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Selenium Compounds in the Waste Water | SpringerLink
The bulk of solid selenides are intermetallic compounds. There are also many organic selenium compounds, and their nomenclature is expanding from year to year. Various methods of analysis are used from all currently available groups. Spectroscopic methods based on the interaction of selenium or its compounds with electromagnetic radiation include:
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Selenium Distribution and Chemistry in Water and Soil
The soluble forms of selenium compounds are mobile and their speciation in soil and water is highly dependent on conditions of specific location, however SeO 4 − has been reported as a major species in oxygenated agriculture water. In past few decades the elevated concentration of selenium in soil and water has been reported as a serious ...
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Review on environmental selenium: Occurrence, public …
Several studies confirmed that organic selenium compounds undergo photo-oxidation in water, and that their mineralization eventually yields inorganic Se species and volatile species of Se, H 2 Se, CH 3 SeH, (CH 3) 2 Se and (CH 3) 2 Se 2 (He et al., 2020; Amouroux et al., 2001; Diaz et al., 2009). In sediments, species are controlled by their ...
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Synthesis Strategies for Organoselenium Compounds and Their Potential
The selenium (Se) element was discovered by a Swedish chemist J. J. Berzelius (1817) in the reddish deposits appeared in the lead chambers in a sulphuric acid plant [].It was named as selenium in honour of Greek Goddess 'Selene' meaning The Moon.Initially, it was thought to be tellurium; but subsequently, it was observed that even though it exhibited very …
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Technical Factsheet on: SELENIU
Selenium concentration in fresh water is usually around 0.02 ppm. The selenium content of surface water is greatly influenced by pH, being high in acidic (pH < 3.0) and in alkaline waters …
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Selenium compounds
The revised IDLH for selenium compounds is 1 mg Se/m3 based on acute toxicity data in animals. Skip directly to site content Skip directly to search. Español ... Biological action and the non-injuriousness level of selenium when it enters the organism together with drinking water. Gig Sanit 35(2):14-19 (in Russian). 6. Pletnikova IP [1970b].
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Biogeochemistry of selenium compounds in the water …
The biogeochemistry of dissolved selenium (Se) was investigated over 3 years (2015–2017) in the subtropical, warm monomictic and meso-eutrophic Lake Kinneret (Sea of Galilee, Israel).
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Selenium Fact Sheet
Selenium is a metal found in natural deposits as ores containing other elements. The greatest use of selenium compounds is in electronic and photocopier components, but they are widely used in other products as well. ... Selenium (Se) contamination of potable water supplies at concentrations above the current MCL of 0.05 milligram per liter (mg ...
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ATSDR Selenium ToxFAQs
This selenium dust will eventually settle over the land and water. ' It also enters water from rocks and soil, and from agricultural and industrial waste. Some selenium compounds will dissolve in water, and some will settle to the bottom as particles. ' Insoluble forms of selenium will remain in soil, but soluble
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National Primary Drinking Water Regulations | US EPA
Long Term 1 Enhanced Surface Water Treatment: Surface water systems or groundwater under the direct influence (GWUDI) systems serving fewer than 10,000 people must comply with the applicable Long Term 1 Enhanced Surface Water Treatment Rule provisions (such as turbidity standards, individual filter monitoring, Cryptosporidium removal ...
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Biogeochemistry of selenium compounds in the water …
The biogeochemistry of dissolved selenium (Se) was investigated over 3 years (2015–2017) in the subtropical, warm monomictic and meso-eutrophic Lake Kinneret (Sea of Galilee, Israel). We monitored seasonal variation and vertical distribution of dissolved total Se (T.Se), inorganic oxyanions (Se(IV) & Se(VI)), reduced Se fraction (Red.Se), organic (Org.Se) …
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Selenium in Drinking-water
Elemental selenium (14) and selenium sulfide (15) are poorly absorbed. After absorption, water-soluble selenium compounds appear to be rapidly distributed to most organs, the highest concentrations being in kidney, liver, spleen, and testes (16,17). Selenium compounds are biotransformed into excretable metabolites, including unknown as
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Selenium Public Health Goal, December 2010
The primary water-soluble selenium forms in aqueous media that are bioavailable to humans are inorganic selenate (SeO 4-2) and selenite (SeO 3-2) ions. Compared to drinking water, food is the major overall source of selenium for humans. Moderately water-soluble organic selenium compounds such as selenomethionine and selenocysteine are
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Selenium & compounds
Some applications for specific selenium compounds follow. Selenium dioxide is the most widely used selenium compound in industry. ... Selenium hydride has a water solubility of 0.70 g/100 mL. Further information. The National Pollutant Inventory (NPI) holds data for all sources of selenium and compounds in Australia. Australia's selenium and ...
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Basic Information about Selenium in Drinking Water
The major sources of selenium in drinking water are discharge from petroleum and metal refineries; erosion of natural deposits; and discharge from mines. A federal law called the …
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Selenium–Fascinating Microelement, Properties and Sources …
Selenium in the forms of both inorganic compounds (Na 2 SeO 3 and Na 2 SeO 4) and organic ones (selenocysteine, selenomethionine, and selenoglutathione) introduced into the organism through food or drinking water results in a significant reduction of chemically induced cancers . Protective effect of selenium occurs after crossing a threshold ...
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Selenium bioaccumulation and speciation in Chironomus …
Most Se accumulated by larvae exposed to selenite or Se-met was retained after 10 d of elimination in clean water. When additional midge larvae were exposed to Se until emergence, Se accumulated during the larval stage was largely retained in the adults. ... Selenium Compounds / pharmacokinetics Selenomethionine / pharmacokinetics* Sodium ...
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Selenium Compound
The reduced form of selenium (selenide) may be formed from water-soluble selenium compounds under acid conditions or in biological systems. The formal oxidation state is –2, and of biological interest are hydrogen selenide, dimethylselenide and trimethylselenonium ions, and selenosugars. The reduced form may also be found in the place of ...
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Speciation of Selenium Compounds | Analytical Sciences
The toxicity and essential nature of selenium in the environment depend on its concentration and on the chemical forms in which it is present. Dissolved inorganic selenium can be found in natural waters as selenides (Se-II), colloidal elemental selenium (Se0), selenite (SeIV) as well as selenate (SeVI). Organic forms of selenium that may be found in organisms, air or in …
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Selenium
The 4 natural oxidation states of selenium are elemental selenium (0), selenide (-2), selenite (+4), and selenate (+6). Inorganic selenate and selenite predominate in water whereas organic selenium compounds (selenomethionine, selenocysteine) are the major selenium species in cereal and in vegetables.
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Mechanochemical synthesis of organoselenium compounds
The selenium-containing compounds are also prevalent in pharmaceutical libraries 2,3,4,5,6, ... Notably, these species exhibit extreme sensitivity to both oxygen and water, leading to their ...
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Selenolanthionine is the major water-soluble selenium compound …
The Cardamine violifolia sample did not contain in considerable amount any of the organic selenium species that are often formed in hyperaccumulator plants; the inorganic selenium content (mostly as elemental selenium) accounted only for <20% of total Se. The most abundant selenium compound, accounting for about 40% of total Se was proved to be …
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Consumer Factsheet on: SELENIU
selenium compounds is in electronic and photocopier components, but they are also widely used in glass, pigments, rubber, metal alloys, textiles, petroleum, medical therapeutic agents, and …
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Selenium Compounds
Water The levels of selenium in groundwater and surface water range from 0.06 to about 400 µg/litre (5–7); in some areas, levels in groundwater may approach 6000 µg/litre (8). …
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Selenium in Drinking-water
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Selenium | Public Health Statement | ATSDR
Selenium levels are less than 10 parts of selenium in a billion parts of water (10 ppb) in 99.5% of drinking water sources tested. People may be exposed to higher-than-normal levels of …
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Basic Information about Selenium in Drinking Water
The greatest use of selenium compounds is in electronic and phOtocopier components. but they are also widely used in glass, pigments, rubber, metal alloys, textiles. petroleum, medical therapeutic agents, and phOtographic emulsions. ... The major sources of selenium in drinking water are discharge from petroleum and metal refineries; erosion of ...
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Heterogeneous interface engineering of cationic vacancy …
Heterogeneous interface engineering of cationic vacancy defects layered double hydroxides and molybdenum-nickel-based selenium compounds to facilitate overall water splitting. Author links open overlay panel Shaobo Zhou, Xiaomin Chen, Tingting Li, Ying Wei ... Water splitting into hydrogen and oxygen involves two half-reactions occurring on ...
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JOURNAL ARTICLE: OCCUPATIONAL HEALTH GUIDELINE …
Selenium and Its Inorganic Compounds (as Selenium) INTRODUCTION This guideline is intended as a source of information for employees, employers, physicians, industrial hygienists, ... Specific gravity (water = 1):3.1 2 Selenium and Its Inorganic Compounds (as Selenium) September 1978. 4. Vapor density (air = 1 at boiling point of sodium
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Selenium | Public Health Statement | ATSDR
Selenium compounds that can dissolve in water are sometimes very mobile. Thus, there is an increased chance of exposure to these compounds. Selenium may enter surface water in irrigation drainage waters. Some evidence indicates that selenium can be taken up in tissues of aquatic organisms and possibly increase in concentration as the selenium ...
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Selenium in the Environment, Metabolism and Involvement …
Selenium in Water. Selenium is also found in water. It originates from atmospheric deposits or soil drainage and sub-soils which are naturally rich in selenium. ... Three groups of selenium compounds can be distinguished in the atmosphere according to their behaviour: volatile organic compounds (DMSe, DMDSe and methaneselenol), volatile ...
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Final Public Health Goal for Selenium
The PHG for selenium is established at 30 parts per billion (ppb) for water-soluble and bioavailable selenium compounds in drinking water. The health-protective level is based …
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Technical Factsheet on: SELENIU
This amount is around 50,000 times greater than the selenium found in seawater. Selenium dioxide is the primary source of problems from industrial exposures since the dioxide forms selenious acid with water or sweat, and the acid is an irritant. Selenium compounds released during coal or petroleum combustion may be a significant source of exposure.
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Selenium
Caswell No, 732; CI 77805; Elemental selenium; Gray selenium; Selenium alloy; Selenium base; Selenium compounds; Selenium dust; EPA Pesticide Code: 072001 ... pharmaceuticals, fungicides, insecticides; component of tobacco smoke. Naturally occurring in small amounts in water and some foods. Soil Screening. Last CHHSL revision: 1/2005 CHHSL ...
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Selenium in the Environment, Metabolism and Involvement …
Selenoproteins, in which selenium is present as selenocysteine, present an important role in many body functions, such as antioxidant defense and the formation of thyroid hormones. Some …
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Selenium in freshwater and marine water
Three oxidation states may occur in the water column, selenium (VI), selenium (IV) and selenium (II). Elemental selenium may also occur in reducing sediments (Maier & Knight 1994). ... (VI) and inorganic selenium compounds. Data were available for total selenium on four taxonomic groups (12 data points), as follows (the pH range was 7.30 to 7.98):
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Selenium Compounds as Novel Potential Anticancer Agents
Chemical structure of inorganic selenium compounds (1—selenite, 2—sodium selenite, 3—selenate, and 4—sodium selenate).During the metabolism of SS in vivo, the formation of hydrogen selenide (H 2 Se) occurs [5,24], which is then methylated forming methylselenol [25,26].The in vivo study concluded that SeL (3 mg/kg body weight (b.w.)) was well tolerated …
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HEALTH EFFECTS
Because of greater bioavailability, water-soluble selenium compounds are probably more toxic than elemental selenium by any route. Selenium is found in nature complexed with multiple compounds, and although various forms are discussed in the profile, many others exist. Some plants, such as alfalfa, yeasts, white grain, and cruciferous species ...
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Selenium contaminated waters: An overview of analytical …
For reasons of human health and ecotoxicity, selenium concentration has to be controlled in drinking-water and in wastewater, as it is a potential pollutant of water bodies. …
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