating the lithogenic character of this factor. In addition to the lithogenic origin of the distribution of elements contained in F3 (Hg, Pb, Cd, and Zn), anthropogenic activities also have an influence on the increased content in the northeastern part of the region. This is due to dust emissions from the Silmak ferrosilicon smelter, as well as emissions from industry (steel smelters) and urban activities of the nearby capital Skopje.

Patterns of trace element deposition in beluga whale teeth reflect early life history

Determination of trace element concentrations in continuously growing biological structures such as otoliths, whiskers, and teeth can provide important insight into physiological and ontogenetic processes. We examined concentrations of 11 trace elements (Li, Mg, Mn, Cu, Zn, Se, Rb, Sr, Cs, Ba, Pb) in the annual dentine growth layer groups (GLGs) of teeth of 66 Eastern Canadian Arctic belugas (Delphinapterus leucas). Several of these trace elements displayed clear and consistent patterns in early life, though few longer term trends or signals were present in trace element data for either females or males. Large changes in Sr and Ba concentrations in fetal dentine reflected in utero shifts in element deposition in the teeth of developing belugas. Marked changes in these elements during the first years after birth were likely associated with the onset of nursing and subsequent weaning. Mg, Mn, and Zn also displayed clear and consistent patterns in early life that correlated strongly with dentine stable nitrogen isotope (δ15N) data, suggesting these elements merit further study as potential tools for studying nursing and weaning. Depositional patterns of Zn and Pb, which have been linked to sexual maturation in female Pacific walruses (Odobenus rosmarus divergens), were inconsistent in beluga teeth. Some individuals (including males) displayed patterns strongly resembling those observed in female walruses, whereas many animals did not, perhaps because they had not yet reached sexual maturity. The lack of clear patterns in trace element deposition after the first few years of life may have resulted from pooling samples from multiple populations/regions collected across more than two decades, but may also indicate that elemental concentrations are primarily driven by other, extrinsic processes later in life, and might be useful as biomonitors of environmental element concentrations or tools for delineating population structure.

Effects of Different Trace Elements and Levels on Nutrients and Energy Utilization, Antioxidant Capacity, and Mineral Deposition of Broiler Chickens

This study investigated the effects of inorganic trace elements (IEs) and sucrose chelated trace elements (SEs) on the growth performance, nutrients and energy utilization, antioxidant capacity, and mineral deposition in broiler chickens, and the efficiency of IEs replaced by SEs at different levels was also evaluated. A total of 448,21-day-old male Arbor Acres broiler chickens with similar body weights were randomly assigned into 6 dietary treatments (8 cages/treatments) in a complete randomized design. Treatments were a basal diet including 2.0 g/kg of IE (IE-2.0) premix, and SE-2.0, SE-1.5, SE-1.0, SE-0.5, and SE-0 were basal diets in which IEs were replaced by SE premix at 2.0, 1.5, 1.0, 0.5, and 0 g/kg, respectively. In general, there was a linear and quadratic decrease in growth performance including average daily feed intake (ADFI) and average daily gain (ADG), apparent and true availability of nutrients (DM, OM, and CP), GE, trace elements (Cu, Zn, Mn, Fe, I, and Se), essential AA (Lys, Met, Arg, His, Phe, Thr, and Val), non-essential AA (Asp, Ser, Glu, Gly, and Cys), superoxide dismutase (SOD), and trace elements (Fe, Zn, Cu, and Mn) in the liver, and an increase in feed-to-gain ratio (F/G) and liver malondialdehyde (MDA), with decreasing SE levels (p &lt; 0.05). In conclusion, under the conditions of this experiment, using half of the sucrose chelated trace elements (Cu, Fe, Zn, and Mn) instead of inorganic trace elements did not affect the growth performance, nutrients and energy utilization, antioxidant capacity, and liver trace element deposition in broiler chickens.

Significant urban hotspots of atmospheric trace element deposition and potential effects on urban soil pollution in China

Rapid urbanization has profoundly altered the spatial patterns of multiple element cycles. Whether and how urbanization shapes the spatial patterns of atmospheric trace element deposition remains, however, poorly understood. Using a newly compiled database on bulk deposition of eight trace elements (i.e., Cu, Ni, Zn, As, Cd, Cr, Hg and Pb) in China, we assessed the urban imprints on the spatial patterns of trace element deposition. Bulk deposition of the eight trace elements all showed a significant increase with closer distance to the nearest large cities, while the urban effect was also mediated by point emission sources and precipitation. We further compiled a database of urban topsoil (0–10 cm) concentrations of the eight trace elements and found that urban soil quality standards were exceeded in 80% of the studied cities for Cr, 49% for As, and less than 25% for other trace elements, respectively. The urban topsoil concentrations of six trace elements (except As and Hg) showed no significant correlations with their background values for natural soils, while we found a significant correlation between bulk deposition and urban topsoil concentrations of trace elements corrected by background values. We also demonstrated that current levels of trace element deposition would substantially increase urban soil pollution over the coming decades. Our findings confirm the occurrence of urban hotspots of trace element deposition and their impact on soil pollution and highlight a need of emission control of trace elements for safety urban soil quality.

Atmospheric Deposition around the Industrial Areas of Milazzo and Priolo Gargallo (Sicily–Italy)—Part B: Trace Elements

The concentrations of trace elements in atmospheric bulk depositions (wet plus dry) were investigated from two highly industrialised areas of Sicily (southern Italy) from June 2018 to July 2019, in order to recognise the main natural and anthropogenic sources. A side objective of this study was to improve the common sampling procedures and analytical methods used for monitoring trace elements in atmospheric deposition. The trace element VWM (Volume-Weighted Mean) concentrations ranged from less than 0.01 μg L−1 for trace elements such as Cs, Tl, and U, up to 24 μg L−1 for minor elements (Al, Zn, Sr), in the filtered aliquot, while they reached concentrations up to 144 μg L−1 for the same elements, in the unfiltered aliquot. Therefore, significant differences in concentrations between these two aliquots were found, particularly for Al, Fe, Ti, Zn, Cr, Pb, Se, Cs, and U. This implies that filtering operations may produce a consistent underestimation of concentrations of certain ‘constituents’ of the atmospheric deposition. Natural (marine spray, local and regional geogenic input, volcanic emanations) and anthropogenic sources (industrial emissions, auto vehicular traffic, and diffuse background pollution) which influence rainwater chemistry were identified. Enrichment factors (EFs), with respect to the upper crust composition, provided clear evidence of the different sources above mentioned: Ti, Fe, Al, Cs, Cr, Rb, and Co have low EFs (&lt;1), and are referable to the (local and/or regional) geogenic input, while Se, Sb, Zn, B, Cd, Cu, Mo, Sr, As, with high EFs (&gt;10), highlight the influence of marine and/or industrial sources. The study produced a novel dataset on the atmospheric deposition rate of several trace elements, which had never been studied in the investigated areas. Finally, a comparison of trace element deposition rates in the studied areas with the atmospheric deposition reported for 53 different sites, belonging to 20 different European nations, was made. The comparison showed that some elements, such as Al, V, Zn, and Mo had higher median deposition fluxes in the Sicilian sites than in European monitoring sites.

Effect of past century mining activities on sediment properties and toxicity to freshwater organisms in northern Sweden

The release of toxic metals from local mining activities often represents a severe environmental hazard for nearby lake ecosystems. Previous studies on the impact of mining have primarily focused on single lakes, with less emphasis on spatial and temporal recovery patterns of multiple lakes within the same catchment, but with different hydrological connection and distance to the pollutant source. This knowledge gap prevents us from assessing the real environmental risk of abandoned mines and understanding ecosystem recovery. This study explores the intensity and spatial patterns of sediment contamination and the potential for ecosystem recovery in three lakes in close vicinity of a lead (Pb) and zinc (Zn) mine in Sweden that has been inoperative for >20 years. Dated (210Pb and 137Cs) sediment cores from each lake were used to reconstruct temporal patterns in trace element deposition and relate those with past mining activities. Results show that all lakes were affected by mining, indicated by increasing Pb and Zn concentrations and decreasing organic matter content, at the onset of mining. However, the extent and timing of mining impact differed between lakes, which was partly ascribed to differences in the historical use of tailings and settling ponds. Assessment of toxicity levels in sediments, based on normalized Probable Effect Concentration Quotient (PEC-Q) to organic matter content, provided more consistent results with the historical mining than conventional methods, showing a decreasing impact in lakes once the operations ceased. Still, sediment Pb concentrations were > 10 times higher than pre-mining values, evidencing the urgent need for remediation actions in the study lakes. This study highlights the importance of considering spatial heterogeneity in metal deposition, sediment organic matter content, and hydrological connectivity with tailings when risk assessments are performed in mining-impacted lakes. The use of normalized PEC-Q in toxic assessments is also recommended.

The Effects of Phytase and Non-Starch Polysaccharide-Hydrolyzing Enzymes on Trace Element Deposition, Intestinal Morphology, and Cecal Microbiota of Growing-Finishing Pigs.

This study investigated the effects of supplementing phytase and non-starch polysaccharide-degrading enzymes (NSPases) to corn-soybean meal-based diet on the growth performance, trace element deposition, and intestinal health of growing-finishing pigs. Fifty pigs were randomly assigned into the control (basal diet), phytase (basal diet + 100 g/t of phytase), β-mannanase (basal diet + 40 g/t of β-mannanase), β-glucanase (basal diet + 100 g/t of β-glucanase), and xylanase (basal diet + 100 g/t of xylanase) groups. The results show that the supplementation of phytase and NSPases had no impacts (p > 0.05) on the growth performance of pigs. Compared with the control group, pigs fed with xylanase had higher (p < 0.05) Zn concentrations in the ileum and muscle and those fed with phytase had higher (p < 0.05) Zn concentrations in the ileum. Phytase and xylanase supplementation decreased (p < 0.05) fecal Zn concentrations in pigs compared with the control group (p < 0.05). In addition, phytase, β-mannanase, β-glucanase, and xylanase supplementation up-regulated (p < 0.05) the FPN1 expression, whereas xylanase up-regulated (p < 0.05) the Znt1 expression in the duodenum of pigs compared with the control group. Moreover, phytase, β-glucanase, and xylanase supplementation up-regulated (p < 0.05) the jejunal Znt1 expression compared with the control group. The intestinal morphology results show that the phytase, β-mannanase, and xylanase groups had increased villus heights (VHs), an increased villus height-crypt depth ratio (VH:CD), and decreased crypt depths (CDs) in the duodenum, whereas phytase, β-mannanase, β-glucanase, and xylanase groups had decreased VH and VH:CD, and increased CD in the jejunum compared with the control group (p < 0.05). Pigs fed with exogenous enzymes had decreased bacterial diversity in the cecum. The dietary supplementation of NSPases increased the relative abundance of Firmicutes and decreased spirochaetes (p < 0.05). Compared with the control group, dietary NSPase treatment decreased (p < 0.05) the opportunistic pathogens, such as Treponema_2 and Eubacterium_ruminantium. Moreover, the relative abundances of Lachnospiraceae_XPB1014 and Lachnospiraceae were enriched in the β-glucanase and β-mannanase groups (p < 0.05), respectively. In conclusion, phytase and xylanase supplementation may promote zinc deposition in pigs. Additionally, the supplementation of NSPases may improve the gut health of pigs by modulating the intestinal morphology and microbiota.