Presence Of Toxic Metals Research Articles

Application of dairy wastewater as substrate for bioremediation of coal mine drainage in planted horizontal flow constructed wetland

Coal mine drainage (CMD) is an environmental threat due to its high volume, low pH, presence of toxic metals, and absence of biodegradable organics. The present study aims to treat CMD in a horizontal sub-surface flow constructed wetland (CW) using dairy wastewater as an organic source. CW was planted with Typha angustifolia. Characteristics of synthetic CMD were (except pH, all unit mg/L) pH 1.9; Fe: 100, SO 4 2 − : 1,000, Mn: 6, Zn: 5, Co: 1, Ni: 1, and Cr: 1. CMD was mixed with synthetic dairy wastewater (pH: 5.05, COD: 2,700 mg/L, BOD: 1,600 mg/L) in the ratio of 3:1. Alkalinity of 120–190 mg/L CaCO3 was generated and effluent pH improved from 2.2 to 6.6. Metals precipitated as metal sulfide or hydroxide. Sulfate removal was hindered due to the synergistic toxicity of several metals. Except for Mn, all other effluent parameters were within the discharge limit for disposal in inland surface water.

Effects of Processing on Nickel Content and its Relationship with Proximate Composition in dead fresh and canned tuna fish in Iran

Background: The presence of toxic metals in food can be a risk to food safety and public health. Methods: The Iranian canned tuna was analyzed for nickel level after wet digestion with acids using Graphite Furnace Atomic Absorption Spectrometry (GFAAS). Results: The average concentration of nickel in canned and dead fresh fish found 4.20 ppb and 1.64 ppb. A significant difference in nickel level was observed between canned and dead fresh fish samples in this study. Although the concentration of nickel per g in the fillet after processing was relatively low, but the total amount of nickel in the sample shown change (256.01%). The results in present study showed the protein content in the canned fish increased to 13.17%. The moisture content in the processed fish decreased to 8.80%. The fat content in the canned fish increased to 12.86%. Conclusion: Although the protein and moisture contents significantly increased and decreased respectively after processing, but none of these factors were related to the change in nickel concentration. It may be recommended to regularly monitor the concentration of nickel metal in aquatic food products, so that human health was not at risk.

NtZIP5A/B is involved in the regulation of Zn/Cu/Fe/Mn/Cd homeostasis in tobacco.

Plants grow in soils with varying concentrations of microelements, often in the presence of toxic metals e.g. Cd. To cope, they developed molecular mechanisms to regulate metal cross-homeostasis. Understanding underlying complex relationships is key to improving crop productivity. Recent research suggests that the Zn and Cd uptake protein NtZIP5A/B [Zinc-regulated, Iron-regulated transporter-like Proteins (ZIPs)] from tobacco (Nicotiana tabacum L. v. Xanthi) is involved in the regulation of a cross-talk between the two metals. Here, we support this conclusion by showing that RNAi-mediated silencing of NtZIP5A/B resulted in a reduction of Zn accumulation and that this effect was significantly enhanced by the presence of Cd. Our data also point to involvement of NtZIP5B in regulating a cross-talk between Cu, Fe, and Mn. Using yeast growth assays, Cu (but not Fe or Mn) was identified as a substrate for NtZIP5B. Furthermore, GUS-based analysis showed that the tissue-specific activity of the NtZIP5B promoter was different in each of the Zn-/Cu-/Fe-/Mn deficiencies applied with/without Cd. The results indicate that NtZIP5B is involved in maintaining multi-metal homeostasis under conditions of Zn, Cu, Fe, and Mn deficiency, and also in the presence of Cd. It was concluded that the protein regulates the delivery of Zn and Cu specifically to targeted different root cells depending on the Zn/Cu/Fe/Mn status. Importantly, in the presence of Cd, the activity of the NtZIP5B promoter is lost in meristematic cells and increased in mature root cortex cells, which can be considered a manifestation of a defense mechanism against its toxic effects.

Assessment of elements (toxic and essential) concentrations and methicillin resistance in Staphylococcus aureus strains isolated from raw milk in the Kurdistan province

The presence of residual antibiotics and the excessive accumulation of metals beyond permissible limits in milk represent significant health challenges. This study aimed to analyse the levels of heavy metals and trace elements in raw milk from Kurdistan province using inductively coupled plasma mass spectrometry (ICP‐MS) following digestion via thermal block. Subsequently, the samples were evaluated for contamination with MRSA (methicillin‐resistant Staphylococcus aureus), taking into account the potential correlation between methicillin‐resistant strains and metal accumulation. Finally, milk safety was assessed based on the presence of toxic metals. A total of 180 milk samples were examined. Among them, 13.34% were found to be contaminated with S. aureus, and of those, 62.48% tested positive for MRSA. The metal concentrations (mg/kg) were measured as follows: arsenic 7 × 10−2 ± 6 × 10−3, cadmium 4.70 × 10−1 ± 9.70 × 10−2, lead 7 × 10−2 ± 5 × 10−3, mercury 3 × 10−2 ± 9 × 10−3 and iron 4 × 10−2 ± 9 × 10−3. Interestingly, arsenic, cadmium and iron levels were found to be correlated with the presence of MRSA. Additionally, there was an inverse relationship between toxic metals and essential ones in samples sensitive to methicillin (P < 0.001). The Target Hazard Quotient (THQ) for cadmium is indicated at 9.94. Furthermore, the calculated Carcinogenic Risk (CR) parameters for cadmium and arsenic were 6.06 × 10−3 and 2.22 × 10−4, respectively, suggesting that their concentrations fall within the carcinogenic range. The coexistence of MRSA and metal contamination in raw milk highlights the potential risks linked to its consumption. Consequently, the adoption of rigorous hygiene protocols is imperative to effectively address these concerns.

Fungal biomineralization of toxic metals accelerates organic pollutant removal

Fungal biomineralization plays an important role in the biogeochemical cycling of metals in the environment and has been extensively explored for bioremediation and element biorecovery. However, the cellular and metabolic responses of fungi in the presence of toxic metals during biomineralization and their impact on organic matter transformations are unclear. This is an important question because co-contamination by toxic metals and organic pollutants is a common phenomenon in the natural environment. In this research, the biomineralization process and oxidative stress response of the geoactive soil fungus Aspergillus niger were investigated in the presence of toxic metals (Co, Cu, Mn, and Fe) and the azo dye orange II (AO II). We have found that the co-existence of toxic metals and AO II not only enhanced the fungal biomineralization of toxic metals but also accelerated the removal of AO II. We hypothesize that the fungus and in situ mycogenic biominerals (toxic metal oxalates) constituted a quasi-bioreactor, where the biominerals removed organic pollutants by catalyzing reactive oxygen species (ROS) generation resulting from oxidative stress. We have therefore demonstrated that a fungal/biomineral system can successfully achieve the goal of toxic metal immobilization and organic pollutant decomposition. Such findings inform the potential development of fungal-biomineral hybrid systems for mixed pollutant bioremediation as well as provide further understanding of fungal organic-inorganic pollutant transformations in the environment and their importance in biogeochemical cycles.

Ammonium-based bioleaching of toxic metals from sewage sludge in a continuous bioreactor

The broader reuse of sewage sludge as a soil fertilizer or conditioner is impeded by the presence of toxic metals. Bioleaching, a process that leverages microbial metabolisms and metabolites for metal extraction, is viewed as an economically and environmentally feasible approach for metal removal. This study presents an innovative bioleaching process based on microbial oxidation of ammonia released from sludge hydrolysis, mediated by a novel acid tolerant ammonia-oxidizing bacteria (AOB), Ca. Nitrosoglobus. Over a span of 1024 days, a laboratory-scale bioleaching reactor processing anaerobically digested (AD) sludge achieved an in-situ pH of 2.5 ± 0.3. This acidic environment facilitated efficient leaching of toxic metals from AD sludge, upgrading its quality from Grade C to Grade A (qualified for unrestricted use), according to both stabilization and contaminants criteria. The improved quality of AD sludge could potentially reduce sludge disposal expenses and enable a broader reuse of biosolids. Furthermore, this study revealed a pH-dependent total ammonia affinity of Ca. Nitrosoglobus, with a higher affinity constant at pH 3.5 (67.3 ± 20.7 mg N/L) compared to pH 4.5–7.5 (7.6 – 9.6 mg N/L). This finding indicates that by optimizing ammonium concentrations, the efficiency of this novel ammonium-based bioleaching process could be significantly increased.

Elemental composition and potential health risk of vegetable cultivated in residential area situated close to abandoned gold mine dump: Characteristics of soil quality on the vegetables

The presence of toxic metals in residential areas near abandoned gold mine tailings is a major environmental issue. This study mainly aimed to investigate the elemental distribution of both toxic and essential elements in soils and leafy vegetables (Brassica oleracea) collected from eight different sites around the Davidsonville residential area, located closer to the abandoned Princess gold mine dump, Johannesburg, South Africa. The nutritional value of vegetables in the human diet was determined to assess their value to their health. The vegetables contained metals in the following descending order: Ca > Mg > Ca > Sb > Pb > Fe > Mo > Cr > Se > As > V > Ni > Co > Cd. The bioaccumulation factor (BAF) revealed that vegetables tend to accumulate most metals even (toxic) during the transfer and translocation process. Based on the recommended daily allowance (%RDA) the vegetables showed to contribute 152%, 84% and 75% toward RDA for Se, V and Ca, respectively for most adults and these play a role in human metabolic activities. The vegetables were found to be a good source of essential elements (Ca, Mg, Ni, Na, Fe) but with some traces of toxic metals such as Pb, As and Sb. Based on the health risk assessment, the vegetable posed an adverse health hazard for human consumption due to metals with high HRI >1.

Relationships between high-concentration toxic metals in sediment and evolution of microbial community structure and carbon-nitrogen metabolism functions under long-term stress perspective.

Microorganisms are highly sensitive to toxic metal pollution and play an important role in the material cycling and energy flow of the water ecosystem. Herein, 13 sediment samples from Junchong Reservoir (Guangxi Province, China) were collected in December 2021. The spatial distribution of pollution levels for toxic metals and the effects of toxic metals on the composition, functional characteristics, and metabolism of microorganisms were investigated. The results demonstrated that the area is a proximate area to industrial zones with severity of toxic metal pollution. Their mean concentrations of As, Cu, Zn, and Pb were up to 128.79mg/kg, 57.62mg/kg, 594.77mg/kg, and 97.12mg/kg respectively. There was a strong correlation between As, Cu, Zn, and Pb, with the highest correlation coefficient reaching 0.94. As the level of toxic metal pollution increases, the diversity and abundance of microorganisms gradually decrease. Compared to those with lower pollution levels, the Shannon index in regions with higher pollution levels decreases by up to 0.373, and the Chao index decreases by up to 143.507. However, the relative abundance of Bacteroidota, Patescibacteria, and Chloroflexi increased by 23%, 20%, and 5%, respectively, indicating their higher adaptability to toxic metals. Furthermore, microbial carbon and nitrogen metabolism were also affected by the presence of toxic metals. FAPROTAX analysis demonstrated an abundant reduction of ecologically functional groups associated with carbon and nitrogen transformations under high toxic metal pollution levels. KEGG pathway analysis indicated that carbon fixation and nitrogen metabolism pathways were inhibited with increasing toxic metal concentrations. These findings would contribute to a better understanding of the effects of toxic metal pollution on sediment microbial communities and function, shedding light on the ecological consequences of toxic metal contamination.

Prevalence rates of neurodegenerative diseases versus human exposures to heavy metals across the United States

Novel means are needed to identify individuals and subpopulations susceptible to and afflicted by neurodegenerative diseases (NDDs). This study aimed to utilize geographic distribution of heavy metal sources and sinks to investigate a potential human health risk of developing NDDs. Known or hypothesized environmental factors driving disease prevalence of Alzheimer's Disease (AD), Parkinson's Disease (PD), and amyotrophic lateral sclerosis (ALS) are heavy metals, including arsenic (As), cadmium (Cd), manganese (Mn) and mercury (Hg). Lead (Pb) has been associated with AD and ALS. Analyzable mediums of human exposure to heavy metals (i.e., toxic metals and metalloids), or proxies thereof, include infant blood, topsoil, sewage sludge, and well water. U.S. concentrations of heavy metals in topsoil, sewage sludge, well water, and infant blood were mapped and compared to prevalence rates of major NDDs. Data from federal and state agencies (i.e., CDC, EPA, and the US Geological Survey) on heavy metal concentrations, age distribution, and NDD prevalence rates were geographically represented and statistically analyzed to quantify possible correlations. Aside from an expected significant association between NDD prevalence and age (p < 0.0001), we found significant associations between the prevalence of the sum of three major NDDs with: Pb in topsoil (p = 0.0433); Cd (p < 0.0001) and Pb (p < 0.0001) in sewage sludge; Pb in infant blood (p < 0.0001). Concentrations in sewage sludge of Cd and Pb were significantly correlated with NDD prevalence rates with an odds ratio of 2.91 (2.04, 4.225 95%CI) and 4.084 (3.14, 5.312 95%CI), respectively. The presence of toxic metals in the U.S. environment in multiple matrices, including sewage sludge, was found to be significantly associated with NDD prevalence. This is the first use of sewage sludge as an environmental proxy matrix to infer risk of developing NDDs.

Influence of nutrient, toxic metal and herbicide contents on the soil bacterial communities in tropical vegetable growing areas

The relationship between bacterial diversity and the bioavailability of nutrients, toxic metals and the herbicide oxyfluorfen in a tropical vegetable growing area was evaluated. The study was conducted in a vegetable growing area located in the mountainous region of Rio de Janeiro (Brazil), and samples were collected in areas of vegetable cultivation and areas of environmental reserve. Fertility analyses and determination of the pseudototal levels of toxic metals in the soil samples were performed. The profile of the soil bacterial community was determined by amplification of the 16S rRNA gene and separation by DGGE. The results showed that the levels of toxic metals and elements associated with soil fertility were higher in vegetable production areas. These differences in the physical and chemical characteristics of the soil favored the presence of a greater number of OTUs in the cultivation areas (17.3-27 OTUs) than in the areas of environmental reserve (13-22 OTUs). Therefore, this study demonstrates that the presence of toxic metals and the herbicide oxyfluorfen and the increase in fertility in soils in areas with intensive vegetable cultivation resulting from the intensive management adopted in these areas promotes a differentiation of the bacterial profiles in soils in tropical vegetable growing areas.

ICP-MS İLE BAZI GIDA TAKVİYELERİNDEKİ TOKSİK METALLERİN BELİRLENMESİ

Objective: The presence of toxic metals in foods poses a significant risk to human health. Even low-level exposure to these metals can cause various health problems over a long period of time. In this study, we investigated the levels of toxic metals (Li, Al, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, As, Sr, Cd, Sb, Ba, Pb and Bi) in 34 food supplement samples purchased from pharmacies in Edirne. Material and Method: The samples were digested using HNO3 in a microwave system and the metal content was analyzed using ICP-MS. Result and Discussion: Our results showed that none of the food supplements exceeded Turkish authority limits. Only Cd levels of two food supplements (0.431 μg/g and 0.316 μg/g) exceeded WHO guideline limits. We discussed the potential health effects of these metals and their compounds. Our findings suggest the need for increased regulation and monitoring of food supplements to ensure their safety and quality.

Dietary intake and trophic transfer of cadmium and lead from three daily consumption vegetables in Quito, Ecuador

The presence of toxic metals in vegetables of daily consumption is a concern for human health. Little is known about the concentration of toxic metals in vegetables sold in markets in Quito, Ecuador, and the corresponding risk to the population. This study aimed to measure the concentration of cadmium (Cd), and lead (Pb) in tomatoes, carrots, and lettuce, to estimate the risk for human health, and to determine the trophic transfer factor using Drosophila melanogaster flies. Vegetable samples were obtained from four local markets in Quito to measure the concentration of Cd and Pb (expressed in mg/kg of dry weight) in the vegetables by microwave-assisted acid digestion and atomic absorption spectrophotometry. Drosophila melanogaster flies were fed with contaminated vegetables to determine de trophic transfer factor of metals in the trophic chain. Our results showed the highest accumulation of Pb and Cd occurred in lettuce. In all cases, the Pb and Cd concentrations exceeded the maximum levels established by the Food and Agriculture Organization. However, the daily intake of metals and the health risk index showed no risk from daily consumption. Pb’s trophic transfer factor was excessively high in the tomato-fed flies, showing transference and accumulation in the flies. Cadmium concentration in tomato-fed flies was also the highest among the three vegetables. The trophic chain transfer of toxic metals from vegetables to Drosophila has been observed through a high accumulation of these metals in flies, and this suggests a negative impact on both human health and ecosystems.

Probiotic properties of Bacillus subtilis DG101 isolated from the traditional Japanese fermented food nattō.

Spore-forming probiotic bacteria offer interesting properties as they have an intrinsic high stability, and when consumed, they are able to survive the adverse conditions encountered during the transit thorough the host gastrointestinal (GI) tract. A traditional healthy food, nattō, exists in Japan consisting of soy fermented by the spore-forming bacterium Bacillus subtilis natto. The consumption of nattō is linked to many beneficial health effects, including the prevention of high blood pressure, osteoporosis, and cardiovascular-associated disease. We hypothesize that the bacterium B. subtilis natto plays a key role in the beneficial effects of nattō for humans. Here, we present the isolation of B. subtilis DG101 from nattō and its characterization as a novel spore-forming probiotic strain for human consumption. B. subtilis DG101 was non-hemolytic and showed high tolerance to lysozyme, low pH, bile salts, and a strong adherence ability to extracellular matrix proteins (i.e., fibronectin and collagen), demonstrating its potential application for competitive exclusion of pathogens. B. subtilis DG101 forms robust liquid and solid biofilms and expresses several extracellular enzymes with activity against food diet-associated macromolecules (i.e., proteins, lipids, and polysaccharides) that would be important to improve food diet digestion by the host. B. subtilis DG101 was able to grow in the presence of toxic metals (i.e., chromium, cadmium, and arsenic) and decreased their bioavailability, a feature that points to this probiotic as an interesting agent for bioremediation in cases of food and water poisoning with metals. In addition, B. subtilis DG101 was sensitive to antibiotics commonly used to treat infections in medical settings, and at the same time, it showed a potent antimicrobial effect against pathogenic bacteria and fungi. In mammalians (i.e., rats), B. subtilis DG101 colonized the GI tract, and improved the lipid and protein serum homeostasis of animals fed on the base of a normal- or a deficient-diet regime (dietary restriction). In the animal model for longevity studies, Caenorhabditis elegans, B. subtilis DG101 significantly increased the animal lifespan and prevented its age-related behavioral decay. Overall, these results demonstrate that B. subtilis DG101 is the key component of nattō with interesting probiotic properties to improve and protect human health.

Presence of Toxic Heavy Metals in Hill Water Bodies of Arunachal Pradesh, India – A Health Implication to the Indigenous Population

Water bodies in hilly areas are considered the cleanest in India. They are also sites for household and recreation activities. On the contrary, they are disposal sites for household and toxic industrial wastes. This study evaluates the physio-chemical parameters and the toxic heavy metal content in two water bodies of Itanagar, the capital city of the Himalayan state of Arunachal Pradesh. Physiochemical parameters were evaluated using standard procedures and toxic heavy metal contents were analyzed using Inductively coupled plasma optical emission spectroscopy. The study revealed high dissolved oxygen contents in both water bodies. Other parameters such as alkalinity, carbon dioxide, phosphate, chloride, and nitrate contents were found to be within the permissible limits. However, lead and arsenic were found in trace amounts but below the permissible limits in both water bodies. Cadmium was exactly within the permissible limit whereas, antimony was found to exceed the permissible limit (0.010ppm). Also, chromium (0.070±0.002 ppm) in Ganga Lake and nickel (0.086±0.011 ppm) in Poma River were found to be above the permissible limits. The presence of toxic metals in these natural hilly areas is alarming and can be attributed to increasing anthropogenic activities. Adequate measures and precautions to prevent such contamination activities should be undertaken.

Application of biosurfactant surfactin for the removal of heavy metals from contaminated water and soil via a micellar-enhanced ultrafiltration process

The presence of toxic metals in natural environments presents a potential health hazard for humans, and the removal of toxic metals remains a major challenge. In this study, biosurfactant surfactin was used to remove heavy metals from contaminated soil via a micellar-enhanced ultrafiltration (MEUF) process. Results demonstrate that anionic surfactin with two –COO− groups can bind heavy metals through electrostatic interactions at a pH above its pKa value and then be rejected by the ultrafiltration membranes, resulting in efficient removal of heavy metal ions. By optimizing the operation parameters, over 98% of metals can be removed by adding surfactin at a surfactin/metals ratio of 3:1. Moreover, membrane fouling was characterized and eliminated by an optimized cleaning strategy. Membrane flux recovery can be obtained at 94% without losing separation efficiency. Finally, the validity of the present process was confirmed on real contaminated water and soil, and over 99.2% of metals were removed. Hence, MEUF with surfactin is a reliable and efficient approach for removing heavy metals from contaminated water and soil.

Genotoxicity Assessment and Toxic Metal Contamination of Traditionally used Anthelmintic Medicinal Plants in Assam, India

Medicinal plants possess several metals obtained naturally or through pollution. The study evaluates the genotoxic potentials and the presence of essential elements and toxic metals in Sesbania sesban var. bicolor (leaves), Cyperus compressus (roots), and Asparagus racemosus (roots), which are used as anthelmintics in the traditional medicine of the Santhals in India. A genotoxicity study was performed in rats as per Organization for Economic Co-operation and Development guidelines. Element contents were evaluated using inductively coupled plasma-optical emission spectrometry. Administration of S. sesban var. bicolor (400 mg/kg), C. compressus (700 mg/kg) and A. racemosus (500 mg/kg) did not cause any abnormalities in the chromosomes. Elemental analysis revealed the presence of lead (5.00±0.05, 4.98±0.01, 4.99±0.07 ppm), cadmium (4.99±0.04, 4.90±0.03, 5.00±0.08 ppm) and arsenic (0.98±0.03, 0.41±0.05, 0.92±0.03 ppm), respectively. Although their genotoxic potential was lacking, the presence of toxic metals in them is a cause for concern.

Analysis of heavy metals content in commercially available kratom products in Richmond, Virginia

Kratom is a novel psychoactive substance that has gained popularity within the past ten years. Originating from Southeast Asia, the leaves of the Mitragyna speciosa tree contain two principal alkaloids, mitragynine and 7-hydroxy-mitragynine, that play a key role in opioid-like effects. Due to its effects, the use of kratom products has increased drastically. However, reports describing concerns about the heavy metal content of these products for safe consumption are still scarce. i Twenty-seven kratom products were obtained from tobacco shops in the Richmond, Virginia area, including powders, teas, extracts, and a carbonated beverage. Kratom samples were subjected to an acid digestion followed by Inductively Coupled Plasma-Optical Emission Spectroscopy (ICP-OES) analysis. Aluminum (Al), arsenic (As), copper (Cu), iron (Fe), magnesium (Mg), manganese (Mn), nickel (Ni), and lead (Pb) were quantitated using yttrium as the internal standard. Kratom tea samples were found to have up to 20 times the tolerable upper intake of manganese. Overexposure to manganese can lead to manganism, a syndrome that presents Parkinsonian symptoms including tremors, dystonia, and facial muscle spasms. As kratom products become more mainstream, stricter regulations of these products must be set in place. The presence of toxic metals in kratom products is a public health concern.

Preliminary ionome of the parotoid gland secretion from Rhinella jimi toad

The cururu toad (Rhinella jimi) is an anuran belonging to the fauna of the Brazilian northeast region, which releases a secretion with toxins from your parotoid glands. Although it has some information about secondary metabolites and proteins, the elemental composition of the released secretion is unknown. Therefore, this is the first report on the ionome of the secretion of the parotoid glands from R. jimi, investigating the influences of abiotic factors such as biome, seasonality, and gender. ICP-MS was used for measurements combined with principal component analysis (PCA). A screening of the secretion sample detected 68 elements which the total concentration of 18 elements was determined. PCA revealed that biome and seasonality factors have a greater influence on the ionomic profile of parotoid secretion. The presence of toxic metals in the secretion samples indicates that the R. jimi toad can be considered a potential bioindicator. These findings may contribute to understanding the metabolism, lifestyle, and interaction of the R. jimi toad with environmental factors as well as open new perspectives to investigate the relationships of the ionome with other biomolecules, for example, metalloproteins and their physiological functions.

Adsorption of Cadmium(II) Ions from Aqueous Solutions Using Calcium Molybdate

The presence of toxic metals in aquatic environments poses serious problems for ecosystems and especially for human health. Numerous types of metal oxides have been used to remove these metals and other toxic organic compounds, using adsorption systems. In this work, CaMoO4 was synthesized via coprecipitation and processed for different periods of time using a microwave-assisted hydrothermal system. It was possible to synthesize CaMoO4 on room temperature without any heat treatment. In addition, small processing times in HTMW were able to produce CM with different morphologies. The effect of the reaction time on the morphology of the product and particle size was examined in SEM images. A plausible CaMO4 formation mechanism was proposed based on time and temperature parameters. The potential application of CaMO4 as an adsorbent in water treatment was also investigated and this material exhibited a favorable adsorption performance in the fast removal of cadmium(ii) ions from aqueous solution of 1 mg L-1 concentration. So, CM showing a promising potential for use in environmental remediation.

Presence of toxic metals in toys for domestic animals: Review

Due to the growing number of dogs and cats in Brazilian households, there was also a growing in industrial/commercial sector focused on these pets. With the resignification of these animals within the families, especially with the "infantilization" process, the industry started to produce clothes, treats, and toys for the owners to buy, reflecting in pets their consumerism and the attribution of affective values. Thus, toys have gained prominence due to their environmental enrichment benefits. However, despite the increase in demand, there is no regulatory legislation for toys designed for pets, setting precedents for contamination that endanger the pets' health due to unregulated production. It is suggested the presence of toxic metals in unknown concentrations in these objects, because in toys for children there is the presence of these elements in pre-established concentrations aiming at the safety and integrity of the target audience when purchasing these products. The harmful relevance, especially of toxic metals such as lead (Pb), Mercury (Hg), Cadmium (Cd), and Arsenic (As), can induce acute and chronic toxicosis, triggered by the accumulation of these elements in the tissues, damaging the metabolism and normal physiology of the animal. This literature review aims to point out the possible presence of toxic metals in pet toys, as well as to describe laboratory tests to detect these elements.