High Concentrations Of Heavy Metals Research Articles

Effectiveness of depuration with zeolite stone filter to reduce levels of heavy metal lead (Pb) in the feather shell (Anadara antiquata)

Lead toxicity in humans causes neurological disorders, bone metabolism disorders, kidney damage, and impaired liver function. Feather shells that live in marine waters with high Pb heavy metal content can be exposed to these heavy metals, posing a risk to humans who eat shellfish. Depuration is one method that can reduce the Pb content in the body of the feather shell. The depuration process is influenced by several factors, including the length of the depuration and the filter used. This study aims to determine the effective depuration time to reduce the Pb content in feather shells (Anadara antiquata) using zeolite as a filter. This study applied the Latin Square Design (RSBL) method as a research design consisting of four treatments with four replications. The duration of the depuration treatment was 0 hours (P0), 24 hours (P1), 48 hours (P2), and 72 hours (P3). The effectiveness of the depuration of shells using a zeolite filter can be seen in the reduced Pb content in shellfish. The depuration process for 24 hours showed an effective depuration time with a reduction rate of Pb of 1.095 ± 0.05 mg/kg.

Mineral Weathering and Metal Leaching under Meteoric Conditions in F-(Ba-Pb-Zn) Mining Waste of Hammam Zriba (NE Tunisia)

Mining waste is an obvious source of environmental pollution due to the presence of heavy metals, which can contaminate soils, water resources, sediments, air, and people living nearby. The F-(Ba-Pb-Zn) deposit of Hammam Zriba located in northeast Tunisia, 8 km southeast of Zaghouan was intensively exploited from 1970 to 1992. More than 250,000 m3 of flotation tailings were produced and stored in the open air in three dumps without any measure of environmental protection. Thus, in this paper, mineralogical and chemical characterization, especially the sulfide and carbonate phases, were carried out to evaluate the potential for acid mining drainage (AMD) and metal leaching (ML). Conventional analytical methods (XRD, XRF, SEM) have revealed that this mining waste contains on average 34.8% barite–celestine series, 26.6% calcite, 23% quartz, 6.3% anglesite, 4.8% fluorite, 2.1% pyrite, and 0.4% sphalerite. The content of sulfides is less important. The tailing leaching tests (AFNOR NFX 31-210 standard) did not generate acidic leachate (pH: 8.3). The acidity produced by sulfide oxidation was neutralized by calcite present in abundance. Furthermore, the leaching tests yielded leachates with high concentrations of heavy metals, above the authorized thresholds. This high mobilization rate in potential toxic elements (PTE) represents a contamination risk for the environment.

The occurrence of heavy metals and antimicrobials in sewage sludge and their predicted risk to soil — Is there anything to fear?

The study assessed the occurrence of legally-monitored heavy metals and unmonitored antimicrobials in sludge from small, medium, large and very large municipal wastewater treatment plants (WWTPs), and the predicted environmental risk and risk of resistance selection associated with sludge administration to soil. The temporal variations of the studied compounds in sludge and associated risks to soil were determined by sampling over a year.Although the highest concentrations of heavy metals were noted in sludge from the largest WWTP, i.e. from 1.50 mg/kg (mean 1.61 mg/kg) for Cd to 2188 mg/kg (mean 1332 mg/kg) for Zn, the obtained values only reached a few percent of the legal limits. The same WWTP also demonstrated lower concentrations of antimicrobials compared to the smaller ones. The highest concentrations of antimicrobials, ranging from 24.04 μg/kg for trimethoprim to 900.24 μg/kg for tetracycline, were found in the small and medium WWTPs. However, due to lack of regulations at the national and EU levels, the results cannot be compared with legal limits. Principal Component Analysis (PCA), cluster and heatmap analysis separated samples according to WWTP size. Small WWTP demonstrated correlation with antimicrobials (tetracycline, trimethoprim, clindamycin, ciprofloxacin and ofloxacin), while the large and very large WWTP revealed correlations with heavy metals (Cu and Cr).The obtained environmental risk quotients confirmed that the heavy metals did not present a threat, measured either as individual risk quotients (RQenv), cumulative risk (RQcumulative) or risk of mixture of heavy metals (RQmix-metals). In the case of antimicrobials, only tetracycline demonstrated moderate RQenv, RQcumulative and RQmix-antimicrobials in the small WWTP sludge, with values of 0.1 to 1. Our findings highlight the importance of monitoring sewage sludge before soil application, especially from small WWTPs, to reduce the potential environmental impact of antimicrobials. They also confirm our previous data regarding the environmental risk associated with various toxic compounds, including emerging contaminants, in the sludge from small WWTPs.

In vitro toxicity of fine and coarse particulate matter on the skin, ocular and lung microphysiological cell-culture systems

Particulate matter (PM) has been associated with adverse effects on human health, causing allergies, skin and eye irritation and corrosion, respiratory tract irritation, headaches, bronchoconstriction, cardiopulmonary diseases such as asthma, chronic obstructive pulmonary disease (COPD), lung cancer, reproductive problems, premature deaths, and epigenetic changes that lead to a wide variety of cancers, among other health conditions. The air quality in the Medellín - Colombia presents fluctuations that oscillate between the maximum permissible levels established at the national level and by the WHO, which represents a latent risk to people's health. Although important efforts have been made to quantify the different levels of pollution and administrative measures have been established to mitigate air pollution, little research work has been done to establish the relationship between these levels of pollutants and the effects on biological systems. The objective of the present research was to make a morphological and chemical characterization of particulate matter (PM) captured with a commercial air filter and a electrospun nanofiber membrane and evaluate the cytotoxicity of the each PM extracts in monolayer and co-culture models which recreate microphysiological systems of lung, skin and cornea and propose the possible cellular interactions that lead the cytotoxic response of the chemical compounds found in particulate matter in cities. The morphology and elemental chemical characterization were done with scanning electron microscopy coupled with energy dispersive X-ray spectroscopy (SEM – EDS). For the polycyclic aromatic hydrocarbons detection was made with a chromatographic method accoupled to mass spectrometer. Finally, the cytotoxicity was made in monolayers of A549, HEK001, and SIRC cell lines and microphysiological systems consisting of two-cell layer construct to resemble the interaction between fibroblast and epithelial cells that comprises naturally the corneal, skin and lung tissue. We performed three different cocultures models with BALB/3T3 clone A31 as a feeder layer, using porous Transwell® inserts in the in-contact and non-contact way. Monolayer and co-culture models were exposed to coarse and fine PM (1, 2, and 5 mg/mL) and the cell viability was evaluated at 24 h using an MTT assay. The electrospun nanofibers membranes demonstrates higher efficiency to capture PM with different sizes and high concentration of polycyclic aromatic hydrocarbons, heavy metals, and other chemical compounds responsible of many human diseases. Cytotoxic effects of MP were observed in all models at higher concentration; however, models exposed to fine PM exhibited a significant reduction in cell viability compared to those exposed to coarse PM. In addition, multilayer models are more resistant to PM exposure than monolayer models. Furthermore, the study indicated that, depending on the seeding strategy, different results might be observed: the non-contact model showed higher resistance to PM exposure than in-contact for SIRC and HEK001, but A549 monolayers showed the highest viability response. This study demonstrates the usefulness of applying co-culture models to assess environmental pollutant toxicity, in addition to being a potential alternative method to animal testing for risk assessment.

Chlorella pyrenoidosa as a potential bioremediator: Its tolerance and molecular responses to cadmium and lead

Heavy metal contamination negatively affects plants and animals in water as well as soils. Some microalgae can remove heavy metal contaminants from wastewater. The aim of this study was to screen green microalgae (GM) to identify those that tolerate high concentrations of toxic heavy metals in water as possible candidates for phytoremediation. Analyses of the tolerance, physiological parameters, ultrastructure, and transcriptomes of GM under Cd/Pb treatments were conducted. Compared with the other GM, Chlorella pyrenoidosa showed stronger tolerance to high concentrations of Cd/Pb. The reduced glutathione content and peroxidase activity were higher in C. pyrenoidosa than those in the other GM. Ultrastructural observations showed that, compared with other GM, C. pyrenoidosa had less damage to the cell surface and interior under Cd/Pb toxicity. Transcriptome analyses indicated that the “peroxisome” and “sulfur metabolism” pathways were enriched with differentially expressed genes under Cd/Pb treatments, and that CpSAT, CpSBP, CpKAT2, Cp2HPCL, CpACOX, CpACOX2, and CpACOX4, all of which encode antioxidant enzymes, were up-regulated under Cd/Pb treatments. These results show that C. pyrenoidosa has potential applications in the remediation of polluted water, and indicate that antioxidant enzymes contribute to Cd/Pb detoxification. These findings will be useful for producing algal strains for the purpose of bioremediation in water contamination.

KETERGANTUNGAN SEMAI JOHAR (Cassia siamea LAMK) TERHADAP FUNGI MIKORIZA ARBUSKULA PADA MEDIA TAILING TAMBANG EMAS

Tailings are the wastes resulting from mining activities in the amalgamation of mine ore from the ground, with extreme characteristics such as a sand-dominated texture, high Pb heavy metal content, very low availability of carbon and macro nutrients. Consequently, the plants may not able to grow well in the tailings. The application of Arbuscular Mycorrhyza Fungi (AMF) is expected to increase the ability of forest plant seedlings to grow and develop in tailings media. The research was carried out in a greenhouse using johar (Cassia siamea Lamk) seedlings which were inoculated with AMF inoculum: Glomus manihotis, Glomus etunicatum, and mix inoculan (mycofer), and planted in tailings media collected from Pongkor gold mine for 8 weeks. Johar seedlings were able to grow in tailings media and AMF colonization to the seedlings was observed. The compatibility of multi-species inoculum, mycofer, is higher than single AMF inoculum. The height, diameter and biomass growth of johar seedlings in tailings media significantly (p<0.05) increased with AMF inoculation. Johar seedlings have a high dependence on AMF, on tailings media, undicated by value of MIE > 50%, suggesting that the AMF application to johar is very necessary for revegetation activities in tailings media.

Simultaneous immobilization of multiple heavy metal(loid)s in contaminated water and alkaline soil inoculated Fe/Mn oxidizing bacterium

Two strains of Fe/Mn oxidizing bacteria tolerant to high concentrations of multiple heavy metal(loid)s and efficient decontamination for them were screened. The surface of the bio-Fe/Mn oxides produced by the oxidation of Fe(II) and Mn(II) by Pseudomonas taiwanensis (marked as P4) and Pseudomonas plecoglossicida (marked as G1) contains rich reactive oxygen functional groups, which play critical roles in the removal efficiency and immobilization of heavy metal(loid)s in co-contamination system. The isolated strains P4 and G1 can grow well in the following environments: pH 5-9, NaCl 0-4%, and temperature 20-30°C. The removal efficiencies of Fe, Pb, As, Zn, Cd, Cu, and Mn are effective after inoculation of the strains P4 and G1 in the simulated water system (the initial concentrations of heavy metal(loid) were 1 mg/L), approximately reaching 96%, 92%, 85%, 67%, 70%, 54% and 15%, respectively. The exchangeable and carbonate bound As, Cd, Pb and Cu are more inclined to convert to the Fe-Mn oxide bound fractions in P4 and G1 treated soil, thereby reducing the phytoavailability and bioaccessible of heavy metal(loid)s. This research provides alternatives method to treat water and soil containing high concentrations of multi-heavy metal(loid)s.

Induced and natural moss soil crusts accelerate the C, N, and P cycles of Pb[sbnd]Zn tailings

Nutrient deficiency is the primary obstacle in tailing ecological restoration besides high heavy metal content. Biological soil crusts (BSCs) are known for their C and N fixation capabilities and play a crucial role in soil P cycle. BSCs are widespread in tailings and provide a potential ecological restoration approach. In 2022, we carried out an on-site restoration on a PbZn tailing pond in Yunnan Province, China. BSCs were propagated by natural moss crust fragment inoculation. The induced moss crusts (IMCs) were monitored at 0, 45, 90, and 135 days and compared with natural moss crusts (NMCs). The chlorophyll-a content and abundance of biotic organisms increased over time, reaching a peak at 135 days and surpassing that of NMCs. Moss crusts increased the content of C, N, and P nutrients and enzyme activities in the 0.5 cm surface soil. They also reduced the DTPA-extractable Pb content. Moss crusts significantly increased the content of fulvic/humic and protein-like/polyphenol substances, thereby raising the humic index of soil dissolved organic matter (especially NMCs). Furthermore, moss crusts also raised the abundance of nitrification (AOB and Nsr), denitrification (narG, napA, qnorB, and nosZ), and P-cycling (gcd, appA, phoC, phoA, and phoD) genes, especially IMCs after a 135-day inoculation. NMCs exhibited higher moss abundance measured via eukaryotic photoautotrophs. Moss crusts increased photosynthetic bacteria abundance (e.g., Leptolyngbya and Nostocales) and reduced the dominance of chemoautotrophic bacteria, especially the dark sulfide oxidation bacteria (Betaproteobacteriales). This trend was more pronounced in NMCs. Overall, IMCs can recover the functions of NMCs, and in some cases (e.g., abundance and diversity of biotic community, soil nutrient and N & P cycle genes), even surpass them. Our research provides new insights into the tailing ecological restoration.

Study of the Chemical Composition of Soil in the Natural-Technogenic Territory Aidarken

The article presents the results of an analysis of the content of microelements in the soils of the biogeochemical territory of Aidarken. Soil samples for analysis were taken from the top layer of soil cover (0-20 cm) at 3 points in the study area. Chemical analyzes for fertility elements (gross content of nitrogen, phosphorus and potassium, humus, absorption capacity, carbonate content, pH) and analysis for mechanical composition were carried out in the laboratory of the Republican Soil-Agrochemical Station of the Kyrgyzgiprozem State Research Institute under the Ministry of Agriculture and Mineral Resources of the Kyrgyz Republic. The soils of the studied areas belong to the following types: dark Turanian gray soils and mountain brown dry-steppe soils. Antimony, as an accompanying element of mercury, is above the maximum permissible concentration in all areas of the soil cover. High concentrations of individual heavy metals (Pb, Cu, Zn) were found in the tailings area.

Revealing the release and migration mechanism of heavy metals in typical carbonate tailings, East China

Refining the occurrence characteristics of tailings hazardous materials at source is of great importance for pollution management and ecological reclamation. However, the release and transport of heavy metals (HMs) from tailings under rainfall drenching in simulated real-world environments is less well portrayed, particularly highlighting the inherent neutralisation in tailings wastes under superimposed dynamic conditions. In this study, dynamic leaching columns simulating actual conditions were used to observe the release and transport of HMs from tailings under acid rainfall infiltration at spatial and temporal scales. The release rate of trace elements (e.g., As, Cr, Ni, Pb, Cd) is high. Neutralisation in the presence of carbonate rocks in the gangue reduces HMs release intensity from tailings with high heavy metal content, along with the precipitation of iron oxides and chromium-bearing minerals, etc. In addition, the vertical differentiation of HMs is more relevant to physical processes. In the absence of carbonate rocks in gangue, the lowest pH value is reached within 1.2 h after acid rain infiltrates the tailings. At the same time, Cu, Zn and Cd are released significantly from the minerals at the superficial level. The release of As(III) is mainly concentrated in the early and late stages of water-rock contact.

INFLUENCE OF HEAVY METALS ON THE BASIC PHYSIOLOGICAL PROCESSES OF CEREAL AND CEREAL PEGUM CULTURES

At the end of the 20th century, the constant growth of the population and the rapid development of production brought the situation with the state of the environment in many countries and regions of the world to the brink of an ecological crisis. One of the main factors in the degradation of the natural environment is its pollution by various pollutants, among which one of the main places is occupied by heavy metals. Given the above, it becomes clear the relevance of research on the impact of heavy metals on plants. Currently, they are actively held in many countries of the world. The article is aimed at studying the influence of heavy metals on the main physiological processes that occur in plants. The results of studies on the influence of heavy metals on the main physiological processes of grain and leguminous crops are presented. Based on the results of the analysis, it was proven that accumulating in large quantities in plants, heavy metals cause a negative impact on growth, development and other physiological processes. It was established that in the presence of large concentrations of these elements in cereal plants, a decrease in the height of the stem, a decrease in the number of internodes, a decrease in the accumulation of raw and dry biomass, as well as a decrease in the size of inflorescences are observed. The main reasons for the decrease in above-ground biomass productivity in plants are the negative impact of heavy metals on the growth and development of plants and the intensity of photosynthesis. Individual types of plant groups show different ability to accumulate heavy metals. The results of our own research established that in the presence of high concentrations of heavy metals, a decrease in the linear dimensions of leaves was observed in almost all types of plants with which research was conducted. All of the above testifies to various aspects of the effect of heavy metals on metabolic processes and the viability of plants. They affect various functional groups of biologically important substances of the body, displace essential metals from metal-containing complexes, and also generate active forms of oxygen, which often leads to the occurrence of an oxidative explosion in cells and even the death of plants.

Phytoremediation Indices of Water Hyacinth (Eichhornia crassipes) Growing in Panteka Stream, Kaduna, Nigeria

The aquatic environment is incessantly polluted by the release of high toxic concentrations of heavy metals which are bio-accumulative and persistent in nature. This investigation was conducted to assess the phytoremediation potential of water hyacinth (Eichhornia crassipes) growing in Panteka stream, Kaduna where mechanic and farming activities are carried out. Having three sampling points (A, B and C) and pond water, where farming is predominant served as the control site (D) using phytoremediation indices. The root and shoot samples of E. crassipes grown at the sampling points (A, B, C) and the control were analyzed to determine heavy metal concentrations of cadmium (Cd), chromium (Cr), copper (Cu), nickel (Ni), lead (Pb), and zinc (Zn) through Atomic Absorption Spectrophotometry (AAS). The phytoremediation indices were calculated via bioaccumulation coefficient and translocation factor. The results showed that the root samples had higher accumulation of heavy metals than the shoot samples. During the analysis the heavy metal Zn was noted to be accumulated the highest in roots and shoots (335.32 ± 23.6 and 256.52 ± 30.82) mg/kg at sampling point B respectively. In this present analysis heavy metals were translocated efficiently and had bioaccumulation coefficient and translocation factor greater than one. Nickel had the highest bioaccumulation coefficient and translocation factor, and Zn had a translocation factor that was less than one across all samples. This implies that E. crassipes is a potential hyperaccumulator plant for phytoremediation.

Study of Different Biomaterials for Reducing Textile Industry Waste Water Pollution

Textile industry is distributed throughout the country. The manufacturing process of textile industry involve the use of various chemicals and after these processing textile effluent is mix in natural water bodies like river, lakes etc, which shows the impact on water quality changes i.e. cause of water pollution. In this research focus on to change the effluent quality using different biomaterials like saw dust, parthenium, Typha, Maize cob. In textile effluent high content of TSS, COD, Chloride and heavy metals are present. By using these biomaterials the contents of TSS, COD, and Chloride decreases. After treatment of biomaterials change the quality of textile effluent than the before treatment and it becomes pollutant free effluent which does not harm the environment.

Influence of PbCl2 and KCl salt mixture on high temperature corrosion of alloy 625

Aggressive corrosion can occur when firing waste or bio-based fuels, due to the presence of high concentrations of heavy metals, alkali metals, and chlorides. These deleterious compounds deposit on furnace walls and can form mixtures that can rapidly accelerate corrosion. The effect of salts containing lead had not been studied extensively at temperatures lower than 400 °C in nickel-based materials. This study investigates the effect of the individual salts PbCl2 and KCl and their mixture on the high temperature corrosion of alloy 625 at 340 °C and 380 °C. Samples of alloy 625 were covered with individual salts or a salt mixture and exposed to high temperatures in an atmosphere of synthetic air, 20-vol% H2O, and 100 ppm HCl. The results show that the presence of individual salts does not induce observable corrosion attack on alloy 625 after 168 h at any tested temperature. The salt mixture did cause a severe corrosion attack at 380 °C, observed after 24 h of exposure. It is suggested that the salt mixture induces the formation of lead chromates that may prevent or disrupt the formation of a protective chromia scale. It is believed that a key part of the mechanism is the formation of eutectic melts by the interaction of the scale with the salt mixture. Thermodynamic equilibria calculations show that the first melting temperature of PbCl2 and KCl salt mixture after reaction with oxygen can be as low as about 382 °C, and even lower (357 °C) if chromates are present.

Assessment of heavy metal stress in the adaptation strategies of Tulipa luanica growing on serpentine soil through some biomarkers in comparison to Tulipa kosovarica

The aim of this study was to gain a better understanding of how Tulipa luanica adapts to growth in soil with higher concentrations of heavy metals and to assess potential toxic effects using various biomarkers, in comparison to Tulipa kosovarica, a typical serpentine species. For this purpose, we analyzed the concentrations of Al, Ca, Cd, Co, Cr, Cu, Fe, Mg, Mn, Ni, Pb, and Zn in the soil, as well as their accumulation in plants and their associated stress effects. The results indicate that, despite the presence of some metals in very high concentrations in the soil (Al, Fe, Mn, and Ni), they are translocated in minimal amounts within plant organs, particularly in T. luanica. Nearly all metals exhibited significantly higher concentrations in T. kosovarica when compared to T. luanica. Based on the analysis of biomarkers, it is apparent that T. luanica shows greater sensitivity to these conditions. This is evident through the decreased activity of δ-aminolevulinic acid dehydratase and levels of δ-aminolevulinic acid, malondialdehyde, and glutathione observed in T. luanica. It appears that T. luanica effectively restricts the absorption of metals in serpentine soils; however, it experiences oxidative stress induced by these metals, setting it apart from the more resilient T. kosovarica.

Spatial and Temporal Distribution and Source Analysis of Heavy Metals in Agricultural Soils of Ningxia, Northwest of China

The spatial and temporal dynamic monitoring of the heavy metal concentration in agricultural soils can help us to understand the extent and changes of regional soil heavy metal pollution, allowing us safeguard food safety and human health and provide basic data for the prevention and control of heavy metal pollution in agricultural soils. The heavy metals’ concentrations, including Cd, Cr, Cu, Hg, Ni, Pb, Zn, and As, were measured in surface (0–20 cm) soil samples collected in 2017 and 2021 from agriculture land to evaluate their pollution levels in the Ningxia Hui Autonomous Region (Hereinafter referred to as Ningxia), northwest of China. A correlation analysis, principal component analysis, and positive matrix factorization were used jointly to identify possible sources. The results showed that, for most soils, the concentrations of As, Cr, Cu, Ni, Pb, and Zn were lower than the contamination thresholds stipulated by the national guideline. The average concentrations of As, Cd, Zn, and Ni in 2021 were significantly lower than the levels in 2017 (p < 0.05), but the average concentration of Cu was significantly higher in 2021 than in 2017 (p < 0.05), and the average concentrations of Cr, Pb, and Hg did not change significantly during the last five years. According to the pollution assessment index (mean Igeo values), Cd and Hg were found to accumulate in the farmland environment and were the major pollutants in the region, and the hotspots with high concentrations of heavy metals were mainly located in the Yellow River irrigation area in Northern Ningxia. Four main sources of heavy metals in the soils were identified: As mainly originated from natural sources; Pb, Cd, and Ni from atmospheric deposition and industrial activities; Cr, Zn, and Cu from agricultural activities; and Hg from the coal-related industrial activities. The concentration of heavy metals from anthropogenic sources accounted for 77.10% in agricultural soils, indicating the strong influence of this source on soil heavy metal accumulation. These findings provide scientific evidence and valuable information to prevent heavy metal contamination and control of farmland.

Oxidative damage associated with exposure to heavy metals present in topsoils in central Chile.

Exposure to heavy metals may cause the overproduction of reactive oxygen species, generating oxidative stress and consequently, various harms to human health. The soil surrounding the Ventanas Industrial Complex, in Puchuncaví and Quintero municipal districts on the central Chilean coast, contains heavy metal concentrations (As, Cu, Pb, Zn, among others) that far exceed the maximum permissible levels established by Italian soil standards (used as a reference). This study aimed to investigate the potential association between heavy metal exposure in humans and the levels of oxidative stress biomarkers in inhabitants of these locations. We took blood samples from 140 adults living in sites with high concentrations of heavy metals in the soil and compared them with blood samples from 140 adults living in areas with normal heavy metal concentrations. We assessed lipid peroxidation, damage to genetic material, and Total Antioxidant Capacity in these blood samples. Our results indicate an association between oxidative damage and heavy metal exposure, where the inhabitants living in exposed areas have a higher level of DNA damage compared with those living in control areas. Given that DNA damage is one of the main factors in carcinogenesis, these results are of interest, both for public health and for public policies aimed at limiting human exposure to environmental pollution.

Analysis of the heavy metal contents' effect on steroidal saponins and the anti-breast cancer activity of Paris polyphylla var. yunnanensis.

Background: P. polyphylla var. yunnanensis, as a near-threatened and ethnic medicine in China, used to be a key ingredient in traditional Chinese medicine in treatment of traumatic injuries, sore throat, snakebites, and convulsions for thousands of years. However, there were no reports on the inverse relationship between the contents of heavy metals and saponins and its anti-breast cancer pharmacological activity in P. polyphylla var. yunnanensis. Methods: The present study aimed to reveal the characteristics of heavy metal contents and saponins and its anti-breast cancer pharmacological activity and their interrelationships in P. polyphylla var. yunnanensis from different production areas. The contents of heavy metal and steroidal saponins in P. polyphylla var. yunnanensis were analyzed by inductively coupled plasma mass spectrometry (ICP-MS) and the high-performance liquid chromatography technique, respectively. The Pearson correlation was used to study the correlation between saponins and heavy metals. 4T1 mouse mammary tumor cells were selected and cultivated for antitumor studies in vitro. Cell Counting Kit-8 (CCK-8) assay, Hoechst staining, and flow cytometry analysis were used for the examination of the proliferation and apoptosis of 4T1 tumor cells. Mouse breast cancer 4T1 cells were subcutaneously injected into BALB/c mice to construct a tumor model to explore the in vivo inhibitory effect on breast cancer. TUNEL assay and immunohistochemistry were used for the examination of the effect of P. polyphylla var. yunnanensis from different origins on cancer cell proliferation and apoptosis induction in 4T1 tumor mice. Results: Heavy metal contents were highly correlated with the content of steroidal saponins. The overall content of 10 metals in the three producing origins was of the order C3 >C2 >C1. The total content of eight steroidal saponins in the extracts of P. polyphylla var. yunnanensis from three different origins was C1 >C2 >C3. The Pearson correlation study showed that in all of the heavy metals, the contents of Cd and Ba were positively correlated with the main steroidal saponins in P. polyphylla var. yunnanensis, while Al, Cr, Cu, Fe, Zn, As, Hg, and Pb showed a negative correlation. In vitro experiments showed that the extracts of P. polyphylla var. yunnanensis from three origins could inhibit the proliferation and induce cell apoptosis of 4T1 cells in a concentration- and time-dependent manner, especially in the C1 origin. In vivo experiments showed that the extract of P. polyphylla var. yunnanensis from the three origins could inhibit the growth of tumors and induce the apoptosis of tumor cells. In the three origins, C1 origin had the lowest total heavy metal level but the highest total steroidal saponin level. Therefore, it showed a better effect in reducing the expression of the human epidermal growth factor receptor 2 (HER2) and Kiel 67 (Ki67) and increasing the expression of p53 in tumor tissues compared to the other origins. In conclusion, in the three origins, C1 origin exhibits antitumor pharmacological effects in vivo and in vitro which are better than those in the other origins. Conclusion: In this study, we found that with the increase of the heavy metal content, the content of steroid saponins and anti-breast cancer activity decreased. The results showed that the high content of the total heavy metals may not be conducive to the accumulation of steroidal saponins in P. polyphylla var. yunnanensis and lead to the low anti-breast cancer activity. The results of this study suggest that the content of heavy metals should be controlled in the artificial cultivation process of P. polyphylla var. yunnanensis.

Quantitative determination of macro and micro elements and heavy metals accumulated in wild fruits analyzed by ICP-OES method.

The moisture amounts of wild fruits ranged from 51.07 (rosehip) to 88.49% (raspberry (yellow)). Wild strawberry generally contained the highest amounts of P, K and Ca. In addition, the highest Mg result was recorded in wild strawberry, fig and rosehip fruits. P and K amounts of wild edible fruits were recorded between 385mg/kg (blackberry) and 2538mg/kg (fig) to 6114 (medlar) and 18,613mg/kg (wild strawberry), respectively. Depending on the fruit variety and type, the microelements found in the highest amounts were Zn, Cu, Mn and B. Fe resultss of fruits were reported at very low levels. Fe results of wild edible fruits changed between 0.21 (apple) and 1.32mg/kg ((fig). Zn and Cu values of wild edible fruits were recorded between 1.39 (apple) and 16.4mg/kg (fig) to 1.54 (apple) and 18.4mg/kg (wild strawberry), respectively. Cu contents of raspberry (red), raspberry (yellow), blackberry, jujube and medlar fruits were found to be very close to each other. Arsenic (As) contents of wild fruits were recorded to be higher than those of other elements. In addition, some fruits have high heavy metal contents. The heavy metal found in the highest amounts in fruits was As, followed in descending order by Ali Ba, Se, Ni and Pb. The high As content of these fruits is likely due to the As content of the soil where the plants are grown and its contamination with As-rich industrial waste. While As contents of edible wild fruits are detected between 4.21 (rosehip) and 65.7 (wild strawberry), Al results of fruits were reported between 0.03 (rosehip) and 16.0μg/g (mulberry (white)).

Pyrometallurgical recovery of zinc and valuable metals from hazardous blast furnace dust via self-reduction roasting: Phase transformations and morphological evolution

Blast furnace dust (Zn–Fe dust) containing high heavy metal contents is a hazardous waste, and it is derived from the gravity dust removal system and bag dust removal system of a blast furnace. This study elucidated the underlying reasons for the poor separation of Zn and Fe and recommended conditions for the carbothermic reduction roasting process. The results indicated that the poor efficiencies for Zn and Fe separation from Zn–Fe dust were caused by the formation and gradient reduction of wustite (FeyZn1-yO). A higher reduction temperature, longer reduction time and basicity created an advantageous environment for reduction of the wustite intermediate phase and enabled synergistic catalytic reduction of the wustite phase (FeyZn1-yO and FeyCa1-yO). The formation and reduction of the wustite phase (FeyZn1-yO and FeyCa1-yO) are crucial steps in reduction roasting of olivine (ZnyFe2-ySiO4) and ZnxFe3−xO4 with a spinel crystal structure. After adjusting the experimental parameters, the efficiencies for recovery of Zn and Fe from the Zn–Fe dust reached 95.12 % and 96.55 %, respectively.