Zn Source Research Articles

Spatial Variability in the Speciation of Lead (Pb) and Other Metals Across Urban Lawns Is Linked to Post-Deposition Weathering Reactions

The historical use of lead (Pb) poses ongoing health risks via exposure to contaminated urban soils. However, there is limited information about heterogeneity in Pb speciation and distribution at the house lot scale. This study determined highly spatially resolved Pb and other metal speciation along horizontal transects and vertical soil cores from three homes in the Akron, Ohio (USA) municipal. Solid phase characterization was coupled with a sequential extraction protocol to determine operationally defined speciation (exchangeable (MEX), reducible (MRED), oxidizable (MOX), and residual (MRES)). Lead and Zn were strongly correlated across all fractions (R2 = 0.92). Total extractable Pb and Zn were found in low weight percent concentrations nearest to the homes, and speciation was dominated by MEX and MRED. High Pb in the MEX fraction was correlated with the presence of Pb-bearing paint chips in the soil. Lead in the MEX fraction in soils near the homes decreased with increasing time due to exterior renovations coupled with increases in Pb and Zn in the MRED fraction. These results suggest that homes are the dominant source of Pb and Zn due to the weathering of exterior surfaces and highlight the acute risk of exposure to more labile Pb immediately following exterior renovations and damage to home exteriors in areas of older housing stock.

Nano-sized ZnO enhances photosynthetic parameters, yield and Zn content in rice (Oryza sativa)

A pot culture experiment was conducted during rainy (kharif) season of 2021 at ICAR-Indian Institute of Rice Research, Hyderabad, Telangana to study the influence of the foliar application of various Zn sources such as nano ZnO, bulk ZnO, and ZnSO4 on rice crop. The experiment was laid out in a completely randomized design (CRD) with the following treatments, containing 3 concentrations of bulk ZnO (500 mg/litre, 1000 mg/litre, and 1500 mg/ litre), 3 concentrations of nano ZnO (50 mg/litre, 100 mg/ litre, and 150 mg/litre), 0.5% ZnSO4 and control with 3 replications. The findings revealed that ZnO nanoparticles (NPs) positively impacted rice grain yield, dry matter accumulation, and Zn content. Compared to the control (no zinc), ZnO NPs (150 mg/litre) and standard ZnSO4 treatments exhibited the highest plant height (83.3 cm and 73.7 cm, respectively), grain yield (5.97 g/pot and 6.03 g/pot), and straw yield (7.82 g/pot and 7.94 g/pot). The increased photosynthetic substances and higher dry matter accumulation throughout the rice growth stage contributed to the enhanced grain yield. Furthermore, supplementing Zn via nano ZnO (150 mg/litre) and 0.5% ZnSO4 resulted in significant Zn enrichment: 33,35; 77,87 and 21, 28% in straw, grain and soil, respectively over control plants. This study effectively demonstrates that ZnO nanoparticles have the potential to serve as high-performance fertilizers, benefiting both rice yield and quality.

Zn Isotope Tracing Unveils Primary Anthropogenic Zn Sources in Glacial Cryoconite of the High Asian Mountains

AbstractZinc (Zn) exerts a significant influence on the global environment, terrestrial ecosystems, and human health. The application of Zn isotopes (δ66Zn) has been suggested as a potent tool for tracing environmental contamination. However, studies focusing on Zn isotope tracing within the cryosphere areas are notably limited. Here we present the first data set on Zn isotopes in glacial cryoconite, based on observations over a large regional scale in High Asian Mountains (including Tibetan Plateau (TP) and its surroundings of western China). The results showed that glacial cryoconite had a general heavy Zn isotopic signature in various TP locations, with δ66Zn values ranging from −0.22‰ to +0.87‰. Employing the MixSIAR model, the overall Zn contribution source to the cryoconite was mineral dust (36%) > coal burning (33%) > non‐exhaust traffic emissions (22%) > industrial smelting (10%). We ascertained that anthropogenic sources account for the primary contribution (about 60%–73%) of Zn inputs in all glacial locations, with coal burning emerging as the foremost anthropogenic contributor (mean 33%). Anthropogenic Zn in various TP locations was primarily derived from Zn emissions resulting from coal combustion, though it is also predominantly influenced by industrial smelting source in cryoconite of the Tianshan Mountains. Our results aligned with coal combustion data from the energy inventory of western China, suggesting that regional coal burning likely represents the foremost source of atmospheric Zn pollutant emission and deposition in the High Asia mountain glaciers.

Pollution Characteristics, Risk Assessment, and Source Analysis of Heavy Metals in Soil from a Typical Abandoned Antimony Smelting Factory

Considering the surface soil （0-20 cm） from a typical abandoned antimony smelting factory area in Dachang Town, Qinglong County, Guizhou Province, as a case study, a total of 14 soil samples were systematically collected from both within and outside the smelting factory area. The analysis focused on the pollution status, distribution characteristics, and potential ecological risks of heavy metals such as Sb, As, Cd, Cr, Pb, Cu, Zn, Ni, and V in the soil. Additionally, an evaluation and analysis of pollution sources were conducted. The results showed that the mean concentrations of heavy metals including ω（Sb）, ω（As）, ω（Cd）, ω（Cr）, ω（Pb）, ω（Cu）, ω（Zn）, ω（Ni）, and ω（V） in the surface soil of the abandoned antimony smelting factory ranged from 4.58 to 15 049.33 mg·kg-1. With the exception of Cr and Ni, all values exceeded the background values of soils in Guizhou province. The single factor pollution indices of Sb and As were 83.61 and 7.01, respectively, indicating severe contamination. In contrast, Pb fell within the non-polluted to slightly polluted range. The comprehensive potential ecological risk of soil heavy metals was characterized by severe potential ecological risk levels for Sb, As, and Cd, while the remaining heavy metals fell within a range of moderate to substantial potential ecological risk levels. The assessment of the geoaccumulation index revealed that the soil in the study area was primarily contaminated by Sb and As, predominantly exhibiting contamination levels ranging from moderate to severe. The results from the RAC method suggested that Sb was the dominant focus for remediation in this abandoned smelting factory. The two primary pollutants, Sb and As, exhibited elevated levels in leachate toxicity, acid-soluble fraction, available fraction, gastric phase, and intestinal phase in terms of bioavailable content, indicating a certain potential hazard. Further, correlation analysis indicated a certain correlation between the total amount of heavy metals and leachate toxicity, available fraction, acid-soluble fraction, reducible fraction, oxidizable fraction, gastric phase extractable fraction, and intestinal phase extractable fraction. The APCS-MLR model indicated that the sources of Sb, As, Zn, Cu, and Cd were primarily industrial, while the sources of Cr and V were mainly natural, and Pb originated mainly from mixed sources.

Assessment of the intake of essential elements by consumption of meat and liver from moose (Alces alces) and wild boar (Sus scrofa) inhabiting the north-west of Russia

This study aimed to analyze the concentrations of the essential elements (Co, Cu, Fe, Mg, Mn, and Zn) in the edible tissues (muscle=meat, liver) of the large game mammals (moose Alces alces L. (n=17) and wild boar Sus scrofa L. (n=46)) and to assess the nutritional values of these food products through the fulfillment of Dietary Reference Values (DRVs) for the aforementioned elements. The values of most of the elements measured in the animals' tissues were either comparable to or greater than those observed in domestic animals and the same species from other countries. No significant species-dependent differences were observed in the meat for the studied elements, but the concentrations of Co, Cu, and Mn were higher, and the levels of Fe and Zn were lower in the moose liver compared to the wild boar liver. According to DRVs for adults, the game meat and liver are poor sources of Co, Cu (except liver), Mg, and Mn. However, the consumption of liver from studied species meets the adult requirements for Cu (moose) and Fe (moose and wild boar). Both the meat and liver of game animals may be considered as good sources of Zn.

Distribution patterns, health hazards, and multivariate assessment of contamination sources of As, Pb, Ni, Zn, and Fe in agricultural soils

Soil heavy metal contamination is a worldwide environmental concern that presents considerable risks to ecosystems, agricultural progress, and human health. This study aims to evaluate the potential environmental and health hazards linked to the presence of arsenic (As), lead (Pb), nickel (Ni), zinc (Zn), and iron (Fe) in agricultural soil in Al Majma’ah governorate, Saudi Arabia. The contamination factor (CF), pollutant load index (PLI), chronic daily intake (CDI), hazard index (HI), and total lifetime cancer risk (LCR) were calculated for 34 soil samples. The results from the CF and PLI analysis demonstrate that the examined soil has a low contamination factor and is free from heavy metal pollution. The average CDI values for adults and children exhibited the following descending order: Fe > Zn > Cu > Pb > As. The highest HI values observed in adults ranged from 0.0375 (Fe) to 0.00019 (Zn), but in children, the range was from 0.3497 (Fe) to 0.0018 (Zn). The hazard index values for heavy metal(loid)s (HMs) in the Al Majma’ah area were all below 1.0, suggesting that residents in the area are not exposed to a significant non-carcinogenic risk. The LCR values ranged from 8.37E−06 to 7.80E-05 for As in both adults and children, and from 7.50E−08 to 6.98E-07 for Pb. The findings indicated a level of risk that was deemed acceptable or tolerable, without any significant adverse health effects

Trace and Minor Element Analysis of Azurite Blues in Fine Arts: Possibilities and Limitations in Provenance Studies.

Azurite, a historical blue mineral pigment, has previously been described to contain certain elemental impurities. These may originate from host rocks, vein fillings, or the primary copper ore mineralization. In this study, azurites (and also green malachites) from three important Central European deposits with a potential of being exploited for pigment usage already in the Middle Ages have been studied, together with azurite from Chessy, France, with a different geological setting. Using electron probe microanalysis and, more importantly, laser ablation inductively coupled plasma mass spectroscopy for trace elemental analysis, several indicators were pinpointed as important for provenance: characteristic elemental fingerprint of the deposit, e.g., elevated lead (Pb) in combination with rare earth elements, may be combined with zinc (Zn)/arsenic (As) ratio (indicating sources of excess Zn in the primary deposit) and the overall amount of metal impurities (suggesting the source mineral of copper for azurite formation). In addition, malachites from the same deposits were found to preferentially incorporate primary ore metal elements as well as Cd, Mg, Mn, or U. Therefore, if azurite pigment contains an elevated amount of malachite as an impurity, it may significantly influence the overall elemental composition. The results obtained on geological samples were applied to two micro-samples of works of art containing azurite-rich layers originating from the 13th-14th and 16th centuries. It was shown that it is highly beneficial to focus on the overall trace elemental composition of the paint layer and not on the admixed mineral grains, as their presence, especially in minute micro-samples, is largely accidental and thus not representative. Although a higher number of samples need to be studied in the future, the newly described criteria made it possible to exclude some of the localities of the employed azurite pigment. This confirmed the key importance of trace elements analysis of mineral pigments for the provenance studies of fine arts.

Effects of dietary calcium and microbial phytase on the bioavailability of two sources of zinc in broilers

ABSTRACT 1. The objective of this study was to test the effect of microbial phytase and calcium (Ca) levels on the Zn bioavailability depending on the Zn source. 2. A total of 144, one-day-old broilers received a diet containing 40 mg Zn/kg for 1 week. They were then assigned to one of the eight experimental treatments during 2 weeks. Diets contained 27 mg native Zn and were formulated according to a 2 × 2 × 2 factorial design with two added Zn sources (23 mg Zn/kg), sulphate (ZnSO4) or oxide (ZnO); two dietary Ca levels of either 6 (low) or 10 g/kg (moderate); and two microbial phytase levels, of either 0 or 750 phytase unit/kg. 3. Moderate Ca plus phytase improved body weight gain (BWG) and low Ca level without microbial phytase decreased tibia weight (Ca × Phy; p = 0.049). Zinc oxide resulted in a higher tibia development (i.e. tibia weight and length; p < 0.05) and BWG (p = 0.009) and lower FCR (p < 0.001) compared to ZnSO4. 4. Phytase improved tibia Zn concentration especially in birds given ZnSO4 compared to ZnO (Zn × Phy; p = 0.049). Moderate Ca diets improved tibial characteristics and Zn deposition compared to low Ca diets (p < 0.05). 5. Soluble Zn in the gizzard increased in the presence of phytase (p = 0.011), while higher dietary Ca reduced this in birds receiving ZnO (p = 0.004). In the jejunum, Zn solubility was higher with phytase (p = 0.008). 6. Under the conditions of this study, dietary levels of Ca and microbial phytase affect Zn availability in broilers more than the Zn source.

A framework integrating affinity propagation algorithm and spatial bivariate analysis for enhanced identification and localisation of soil heavy metals pollution sources.

The accurate identification of pollutant sources and their spatial distribution is crucial for mitigating soil heavy metals (SHMs) pollution. However, the receptor model struggles to effectively categorize pollutant sources and pinpoint their locations and dispersion trends. We propose a novel comprehensive framework that combines a receptor model, random forest (RF), affinity propagation (AP) algorithm, and bivariate local indicator of spatial association (BLISA), to optimize the traditional approach for tracing SHMs sources in industrial regions. We apportioned SHMs sources using a receptor model combined with RF, while BLISA combined with AP methods were employed to accurately locate the source areas and identify their dispersion tendencies. The results revealed that SHMs originated from mixed sources of equipment manufacturing agglomeration and agricultural activities (59.0%), geological background (30.5%), and emissions from heavily-polluting industries (10.5%). The pollution sources of soil Cd and Pb were located near specific industries, showing characteristics of multi-site concurrent pollution diffusion influenced by their proximity to industrial sites. The spatial distribution of Cr, Cu, and Zn sources was concentrated in high-density urban industrial areas, transitioning from point to nonpoint sources, with diffusion patterns influenced by the spatial agglomeration effect of industries. Our enhanced framework accurately identifies the location of SHMs sources and their dispersion tendencies, thereby improving regional soil pollution management.

Enhancing the nutritional values of egg yolks of laying hens by different dietary sources of omega-3 fatty acids, vitamin e and trace elements

The present study aims to investigate the effect of whole flaxseed (WFS), fish oil (FO), and different sources of Se, Zn, and Fe on lipid metabolites, antioxidant status, immunity, egg yolks’ minerals (Se, Zn and Fe) and fatty acids and eggs’ lipid and health index in laying hens. A total of 144 hens were divided into 6 groups with 6 replicated of 4 hens each. The laying hens were fed diets containing 0, 7.5 % whole flaxseed (WFS)+1.5 % fish oil (FO), 7.5 %WFS+1.5 % FO+175 mg kg-1 vitamin E (VE), 7.5 %WFS+1.5 % FO+ 175 mg kg-1 VE +inorganic sources of Se, Zn, and Fe (ISeZnFe), 7.5 %WFS+1.5 % FO+175 mg kg-1 VE+ organic sources of Se, Zn, and Fe (OSeZnFe) and 7.5 %WFS+1.5 % FO+ 175 mg kg-1 VE +nano-source of Se, Zn, and Fe (NSeZnFe) from 40 to 50 weeks of age. Results clarified that incorporation of 7.5 %WFS+1.5 %FO+VE+OSeZnFe or 7.5 %WFS+1.5 %FO+VE+NSeZnFe increased serum concentration of HDL-cholesterol and HDL/LDL ratio, while reduced LDL-cholesterol and the hypercholesteremia index (RHCH) in comparison with control. Dietary 7.5 %WFS+1.5 %FO+VE+OSeZnFe or 7.5 %WFS+1.5 %FO+VE+NSeZnFe increased concentrations of total antioxidants capacity and vitamin E and reduced concentrations of malonaldehyde (MDA) in blood serum and egg contents. Interestingly, dietary inclusion of 7.5 %WFS+1.5 %FO+VE+OSeZnFe, or 7.5 %WFS+1.5 %FO+VE+NSeZnFe increased α-linolenic acid (ALA), eicosapentaenoic acid (EPA), docosapentaenoic acid (DPA), docosahexaenoic acid (DHA), and total n-3 PUFAs concentrations in egg yolk, while reduced arachidonic acid (ARA) in the egg yolks, whereas n-6/n-3 PUFAs ratio was decreased significantly. Moreover, incorporation of 7.5 %WFS+1.5 %FO+VE+OSeZnFe, or 7.5 %WFS+1.5 %FO+VE+NSeZnFe improved egg health indices. It might be concluded that, inclusion of 7.5 %WFS+1.5 %FO+VE+OSeZnFe, or 7.5 %WFS+1.5 %FO+VE+NSeZnFe in hens’ diets had a positive effect on antioxidative properties in blood serum and eggs yolks contents; at the same time, it improved the egg yolk lipids, fatty acids and its related health and nutritional indices.

The concentrations of microelements in forest mushrooms are influenced by soil pH and C/N ratio and less by stand characteristics

The fruitbodies or sporocarps formed by mushrooms can accumulate mineral elements, such as selenium, zinc or copper, making them an important source of micronutrients essential to humans. However, the literature about environmental factors affecting mineral composition in mushrooms is scarce and limited to the ambiguous impact of soil properties and region. In our study, we investigated the effects of tree stand characteristics (tree species and tree canopy cover), understory cover, and soil properties (pH and C/N ratio of the soil) on the concentration of minerals in six edible mushroom species: Laccaria laccata, L. proxima, L. amethystina, Lepista nuda, Lycoperdon perlatum, and Calvatia excipuliformis, collected on 20 plots covered by stands of different tree species composition and varying in the understory cover. We estimated the concentration of eight elements (Zn, Se, Mg, Mn, Cu, Co, Cr, Mo) using the ICP-MS (Inductively Coupled Plasma - Mass Spectrometry) technique and compared their concentration between the plots, using ordination and linear regression methods. Our research revealed that mushroom species identity, including its ecological role and phylogenetic affinity, had the greatest effect on the mineral composition of mushrooms. The effect of environmental factors depended also on the micronutrient identity. Some elements were not affected at all (Co, Cr), some only by soil reaction or C/N ratio (Mn, Mg, Cu), while others were influenced by both tree stand characteristics and soil properties (Se, Zn, Mo). This knowledge enables us to maximize the content of minerals in harvested mushrooms by collecting them in specific areas. For example, mushrooms, which are sources of Se and Zn, can be gathered in coniferous forests characterized by acid soils, low canopy cover, and minimal understory cover. This targeted collection approach can effectively increase the mineral content in harvested mushrooms, thereby enhancing their health benefits.

18 Impacts of supplementing sulfate vs. hydroxychloride sources of Cu, Mn, and Zn on heifer growth performance and physiology during feed restriction and high-starch challenge periods

Abstract This study evaluated the effects of supplementing different sources (sulfate vs. hydroxychloride) of Cu, Mn, and Zn during feed restriction and high-starch challenge periods on heifer growth performance and physiology. On d 0, Nelore heifers (n = 40) were stratified by body weight (BW = 238 ± 38 kg) and age (21 ± 1 mo), and individually allocated into 1 of 40 drylot pens. The study was divided: washout (d 0 to 27), nutrient surplus (d 28 to 55), nutrient restriction (d 56 to 83), and high-starch challenge (d 84 to 112). The washout period consisted of limit-feeding Tifton hay (2.5% of BW; DM basis) and providing free choice access to white salt only. On d 28, heifers were randomly assigned to receive protein DM supplementation (0.10 to 0.20% of BW) added with sulfate (SUL) or hydroxychloride (HYD) sources of Cu, Mn, and Zn (≥ 260, 200, and 960 mg of Cu, Mn, and Zn per kg of supplement DM) from d 28 to 112 (n = 20 heifers/treatment). From d 28 to 55, heifers were offered ad libitum Tifton hay. From d 56 to 83, heifers were limit-fed 50% of average hay DM intake consumed in the last 6 d of the previous phase (d 50 to 55). From d 84 to 112, each respective protein supplement was mixed with a starch-based total mixed ration (TMR). Heifers were gradually adapted to the starch-based TMR by increasing the concentrate DM amount while simultaneously decreasing the hay DM amount by 20% every 7 d (starting with 35% concentrate and 65% hay on d 84 and ending with 80% concentrate and 20% hay from day 106 to 112). Individual heifer shrunk BW were collected on d 0, 28, 56, 84, and 112, following 12 h of feed and water withdrawal. Effects of treatment × day and treatment were not detected (P ≥ 0.37) for heifer BW, average daily gain (ADG), and dry matter (DM) intake, except for ADG from d 28 to 56, which was less (P = 0.05) for SUL vs. HYD heifers (-0.21 ± 0.05 vs. -0.10 ± 0.05 kg/day, respectively). Effects of day, but not treatment × day and treatment (P ≥ 0.43), were detected for fecal pH, which remained relatively constant from d 0 to 84, and then decreased (P &amp;lt; 0.01) from 7.2 on d 84 to 5.8-6.0 on d 110. Overall, protein supplementation added with hydroxychloride sources of Cu, Mn, and Zn had minor positive effects on heifer growth performance immediately following a washout period, but did not improve heifer growth performance and fecal pH during nutrient restriction and high-starch challenge periods, compared with protein supplementation added with sulfate sources of same metals.

391 The impact of trace mineral source on systemic immunological status associated with early embryonic loss in lactating dairy cattle

Abstract Milk production has doubled from 1970 to 2009 but has been associated with a decline in fertility. Around 25% of failed pregnancies in dairy cattle are due to embryonic loss. Mineral bioavailability may affect embryonic retention, so we hypothesized that Zn, Cu, and Mn sources will influence systemic immunological status, which affects early embryonic retention. Holstein cows (n = 58) were randomly assigned to one of two daily oral drench trace mineral (Zn, Cu, and Mn) treatments 30 d before breeding (d -30): 1) Inorganic (ITM) or 2) Metal Methionine Hydroxy Analog Chelate (MMHAC). Before treatments began, cows were assigned to a semen type, beef vs. Holstein, equally, across treatments. All cows underwent a double Ovsynch protocol and were artificially inseminated on d 0. Humoral immunological status was assessed in serum samples taken on d 0 and d 7. Immune activity was quantified via a D2Dx systemic immunity score, which assesses samples for the presence of IgG, IgM, cytokines, and complement proteins. Ultrasonography was utilized for pregnancy confirmation on d 35, classifying cows as pregnant (P) or open. Progesterone analysis from d 21 plasma was used to categorize open cows as either non-pregnant (NP) or early embryonic loss (EEL). Statistical analyses in R Studio were completed, in two models based on pregnancy (P vs EEL and NP vs EEL), to determine the effects of mineral treatment, pregnancy status, semen type, and all interactions on humoral immune status. In the P vs EEL model, there were no effects (P &amp;gt; 0.30) of semen type, mineral treatment, pregnancy status, or any interactions on systemic immunity score on the day of breeding (d 0) or d 7. On d 0, cows provided MMHAC had a systemic immunity score of 0.073 ± 0.008 but were not different (P &amp;gt; 0.34) from ITM cows (0.063 ± 0.006). This trend continued on d 7 with systemic immunity scores of MMHAC cows not differing (P &amp;gt; 0.32) from ITM cows (0.055 ± 0.004 and 0.061 ± 0.003; respectively). There was a tendency (P = 0.10) for the three-way interaction of semen type x pregnancy x treatment to influence the immunity score change from d 0 to d 7. Pregnant cows on ITM treatment bred with beef semen had a positive change in immunity score (0.020 ± 0.0085). Whereas ITM cows bred with Holstein semen that underwent EEL had a negative change (-0.015 ± 0.0085); all other means were intermediate. In the NP vs EEL model, there were no effects (P &amp;gt; 0.14) of semen type, treatment, pregnancy status, or any interactions on systemic immunity score on d 0, d 7, or the change between d 0 and d 7. In summary, trace mineral bioavailability tended to affect systemic immunological status in P vs EEL cows but not in NP vs EEL cows, which may allow for the elucidation of immunological status differences during pregnancy establishment.

Content, Sources, and Ecological Risk Assessment of Heavy Metals in Soil of Typical Karst County

Soil heavy metals in karst areas have obvious high background value characteristics. Conducting county-level soil heavy metal ecological risk assessment and identifying heavy metal sources in karst areas are of great significance for soil pollution control and land resource management. Taking Pingguo City, a typical karst county in Guangxi Province, as the study object, 3 151 surface and deep soil samples were collected using the grid method and combined to form 785 analytical samples. The contents of eight heavy metal elements, including As, Cd, Cr, Cu, Hg, Ni, Pb, and Zn, were determined. The content characteristics and sources of heavy metals were analyzed using statistical analysis, interpolation analysis, factor analysis, and the absolute principal component-multiple linear regression model （APCS-MLR）. Using the content of heavy metal elements in deep soil （150-200 cm） as background values, the ecological risk assessment of heavy metals in surface soil （0-20 cm） in the study area was conducted using the geo-accumulation index （Igeo） and potential ecological risk index （RI） methods. The results showed that the average content of heavy metal elements in the deep soil of the study area was significantly higher than the background value of the C layer soil in Guangxi Province, and the average content of heavy metal elements in the surface soil was significantly higher than the background value of the A layer soil in Guangxi Province. The spatial distribution of soil heavy metal element content generally showed the characteristics of high in karst areas and low in non-karst areas. The main sources of As, Cr, Ni, Pb, and Zn were soil parent materials, with contribution rates of 74.36%, 84.59%, 93.69%, 79.67%, and 78.17%, respectively. The main sources of Cd were soil parent material sources and unknown sources, with contribution rates of 37.33% and 31.05%, respectively. The main sources of Cu were soil parent materials and unknown sources, with contribution rates of 59.07% and 40.23%, respectively. The main sources of Hg were tectonic activity and mineralization, as well as unknown sources, with contribution rates of 52.49% and 30.65%, respectively. The geo-accumulation index （Igeo） showed that the surface soil was mainly polluted by Cd, with mild or above pollution accounting for 47.78%. The potential ecological risk index （RI） showed that the proportion of surface soil heavy metal comprehensive potential ecological hazards with mild, moderate, strong, and very strong levels was 80.78%, 14.97%, 2.51%, and 1.64%, respectively.

Source-dependent effects of early-life zinc supplementation in milk on growth performance and starter intake of pre-weaned dairy calves

This study aimed to evaluate the effects of milk supplementation with different zinc (Zn) sources on growth rate, starter intake, diarrhea incidence, and nutrient digestibility in dairy calves during the pre-weaning period. Forty newborn Holstein heifer calves were assigned to four treatments: control (no Zn supplementation; CON) or supplementation with 80 mg/day Zn from zinc sulfate (Zn-Sul), chelated zinc (Zn-Bon), or zinc methionine (Zn-Met). The Zn supplements were provided via milk from days 3 to 14 of age. Body weight (BW) and starter intake (SI) were monitored until weaning on day 70. Serum metabolite concentrations were determined in blood samples collected on days 15 and 70. Fecal consistency index (FCI) and frequency of medical treatments were measured during the first 21 days of life. Apparent total tract digestibility (ATTD) was determined in the 10th week of life. Although the effects of Zn supplementation on BW gain or body measurements were non-significant, a tendency for treatment × time interaction on BW was observed, with variations among the experimental groups becoming more pronounced on days 56 and 70, showing higher values in Zn-supplemented calves compared to CON. SI was improved by Zn supplementation, with the greatest response in the Zn-Bon group. Compared to control, ATTD of organic matter, neutral detergent fiber, and starch tended to increase with Zn supplementation. Blood metabolites and FCI did not differ among the experimental treatments. Although no significant difference was detected between Zn-Met and CON, the frequency of medical treatment was significantly lower in Zn-Bon and Zn-Sul compared to CON calves. In conclusion, zinc supplementation in milk, particularly with the organic chelated zinc source (Zn-Bon), showed promising effects on increasing starter intake and reducing medical treatments, along with trends toward enhanced growth and nutrient digestibility in pre-weaned calves.

Dietary Zn proteinate with moderate chelation strength alleviates heat stress-induced intestinal barrier function damage by promoting expression of tight junction proteins via the A20/NF-κB p65/MMP-2 pathway in the jejunum of broilers

BackgroundThe aim of this study was to determine whether and how Zn proteinate with moderate chelation strength (Zn-Prot M) can alleviate heat stress (HS)-induced intestinal barrier function damage of broilers. A completely randomized design was used for comparatively testing the effects of Zn proteinate on HS and non-HS broilers. Under high temperature (HT), a 1 (Control, HT-CON) + 2 (Zn source) × 2 (added Zn level) factorial arrangement of treatments was used. The 2 added Zn sources were Zn-Prot M and Zn sulfate (ZnS), and the 2 added Zn levels were 30 and 60 mg/kg. Under normal temperature (NT), a CON group (NT-CON) and pair-fed group (NT-PF) were included.ResultsThe results showed that HS significantly reduced mRNA and protein expression levels of claudin-1, occludin, junctional adhesion molecule-A (JAMA), zonula occludens-1 (ZO-1) and zinc finger protein A20 (A20) in the jejunum, and HS also remarkably increased serum fluorescein isothiocyanate dextran (FITC-D), endotoxin and interleukin (IL)-1β contents, serum diamine oxidase (DAO) and matrix metalloproteinase (MMP)-2 activities, nuclear factor kappa-B (NF-κB) p65 mRNA expression level, and protein expression levels of NF-κB p65 and MMP-2 in the jejunum. However, dietary supplementation with Zn, especially organic Zn as Zn-Prot M at 60 mg/kg, significantly decreased serum FITC-D, endotoxin and IL-1β contents, serum DAO and MMP-2 activities, NF-κB p65 mRNA expression level, and protein expression levels of NF-κB p65 and MMP-2 in the jejunum of HS broilers, and notably promoted mRNA and protein expression levels of claudin-1, ZO-1 and A20.ConclusionsOur results suggest that dietary Zn, especially 60 mg Zn/kg as Zn-Prot M, can alleviate HS-induced intestinal barrier function damage by promoting the expression of TJ proteins possibly via induction of A20-mediated suppression of the NF-κB p65/MMP-2 pathway in the jejunum of HS broilers.

Organic Zn and nano-Zn amino acids chelates modulate quality growth attributes and antioxidants activity for biofortified apple (Malus x domestica Borkh.) production

Zinc biofortification increase nutritional content of crops to combat Zn deficiency in human diets. Foliar Zn bio-organics can significantly improve Zn content of fruit crops. This method is efficient, can be tailored to specific crop needs, and is crucial for enhancing the nutritional quality of food crops, contributing to better human health outcomes. In order to evaluate the efficacy of foliar sprays in promoting plant growth and development, the study evaluated the comparative efficacy of zinc amino acid complexes with zinc sulphate in apple (Malus × domestica Borkh.) cv. Gala Schniga Schnico during the years 2022 and 2023. Different Zn nutrient sources namely, Zn glycinate (Zn-Gly), Zn gluconate (Zn-Glu), Zn amino acid chelate (Zn-AAC), nano Zn amino acid chelate (NZn-AAC) were applied at the rate of 200 and 400 mg/L each and conventional ZnSO4 at 1250 mg/L with three replicates. Foliar application of the Zn nutrient sources was executed at four stages i.e., 15 days before petal fall, petal fall, 15 days after petal fall, and after harvest. The results revealed that NZn-AAC at 400 mg kg-1 registered the maximum increase in vegetative growth and flowering traits. The superior treatment also exhibited highest fruit set (62.90 %) and fruit yield (5.62 kg/tree) in apple. Fruit quality parameters, in terms of TSS, total sugars, ascorbic acid and anthocyanin contents were increased by 22.9, 17.8, 50.2, and 16.6 per cent, respectively through superior treatment. Fruit flesh and peel nutrient content in terms of P, K, Ca, Mg and Zn also showed improvement through NZn-AAC400 compared to control. Maximum decrease in phytic acid (1.09 %) and increase in ursolic acid (273.95 µg/mL) were also reported with NZn-AAC400. The differences between Zn nutrient sources were analysed using PCA, which explained 95.70 per cent (PC1), 97.81 per cent (PC2), 99.11 per cent (PC3), 99.42 per cent (PC4) and 99.63 per cent (PC5) of the cumulative variance based on Eigen value (>1). In accordance with the results, Zn amino acid complexes emerged as beneficial environment-friendly Zn source for improving growth, fruit yield, quality with higher Zn bio-availability compared to ZnSO4.

Determination of optimal dietary calcium levels under different sources of zinc in Jing tint 6 layer chicks from 15 to 42 d of age

An experiment was conducted to investigate the optimal dietary calcium (Ca) levels in Jing Tint 6 layer chicks fed different sources of zinc (Zn). The diets were formulated using 2 different Zn sources: organic Zn (80 mg/kg Zn as HMZn) and inorganic Zn (80 mg/kg Zn as sulfate). For each Zn source, 5 diets were formulated to contain Ca levels of 0.80, 0.90, 1.03, 1.10, and 1.20%. Results showed that dietary Ca levels had a significant effect on body weight gain (BWG) and feed conversion ratio (FCR) (P < 0.05). In addition, BWG was significantly enhanced by the organic Zn diets (P < 0.05). Dietary Ca levels significantly affected tibia length (P < 0.05) and serum Ca and P contents (P < 0.05) but did not affect serum total protein (TP), albumin (ALB), or alkaline phosphatase (ALP) levels (P > 0.05). The apparent total tract retention coefficients (ATTRC) of Ca showed a quadratic trend (P < 0.05) with increasing Ca levels. Furthermore, organic Zn diets reduced excreta Ca output and enhanced the ATTRC of Ca in birds on d 42 compared with inorganic Zn diets. The optimal dietary Ca levels were estimated as 0.93, 0.94, and 0.96% for birds fed organic diets and 1.07, 0.99 and 0.94% for birds fed inorganic diets using nonlinear models based on the criteria of BWG, tibial length, and serum P, respectively. In general, organic Zn supplementation improved growth performance and reduced the calcium requirements of birds on d 42.

Identification of Anthropogenic and Natural Inputs of Sulfate into River System of Carbonate Zn-Pb Mining Area in Southwest China: Evidence from Hydrochemical Composition, δ34SSO4 and δ18OSO4

The release of pollutants from lead-zinc mining areas poses a significant threat to the environment, making pollution tracing crucial for environmental protection. However, the complexity of carbonate mining areas makes tracing these pollutants challenging. This study used δ34SSO4 and δ18OSO4 isotopes combined with the Stable Isotope Mixing Models in R (SIMMR) to assess anthropogenic sulfate sources in the Daliangzi mining area. The river water types were mainly Ca2+-Mg2+-HCO3−, and SO42−, which are significantly influenced by dolomite dissolution. The δ34SSO4 values ranged from 6.47‰ to 17.96‰ and the δ18OSO4 values ranged from −5.66‰ to 13.98‰. The SIMMR results showed that evaporite dissolution in tributaries, driven by gypsum, contributed 31% of sulfate, while sulfide oxidation, sewage, and atmospheric deposition contributed 19%, 18%, and 24%, respectively. The tailings pond near Xincha Creek has a higher sulfate release potential than the processing plant near Cha Creek. In the mainstream, sulfide oxidation contributed 25%, primarily from mine drainage. Anthropogenic sources, including sulfide oxidation, fertilizers, and sewage, made up about 50% of the total sulfate, with sulfide oxidation accounting for half of this input. The strong correlation between the Zn and SO42− concentrations (R2 = 0.82) and between the Zn and the contribution from the sulfide oxidation (R2 = 0.67) indicates their co-release during sulfide oxidation, making SO42− a proxy for tracing Zn sources. This study highlights the utility of δ34SSO4 and δ18OSO4 with SIMMR in tracing anthropogenic inputs and underscores the significant impact of mining on river systems and the sulfur cycle.

Trace Element Analysis of Algerian Cuisine: Insights from Iron, Zinc, Cobalt, Chromium, and Rubidium Content Using Instrumental Neutron Activation Analysis Method

This work aims to assess for the first time in Algeria the concentration of five essential nutrient elements', namely: chromium (Cr), cobalt (Co), iron (Fe), rabidium (Rb), and zinc (Zn), in a dozen commonly consumed Algerian food items chosen and ordered according to their Algerian cuisine availability: bread, flour, spaghetti, bean, lentils, tomatoes, zucchini, eggs, beef, Sardina pilchardus (sardine), Merlangius merlangus Linnaeus, 1758 (whiting), and Mullus barbatus (red mullet) fish. Instrumental neutron activation analysis (INAA) was used for this study due to its ability and high sensitivity to detect trace-level concentrations. Among these items, results showed that beef exhibits notably elevated levels of Cr (4.02 mg/kg) and Rb (9.41 mg/kg), whereas M. barbatus fish emerges as a significant source of Zn (268 mg/kg). Lentils have substantial Fe content (151 mg/kg), emphasizing their nutritional significance. Additionally, zucchini demonstrates considerable levels of both Cr (2.17 mg/kg) and Rb (6.38 mg/kg). These findings underscore the diverse elemental profiles of staple Algerian cuisine foods, delineating their potential dietary contributions and highlighting essential sources of these micronutrients.