Zinc Residues Research Articles

Application of Oxygen-enriched Side-blowing Technology in Treating Zinc Leaching Residue in China

Zinc hydrometallurgy is the main process of zinc smelting in the world. The leaching residue produced by different hydrometallurgical processes have different components, but they contain valuable metals such as zinc, silver, gold, indium and germanium, and heavy metals such as lead, cadmium and arsenic. In China, leaching residue is defined as hazardous waste, which requires harmless treatment and recovery of valuable metals. At present, China’s main zinc leaching residue treatment technologies include Welz kiln, fuming furnace and Top-submerged lance Smelting furnace. These technologies have been applied for many years and are mature and reliable, but they need further improvement in energy conservation and environmental protection. In recent years, with the continuous progress of China’s smelting technology, the oxygen-enriched side-blowing technology has been successfully applied to the treatment of zinc leaching residue, mainly including the Side-submerged combustion smelting technology of China ENFI and the Vanukov side-blowing technology. At present, the above two side blowing technologies have been put into industrial practice in many zinc smelters in China, which are characterized by low energy consumption, high recovery rate of valuable metals and high sulfur recovery rate. This paper introduces the application of the above two side blowing technologies in China’s zinc smelters, and compares them from furnace structure, production operation, and technical indicators. Oxygen-enriched side-blowing technology will become the mainstream treatment process of zinc residue in China and even in the world in the future.

Ameliorative effects of Dunaliella salina microalgae on nanoparticle (ZnO NPs)-induced toxicity in fish.

Dunaliella salina (D. salina) is a well-known microalga that contains considerable amounts of nutritious and medicinal bioactive components. This work studied the modulatory role of D. salina against zinc oxide nanoparticle (ZnO NPs)-induced neurotoxic effects in adult zebrafish. Fishes were subjected to 0.69mg L-1 (1/5th 96-h LC50) for 4weeks; then, fishes were supplemented with D. salina in the diet for 2weeks at two levels (15 and 30%). Exposure to ZnO NPs induced a significant increase in the levels of reactive oxygen species (ROS), hydrogen peroxide (H2O2), malondialdehyde (MDA), and 8-hydroxy-2-deoxyguanosine (8-OH-dG) while accompanied with downregulation of antioxidant genes in the brain of exposed fishes. Brain neurochemistry and enzyme activities were also altered following ZnO NP exposure. ZnO NPs significantly reduced the neurotransmitters and acetylcholinesterase (AchE) activity while increasing Alzheimer's disease-related proteins and inflammatory response via upregulation of tumor necrosis factor (TNF-α). Additionally, ZnO NPs increased the indices of brain's DNA oxidative damage, increasing brain tissue's metallothionein (MT) and zinc residues. ZnO NPs upregulated the transcription patterns of apoptosis-related genes (casp3 and p53). D. salina dietary co-supplementation with ZnO NPs alleviated the ZnO NPsZnO NP-induced neuro-oxidative damages by lowering the lipid, DNA damage, and inflammatory biomarkers. Besides, D. salina alleviating responses were linked with increasing the levels of the assessed antioxidants. Conclusively, D. salina dietary supplementation induced potential alleviating effects of the ZnO NP-induced neurotoxicity in adult zebrafish.

Copper And Zinc Mining Tailings as A Partial Replacement for Cement to Increase the Compressive Strength of Concrete

This study uses copper and zinc mining waste from mining activity as a partial substitute for cement in the concrete mix. This initiative seeks to strengthen the compressive strength of concrete. Copper and zinc waste can partially replace the cement content in concrete due to meeting the necessary physical and chemical requirements. In addition, these residues promote the formation of binders that improve the hydration of Portland cement. This approach improves the physical and mechanical properties of concrete and its durability. It also has economic and environmental advantages, as it uses copper and zinc waste from mining operations. Obtaining copper involves processing minerals from mines, which may contain copper oxides or sulfides. The rock is milled to obtain copper and zinc; these elements are separated using water, air, and other chemicals. The resulting by-products are stored in mining waste deposits that comply with current regulations. As for the research methodology, a deductive approach with applied orientation and a quantitative approach is followed. A retroactive data collection instrument is used to describe and explain the process. The optimal percentage of joint incorporation of copper and zinc residues from mining activity is around 10% and 5%, respectively. If you want to use only copper waste, you could reach up to 30%, while zinc waste can be incorporated in a maximum of 5%. In addition, it is observed that incorporating lead and zinc residues by 40% instead of cement increases compressive strength by 18%.

Thymol-enriched diet alleviates the toxic impacts of zinc oxide nanoparticles on growth performance, blood biochemistry, oxidant/antioxidant status and stress-related genes and histology of liver and gills in Oreochromis niloticus

Dietary natural components emerged as key supplements for protecting fish against aquatic pollutants. In this study, we explored the efficacy of thymol supplementation (1 or 2 g/kg diet) in alleviating the toxic effects induced by exposing Oreochromis niloticus to zinc oxide nanoparticles (ZON) at 1.14 mg/L (equivalent to 1/5th LC50) for 28 days. Relative to control, the fish treated with ZON showed a reduction in the survival rate and growth performance, with the highest zinc residues detected in the liver, followed by muscle and, finally, gills. Alterations were recorded in serum biochemistry reflecting ZON's hepatotoxicity and nephrotoxicity, along with reductions in growth hormone, T3 (triiodothyronine) and T4 (thyroxine). The intestinal amylase, lipase, and protease activities were suppressed with increases in the intestinal Aeromonas and total bacterial counts in the ZON-exposed group. Elevated tissue levels of MDA (malondialdehyde) and PC (protein carbonyl) content, with depletion of the SOD (superoxide dismutase) and CAT (catalase) activities, and GSH (reduced glutathione) levels were also noted in ZON-exposed group, in addition to upregulation of the hepatic HSP-70 (heat shock protein-70), Caspase-3, and P53 (Tumor suppressor protein). Moreover, histomorphological changes were recorded in the ZON-treated fish's liver and gills. Conversely, concomitant administration of thymol with ZON blunted these toxic impacts in a dose-specific manner. Based on these data, thymol could be an effective dietary supplement for stressed fish.

Enhanced recovery of germanium(IV) from zinc residue leachate by tartaric acid functionalized chitosan: Experiments and DFT calculation

The recovery of germanium (Ge) from zinc residue leachate has attracted increasing attention. Herein, this study report on the development of a tartaric acid functionalized chitosan (TA-CS) material serving as an efficient adsorbent for Ge(IV). The introduction of TA resulted in abundant protonatable hydroxyl and carboxyl groups, which endows materials with excellent buffering capacity under acidic conditions. Adsorption kinetics and isotherms showed a fast and efficient adsorption capacity of 57.28 mg/g for Ge(IV). In binary systems, Ge(IV) was preferentially adsorbed over Zn(II), a major coexisting ion, with a separation factor of 3.22. The SEM–EDS FT-IR, XPS and DFT results revealed that mechanisms in combination, including electrostatic adsorption, complexation, hydrogen bonding, and ion exchange, promoted the immobilization of Ge(IV) on TA. The TA-CS material also exhibited great reusability with an adsorption efficiency of 70% after 3 recycles. For the recovery of Ge(IV) in practical zinc residue leachate, the TA-CS material showed superior affinity toward Ge(IV) and a 10-fold higher of adsorption capacity compared to that of pristine chitosan. Together, TA-CS demonstrates that it is a viable and economical material for the separation and preconcentration of Ge(IV) from zinc residue leachate.

Stabilization of glutathione redox dynamics and CYP2E1 by green synthesized Moringa oleifera-mediated zinc oxide nanoparticles against acrylamide induced hepatotoxicity in rat model: Morphometric and molecular perspectives.

The terrible reality is that acrylamide (AA) is a common food contaminant found in a wide variety of commonly consumed foods. This research involves the advancement of a more dependable technique for the bio-fabrication of zinc oxide nanoparticles (ZNPs) through the green method using Moringa Oleifera extract (MO-ZNPs) as an efficient chelating agent for acrylamide (AA). The effects of AA on glutathione redox dynamics, liver function, lipid profile, and zinc residues in Sprague Dawley rats are investigated. Finally, the microarchitecture and immunohistochemical staining of Caspase-3 and CYP2E1 were determined in the liver tissue of rats. Four separate groups, including control, MO-ZNPs (10mg/kg b. wt), AA (20mg/kg b. wt), and AA+MO-ZNPs for 60 days. The results revealed a suppressed activity of glutathione redox enzymes (GSH, GPX,and GSR) on both molecular and biochemical levels. Also, AA caused elevated liver enzymes, hepatosomatic index, and immunohistochemical staining of caspase-3 and CYP2E1 expression. MO-ZNPs co-treatment, on the other hand, stabilized glutathione-related enzyme gene expression, normalized hepatocellular enzyme levels, and restored hepatic tissue microarchitectures. It could be assumed that MO-ZNPs is a promising hepatoprotective molecule for alleviating AA-induced hepatotoxicity. We witnessed changes in glutathione redox dynamics to be restorative. Glutathione and cytochrome P450 2E1 play crucial roles in AA detoxification, so maintaining a healthy glutathione redox cycle is necessary for disposing of AA toxicity.

Unraveling the steric hindrance roles of the phenolic hydroxyl position on the selective Ge(IV) recovery from zinc residue leachate

Understanding the structure–activity relationship between the adsorption performance and accessible adsorption sites plays a vital role in developing efficient adsorbents for Ge(IV) recovery. Herein, three chitosan-based adsorbents were designed by grafting chitosan with p-hydroxybenzoic acid (HBA-CS), 3,4-dihydroxybenzoic acid (DBA-CS), and 3,4,5-trihydroxybenzoic acid (TBA-CS), and the phenolic hydroxyl amounts induced steric effect on Ge(IV) recovery was investigated. The results show that phenolic acids were successfully grafted onto the chitosan surface by an amidation reaction. The adsorption behavior of DBA-CS and TBA-CS conforms to the pseudo-second-order kinetic and Langmuir isotherm models, indicating that it is a single layer adsorption and chemisorption is the main adsorption process. The Ge(IV) recovery performance is correlated with the arrangement of the active adsorption sites and follows the order of TBA-CS > DBA-CS > HBA-CS. The steric effect of TBA-CS is more ideal than that of DBA-CS due to more phenolic hydroxyl groups, which endows it better affinity toward Ge(IV). Additionally, TBA-CS exhibits superior selectivity in the presence of competitive cations and interfering anions, and the adsorption efficiency was not significantly decreased after four regeneration cycles by the acid elution. The chelation adsorption sites for Ge(IV) provided by the o-phenolic hydroxyl groups are the dominant contribution, and the hydrogen bond and ideal steric effect further enhance the adsorption performance of TBA-CS. The structure regulation designed by steric hindrance optimization strategy to achieve high affinity is an attractive approach, which could be extended in the recovery of precious metal ions.

Dunaliella salina Microalga Restores the Metabolic Equilibrium and Ameliorates the Hepatic Inflammatory Response Induced by Zinc Oxide Nanoparticles (ZnO-NPs) in Male Zebrafish.

Simple SummaryDunaliella salina, a type of halophile green unicellular microalgae riches in carotenoids, was used to assess its ability to restore the metabolic equilibrium and mitigate the hepatic inflammation induced by zinc oxide nanoparticles (ZnO-NPs) in the male zebrafish. In our study, after 2 weeks of feeding, the body burdens of zinc residues, fish appetite, intestinal bacteria composition, and energy metabolism were restored. Additionally, the hepatic inflammation and histopathological malformations were ameliorated after D. salina administration.Microalgae are rich in bioactive compounds including pigments, proteins, lipids, polyunsaturated fatty acids, carbohydrates, and vitamins. Due to their non-toxic and nutritious characteristics, these are suggested as important food for many aquatic animals. Dunaliella salina is a well-known microalga that accumulates valuable amounts of carotenoids. We investigated whether it could restore the metabolic equilibrium and mitigate the hepatic inflammation induced by zinc oxide nanoparticles (ZnO-NPs) using male zebrafish which were exposed to 1/5th 96 h-LC50 for 4 weeks, followed by dietary supplementation with D. salina at two concentrations (15% and 30%) for 2 weeks. Collectively, ZnO-NPs affected fish appetite, whole body composition, hepatic glycogen and lipid contents, intestinal bacterial and Aeromonas counts, as well as hepatic tumor necrosis factor- α (TNF-α). In addition, the mRNA expression of genes related to gluconeogenesis (pck1, gys2, and g6pc3), lipogenesis (srepf1, acaca, fasn, and cd36), and inflammatory response (tnf-α, tnf-β, nf-kb2) were modulated. D. salina reduced the body burden of zinc residues, restored the fish appetite and normal liver architecture, and mitigated the toxic impacts of ZnO-NPs on whole-body composition, intestinal bacteria, energy metabolism, and hepatic inflammatory markers. Our results revealed that the administration of D. salina might be effective in neutralizing the hepatotoxic effects of ZnO-NPs in the zebrafish model.

Quantitative determination of the content OF FE, NI, CR, CU, ZN, CD, PB, HG in vegetables and fruits growed in Moldova and assessment of the health risk

Abstract: In samples of fresh vegetables and fruits, food products of domestic production, selected in rural markets, in shops, in preschool institutions of four pilot districts of Moldova, was determined the content of the following heavy metals: copper, zinc, iron, manganese, molybdenum, nickel, lead, cadmium and chrome. Based on the results of a survey of the population of four pilot rural districts, a list of studied products (fresh vegetables and fruits, food of plant origin) was determined. The results of the analysis showed that the investigated heavy metals accumulated in all samples of fresh vegetables, legumes and in products of processing plant raw materials, with the exception of residual amounts of mercury, the content of which was below the detection limit of the method. Taking into account the daily diet of a rural dweller, it can be assumed that the consumption of foodstuffs containing residues of copper, cadmium and zinc exceeding the MPC may have a negative impact on health.

Extraction and recovery of zinc and indium from residue rich in zinc ferrite

Indium is regarded as critical metal due to its scarce availability and increasing demand. The extraction of indium from primary sources is important as an effort to alleviate indium availability given its potential role in sustainable technological advancement. This study introduces a process based on zinc ferrite reduction for the extraction of indium in addition to zinc from zinc residues. Zinc ferrite in zinc residue was partially reduced at 600 °C with a reducing gas containing 10% H2 and the roasting product was subjected to leaching at various conditions to study extraction of target elements. Decomposition of zinc ferrite led to a significant increment on the leaching kinetics of zinc residue. Multiple-step leaching was also explored to enrich the indium concentration in aqueous liquor followed by precipitation of indium. A maximum of 0.121 g/L indium concentration was obtained in multiple step leaching. The effect of temperature, acid concentration, liquid–solid ratio (L/S) and oxalic acid addition on leaching has also been discussed. The proposed process yields an aggregate of about 89% and 88.3% Zn and In extraction respectively along with significant indium concentration in the aqueous leach solution. The precipitation of synthetic solution showed that indium can be precipitated to obtain a concentrate containing about 8% In.

Different trends of Cr, Fe and Zn contents in hair between obese, overweight and normal-weight men.

Overweight and obesity are risk factors for many diseases, nutrition leading to these phenomena is not only a question of disbalance between energy intake and expenditure, but also the presence of micronutrients. In our study, we focused on measuring residues of chromium, zinc and iron in the hair of men with different BMI. Hair samples and anthropometric questionnaires were collected from 45 males. Numbers of subjects and age structure were comparable between the three BMI groups. The determination of metal levels was performed by inductively coupled plasma mass spectrometry after mineralization of the hair. The hair of obese men contained significantly higher chromium (0.096 μg/g vs. 0.045 μg/g, p = 0.0039) and iron (9.42 μg/g vs. 5.84 μg/g, p = 0.0009) concentrations than that of overweight men, but no significant difference between the normal-weight group and the obese group were found. The concentration of zinc was lower in obese subjects compared to overweight subjects (183.5 μg/g vs. 206.2 μg/g, p = 0.038). Also, statistically significant correlations between chromium and iron concentrations in hair and BMI were found (r = 0.307, p = 0.040, r = 0.360, p = 0.015, respectively). According to our results, age did not significantly affect chromium, iron and zinc concentrations in hair. Consistent with some published studies, we have found that obese men have higher chromium and iron concentrations and lower zinc concentrations in hair.

Application of zinc ferrite reduction in the extraction of Zn, Ga and In from zinc refinery residue

Extraction of gallium and indium from zinc refinery residue (ZRR) has continued to attract attention because of different mineralogy of residues and occurrences of trace elements in ZRR. About 90% of gallium is currently extracted from Bayer liquor, whereas, ZRR has been a primary source for indium recovery. The primary production of gallium and indium in USA is currently zero. However, zinc residues are a promising resource for the extraction of critical metals such as gallium, germanium and indium. The major problem in ZRR is the concentration of zinc ferrite (ZF) which is refractory to leaching. The current study introduces a method to enhance the leaching kinetics of ZRR having ZF as major constituent. In this study, ZF was partially reduced with reducing gas containing 10% H2 and the roasting product was then leached under different conditions. The effect of reduction roasting was found to have a significant impact on the leaching kinetics of ZRR. The decomposition of ZF eased the leaching of zinc, gallium and indium. More than 90% extraction of the target elements was achieved with this process. The manuscript also discusses the characterization of ZRR using laser ablation inductively coupled plasma-mass spectrometry (LA ICP-MS), scanning electron microscopy (SEM), x-ray diffraction (XRD) and automated mineralogy.

Evaluation of Partial Digestion as a Strategy for Elemental Analysis of Inorganic Samples by Inductively Coupled Plasma–Optical Emission Spectrometry (ICP OES)—A Proof of Concept Study

This study discusses the application of microwave-assisted sample preparation for inorganic samples using concentrated or diluted HNO3 solutions followed by determination of Al, Ca, Cu, Cr, Fe, K, Mg, Mn, Na, Ni, P, Pb, S, Si, and Zn using inductively coupled plasma–optical emission spectrometry (ICP OES). Aiming the total digestion (reference procedure), samples were decomposed in a heating block using a mixture of 2 mL of 40% v v−1 HF and 5 mL of 14 mol L−1 HNO3. Four digestion mixtures composed by (1) 14, (2) 7.0, (3) 4.0, and (4) 2.0 mol L−1 HNO3 plus 3 mL of concentrated H2O2 were evaluated as alternatives for microwave-assisted digestion of six inorganic samples (partial digestion). Considering all evaluated procedures, quantitative recoveries were obtained applying reference and partial digestion procedures. Therefore, the use of HNO3 dilute solutions as an alternative for HF is a feasible procedure for quantitative analysis of zinc oxide, kaolin, zinc residue, and zinc sulfide. However, tailored procedures must be taken into consideration, since quantitative determination depends on digestion mixture, sample matrix, and analytes.

Efficient extracting germanium and gallium from zinc residue by sulfuric and tartaric complex acid

This paper introduces an efficient extraction method based on organic and sulfuric complex acid system, to achieve the clean recovery of scattered metals from zinc leaching residue. The tartaric (TAR) and sulfuric complex acid significantly improved the leaching of Ge but had little effect on the leaching efficiency of Ga. A maximum extraction efficiency of 93.1% of Ge and 84.3% of Ga, was obtained at a sulfuric acid concentration of 100 g/L, TAR concentration of 20 g/L, leaching time of 1 h, and temperature of 80 °C, with a liquid-solid ratio of 10 mL/g, and a mixing rate of 250 rpm. The leaching process and mechanism were investigated by XRD, SEM, EPMA and UV–Vis. The findings showed that TAR acid plays a key role in the dissociation of the mineral phase containing Ge, as well as the promotion of Ge dissolution. Compared with the conventional sulfuric acid system, the TAR containing complex acid could effectively promote the decomposition of some iron ore phases, like beaverite, in which Ge tends to be embedded and enriched, in association with Fe. Additionally, the improved leaching efficiency of Ge was attributed to the formation of soluble TAR-Ge complexes, which were confirmed by UV–Vis.

Chemical residues in burger and sausage meat products

In this study total of 150 samples of burger and sausage meat products (75 of each) were collected from local and supermarkets in Giza governorate, Egypt. The samples were subjected to determination of residue levels of antibiotics, zeranol, trenbolone, heavy metals (Cadmium, Lead, Zinc and Arsenic) and pesticides (organophosphorus and organochlorine). The study proved that the incidence percent of antibiotics, organophosphorus and arsenic residues were zero in all samples of burger and sausage, while zeranol percent in burger were zero but it was recorded in all sausage samples (75) with mean (0.3721 ppb). The trenbolne was recorded in 75 of both burger and sausage samples with mean (0.1368) and (0.14367) ppb respectively. Lead was present in all samples of burger (75) with mean (0.04844 ppm) while lead was present in 50 samples (67%) of sausage with mean (0.2575 ppm). Cadmium was recorded in 50 samples of burger while not recorded in any of sausage samples. Zinc residues were present in all samples of burger and sausage with mean (0.44784) and (0.6132) ppm respectively. The residues of PP.DDT were recorded in all samples of burger and sausage. The value of PP.DDT in sausage (2.476 ppm) is higher than in burger (1.92004 ppm). Methoxychlor was recorded only in burger with value (49.66062 ppm) while methoxychlor was not recorded in sausage samples. Endrin only recorded in burger with value (0.716 ppm) but not recorded in sausage. PP. DDD was recoded in all burger and sausage samples with value (0.464) and (0.614) ppm respectively.

Characterization and leaching of mechanically activated zinc residue

Zinc extraction from zinc-containing residual (ZCR) was examined with the leach of sulfuric acid of original materials and the materials milled in two different mill systems. For this purpose, vibrating ball mill (VBM) and ring mill (RM) were used. In chemical analysis of ZCR, it was determined that it contains a significant amount of zinc, lead, iron and silver and consisted of mostly CaSO4.2H2O, PbO, SiO2, Fe2O3, ZnFe2O4, Al2FeO4 and PbSO4 mineral phases. It was determined in XRD analysis of samples milled at both mills that peak intensity dramatically decreased when compared to original sample.According to comparative characterization analyses of the milled samples, it was determined that through the increasing grinding time, the particles became agglomerated and an increase in grain size occurred. This situation was also supported by N2-BET and SEM analyses.While zinc extraction value of the sample milled for 1 min, which was obtained at 0.5 M H2SO4 at leach temperature of 25 °C, at the solid–liquid rate of 100:1 and during the leach time of 30 min, was 90% and 60% for, respectively, VBM and RM, zinc of 54% was determined to be extracted in the leach of the original sample, under the same conditions.

Determinación del contenido de zinc en residuos producidos durante el proceso de galvanizado por inmersión

In the hot galvanizing process, remnants are produced that must be removed to avoid a poor quality in the coating of the product. During the hot dip galvanizing process, by-products are obtained both in the tubs and in galvanizing pails, which can be reused. The objective of this study was to recover Zinc from the by- products generated during the hot dip galvanizing process. The study was carried out by characterizing the chemical composition, density, and quantity of the by-products generated during the galvanizing process, which were recovered: Zinc, dross, droplet, and Zinc fines. The monthly average of the by- products generated for one year was 6,900 kg of dross, 5,800 kg of drop and 5,300 kg of zinc fines. 6500 kg of recovered Zinc were obtained. 43% Zinc was recovered. The results were favorable to be able to carry out the recovery of the mineral. It is concluded that it is necessary to work on the recovery of Zinc, since there will be economic savings, and it will also collaborate with the care of the environment by preventing Zinc residues from going to wastewater.

Succession of Dipteran Fly Maggots on Poisoned Pig Cadavers at Nnamdi Azikiwe University, Awka, Nigeria

Dipteran maggots found on a cadaver are used to estimate its time of death but the time may be incorrect if death occurred due to ingestion of poison. Decomposition of a zinc phosphide intoxicated and strangulated pigs (Sus scrofa Linn.) were evaluated in this study. They were deposited in a forest during the rainy season and repeated during the dry season at Awka, Nigeria. Decomposition duration and stages of decay of the pig cadavers were recorded. Maggots found on the cadavers were collected, reared to adulthood and were identified. Similar maggot samples were assessed for residues of zinc and phosphorus with an Atomic Absorption Spectrophotometer. Both pig cadavers completely decomposed within 10 and 14 days during the rainy and dry seasons, respectively. Appearance and emergence of three dipteran maggot families were observed on the cadavers in a successional pattern. Zinc and phosphorus residues were detected in the maggots from the poisoned cadavers while they were not detected in the maggots from the strangled cadavers. The three dipteran maggot families are recommended as a valuable tool in forensic entomology for the estimation of elapsed time of a questionable death and the dipteran bodies would also be useful for toxicological analysis.

Comparative effects of zinc oxide and zinc oxide nanoparticle as feed additives on growth, feed choice test, tissue residues, and histopathological changes in broiler chickens.

Zinc is an essential nutritional trace mineral required for growth and health. The aim of the current work is to compare the effects of bulk zinc oxide and zinc oxide nanoparticles (ZnO-NPs) on the growth performance, feeding behavior, and zinc residues in tissues with the associated histopathological alterations in chicken. Meanwhile, the antibacterial activity against the isolated E. coli O78 strain was evaluated. Ninety Hubbard one-day-aged broiler chicks were divided into 3 groups, 30 each: birds of the 1st group fed a basal ration, those of the 2nd group fed a ration containing zinc oxide at a dose of 3000mg/kg diet, and chicks of the 3rd group are given a ration containing ZnO-NPs at a dose of 90mg/kg diet from 2 to 20days age. The experiment lasted for 35days. Feed choice test was done at the 3rd week of age on another 12 birds. Results revealed that birds fed with ZnO-NPs showed an improvement in body weight compared with the zinc oxide-administered group. There was no reluctance from birds to both diets supplemented with either zinc oxide or ZnO-NPs, with a constant preference to ZnO-NPs diet throughout the 5-min test. The highest levels of zinc were detected in the livers, kidneys, lungs, and muscles in the 1st day following cessation of drug administration. There was no significant effect on the levels of creatinine, uric acid, AST, and ALT. Mild to moderate degenerative changes as well as necrosis could be detected in the livers and hearts following both treatments. In conclusion, nano-zinc oxide could be practically used in broiler feed at a dose of 90mg/kg diet instead of bulk zinc oxide, at a dose of 3000mg/kg diet, with an improved body weight. Both supplements caused no significant effects on serum parameters and had the same antibacterial activity against E. coli O78.

Tracking the first bronze metallurgists of Western Europe: combined use-wear analysis and X-ray fluorescence synchrotron spectroscopy of a stone toolkit from Ploneour-Lanvern (Brittany)

At the turn of the second millennium BC in Europe, the development of copper and bronze metallurgies stimulated major economic shifts, with the emergence of elites and far-reaching diffusion networks. However, the exact organization, techniques, processes, and equipment employed in this early copper and bronze metallurgy still remain poorly understood. In this context, our aim has been to identify the first stone toolkits used by Early Bronze Age metallurgists on a site in western Brittany (France), a region connected to the so-called Atlantic complex. The combination of use-wear analysis and Synchrotron X-ray fluorescence spectroscopy (XRF) imaging highlights a correlation between the distribution of diagnostic use-wear traces (smoothing and micropolishes) related to metal ore processing or metal objet shaping and elemental residues of copper and zinc. These results demonstrate the existence of copper ore processing in western Brittany during the Early Bronze Age (2200–1900 BC). They also highlight the diversity of the stone tools involved in metal production. Finally, this comprehensive methodology underlines the potential of functional analysis of macrolithic tools to reveal the existence of metal production. This is particularly relevant for archeological sites where the structures of metallurgical production are barely visible and often unrecognizable and where metallic objects are rare due to their intensive recycling and diffusion.