Journal articles: 'Heavy chemicals'

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Vuong, Ann M., Kimberly Yolton, Joseph M. Braun, Bruce P. Lanphear, and Aimin Chen. "Chemical mixtures and neurobehavior: a review of epidemiologic findings and future directions." Reviews on Environmental Health 35, no. 3 (September 25, 2020): 245–56. http://dx.doi.org/10.1515/reveh-2020-0010.

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AbstractBackgroundEpidemiological studies have historically focused on single toxicants, or toxic chemicals, and neurodevelopment, even though the interactions of chemicals and nutrients may result in additive, synergistic, antagonistic, or potentiating effects on neurological endpoints. Investigating the impact of environmentally-relevant chemical mixtures, including heavy metals and endocrine disrupting chemicals (EDCs), is more reflective of human exposures and may result in more refined environmental policies to protect the public.ObjectiveIn this review, we provide a summary of epidemiological studies that have analyzed chemical mixtures of heavy metals and EDCs and neurobehavior utilizing multi-chemical models, including frequentist and Bayesian methods.ContentStudies investigating chemicals and neurobehavior have the opportunity to not only examine the impact of chemical mixtures, but they can also identify chemicals from a mixture that may play a key role in neurotoxicity, investigate interactive effects, estimate non-linear dose response, and identify potential windows of susceptibility. The examination of neurobehavioral domains is particularly challenging given that traits emerge and change over time and subclinical nuances of neurobehavior are often unrecognized. To date, only a handful of epidemiological studies examining neurodevelopment have utilized multi-pollutant models in the investigation of heavy metals and EDCs. However, these studies were successful in identifying contaminants of importance from the exposure mixtures.Summary and OutlookInvestigators are encouraged to broaden their focus to include more environmentally relevant mixtures of chemicals using advanced statistical approaches, particularly to aid in identifying potential mechanisms underlying associations.

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Rybak, Leonard P. "Hearing: The Effects of Chemicals." Otolaryngology–Head and Neck Surgery 106, no. 6 (June 1992): 677–86. http://dx.doi.org/10.1177/019459989210600611.

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Recent studies of human beings exposed to environmental chemicals, as well as experimental animal studies, have identified a number of chemical agents that are commercial products, chemical intermediaries, waste products, or contaminants that are potentially ototoxic. The classes of compounds discussed in this review include organic solvents, asphyxiant gases, and heavy metals that are present in the environment as Industrial pollutants or byproducts. Both human and animal investigations are summarized in discussing the actions of these ototoxic compounds. The suggested gaps in our knowledge are highlighted to help direct future research.

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Meng, Shengbing, Shuming Wen, Guang Han, Xiao Wang, and Qicheng Feng. "Wastewater Treatment in Mineral Processing of Non-Ferrous Metal Resources: A Review." Water 14, no. 5 (February 24, 2022): 726. http://dx.doi.org/10.3390/w14050726.

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Water used by mining enterprises needs to be comprehensively recovered and utilized to achieve clean production. This requires the effective treatment of mineral processing wastewater. Wastewater produced during non-ferrous metal mineral processing contains a complex mixture of pollutants at high concentrations, making comprehensive treatment difficult. Here, the sources of and hazards posed by wastewater produced during non-ferrous metal mineral processing are introduced and the techniques for removing heavy metal ions and organic chemicals are reviewed. Chemical precipitation and adsorption methods are often used to remove heavy metal ions. Chemical precipitation methods can be divided into hydroxide and sulfide precipitation methods. Organic chemicals are mainly removed using oxidation methods, including electrochemical oxidation, photocatalytic oxidation, and ultrasonic synergistic oxidation. External and internal cyclic utilization methods for treating wastewater produced by mineral processing plants are introduced, and a feasibility analysis is performed.

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Deborah, S., and J. Sebastin Raj. "Bioremediation of heavy metals from Distilleries Effluent using Microbes." Journal of Applied and Advanced Research 1, no. 2 (August 24, 2016): 23. http://dx.doi.org/10.21839/jaar.2016.v1i2.21.

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One of the major universal threats is water pollution. The untreated distilleries effluent discharge into the environment creates a serious problem to the living systems. It may contain carcinogenic aromatics amines, dyes, organic and inorganic chemical compounds. The physicochemical characterization of effluent was collected from Trichy Distilleries & Chemicals pvt Ltd, Tiruchirappalli, Tamilnadu, India and the chemical analyzed in Soil Testing Laboratory, Tiruchirappalli. The effluent was analyzed by different parameters. The physical parameters are BOD, COD, and DO, TDS, pH and electrical conductivity. Heavy metal analysis included Zinc, Lead, Manganese, Arsenic, Iron, Mercury, Copper, Chromium, Cadmium and Nickel. The soil sample was taken from Trichy Distilleries and Chemicals Ltd and analyzed by serial dilution technique. The three microbes such as Escherichia coli, Bacillus subtilis and Pseudomonas putida, were isolated from soil source. The isolated organism was treated with the effluent for various concentrations in various hours. The metal accumulations were identified in soil test lab, Trichy. The hyper accumulations of metal in microbes were identified. The present study explores the effectiveness of bioremediation has a simultaneous removal of Zinc, Lead, Manganese, Arsenic, Iron, Mercury, Copper, Chromium, Cadmium and Nickel from the distilleries effluent. Bacillus subtilis bacterial strains effectively remove the heavy metal from the distilleries effluent.

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Abdullahi, N., E. C. Igwe, and M. A. Dandago. "Heavy metal uptake and stress in food crops: A Review." Agricultural Science and Technology 13, no. 4 (April 2021): 323–32. http://dx.doi.org/10.15547/ast.2021.04.053.

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Abstract. Heavy metal (HM) food contamination is detrimental to food safety and human health. Water scarcity, food shortage, illiteracy, failure to enforce environmental protection laws, and food quality regulations account for human HM contamination. Understanding their uptake pattern in food crops and how the crops behave under excessive concentration of these hazardous chemicals will guide farmers, researchers, and policymakers in devising appropriate control measures that will ensure the production and consumption of safer food crops. Relevant texts published by Science Direct, Springer Nature, and Wiley between January 2018 and December 2020 were cited in this article. The article discussed major factors affecting HM accumulation and the effects of HM stress on yield, physiology, and chemical properties of food crops. Wastewater irrigation, production in contaminated soil, and atmospheric deposit contributed to the contamination. Factors that influence HM uptake are those related to soil and irrigation water qualities and plant properties. The presence of other HMs and chemicals, growing season, crop age, planting method, and food crop type also affect HM uptake in food crops. HM stress affects anatomy, physiology including antioxidant defense mechanisms, nutrient availability and uptake, germination, seedlings development, growth, yield, leaf geometry, root and shoot length, plant genetics, pollination, and chemical composition including moisture content, soluble protein, and pigment content and characteristics.

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Minyard, James P., W. Edward Roberts, and William Y. Cobb. "State Programs for Pesticide Residues in Foods." Journal of AOAC INTERNATIONAL 72, no. 3 (May 1, 1989): 525–33. http://dx.doi.org/10.1093/jaoac/72.3.525.

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Abstract Two U.S. data collection and dissemination programs, FEEDCON and FOODCONTAM, are described. FEEDCON provides information on contamination levels in animal feeds of toxic chemical residues (pesticides, industrial chemicals, heavy metals, mycotoxins, natural plant toxins, salmonella, and therapeutic drug cross-contaminations). FEEDCON data are collected from approximately 40 state feed regulatory agencies, feed manufacturers, and related groups who subscribe ($100-$200 per year) to the program, which is sponsored by the Association of American Feed Control Officials. FOODCONTAM provides similar information, but is limited to pesticides, heavy metals and industrial chemicals (polychlorinated and polybrominated biphenyls, etc.) in human foods. Both programs have been developed and initiated under U.S. Food and Drug Administration contracts with the Mississippi State Chemical Laboratory. Program structures of both are outlined conceptually, and FOODCONTAM is described in detail. FOODCONTAM data-sharing program development is essentially complete, but expansion by incorporating FDA data with State Laboratory data is nearing reality.

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Marchioretto, M. M., H. Bruning, N. T. P. Loan, and W. H. Rulkens. "Heavy metals extraction from anaerobically digested sludge." Water Science and Technology 46, no. 10 (November 1, 2002): 1–8. http://dx.doi.org/10.2166/wst.2002.0275.

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This paper reports on the chemical extraction efficiency in the removal of heavy metals from sludge from an activated-sludge system, which receives as influent both industrial and municipal wastewater. Utilizing a series of chemical extractants in a sequential order comprised the first phase of the research, called sequential chemical extraction (SCE). The work started with the well-known Tessier method followed by Veeken and by Sims and Kline SCE schemes. Afterwards, modified versions of Tessier and Veeken schemes were applied. The second phase, named chemical extraction using pH progressive changes, concerns an alternative to the extraction process. Four acids were tested: nitric, hydrochloric, oxalic and citric and the pH values as well as the time were varied. Some conclusions reveal that although modifying Tessier and Veeken schemes provides more consistent results, SCE is still an imperfect method regarding specificity and selectivity. Besides, it is not advisable to apply one SCE scheme developed for one specific situation to another one, once the accurateness of the method depends on several factors such as sort of material and chemicals, contact time, temperature, etc. The extraction efficiency increases using nitric or hydrochloric acids at low pH values, promoting high extraction efficiency level.

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Shi, Li Na, Xun Xu, Xiao Yan Dou, and Xu Dong Zhao. "The Research Progress of Heavy Metals in PM2.5." Advanced Materials Research 955-959 (June 2014): 1397–404. http://dx.doi.org/10.4028/www.scientific.net/amr.955-959.1397.

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PM2.5 is one of the most important components in air pollution. It is also the focus of the most closely watched at home and abroad. Based on its small size, complex components, and strongenvironmental activity, it can be used as a carrier for chemicals, heavy metals, bacteria, toxins and carcinogens into the body. Then, as a result, it will affect Human Body Health. Heavy metals are important components of PM2.5, and the long-term accumulation of heavy metals in PM2.5 poses a great threat on human health and the environment. This paper reviewed the sources, distribution methods,chemical form, detection methods, disposal way, research progress of heavy metals in PM2.5. As a result, it provided a reference for in-depth study on the future.

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Hamdy, Faris Moayed Ahmed, Abdullatif Mohammed Raouf, Israa Abdulsatar Esmael, Laith Hamza Thuaban, Nadia Fakhry Ibraheem, Hiba Mahmoud Yas, Maher Talib Ali, Zakya Salah Al Deen Salman, Najim Abd Alhusain Jabir, and Tamadhir Neama Yousif. "Mimicking the Crude Oil and Heavy Fuel Oil (HFO) Demulsification Process in Power Plants for Preparing a New Demulsifiers." Journal of Petroleum Research and Studies 10, no. 4 (December 21, 2020): 165–80. http://dx.doi.org/10.52716/jprs.v10i4.376.

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Water–in–oil emulsions are a big challenge in the production and processing of crude oil due to its bad influence on the fundamental and practical aspects of industrial facilities. Researches for decades gave this phenomena a great deal in the planning to construct power plants, refineries, oil companies and other industrial facilities that uses crude oil as a raw material. In order to overcome the disadvantages and hazards of water–in–oil emulsions researchers used chemical, electrical, thermal and mechanical methods individually or in combination. The chemical method has gained the main interest due to its ease of use and economic feasibility. Demulsifiers have been used extensively to solve the problem of water in oil emulsions. The choice of using the right combination of chemicals had been reached after studying many factors such as cost and safety. This research addresses many fundamental and practical aspects regarding demulsifiers and oil demulsification aiming to find the best selection of chemicals that can be used to treat crude oil before using, refining or transporting it. The crude oil in this research had been demulsified and tested by the spectroil test method while the bottle test method had not been used to mimic the demulsification process used in power plant. The work was carried out using two types of oil, crude oil (containing 7 ppm Na and K salts concentration) and heavy fuel oil HFO (containing 12 ppm Na and K salts concentration). The crude oil samples were taken from Al – Hilla 2 power plant while the HFO samples were taken from South Baghdad 2 power plant. The results showed that the water miscible chemicals and chemicals with sufficient solubility that used as a demulsifiers like the acrylic derivatives gave the best demulsification when using more wash water percentage. While the combination of water miscible chemicals and chemicals with sufficient solubility and oil soluble chemicals gave the best results in treating heavy fuel oil while using less wash water percentage.

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BIGELOW, SANFORD W. "Role of the Food Chemicals Codex in Lowering Dietary Lead Consumption: A Review." Journal of Food Protection 55, no. 6 (June 1, 1992): 455–58. http://dx.doi.org/10.4315/0362-028x-55.6.455.

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Because chemicals used in the production of food constitute a significant portion of the U.S. diet, reducing lead levels in them is one of the long-term objectives of the Committee on Food Chemicals Codex, a committee of the Food and Nutrition Board within the Institute of Medicine. The Committee recommends limits for lead, as well as for other heavy metals, arsenic, and other potentially hazardous constituents in chemicals used in food production. Food Chemicals Codex specifications often become legal standards for food chemical purity in the United States and other countries throughout the world. The Committee plans to lower lead limits for food chemicals based on their level of consumption or reported use. Data regarding food chemical use are available from the 1987 Poundage and Technical Effects Update of Substances Added to Food. Because of their high level of consumption, sweeteners constitute a group of food chemicals in which lower lead limits could reduce dietary lead intake. A test method capable of measuring lead at lower levels in certain sweeteners has been published in the third supplement to the Food Chemicals Codex, 3rd edition. The Committee's objective is to ensure that the substances listed in the Food Chemicals Codex do not contribute significant amounts of lead to the diet.

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Oni, T. O., Dokubo Chiweike, Edward C. Destiny, and Iloh O. Victor. "Impact of Heavy Metals and Chemicals on Epigenetic Changes." IPS Intelligentsia Multidisciplinary Journal 1, no. 2 (October 8, 2022): 12–15. http://dx.doi.org/10.54117/iimj.v1i2.4.

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More than 13 million people die each year as a result of environmental contaminants, and it is estimated that up to 24% of diseases are brought on by avoidable environmental exposures. Different environmental chemicals were discovered in the blood and urine of the US population during a screening sponsored by the US Center for Disease Control and Prevention, revealing the level of human exposure to environmental chemicals. A growing body of research indicates that environmental toxins may affect gene expression in ways that affect the development of diseases. The first stages of gene transcription need dynamic chromatin remodeling, which is accomplished by changing how accessible gene promoters and regulatory regions are. These regulatory procedures involve epigenetic factors such as DNA methylation, histone changes, and microRNAs (miRNAs), which in turn regulate gene expression. Exposure to various environmental toxins has been found to create changes in these epigenetic markers, and some of them have been connected to a variety of diseases, along with their causes, treatments, and preventative measures.

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Zhang, Zhien. "Application of inorganic chemicals in industrial wastewater treatment." E3S Web of Conferences 358 (2022): 02058. http://dx.doi.org/10.1051/e3sconf/202235802058.

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With the development of social economy, environmental protection projects have attracted wide attention from all walks of life, especially in industrial development, which can pay attention to environmental problems. Inorganic chemicals have important value in industry and can be well used for scientific treatment of industrial wastewater. It mainly includes the specific application of inorganic chemicals in industrial treatment of printing and dyeing wastewater, heavy metal wastewater, papermaking wastewater, fur, slaughter and other organic wastewater, and electroplating wastewater.Understand the contents of chemical agents themselves, discuss the specific classification of chemical agents, and think about the specific application ways and directions of inorganic chemical agents in the process of industrial wastewater treatment, hoping to have a deeper understanding of inorganic chemical agents, provide a good foundation for the smooth and stable development of industrial wastewater treatment, and show the corresponding technologies to improve the future industrial level.

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J. Shamkhi, Hibatallah, and Tamara K. Hussein. "HEAVY METALS (Pb+2, Ni+2, Zn+2) REMOVAL FROM WASTEWATER USING LOW COST ADSORBENTS: A REVIEW." Journal of Engineering and Sustainable Development 25, Special (September 20, 2021): 3–88. http://dx.doi.org/10.31272/jeasd.conf.2.3.8.

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Pollution with heavy metal ions lead, zinc and nickel resulting from industrial wastewater for various industries such as electroplating industry, batteries, metal refining mines and other factories which discharge into the environment causing damage and pollution to the environment, living organisms, and the majority of heavy metals carcinogenic due to its high toxicity and its containment of dangerous chemicals. Potential danger to human health in all forms by ingestion, inhalation, or skin contact pose by heavy metals ions such as lead, nickel, zinc, and others. To prevent hazards, they must be removed before disposal by different methods such as ion- exchange, chemical separation, filtration, membrane separation, and adsorption. The purpose of this research is to review different low cost adsorbent materials to remove heavy metal ions lead, zinc and nickel from wastewater.

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Li, Jin Ling, Bao Hui Wang, and Ji Dong Yan. "A Study on Compatibility of an ASP Demulsifier with Defoaming Agent." Advanced Materials Research 524-527 (May 2012): 1780–83. http://dx.doi.org/10.4028/www.scientific.net/amr.524-527.1780.

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During the Process of ASP Produced Fluid Treatment, a Considerable Amount of Chemical Agents Were Injected to the Production System due to Problems such as Heavy Emulsion, Scaling and Foaming, Etc. these Chemicals React on each other and Finally Coexist in the Produced Fluid. how about Compatibility between the Chemicals? Will they Strengthen or Weaken their Functions on each other? this Paper Has Confirmed the Effects and their Influences to the Produced Fluid through Lab Tests on Compatibility between Demulsifiers, Defoaming Agents and Proposed a Proper Concentration to Eliminate Influences Caused by the Uncompatibility. Therefore, it Reduces the Effect on the Water Quality.

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Tyurin, Vladimir G., Galina A. Mysova, Nina N. Potemkina, Anton Yu Sakharov, Oksana I. Kochish, and Kirill N. Biryukov. "TOXICOLOGICAL CHARACTERISTICS AND AGROCHEMICAL PROPERTIES OF ORGANIC MINERAL FERTILIZERS BASED ON ANIMAL HUSBANDRY WASTE." Problems of veterinary sanitation, hygiene and ecology 4, no. 44 (2022): 496–501. http://dx.doi.org/10.36871/vet.san.hyg.ecol.202204014.

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The article presents the results of studies of the chemical composition of fresh cattle manure on straw litter, processed manure in the form of compost and granular organic-mineral fertilizer, and also presents data characterizing the level of heavy metals in organic-mineral fertilizers. It has been established that organic mineral fertilizers based on cattle manure have a high nutrient content. According to the chemical composition and content of heavy metals, organic mineral fertilizer meets the national standard of the Russian Federation GOST R 53117-2008 «Organic fertilizers on basis of waste of stock-raising. Specifications» and hygienic standards GN 2.1.7.-2041-06 «Maximum permissible concentrations (MPC) of chemicals in the soil».

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Tarasova, Natalia, Anna Makarova, Andrew Fedoseev, and Danil Borisov. "Global anthropogenic chemicals loads on the environment and the associated chemical footprint and planetary boundaries: a high-resolution regional study." Pure and Applied Chemistry 90, no. 11 (November 27, 2018): 1735–42. http://dx.doi.org/10.1515/pac-2018-0506.

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Abstract Chemical pollution is a problem of global importance. Substances of main concern of chemists worldwide are heavy metals. Heavy metals, such as copper (Cu), nickel (Ni), lead (Pb), vanadium (V), etc., can pose a serious hazard to the environment and human health. Heavy metals are toxic even at very low concentrations. The methodology, described in this paper, considers a migration of chemical pollutants in the environment, in conjunction with the approach used in the Russian regulatory system. Estimations of Maximum Available Concentration overrun show that calculated and experimental data agree to a good extent, particularly for mercury contamination in freshwater bodies. In this study, due to the necessity to obtain data on heavy metals content in water, soil and air, based on available data on emissions, it was decided to use the USEtox model for the simulation of the redistribution of chemicals among such environmental compartments as urban air and air of settlements, fresh waters and coastal sea waters, ocean, agricultural soils and other soils. The USEtox model was chosen because it is available in the free access and its structure can be modified if needed (the model is executed in MS Excel), in addition there is a positive experience in using this model in the combination with Geographic Information Systems (GIS). The algorithm of the calculation of the mass transfer coefficients of chemicals in the hydrosphere and atmosphere, with the use of GIS, is described. This algorithm will provide large amounts of data on the intermedia transfer and transportation of chemical substances with water and air flows and their accumulation in various environmental compartments on a global (the planet Earth) and regional scale for the high-resolution of 0.5°×0.5° grid. In this paper, the case study for the Leningrad Region (the Russian Federation) is presented.

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Kamal, Mohammad Masud, Md Rafiqul Islam Akhand, and Binay Kumar Roy. "Commonly used chemicals in shrimp ghers at Shyamnagar upazila in Satkhira, Bangladesh." Research in Agriculture Livestock and Fisheries 2, no. 2 (September 16, 2015): 343–51. http://dx.doi.org/10.3329/ralf.v2i2.25020.

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The study was carried out to know the purpose of the use of chemicals and current status of chemicals used in various aquaculture activities in Shyamnagar upazila between August 2007 and February 2008. A total of 50 shrimp farmers and chemical sellers were selected for questionnaire interview. Data were collected through PRA tools like questionnaire interview, Focus Group Discussion and key informant interview. All interviewed farmers were male with an average age of 36-45 years and their average family size was 7 members. Commonly used chemicals found in the study area were lime, urea, Triple super phosphate (TSP), Potassium permanganate, Vitamins, Antibiotics, (mainly oxytetracycline and chlorotetreacycline), rotenone, phosphate, phostoxin, sumithion, melathion, timsen, bioaqua, oxymax/oxyflow, aquanarish, aqua clean and théoden. Health management and disease treatment were the major activities where farmers were seen to use a lot of chemicals. Study identified some diseases and conditions like white spot disease, yellow head disease, heavy gill and surface fouling disease, brown spot disease, nutritional disease and environmental disease. This study demonstrated that most of the farmers used chemicals and antibiotics indiscriminately without knowing their mode of action, doses and appropriate procedure of application. Study also shows that farmer used various types of chemicals but did not get benefit only little exception due to shrimp viral disease. The study also highlighted the names and approximate price of aquaculture chemicals available with the chemical sellers in the study areas.Res. Agric., Livest. Fish.2(2): 343-351, August 2015

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Huang, Sui Liang. "Two-dimensional numerical modeling of chemical transport–transformation in fluvial rivers: formulation of equations and physical interpretation." Journal of Hydroinformatics 11, no. 2 (March 1, 2009): 106–18. http://dx.doi.org/10.2166/hydro.2009.025.

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Based on previous work on the transport–transformation model of heavy metal pollutants in fluvial rivers, this paper presents the formulation of a two-dimensional model to describe chemical transport–transformation in fluvial rivers by considering basic principles of environmental chemistry, hydraulics and mechanics of sediment transport and recent developments along with three very simplified test cases. The model consists of water flow governing equations, sediment transport governing equations, transport–transformation equation of chemicals and convection–diffusion equations of sorption–desorption kinetics of particulate chemical concentrations on suspended load, bed load and bed sediment. The chemical transport–transformation equation is basically a mass balance equation. It demonstrates how sediment transport affects transport–transformation of chemicals in fluvial rivers. The convection–diffusion equations of sorption–desorption kinetics of chemicals, being an extension of batch reactor experimental results, take both physical transport, i.e. convection and diffusion, and chemical reactions, i.e. sorption–desorption into account. The effects of sediment transport on chemical transport–transformation were clarified through three simple examples. Specifically, the transport–transformation of chemicals in a steady, uniform and equilibrium sediment-laden flow was calculated by applying this model, and results were shown to be rational. Both theoretical analysis and numerical simulation indicated that the transport–transformation of chemicals in sediment-laden flows with a clay-enriched riverbed possesses not only the generality of common tracer pollutants, but also characteristics of transport–transformation induced by sediment motion. Future work will be conducted to present the validation/application of the model with available data.

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Olugbade, Ebenezer Ajibola, Folorunso Fisola Ojesola, and Abdulwahab Giwa. "Treatment of Borehole Water Using Moringa oleifera Seed and Activated Carbon." International Journal of Engineering Research in Africa 32 (September 2017): 62–75. http://dx.doi.org/10.4028/www.scientific.net/jera.32.62.

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The quality and accessibility of drinking water are of paramount importance to human health. Drinking water may contain disease causing agents and toxic chemicals, and to control the risks to public health, systematic water quality monitoring and surveillance are required. Thousands of chemicals have been identified in drinking water supplies around the world and are considered potentially hazardous to human health at relatively high concentrations. Heavy metals are the most harmful of the chemical pollutants and are of concern due to their toxicities to humans. Moringa oleifera seed acts as a natural coagulant, adsorbent and antimicrobial agent while commercial activated carbon is known for its excellent heavy metal removal. It is believed that Moringa oleifera seed is an organic natural polymer. This work has been carried out to analyse the removal of some heavy metals (lead, nickel, iron, and zinc) from borehole water using moringa seed powder, activated carbon and a combination of the two adsorbents. The results obtained showed that Moringa oleifera is environmentally friendly and suitable for water treatment containing undesirable heavy metals. It was also discovered that all the adsorbents were able to completely remove the lead metal in the water. Furthermore, within the adsorbent dosage limit investigated, only activated carbon could remove all the zinc present in the water. However, there was an indication that higher dosage of the coagulants would be able to remove higher percentage of the other metals. It was also found that, in some cases, an increase in the dosage of some adsorbents led to decrease in the percentage removal of some metals. This was observed to be an indication that there could be the need to take note of the optimum dosages of the adsorbents that need to be used in treating any water. The good performances displayed by these local adsorbents have shown that they could effectively replace the chemicals that have been found to have links with some health problems in human.

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Gusiatin, Zygmunt M., Dorota Kulikowska, and Barbara Klik. "New-Generation Washing Agents in Remediation of Metal-Polluted Soils and Methods for Washing Effluent Treatment: A Review." International Journal of Environmental Research and Public Health 17, no. 17 (August 27, 2020): 6220. http://dx.doi.org/10.3390/ijerph17176220.

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Soil quality is seriously reduced due to chemical pollution, including heavy metal (HM) pollution. To meet quality standards, polluted soils must be remediated. Soil washing/soil flushing offers efficient removal of heavy metals and decreases environmental risk in polluted areas. These goals can be obtained by using proper washing agents to remove HMs from soil. These washing agents should not pose unacceptable threats to humans and ecosystems, including soil composition. Currently, it is desirable to use more environmentally and economically attractive washing agents instead of synthetic, environmentally problematic chemicals (e.g., ethylenediaminetetraacetic acid (EDTA)). The usefulness of novel washing agents for treatment of heavy metal-contaminated soils is being intensively developed, in terms of the efficiency of HM removal and properties of washed soils. Despite the unquestionable effectiveness of soil washing/flushing, it should be remembered that both methods generate secondary fluid waste (spent washing solution), and the final stage of the process should be treatment of the contaminated spent washing solution. This paper reviews information on soil contamination with heavy metals. This review examines the principles and status of soil washing and soil flushing. The novel contribution of this review is a presentation of the sources and characteristics of novel washing agents and chemical substitutes for EDTA, with their potential for heavy metal removal. Methods for treating spent washing solution are discussed separately.

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Awan, Bilal Ahmed, Kashf Mehmood, Asif Ali, Hira Tahir, Iftikhar Ali, Saba Malik, Amjad Ali, Muhammad Sheeraz Javed, and Muhammad Faraz Ali. "Increase Potential of Environmental Stresses and Climatic Risk of Heavy Metals in Plants and Control through Nanotechnology Advances." Haya: The Saudi Journal of Life Sciences 7, no. 2 (February 26, 2022): 51–55. http://dx.doi.org/10.36348/sjls.2022.v07i02.005.

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Different heavy salts accumulated in the soil causing the soil salinity and damage the biological processing occurring in plants such as photosynthesis and light reactions. Climate changes also promote the accumulation of heavy metals by promoting the chemicals substances in the leaves and roots cells that causing the chlorosis. Coal combustion release the large amount of mercury metals that acting as toxic for the plants. There is need to design the biological and mechanical processing the removal of salts and toxic wastes from surfaces in such a way that no eruptions of plant materials occur at the surfaces. Nanotechnology employed the nanoparticles to capture the toxic metals through biological and chemical process that is more reliable and less expensive. A large variety of nanoparticles in the form of nanobased graphene oxides, graphite oxides and CNT, mesoporous silica materials have been used for controlling the pollution caused by heavy metals. These nanoparticles are compatible for the plant growth by suppressing the crop diseases by acting directly on phytopathogens. Therefore, it is reliable for controlling the risk of environmental pollution caused by heavy metals.

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Fricke, Klaus, and Hartmut Vogtmann. "Compost quality: Physical characteristics, nutrient content, heavy metals and organic chemicals." Toxicological & Environmental Chemistry 43, no. 1-2 (April 1994): 95–114. http://dx.doi.org/10.1080/02772249409358021.

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Mabuza, N. T., J. Pocock, and B. K. Loveday. "The use of surface active chemicals in heavy medium viscosity reduction." Minerals Engineering 18, no. 1 (January 2005): 25–31. http://dx.doi.org/10.1016/j.mineng.2004.06.036.

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Osuna-Mascaro, Antonio, Teresa Cruz-Bustos, Benjamin Marie, Antonio G. Checa, and Frédéric Marin. "Heavy Metals in Mollusc Shells: A Quick Method for their Detection." Key Engineering Materials 672 (January 2016): 340–45. http://dx.doi.org/10.4028/www.scientific.net/kem.672.340.

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It is known for a long time that calcified tissues secreted by aquatic or terrestrial invertebrates – such as mollusc shells – have the ability to concentrate large amounts of pollutants, in particular heavy metals. In the present paper, we have found an extremely rapid and easy procedure to qualitatively detect the putative presence of heavy metals in shells, without having to use sophisticated techniques such as Wavelength Dispersive Spectroscopy, atomic adsorption spectroscopy or ICP-MS. Our method rests on the capacity of the silver enhancement chemicals that are traditionally used in immunogold localization experiments to increase the size of heavy metal nanoparticles, whatever the chemical element. It goes as follows: freshly broken pieces of shells that are suspected to contain traces of heavy metals are simply incubated 15 minutes in few drops of a silver enhancement solution (British Biocell International), and, after short rinsing and drying, the shell fragments are directly observed with a tabletop Scanning Electron Microscope, under back scattered electron (BSE) mode without any further preparation. Heavy metals nanoparticles are detected as bright spots. Our method is extremely fast (about half an hour in total), and may be used as a quick check for pre-selecting series of calcified samples prior to the quantitative analysis of their heavy metal content.

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Kholmurodov, Temurali, Firdavs Aliev, Oybek Mirzaev, Aleksey Dengaev, Arash Tajik, and Alexey Vakhin. "Hydrothermal In-Reservoir Upgrading of Heavy Oil in the Presence of Non-Ionic Surfactants." Processes 10, no. 11 (October 24, 2022): 2176. http://dx.doi.org/10.3390/pr10112176.

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The most widely applied methods to unlock heavy oil and natural bitumen resources in the world are still based on steam injection techniques. Improving the efficiency of hydrothermal processes poses a great challenge. The co-injection of various additives is practiced to lower the steam-to-oil ratio (SOR), viscosity alteration and to improve heavy oil properties. Organic solvents, non-condensable gases, air and surfactants are the preferred chemicals to be combined with steam. This study provides an investigation of the surfactant-assisted hydrothermal upgrading of heavy oil at 200 °C. The thermal stability and salt resistivity of two non-ionic surfactants (SA–3 and Biolub Green) were investigated. Moreover, the improved performance of the surfactants was established by performing an SARA analysis, elemental analysis, FT-IR spectroscopy, and EPR analysis, and by studying the viscosity reduction degree. The experimental results showed that surfactants lead to the in-depth destructive hydrogenation of the high-molecular components of heavy oil such as resins and asphaltenes. However, the content of light fractions increased. According to the results of the elemental analysis, the surfactants assist in the hydrodesulphurization of heavy oil. Overall, the physical and chemical consequences of hydrothermal upgrading in the presence of surfactants led to the irreversible viscosity reduction of heavy oil.

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Lukyanov, Alexey I., Ekaterina V. Dakhova, and Ludmila P. Mayorova. "Assessment of snow cover pollution by heavy metals as one of the methods of atmospheric air monitoring on the example of settlements in the Far East." RUDN Journal of Ecology and Life Safety 30, no. 3 (September 13, 2022): 407–16. http://dx.doi.org/10.22363/2313-2310-2022-30-3-407-416.

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The relevance of the work is due to the study of technogenic load by studying snow cover in small settlements of the Far East. The possibility of including this method in the monitoring system of small cities of the Far East as an additional means of assessing atmospheric air pollution is being considered. The article presents an analysis of the content of heavy metals in the melt of snow collected in the port of Vanino in the Khabarovsk Territory. The concentration of heavy metals in meltwater obtained after melting snow samples was compared with MPCd-c of chemicals in the water of water bodies of economic, drinking and cultural water use and MPCf-s of chemicals in water of fishery significance. The results obtained indicate an excess of MPCf-s for some heavy metals. These studies correlate with previous surveys (modeling, calculation of dust load) and allow us to assert that the analysis of snow cover can be successfully used in monitoring atmospheric air for various purposes.

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Iov, Tatiana, Mihnea Costescu, Madalina Diac, Daniel Tabian, Sofia Mihaela David, Anton Knieling, and Simona Irina Damian. "Dangerous Chemical Agents: General and Odonto-Stomatological Aspects with Importance in Forensic Toxicology." Revista de Chimie 70, no. 5 (June 15, 2019): 1829–34. http://dx.doi.org/10.37358/rc.19.5.7225.

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In the heavy and light industry, the food and pharmaceutical industry, there are chemicals that contain metals with high toxic potential. Toxicity of metals is due to the harmful effect in certain forms and doses. Some metals become toxic when they form soluble compounds or in a certain chemical structure at certain doses (eg lead, mercury and candium). Not only heavy metals are toxic metals, there are also light metals that can become toxic, some of which are essential elements (iron, selenium, copper, chromium, zinc) and metals used therapeutically in medicine (aluminum, bismuth, gold, gallium, lithium and silver) may have negative effects when administered in large quantities or the elimination from the human body is deficient. Metal poisoning occurs through nutrition, medication, environmental factors. Most professional pollutants with intraoral manifestations appear in the heavy industry. The oral cavity is an entry gate for various toxic pathogens, so intoxications can be detected early due to the manifestations inside the mouth.

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Wang, Xue Feng, Jia Jia Xie, and Ying Hui Liu. "RFID Application in Dangerous Chemicals Safety Management." Applied Mechanics and Materials 198-199 (September 2012): 1261–64. http://dx.doi.org/10.4028/www.scientific.net/amm.198-199.1261.

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RFID, a radio frequency identification technology, it is a kind of communication technology, through the radio signal to identify specific targets and to read and write data, without the need for recognition system with specific target is established between the mechanical or optical contact. Dangerous chemicals as a special commodity, has greatly improved the life of people, but its inherent danger to human survival threat. Based on RFID technology, this paper proposed some ways and methods of dangerous chemicals management, to strengthen the management of dangerous chemicals and reduce the heavy accident to occur with the people's lives and property loss.

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Gîrd, Cerasela Elena. "Heavy metals in medicinal plants – myth or true?" Farmacist.ro 5, no. 1 (October 30, 2019): 24–26. http://dx.doi.org/10.26416/farm.190.5.2019.2631.

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At present, the society is facing a paradox, namely, as the technology and the industry are more efficient, the consumption need for various chemicals increases, which determines the evolution of adverse effects on human health, but also on the environment. The presence of heavy metal residues in medicinal plants raises a big problem at the moment regarding the safety of the combination in the treatment, especially for long periods, of those food/nutritional supplements obtained from contaminated raw materials.

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Bin, Zhao, Cheng Yongqiang, Guo Cuilian, Liu Maoke, Yao Puyu, and Zhou Yang. "Outlook and overview of microplastics pollution in ecological environment." E3S Web of Conferences 143 (2020): 02027. http://dx.doi.org/10.1051/e3sconf/202014302027.

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Microplastics are attracting more and more attention as a new type of pollutant in the ecological environment. Microplastics are difficult to degrade because of their unique physical and chemical properties. Some microplastics adsorbed toxic chemicals (e.g. heavy metals or organic pollutants) will cause a series of toxicological effects in organisms. This paper summarized the research progress in microplastics from the aspects of the types, distribution, detection and the toxicological effects. In addition, future research directions were also proposed and discussed.

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Jang, A., Y. S. Choi, and In S. Kim. "Batch and column tests for the development of an immobilization technology for toxic heavy metals in contaminated soils of closed mines." Water Science and Technology 37, no. 8 (April 1, 1998): 81–88. http://dx.doi.org/10.2166/wst.1998.0311.

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Laboratory tests of various chemical treatments for the immobilization of copper, nickel, and lead in soils typically found at mine facilities were evaluated. A series of batch, adsorption tests, and lab-scale continuous column tests were conducted to optimize the design parameters for the full-scale immobilization processes. The laboratory test program consisted of batch and column experiments to measure the leachability and subsequent immobilization of the single heavy metal, Cu2+, Pb2+, and Ni2+ in an artificial soil which was composed of bentonite and quartz fine sand. Batch equilibrium methods were used to test the ability of a large number of chemical additives to react with heavy metals in contaminated soil. The two best treatment chemicals (CaO and Na2S) for each soil-metal combination were selected for more detailed columns studies. The column tests were carried out in the acidic pH range. According to the results of the column leaching test, it was found that the degree of heavy metal leaching is highly dependent on pH. An adsorption test was performed under acidic conditions (pH 4) to evaluate bentonite as an additive to treat acid mine drainage (AMD).

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Waoo, Ashwini A., Swati Khare, and Sujata Ganguly. "Toxic effect of different lead concentrations on in vitro culture of Datura inoxia." Journal of Scientific and Innovative Research 3, no. 5 (October 25, 2014): 532–35. http://dx.doi.org/10.31254/jsir.2014.3512.

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Metals are the part of natural constituents of soil but industrial activities such as mining and smelting of ores, electroplating work, gas exhaust, energy and fuel production, fertilizer and pesticide application, and municipal waste results in enormous amount of increase in their natural concentrations in soil. Hazardous compounds or chemicals such as heavy metals, oils and battery metals from industries and organic solvents are major soil pollutants. These substances get deposited to the soils of the neighboring area and pollute them by changing the chemical and biological properties of soil of that area. The aim of this research was to identify some interesting accumulators which may associate an important biomass production with an effective heavy metal accumulation, absorption and translocation and their tissue culture approach. This research is mainly focused on the ability of some native plants to accumulate and tolerate high concentrations of heavy metals which are often associated in polluted areas. It has been found that Datura inoxia has the capacity to accumulate the heavy metals in its part. The in vitro culture of Datura inoxia shows better response in Lead supplementing M. S. Media. Although lead is a toxic heavy metal for plants, but Datura inoxia shows good response at higher concentration..

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Dumitriu (Gabur), G. D., C. Teodosiu, I. Morosanu, O. Jitar, and V. V. Cotea. "Quantification of toxic metals during different winemaking stages." BIO Web of Conferences 15 (2019): 02024. http://dx.doi.org/10.1051/bioconf/20191502024.

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Heavy metals in beverages can constitute serious problems to human health. Consumption of wine may contribute to the daily dietary intake of pollutants, especially of toxic (heavy) metals. These compounds are also known as priority pollutants due to their potential toxic effects, if concentrations are not kept under allowable limits. Many characteristics such as: quality, origin, aroma and health safety of wine are influenced by environmental and anthropogenic factors. Hence, the contamination of wine by priority pollutants may occur at different stages of vine-growing, due to the application of agricultural chemicals, or at different stage of winemaking and ageing, because of the extended contact of wine with winemaking equipment materials (aluminium, brass, glass, stainless steel and wood, etc.), or chemicals used for cleaning and sanitation. The aim of this study is to identify and quantify the heavy metal ions from red wines. A particular focus was attributed to Zn and Cd from destemming-pressing-filtration-bottling stages in Fetească neagră grape variety from Cotnari vine growing region of Romania. Results indicated that heavy metals were linked to diverse Zn and Cd sources and complexes during the winemaking processes. Concentration of Zn and Cd were generally higher in must than in wine, although heavy metals concentrations were lower than the limits recommended by the International Organization of Vine and Wine for human health safety.

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Huang, Ying, YongXia Li, Jian Yang, MinMin Xu, Bo Sun, FuWei Gao, and Ning Wang. "Harmful Chemicals in Soil and Risk Assessment of an Abandoned Open Dumpsite in Eastern China." Journal of Chemistry 2015 (2015): 1–10. http://dx.doi.org/10.1155/2015/297686.

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The concentrations of pollutants in soil samples collected in and around a dumpsite in Heze, Shandong, China, were investigated, and the potential ecological and health risks of these pollutants were assessed. Seventeen soil samples from five different locations were analysed for pollution characteristics, and the target pollutants included inorganic pollutants and heavy metals as well as volatile organic compounds/semivolatile organic compounds (VOCs/SVOCs). Results showed that the mean concentration level of each pollutant from the interior area was relatively higher than that from the boundary area of the dumpsite. Inorganic pollutants and heavy metals were detected in all of the soil samples. According to potential ecological risk assessment with environmental background values of Shandong as screening values, heavy metals in majority of the samples pose low ecological risk to the ecosystem except Hg. Hg poses a considerable or very high risk because of its high levels of accumulation. In consideration of future land use pattern, human health risks derived from environmental exposure to heavy metals were assessed. Carcinogenic risk and noncarcinogenic hazards for adults are acceptable, while noncarcinogenic hazards for children exceed the safety threshold. The health risks are primarily attributed to oral exposure to As and Cr.

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Tarasova, Natalia P., Anna S. Makarova, Stanislav F. Vinokurov, Vladimir A. Kuznetsov, and Pavel I. Shlyakhov. "Green chemistry and sustainable development: approaches to chemical footprint analysis." Pure and Applied Chemistry 90, no. 1 (January 26, 2018): 143–55. http://dx.doi.org/10.1515/pac-2017-0608.

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AbstractThe methods to monitor the distribution of chemicals in the biosphere and to estimate the impact of chemicals on the biosphere are necessary to reach Sustainable Development Goals (SDGs). The paper presents the examples of methods to measure the concentration of heavy metals (including rare earth elements) and to rank them by the level of hazard to human health on different scales. The megacity scale presents the investigation of the impact of heavy metals on the small water bodies using water contamination index (WCI); and the investigation of snow contamination to estimate the level of short-term seasonal emission of heavy metals and rare earth elements. The 2nd part of the paper presents approaches to mitigate the exposure to mercury on the regional scale: the estimation of the current concentrations of mercury in atmospheric air, natural soils, and fresh waters using UNEP/SETAC USEtox model, as well as the estimations of the variations in the concentrations of mercury for the year 2045 in the federal districts of the Russian Federation, based on representative concentration pathways (RCPs) scenario and Minamata Convention scenario.

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Wolffers, Mirjam, Gisela Weibel, and Urs Eggenberger. "Waste Wood Fly Ash Treatment in Switzerland: Effects of Co-Processing with Fly Ash from Municipal Solid Waste on Cr(VI) Reduction and Heavy Metal Recovery." Processes 9, no. 1 (January 13, 2021): 146. http://dx.doi.org/10.3390/pr9010146.

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In Switzerland, waste wood fly ash (WWFA) must be treated before deposition on landfills due to its high pollutant load (Cr(VI) and heavy metals). Acid fly ash leaching, the process used for heavy metal recovery from municipal solid waste incineration fly ash (MSWIFA), represents a possible treatment for heavy metal depletion and Cr(VI) reduction in WWFA. The co-processing of WWFA with MSWIFA during acid fly ash leaching was investigated in laboratory- and industrial-scale experiments with different setups. Of interest were the effects on heavy metal recovery efficiency, the successful outcome of Cr(VI) reduction and consumption of neutralizing chemicals (HCl, H2O2). Detailed chemical and mineralogical characterization of two WWFA types and MSWIFA showed that MSWIFA has higher concentrations in potentially harmful elements than WWFA. However, both WWFA types showed high concentrations in Pb and Cr(VI), and therefore need treatment prior to deposition. Depending on the waste wood proportion and quality, WWFA showed chemical and mineralogical differences that affect leaching behavior. In all experimental setups, successful Cr(VI) reduction was achieved. However, WWFA showed higher consumption of HCl and H2O2, the latter resulting in a particularly negative effect on the recovery of Pb and Cu. Thus, co-processing of smaller WWFA portions could be expedient in order to diminish the negative effects of Pb and Cu recovery.

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Averina, Yu M., G. E. Kalyakina, V. V. Menshikov, Yu I. Kapustin, and V. S. Boldyrev. "Neutralisation Process Design for Electroplating Industry Wastewater Containing Chromium and Cyanides." Herald of the Bauman Moscow State Technical University. Series Natural Sciences, no. 84 (June 2019): 70–80. http://dx.doi.org/10.18698/1812-3368-2019-3-70-80.

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Manufacturing processes in the electroplating industry employ hazardous chemicals and generate hazardous waste, including hexavalent chromium compounds and heavy metal cyanides. We designed a reagent-based treatment technology that can remove these contaminants and is relatively simple to implement and maintain. The technology features low reagent consumption but high treatment efficiency and simplifies separating precipitates from the treated effluent. The paper presents a detailed description of how to neutralise electroplating shop wastewater. We propose a system of organizational and technological measures to improve chemical safety.

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MALINOWSKA, E. "IMPACT OF AGRICULTURAL CHEMICALS ON SELECTED HEAVY METALS ACCUMULATION IN HERB PLANTS." Applied Ecology and Environmental Research 14, no. 3 (2016): 479–87. http://dx.doi.org/10.15666/aeer/1403_479487.

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Antwi, Samuel O., Elizabeth C. Eckert, Corinna V. Sabaque, Emma R. Leof, Kieran M. Hawthorne, William R. Bamlet, Kari G. Chaffee, Ann L. Oberg, and Gloria M. Petersen. "Exposure to environmental chemicals and heavy metals, and risk of pancreatic cancer." Cancer Causes & Control 26, no. 11 (August 21, 2015): 1583–91. http://dx.doi.org/10.1007/s10552-015-0652-y.

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Shimaoka, Takayuki, Koji Oku, Kentaro Miyawaki, Masataka Hanashima, Yoshihiro Hori, Katsumi Matsumoto, Kiyoharu Furukawa, and Toshihito Uchida. "Stability of Hazardous Heavy Metals in Landfilled Fly Ash Immobilized by Chemicals." Journal of the Japan Society of Waste Management Experts 9, no. 6 (1998): 264–73. http://dx.doi.org/10.3985/jswme.9.264.

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Li, Ke, Nicholas Miwornunyuie, Lei Chen, Huang Jingyu, Paulette Serwaa Amaniampong, Desmond Ato Koomson, David Ewusi-Mensah, Wencong Xue, Guang Li, and Hai Lu. "Sustainable Application of ZIF-8 for Heavy-Metal Removal in Aqueous Solutions." Sustainability 13, no. 2 (January 19, 2021): 984. http://dx.doi.org/10.3390/su13020984.

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Water is life, and clean-water demand is increasing daily as a result of rapid population growth and industrial evolution. Nevertheless, due to the inadequate supply and availability of new water sources, there is a need for effective, sustainable removal of contaminants for wastewater reuse. Several treatment approaches that include chemical, physical, and biological methods have been thoroughly tested, with biological treatment being regarded as the most cost-effective and environmentally friendly method. However, the presence of heavy metals and complicated chemicals that are nonbiodegradable limits the use of this cost-effective approach. In this paper, we review the sustainable application of a cheap, water-stable metal-organic framework, the zeolitic imidazolate framework (ZIF-8), with an easier synthesis approach for heavy-metal removal in aqueous solutions. In this review, we discuss the removal efficiency in terms of adsorption capacity, describe the underlying mechanism behind the adsorption capacity of ZIF-8, present a sustainable synthesis approach, and make vital suggestions to aid in the future application of ZIF-8 for the removal of heavy metals.

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Lestari, Lestari. "POLUTAN LOGAM BERAT DALAM EKOSISTEM MANGROVE." OSEANA 43, no. 3 (October 30, 2018): 40–51. http://dx.doi.org/10.14203/oseana.2018.vol.43no.3.64.

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HEAVY METAL POLLUTANTS IN MANGROVE ECOSYSTEM. Mangrove is an unique tropical ecosystem with the marine, riverine, terrestrial and atmosphericcomponents influencing the occurrence, speciation, bioavailability and fate of trace chemicals. Mangrove ecosystem are one of the most threatened tropical environment due to habitat loss, aquaculture expansion, overharvesting and increase of pollution load. In this paper, the role of mangrove to act as a sink of pollutants, accumulation and biomagnifications of heavy metals is discussed.

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Chen, Song, Cancan Wu, Shenshen Hong, and Qianqian Chen. "Assessment, Distribution and Regional Geochemical Baseline of Heavy Metals in Soils of Densely Populated Area: A Case Study." International Journal of Environmental Research and Public Health 17, no. 7 (March 27, 2020): 2269. http://dx.doi.org/10.3390/ijerph17072269.

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To understand the content, pollution, distribution and source and to establish a geochemical baseline of heavy metal elements in soil under the influence of high-density population, the concentrations of heavy metal elements Cr, Mn, Co, Ni, Cu, Zn, As, Cd, Hg, Pb and Fe were determined in 23 soil samples in Suzhou University, and geo-accumulation index, enrichment factor, principal component analysis, spatial analysis and regression analysis were completed. The results showed the following: The elements Cu and As were slightly polluted, while the other heavy metal elements were not. The elements Cd, Cu, Ni and As in soils were mainly caused by agricultural activities of chemical fertilizer, whereas the elements Zn and Hg were impacted by the chemicals and batteries. The heavy metal elements in the north were lower than in the south of the campus, as a whole. The enrichment of elements Cu, As and Cd was caused by the east–west river on the campus, and the enrichment of the elements Mn, Ni and Zn was induced by the reservoir. Biochemical experiments and vehicle parking influenced the spatial enrichment of Cr, Co and Pb, while domestic waste led to the spatial differentiation of Hg concentrations. The regression curve between heavy metal elements and Fe was established, and the background values of the heavy metals Cr, Mn, Co, Ni, Cu, Zn, As, Cd, Hg and Pb are 50.90, 489.37, 11.76, 37.74, 55.70, 58.22, 20.07, 0.09, 0.08 and 24.13 mg/kg, respectively.

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Geraskin, Mikhail Mikhailovich, Zhanna Nikolaevna Bakanova, Vasily Ivanovich Kargin, Natalia Nikolaevna Ivanova, and Nikolay Nikolaevich Neyaskin. "Accounting of heavy metals in agricultural land use." BIO Web of Conferences 52 (2022): 00029. http://dx.doi.org/10.1051/bioconf/20225200029.

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People use many chemicals in their economic activities, which leads to the fact that they become involved in a cycle of anthropogenic transformations of the environment. It was proved that microelements and heavy metals are the most toxic among pollutants. Microelements in the arable layer of the soil depend on the type of soils, their location and content in soil-forming rocks. The studies revealed that the content of heavy metals in the soil in all cases is lower than the APC (MPC). The products obtained in the test areas are safe in relation to the content of heavy metals. Adaptive landscape farming systems can serve as an additional and significant step in optimizing the environmental situation when the soils are contaminated with heavy metals.

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Al-Otaibi, Ahmad M., and Meshal Al-Samhan. "Correlation and Analysis of Operating Temperature Data for Direct Olefin Conversion from Heavy Crude." Journal of Physics: Conference Series 2179, no. 1 (January 1, 2022): 012026. http://dx.doi.org/10.1088/1742-6596/2179/1/012026.

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Abstract Data analytics is a complex process of examining available data to reveal information such as hidden arrangements and correlations that can help enhance production or cost cutting decisions. The world’s demand and production of olefins are now higher than any other chemicals especially light olefins. This demand is supported by the fact that currently, Crude Oil-to-Chemicals (COTC) is an influential driver and a strong trend of high interest to all integrated refineries and chemical producers. Zeolite-based catalyst is a major cracking catalyst used in the industry, where Y-zeolites have progressively attracted attention as good adsorbents and stable acid catalysts, and are characterized by large, essentially spherical and internal cavities. This work focuses on analyzing operating data and correlating reaction temperatures for heavy crude to enhance the production of olefin using zeolite based catalyst. The prepared Y-zeolite was characterized for Specific surface area (SSA), total pore volume (TPV), average pore diameter (APD), and pore area (PA) according to the ASTM methods. The prepared catalyst showed a large pore diameter 211 Å and a high specific area of 425.6 m2/g, then the prepared catalyst was tested under varying conditions in a 250-mL autoclave-type reactor equipped with a stirrer, online Gas Chromatography (GC) and a gas sampling port. Different samples of crude with catalyst were tested at 380-450 °C and analysed via the online GC, where high peaks of ethylene and propylene were observed mainly at 430 °C reaching 3000 ppm wt. Moreover, the accumulative data of ethylene and propylene production from the experiments were recorded.

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Gómez Marrugo, Diana, Deisy León Méndez, Jorge Puello Silva, Clemente Granados Conde, and Glicerio León Méndez. "Metal fumes: exposure to heavy metals, their relationship with oxidative stress and their effect on health." Producción + Limpia 14, no. 2 (March 6, 2020): 8–20. http://dx.doi.org/10.22507/pml.v14n2a1.

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Metalworking industry, especially welding processes, is one of the most economically active in the world. Transformation and joining of metal parts are used in many labor activities, such as construction. Welding uses different metal mixtures to carry out bonding through various processes. The greatest chemical risk associated with welding is the emission of metallic fumes, which enter the body mainly through the respiratory system, producing effects in all systems of the human body. Therefore, studies are needed to support the control of exposures to these chemicals in the workplace, as well as the limitation of emissions to the environment, by governments, employers, and workers.

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Бирюков, I. Biryukov, Самылина, E. Samylina, Трифонов, and Konstantin Trifonov. "Analysis of Accumulation of Heavy Metals and Iron in Soils (on Vladimir Region Example)." Safety in Technosphere 3, no. 2 (April 25, 2014): 7–14. http://dx.doi.org/10.12737/3665.

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Work is devoted to studying of accumulation of heavy metals and iron in soils related to Kovrov (Vladimir region) residential suburb. Gross content and forms of heavy metals and iron, taken out by acetate-ammonium buffer solution and nitric acid were defined during researches. The obtained data have been compared to operating values of maximum-permissible and approximately-admissible concentration for various types of soils, and also to the background content of chemicals in soils.

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Rattan, Saniya, Changqing Zhou, Catheryne Chiang, Sharada Mahalingam, Emily Brehm, and Jodi A. Flaws. "Exposure to endocrine disruptors during adulthood: consequences for female fertility." Journal of Endocrinology 233, no. 3 (June 2017): R109—R129. http://dx.doi.org/10.1530/joe-17-0023.

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Endocrine disrupting chemicals are ubiquitous chemicals that exhibit endocrine disrupting properties in both humans and animals. Female reproduction is an important process, which is regulated by hormones and is susceptible to the effects of exposure to endocrine disrupting chemicals. Disruptions in female reproductive functions by endocrine disrupting chemicals may result in subfertility, infertility, improper hormone production, estrous and menstrual cycle abnormalities, anovulation, and early reproductive senescence. This review summarizes the effects of a variety of synthetic endocrine disrupting chemicals on fertility during adult life. The chemicals covered in this review are pesticides (organochlorines, organophosphates, carbamates, pyrethroids, and triazines), heavy metals (arsenic, lead, and mercury), diethylstilbesterol, plasticizer alternatives (di-(2-ethylhexyl) phthalate and bisphenol A alternatives), 2,3,7,8-tetrachlorodibenzo-p-dioxin, nonylphenol, polychlorinated biphenyls, triclosan, and parabens. This review focuses on the hypothalamus, pituitary, ovary, and uterus because together they regulate normal female fertility and the onset of reproductive senescence. The literature shows that several endocrine disrupting chemicals have endocrine disrupting abilities in females during adult life, causing fertility abnormalities in both humans and animals.

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Abdullahi, N., E. C. Igwe, M. A. Dandago, and N. B. Umar. "HEAVY METALS IN FOOD CROPS: IDEAL SOURCES AND ROLES OF URBAN AGRICULTURE IN FACILITATING THEIR CONSUMPTION- A REVIEW." FUDMA JOURNAL OF SCIENCES 5, no. 2 (June 20, 2021): 34–45. http://dx.doi.org/10.33003/fjs-2021-0502-520.

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The qualities of agricultural soil and water are diminishing continuously due to the rigorous anthropogenic activities currently stocking the soil with a lot of toxic chemicals including heavy metals. Heavy metals are highly persistent and non-biodegradable, control of their contamination is very tricky to handle. Their presence in soil and water is detrimental to food crops and humans. Various sources of heavy metals contaminants and the role of urban food production on human heavy metal contamination were discussed.Heavy metals have their way into the soil and food crops through wastewater irrigation and production in contaminated soil. The habitual heavy metals contamination sources for food crops are wastewater irrigation, abuse of agrochemicals, production in the contaminated field, atmospheric deposit when foods are exposed to contaminated air, and unethical mining activities. Agricultural soil in urban and peri-urban areas are heavily contaminated with heavy metal due to various anthropogenic activities. Wastewater irrigation intensify the contamination by supplying the soil with more heavy metals. The heavy metals are passed to food during production and subsequently to humans after consumption.

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Rajendran, A., D. Ragupathy, M. Priyadarshini, A. Magesh, P. Jaishankar, N. S. Madhavan, K. Sajitha, and S. Balaji. "Effective Extraction of Heavy Metals from their Effluents Using Some Potential Ionic Liquids as Green Chemicals." E-Journal of Chemistry 8, no. 2 (2011): 697–702. http://dx.doi.org/10.1155/2011/202380.

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Synthesis of nine Task Specific Ionic liquids (TSILs), their characterization using1H NMR spectral studies and other physical properties and potential applications in the removal of certain heavy metals such as Nickel, Iron, Zinc, Copper and Lead has been studied. The removal of these heavy metals from the industrial effluents / contaminated water bodies using these ionic liquids has been proved to be more successful than conventional methods such as precipitation, cementation, reverse osmosis, ion exchange and adsorption.

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Journal articles on the topic 'Heavy chemicals'

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