The Experts below are selected from a list of 9195 Experts worldwide ranked by ideXlab platform

Jenny Dussangarzon - One of the best experts on this subject based on the ideXlab platform.

  • high efficiency mercury sorption by dead biomass of lysinibacillus sphaericus new insights into the treatment of contaminated water
    Materials, 2019
    Co-Authors: David J Vegapaez, Ricardo E. Rivas, Jenny Dussangarzon
    Abstract:

    Mercury (Hg) is a toxic metal frequently used in illegal and artisanal extraction of gold and silver which makes it a cause of Environmental Poisoning. Since biosorption of other heavy metals has been reported for several Lysinibacillus sphaericus strains, this study investigates Hg removal. Three L. sphaericus strains previously reported as metal tolerant (CBAM5, Ot4b31, and III(3)7) were assessed with mercury chloride (HgCl2). Bacteria were characterized by scanning electron microscopy coupled with energy dispersive spectroscopy (EDS-SEM). Sorption was evaluated in live and dead bacterial biomass by free and immobilized cells assays. Hg quantification was achieved through spectrophotometry at 508 nm by reaction of Hg supernatants with dithizone prepared in Triton X-114 and by graphite furnace atomic absorption spectroscopy (GF-AAS). Bacteria grew up to 60 ppm of HgCl2. Non-immobilized dead cell mixture of strains III(3)7 and Ot4b31 showed a maximum sorption efficiency of 28.4 µg Hg/mg bacteria during the first 5 min of contact with HgCl2, removing over 95% of Hg. This process was escalated in a semi-batch bubbling fluidized bed reactor (BFB) using rice husk as the immobilization matrix leading to a similar level of efficiency. EDS-SEM analysis showed that all strains can adsorb Hg as particles of nanometric scale that can be related to the presence of S-layer metal binding proteins as shown in previous studies. These results suggest that L. sphaericus could be used as a novel biological method of mercury removal from polluted wastewater.

R E Ferner - One of the best experts on this subject based on the ideXlab platform.

  • episodes of Environmental Poisoning worldwide n j langford r e ferner
    2016
    Co-Authors: R E Ferner, West Midlands
    Abstract:

    The environment is composed of chemical substances, many of which are poisonous if present in large amounts, and some of which are poisonous even in small quantities. Within the industrial ised world, specific concentrations of highly dangerous chemicals may be localised to a certain area, vastly increasing the risk to the local environment. Although highly regulated by legislation such as the Control of Major Accident Hazards Regulations 1999 (COMAH), and agencies such as the Health and Safety Executive (HSE) and the Environment Agency (in England and Wales), or the Scottish Environment Protection Agency (SEPA) (in Scotland), industry has been a common source of Environmental contamination. Additionally, as we discuss below, manufacturing of chemicals is not the only industrial process that places the environment at risk. Environmental Poisoning can also result from the transport, storage, and secondary uses of the primary product. Small scale releases of toxic chemical substances are common within the industrialised world.1 Their impact is usually limited by effective statutory controls and efficient emergency services, but the combination of system failures can lead to disaster. In limiting the impact of such chemical releases, effective communication is required not only between the operator and emergency serv ices but also from the emergency services to the public. Without such communication, panic may ensue, leading to emergency and hospital services being overwhelmed and prevented from effec tively pursuing their roles. The most serious events usually have an immediate impact. Probably the best known example of this was Bhopal, where 2500 people died. However, chemical disasters can also occur where the release of toxins or contamination of products is insidious. This complicates both the detection of the cause of the Poisoning and also the management of the environment and those poisoned. At the extreme, a low level continuing release of products can result in the accumulation of a poison both within the environment and within humans, leading to overt symptoms only decades after exposure to the chemical started. Such problems are becoming increasingly common. The time course of the Environmental impact is of major importance in determining Environmental damage from chemical incidents. We also distinguish between naturally occurring Environmental damage by chemicals; damage from human chemical activity; and Poisoning through food and drink, which might be susceptible to legislative control and which requires rather different responses. We com ment briefly on chemical weapons and warfare.

  • episodes of Environmental Poisoning worldwide
    Occupational and Environmental Medicine, 2002
    Co-Authors: N J Langford, R E Ferner
    Abstract:

    The environment is composed of chemical substances, many of which are poisonous if present in large amounts, and some of which are poisonous even in small quantities. Within the industrialised world, specific concentrations of highly dangerous chemicals may be localised to a certain area, vastly increasing the risk to the local environment. Although highly regulated by legislation such as the Control of Major Accident Hazards Regulations 1999 (COMAH), and agencies such as the Health and Safety Executive (HSE) and the Environment Agency (in England and Wales), or the Scottish Environment Protection Agency (SEPA) (in Scotland), industry has been a common source of Environmental contamination. Additionally, as we discuss below, manufacturing of chemicals is not the only industrial process that places the environment at risk. Environmental Poisoning can also result from the transport, storage, and secondary uses of the primary product. Small scale releases of toxic chemical substances are common within the industrialised world.1 Their impact is usually limited by effective statutory controls and efficient emergency services, but the combination of system failures can lead to disaster. In limiting the impact of such chemical releases, effective communication is required not only between the operator and emergency services but also from the emergency services to the public. Without such communication, panic may ensue, leading to emergency and hospital services being overwhelmed and prevented from effectively pursuing their roles. The most serious events usually have an immediate impact. Probably the best known example of this was Bhopal, where 2500 people died. However, chemical disasters can also occur where the release of toxins or contamination of products is insidious. This complicates both the detection of the cause of the Poisoning and also the management of the environment and those poisoned. At the extreme, a low level continuing release of products can result in …

David J Vegapaez - One of the best experts on this subject based on the ideXlab platform.

  • high efficiency mercury sorption by dead biomass of lysinibacillus sphaericus new insights into the treatment of contaminated water
    Materials, 2019
    Co-Authors: David J Vegapaez, Ricardo E. Rivas, Jenny Dussangarzon
    Abstract:

    Mercury (Hg) is a toxic metal frequently used in illegal and artisanal extraction of gold and silver which makes it a cause of Environmental Poisoning. Since biosorption of other heavy metals has been reported for several Lysinibacillus sphaericus strains, this study investigates Hg removal. Three L. sphaericus strains previously reported as metal tolerant (CBAM5, Ot4b31, and III(3)7) were assessed with mercury chloride (HgCl2). Bacteria were characterized by scanning electron microscopy coupled with energy dispersive spectroscopy (EDS-SEM). Sorption was evaluated in live and dead bacterial biomass by free and immobilized cells assays. Hg quantification was achieved through spectrophotometry at 508 nm by reaction of Hg supernatants with dithizone prepared in Triton X-114 and by graphite furnace atomic absorption spectroscopy (GF-AAS). Bacteria grew up to 60 ppm of HgCl2. Non-immobilized dead cell mixture of strains III(3)7 and Ot4b31 showed a maximum sorption efficiency of 28.4 µg Hg/mg bacteria during the first 5 min of contact with HgCl2, removing over 95% of Hg. This process was escalated in a semi-batch bubbling fluidized bed reactor (BFB) using rice husk as the immobilization matrix leading to a similar level of efficiency. EDS-SEM analysis showed that all strains can adsorb Hg as particles of nanometric scale that can be related to the presence of S-layer metal binding proteins as shown in previous studies. These results suggest that L. sphaericus could be used as a novel biological method of mercury removal from polluted wastewater.

Ricardo E. Rivas - One of the best experts on this subject based on the ideXlab platform.

  • high efficiency mercury sorption by dead biomass of lysinibacillus sphaericus new insights into the treatment of contaminated water
    Materials, 2019
    Co-Authors: David J Vegapaez, Ricardo E. Rivas, Jenny Dussangarzon
    Abstract:

    Mercury (Hg) is a toxic metal frequently used in illegal and artisanal extraction of gold and silver which makes it a cause of Environmental Poisoning. Since biosorption of other heavy metals has been reported for several Lysinibacillus sphaericus strains, this study investigates Hg removal. Three L. sphaericus strains previously reported as metal tolerant (CBAM5, Ot4b31, and III(3)7) were assessed with mercury chloride (HgCl2). Bacteria were characterized by scanning electron microscopy coupled with energy dispersive spectroscopy (EDS-SEM). Sorption was evaluated in live and dead bacterial biomass by free and immobilized cells assays. Hg quantification was achieved through spectrophotometry at 508 nm by reaction of Hg supernatants with dithizone prepared in Triton X-114 and by graphite furnace atomic absorption spectroscopy (GF-AAS). Bacteria grew up to 60 ppm of HgCl2. Non-immobilized dead cell mixture of strains III(3)7 and Ot4b31 showed a maximum sorption efficiency of 28.4 µg Hg/mg bacteria during the first 5 min of contact with HgCl2, removing over 95% of Hg. This process was escalated in a semi-batch bubbling fluidized bed reactor (BFB) using rice husk as the immobilization matrix leading to a similar level of efficiency. EDS-SEM analysis showed that all strains can adsorb Hg as particles of nanometric scale that can be related to the presence of S-layer metal binding proteins as shown in previous studies. These results suggest that L. sphaericus could be used as a novel biological method of mercury removal from polluted wastewater.

  • High Efficiency Mercury Sorption by Dead Biomass of Lysinibacillus sphaericus—New Insights into the Treatment of Contaminated Water
    MDPI AG, 2019
    Co-Authors: David J. Vega-páez, Ricardo E. Rivas, Jenny Dussán-garzón
    Abstract:

    Mercury (Hg) is a toxic metal frequently used in illegal and artisanal extraction of gold and silver which makes it a cause of Environmental Poisoning. Since biosorption of other heavy metals has been reported for several Lysinibacillus sphaericus strains, this study investigates Hg removal. Three L. sphaericus strains previously reported as metal tolerant (CBAM5, Ot4b31, and III(3)7) were assessed with mercury chloride (HgCl2). Bacteria were characterized by scanning electron microscopy coupled with energy dispersive spectroscopy (EDS-SEM). Sorption was evaluated in live and dead bacterial biomass by free and immobilized cells assays. Hg quantification was achieved through spectrophotometry at 508 nm by reaction of Hg supernatants with dithizone prepared in Triton X-114 and by graphite furnace atomic absorption spectroscopy (GF-AAS). Bacteria grew up to 60 ppm of HgCl2. Non-immobilized dead cell mixture of strains III(3)7 and Ot4b31 showed a maximum sorption efficiency of 28.4 µg Hg/mg bacteria during the first 5 min of contact with HgCl2, removing over 95% of Hg. This process was escalated in a semi-batch bubbling fluidized bed reactor (BFB) using rice husk as the immobilization matrix leading to a similar level of efficiency. EDS-SEM analysis showed that all strains can adsorb Hg as particles of nanometric scale that can be related to the presence of S-layer metal binding proteins as shown in previous studies. These results suggest that L. sphaericus could be used as a novel biological method of mercury removal from polluted wastewater

N J Langford - One of the best experts on this subject based on the ideXlab platform.

  • episodes of Environmental Poisoning worldwide
    Occupational and Environmental Medicine, 2002
    Co-Authors: N J Langford, R E Ferner
    Abstract:

    The environment is composed of chemical substances, many of which are poisonous if present in large amounts, and some of which are poisonous even in small quantities. Within the industrialised world, specific concentrations of highly dangerous chemicals may be localised to a certain area, vastly increasing the risk to the local environment. Although highly regulated by legislation such as the Control of Major Accident Hazards Regulations 1999 (COMAH), and agencies such as the Health and Safety Executive (HSE) and the Environment Agency (in England and Wales), or the Scottish Environment Protection Agency (SEPA) (in Scotland), industry has been a common source of Environmental contamination. Additionally, as we discuss below, manufacturing of chemicals is not the only industrial process that places the environment at risk. Environmental Poisoning can also result from the transport, storage, and secondary uses of the primary product. Small scale releases of toxic chemical substances are common within the industrialised world.1 Their impact is usually limited by effective statutory controls and efficient emergency services, but the combination of system failures can lead to disaster. In limiting the impact of such chemical releases, effective communication is required not only between the operator and emergency services but also from the emergency services to the public. Without such communication, panic may ensue, leading to emergency and hospital services being overwhelmed and prevented from effectively pursuing their roles. The most serious events usually have an immediate impact. Probably the best known example of this was Bhopal, where 2500 people died. However, chemical disasters can also occur where the release of toxins or contamination of products is insidious. This complicates both the detection of the cause of the Poisoning and also the management of the environment and those poisoned. At the extreme, a low level continuing release of products can result in …