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Ben Koopman - One of the best experts on this subject based on the ideXlab platform.

  • Selective assay for heavy Metal Toxicity using a fluorogenic substrate
    Environmental Toxicology and Chemistry, 1996
    Co-Authors: Keumhee Jung, Gabriel Bitton, Ben Koopman
    Abstract:

    Chromogenic substrates have been generally used in enzymatic assays for the specific determination of heavy Metal Toxicity. A Toxicity assay based on the specific inhibition of β-galactosidase by heavy Metals and using a fluorogenic substrate was evaluated for its sensitivity to heavy Metals and organic toxicants. The Toxicity assay, FluoroMetPLATE, was specific for heavy Metals and was more sensitive than the widely used Microtox assay. Except for lead, our assay displayed sensitivity similar to that of the 48-h acute Ceriodaphnia dubia assay. Monitoring of industrial samples showed that the FluoroMetPLATE assay gave similar results as the daphnid Toxicity assay for 22 of 29 samples. For the remaining samples, for which there was no agreement between the two tests, it was found that the Toxicity was mostly due to organic toxicants, confirming the specificity of FluoroMetPLATE for heavy Metal Toxicity.

  • A direct solid-phase assay specific for heavy Metal Toxicity. I. methodology
    The Journal of Soil Science, 1996
    Co-Authors: Gabriel Bitton, Jean-louis Morel, Elisabeth Garland, In-chul Kong, Ben Koopman
    Abstract:

    We have developed a direct Toxicity assay for soils, sediments and sludges that is specific for heavy-Metal Toxicity. In the assay, a β-galactosidase-producingstrain of Escherichia coll is mixed with the solids sample together with a small volume (1.0 ml/0.5 to 1.0 g of solids) of eluent Extraction of Metals from the solids sample is not required. Controls run with the assay eliminate interference due to indigenous β-ga-lactosidase activity or interaction between the solid matrix and the chromaphore. Use of 0.1 M sodium nitrate as eluent was found to yield somewhat higher sensitivity to heavy Metals in solid-phase samples than MilliQ water. Application of the assay to a diverse array of soils, sludges, and sediments indicated that samples from industrial sites were generally more toxic than those from residential or commercial sites. Heavy-Metal Toxicity was correlated with the copper and zinc content of solids samples, but Toxicity varied considerably at the lower range of Metal contents. The proposed solid-phase assay should prove useful as a screening test for heavy-Metal Toxicity in soils, sediments, and sludges. It can also help distinguish between heavy Metals and organic chemicals as the cause of Toxicity in solid-phase samples.

  • A direct solid-phase assay specific for heavy Metal Toxicity. I. methodology
    The Journal of Soil Science, 1996
    Co-Authors: Gabriel Bitton, Jean-louis Morel, Elisabeth Garland, In-chul Kong, Ben Koopman
    Abstract:

    We have developed a direct Toxicity assay for soils, sediments and sludges that is specific for heavy-Metal Toxicity. In the assay, a β-galactosidase-producingstrain of Escherichia coll is mixed with the solids sample together with a small volume (1.0 ml/0.5 to 1.0 g of solids) of eluent Extraction of Metals from the solids sample is not required. Controls run with the assay eliminate interference due to indigenous β-ga-lactosidase activity or interaction between the solid matrix and the chromaphore. Use of 0.1 M sodium nitrate as eluent was found to yield somewhat higher sensitivity to heavy Metals in solid-phase samples than MilliQ water. Application of the assay to a diverse array of soils, sludges, and sediments indicated that samples from industrial sites were generally more toxic than those from residential or commercial sites. Heavy-Metal Toxicity was correlated with the copper and zinc content of solids samples, but Toxicity varied considerably at the lower range of Metal contents. The proposed solid-phase assay should prove useful as a screening test for heavy-Metal Toxicity in soils, sediments, and sludges. It can also help distinguish between heavy Metals and organic chemicals as the cause of Toxicity in solid-phase samples.

  • A direct solid‐phase assay specific for heavy Metal Toxicity. I. methodology
    Journal of Soil Contamination, 1996
    Co-Authors: Gabriel Bitton, Jean-louis Morel, In-chul Kong, Elizabeth Garland, Ben Koopman
    Abstract:

    We have developed a direct Toxicity assay for soils, sediments and sludges that is specific for heavy‐Metal Toxicity. In the assay, a β‐galactosidase‐producingstrain of Escherichia coll is mixed with the solids sample together with a small volume (1.0 ml/0.5 to 1.0 g of solids) of eluent Extraction of Metals from the solids sample is not required. Controls run with the assay eliminate interference due to indigenous β‐ga‐lactosidase activity or interaction between the solid matrix and the chromaphore. Use of 0.1 M sodium nitrate as eluent was found to yield somewhat higher sensitivity to heavy Metals in solid‐phase samples than MilliQ water. Application of the assay to a diverse array of soils, sludges, and sediments indicated that samples from industrial sites were generally more toxic than those from residential or commercial sites. Heavy‐Metal Toxicity was correlated with the copper and zinc content of solids samples, but Toxicity varied considerably at the lower range of Metal contents. The proposed so...

  • MetPADTM : a bioassay for rapid assessment of heavy Metal Toxicity in wastewater
    Water Environment Research, 1992
    Co-Authors: Gabriel Bitton, Ben Koopman, Orna Agami
    Abstract:

    MetPAD TM , a bioassay for the specific determination of heavy Metal Toxicity, was evaluated for Toxicity assessment of industrial effluents. It was shown that MetPAD does not respond to organic toxicants, but is sensitive to heavy Metals. Six of nine industrial effluents were shown to be toxic using MetPAD. Chemical analyses of the industrial effluents confirmed the presence of heavy Metals. If run concurrently with another test for general Toxicity test (for example, Microtox TM ), MetPAD can be a suitable complimentary assay for the specific determination of heavy Metal Toxicity

Gabriel Bitton - One of the best experts on this subject based on the ideXlab platform.

  • A direct solid-phase assay specific for heavy-Metal Toxicity. II. Assessment of heavy-Metal immobilization in soils and bioavailability to plants
    The Journal of Soil Science, 1996
    Co-Authors: Ali Boularbah, Gabriel Bitton, Jean-louis Morel, Michel Mench
    Abstract:

    We have used the solid-phase MetPLA TE, an enzyme assay that is specific for heavy-Metal Toxicity, to investigate Metal Toxicity of soils that have been amended with urban wastewater sludges or contaminated with dry deposition from Metal-plating industries. We have shown that soil Toxicity, using MetPLA TE, ranged from 21 to 72.5% inhibition of enzyme activity. Evin soil, which displayed the highest Toxicity, also had the highest concentrations of Pb and Zn. Metal uptake studies with ryegrass grown on Evin soil, showed Zn, Cd, and Pb accumulation in the plant that exceeds the standard levels reported for grasses Solid-phase MetPLA TE was also used as a tool to study the reduction of heavy-Metal Toxicity following soil amendments to immobilize Metals in soil and thus reduce their Toxicity. It was found that the addition of 1% hydrated manganese oxide significantly reduced dissolved Metals in soil, their accumulation by ryegrass, and soil Toxicity as shown by MetPLA TE.

  • A direct solid‐phase assay specific for heavy‐Metal Toxicity. II. Assessment of heavy‐Metal immobilization in soils and bioavailability to plants
    Journal of Soil Contamination, 1996
    Co-Authors: Ali Boularbah, Gabriel Bitton, Jean-louis Morel, Michel Mench
    Abstract:

    We have used the solid‐phase MetPLA TE, an enzyme assay that is specific for heavy‐Metal Toxicity, to investigate Metal Toxicity of soils that have been amended with urban wastewater sludges or contaminated with dry deposition from Metal‐plating industries. We have shown that soil Toxicity, using MetPLA TE, ranged from 21 to 72.5% inhibition of enzyme activity. Evin soil, which displayed the highest Toxicity, also had the highest concentrations of Pb and Zn. Metal uptake studies with ryegrass grown on Evin soil, showed Zn, Cd, and Pb accumulation in the plant that exceeds the standard levels reported for grasses Solid‐phase MetPLA TE was also used as a tool to study the reduction of heavy‐Metal Toxicity following soil amendments to immobilize Metals in soil and thus reduce their Toxicity. It was found that the addition of 1% hydrated manganese oxide significantly reduced dissolved Metals in soil, their accumulation by ryegrass, and soil Toxicity as shown by MetPLA TE.

  • Selective assay for heavy Metal Toxicity using a fluorogenic substrate
    Environmental Toxicology and Chemistry, 1996
    Co-Authors: Keumhee Jung, Gabriel Bitton, Ben Koopman
    Abstract:

    Chromogenic substrates have been generally used in enzymatic assays for the specific determination of heavy Metal Toxicity. A Toxicity assay based on the specific inhibition of β-galactosidase by heavy Metals and using a fluorogenic substrate was evaluated for its sensitivity to heavy Metals and organic toxicants. The Toxicity assay, FluoroMetPLATE, was specific for heavy Metals and was more sensitive than the widely used Microtox assay. Except for lead, our assay displayed sensitivity similar to that of the 48-h acute Ceriodaphnia dubia assay. Monitoring of industrial samples showed that the FluoroMetPLATE assay gave similar results as the daphnid Toxicity assay for 22 of 29 samples. For the remaining samples, for which there was no agreement between the two tests, it was found that the Toxicity was mostly due to organic toxicants, confirming the specificity of FluoroMetPLATE for heavy Metal Toxicity.

  • A direct solid-phase assay specific for heavy Metal Toxicity. I. methodology
    The Journal of Soil Science, 1996
    Co-Authors: Gabriel Bitton, Jean-louis Morel, Elisabeth Garland, In-chul Kong, Ben Koopman
    Abstract:

    We have developed a direct Toxicity assay for soils, sediments and sludges that is specific for heavy-Metal Toxicity. In the assay, a β-galactosidase-producingstrain of Escherichia coll is mixed with the solids sample together with a small volume (1.0 ml/0.5 to 1.0 g of solids) of eluent Extraction of Metals from the solids sample is not required. Controls run with the assay eliminate interference due to indigenous β-ga-lactosidase activity or interaction between the solid matrix and the chromaphore. Use of 0.1 M sodium nitrate as eluent was found to yield somewhat higher sensitivity to heavy Metals in solid-phase samples than MilliQ water. Application of the assay to a diverse array of soils, sludges, and sediments indicated that samples from industrial sites were generally more toxic than those from residential or commercial sites. Heavy-Metal Toxicity was correlated with the copper and zinc content of solids samples, but Toxicity varied considerably at the lower range of Metal contents. The proposed solid-phase assay should prove useful as a screening test for heavy-Metal Toxicity in soils, sediments, and sludges. It can also help distinguish between heavy Metals and organic chemicals as the cause of Toxicity in solid-phase samples.

  • A direct solid-phase assay specific for heavy Metal Toxicity. I. methodology
    The Journal of Soil Science, 1996
    Co-Authors: Gabriel Bitton, Jean-louis Morel, Elisabeth Garland, In-chul Kong, Ben Koopman
    Abstract:

    We have developed a direct Toxicity assay for soils, sediments and sludges that is specific for heavy-Metal Toxicity. In the assay, a β-galactosidase-producingstrain of Escherichia coll is mixed with the solids sample together with a small volume (1.0 ml/0.5 to 1.0 g of solids) of eluent Extraction of Metals from the solids sample is not required. Controls run with the assay eliminate interference due to indigenous β-ga-lactosidase activity or interaction between the solid matrix and the chromaphore. Use of 0.1 M sodium nitrate as eluent was found to yield somewhat higher sensitivity to heavy Metals in solid-phase samples than MilliQ water. Application of the assay to a diverse array of soils, sludges, and sediments indicated that samples from industrial sites were generally more toxic than those from residential or commercial sites. Heavy-Metal Toxicity was correlated with the copper and zinc content of solids samples, but Toxicity varied considerably at the lower range of Metal contents. The proposed solid-phase assay should prove useful as a screening test for heavy-Metal Toxicity in soils, sediments, and sludges. It can also help distinguish between heavy Metals and organic chemicals as the cause of Toxicity in solid-phase samples.

Michel Mench - One of the best experts on this subject based on the ideXlab platform.

  • A direct solid-phase assay specific for heavy-Metal Toxicity. II. Assessment of heavy-Metal immobilization in soils and bioavailability to plants
    The Journal of Soil Science, 1996
    Co-Authors: Ali Boularbah, Gabriel Bitton, Jean-louis Morel, Michel Mench
    Abstract:

    We have used the solid-phase MetPLA TE, an enzyme assay that is specific for heavy-Metal Toxicity, to investigate Metal Toxicity of soils that have been amended with urban wastewater sludges or contaminated with dry deposition from Metal-plating industries. We have shown that soil Toxicity, using MetPLA TE, ranged from 21 to 72.5% inhibition of enzyme activity. Evin soil, which displayed the highest Toxicity, also had the highest concentrations of Pb and Zn. Metal uptake studies with ryegrass grown on Evin soil, showed Zn, Cd, and Pb accumulation in the plant that exceeds the standard levels reported for grasses Solid-phase MetPLA TE was also used as a tool to study the reduction of heavy-Metal Toxicity following soil amendments to immobilize Metals in soil and thus reduce their Toxicity. It was found that the addition of 1% hydrated manganese oxide significantly reduced dissolved Metals in soil, their accumulation by ryegrass, and soil Toxicity as shown by MetPLA TE.

  • A direct solid‐phase assay specific for heavy‐Metal Toxicity. II. Assessment of heavy‐Metal immobilization in soils and bioavailability to plants
    Journal of Soil Contamination, 1996
    Co-Authors: Ali Boularbah, Gabriel Bitton, Jean-louis Morel, Michel Mench
    Abstract:

    We have used the solid‐phase MetPLA TE, an enzyme assay that is specific for heavy‐Metal Toxicity, to investigate Metal Toxicity of soils that have been amended with urban wastewater sludges or contaminated with dry deposition from Metal‐plating industries. We have shown that soil Toxicity, using MetPLA TE, ranged from 21 to 72.5% inhibition of enzyme activity. Evin soil, which displayed the highest Toxicity, also had the highest concentrations of Pb and Zn. Metal uptake studies with ryegrass grown on Evin soil, showed Zn, Cd, and Pb accumulation in the plant that exceeds the standard levels reported for grasses Solid‐phase MetPLA TE was also used as a tool to study the reduction of heavy‐Metal Toxicity following soil amendments to immobilize Metals in soil and thus reduce their Toxicity. It was found that the addition of 1% hydrated manganese oxide significantly reduced dissolved Metals in soil, their accumulation by ryegrass, and soil Toxicity as shown by MetPLA TE.

Jean-louis Morel - One of the best experts on this subject based on the ideXlab platform.

  • A direct solid-phase assay specific for heavy-Metal Toxicity. II. Assessment of heavy-Metal immobilization in soils and bioavailability to plants
    The Journal of Soil Science, 1996
    Co-Authors: Ali Boularbah, Gabriel Bitton, Jean-louis Morel, Michel Mench
    Abstract:

    We have used the solid-phase MetPLA TE, an enzyme assay that is specific for heavy-Metal Toxicity, to investigate Metal Toxicity of soils that have been amended with urban wastewater sludges or contaminated with dry deposition from Metal-plating industries. We have shown that soil Toxicity, using MetPLA TE, ranged from 21 to 72.5% inhibition of enzyme activity. Evin soil, which displayed the highest Toxicity, also had the highest concentrations of Pb and Zn. Metal uptake studies with ryegrass grown on Evin soil, showed Zn, Cd, and Pb accumulation in the plant that exceeds the standard levels reported for grasses Solid-phase MetPLA TE was also used as a tool to study the reduction of heavy-Metal Toxicity following soil amendments to immobilize Metals in soil and thus reduce their Toxicity. It was found that the addition of 1% hydrated manganese oxide significantly reduced dissolved Metals in soil, their accumulation by ryegrass, and soil Toxicity as shown by MetPLA TE.

  • A direct solid‐phase assay specific for heavy‐Metal Toxicity. II. Assessment of heavy‐Metal immobilization in soils and bioavailability to plants
    Journal of Soil Contamination, 1996
    Co-Authors: Ali Boularbah, Gabriel Bitton, Jean-louis Morel, Michel Mench
    Abstract:

    We have used the solid‐phase MetPLA TE, an enzyme assay that is specific for heavy‐Metal Toxicity, to investigate Metal Toxicity of soils that have been amended with urban wastewater sludges or contaminated with dry deposition from Metal‐plating industries. We have shown that soil Toxicity, using MetPLA TE, ranged from 21 to 72.5% inhibition of enzyme activity. Evin soil, which displayed the highest Toxicity, also had the highest concentrations of Pb and Zn. Metal uptake studies with ryegrass grown on Evin soil, showed Zn, Cd, and Pb accumulation in the plant that exceeds the standard levels reported for grasses Solid‐phase MetPLA TE was also used as a tool to study the reduction of heavy‐Metal Toxicity following soil amendments to immobilize Metals in soil and thus reduce their Toxicity. It was found that the addition of 1% hydrated manganese oxide significantly reduced dissolved Metals in soil, their accumulation by ryegrass, and soil Toxicity as shown by MetPLA TE.

  • A direct solid-phase assay specific for heavy Metal Toxicity. I. methodology
    The Journal of Soil Science, 1996
    Co-Authors: Gabriel Bitton, Jean-louis Morel, Elisabeth Garland, In-chul Kong, Ben Koopman
    Abstract:

    We have developed a direct Toxicity assay for soils, sediments and sludges that is specific for heavy-Metal Toxicity. In the assay, a β-galactosidase-producingstrain of Escherichia coll is mixed with the solids sample together with a small volume (1.0 ml/0.5 to 1.0 g of solids) of eluent Extraction of Metals from the solids sample is not required. Controls run with the assay eliminate interference due to indigenous β-ga-lactosidase activity or interaction between the solid matrix and the chromaphore. Use of 0.1 M sodium nitrate as eluent was found to yield somewhat higher sensitivity to heavy Metals in solid-phase samples than MilliQ water. Application of the assay to a diverse array of soils, sludges, and sediments indicated that samples from industrial sites were generally more toxic than those from residential or commercial sites. Heavy-Metal Toxicity was correlated with the copper and zinc content of solids samples, but Toxicity varied considerably at the lower range of Metal contents. The proposed solid-phase assay should prove useful as a screening test for heavy-Metal Toxicity in soils, sediments, and sludges. It can also help distinguish between heavy Metals and organic chemicals as the cause of Toxicity in solid-phase samples.

  • A direct solid-phase assay specific for heavy Metal Toxicity. I. methodology
    The Journal of Soil Science, 1996
    Co-Authors: Gabriel Bitton, Jean-louis Morel, Elisabeth Garland, In-chul Kong, Ben Koopman
    Abstract:

    We have developed a direct Toxicity assay for soils, sediments and sludges that is specific for heavy-Metal Toxicity. In the assay, a β-galactosidase-producingstrain of Escherichia coll is mixed with the solids sample together with a small volume (1.0 ml/0.5 to 1.0 g of solids) of eluent Extraction of Metals from the solids sample is not required. Controls run with the assay eliminate interference due to indigenous β-ga-lactosidase activity or interaction between the solid matrix and the chromaphore. Use of 0.1 M sodium nitrate as eluent was found to yield somewhat higher sensitivity to heavy Metals in solid-phase samples than MilliQ water. Application of the assay to a diverse array of soils, sludges, and sediments indicated that samples from industrial sites were generally more toxic than those from residential or commercial sites. Heavy-Metal Toxicity was correlated with the copper and zinc content of solids samples, but Toxicity varied considerably at the lower range of Metal contents. The proposed solid-phase assay should prove useful as a screening test for heavy-Metal Toxicity in soils, sediments, and sludges. It can also help distinguish between heavy Metals and organic chemicals as the cause of Toxicity in solid-phase samples.

  • A direct solid‐phase assay specific for heavy Metal Toxicity. I. methodology
    Journal of Soil Contamination, 1996
    Co-Authors: Gabriel Bitton, Jean-louis Morel, In-chul Kong, Elizabeth Garland, Ben Koopman
    Abstract:

    We have developed a direct Toxicity assay for soils, sediments and sludges that is specific for heavy‐Metal Toxicity. In the assay, a β‐galactosidase‐producingstrain of Escherichia coll is mixed with the solids sample together with a small volume (1.0 ml/0.5 to 1.0 g of solids) of eluent Extraction of Metals from the solids sample is not required. Controls run with the assay eliminate interference due to indigenous β‐ga‐lactosidase activity or interaction between the solid matrix and the chromaphore. Use of 0.1 M sodium nitrate as eluent was found to yield somewhat higher sensitivity to heavy Metals in solid‐phase samples than MilliQ water. Application of the assay to a diverse array of soils, sludges, and sediments indicated that samples from industrial sites were generally more toxic than those from residential or commercial sites. Heavy‐Metal Toxicity was correlated with the copper and zinc content of solids samples, but Toxicity varied considerably at the lower range of Metal contents. The proposed so...

Ali Boularbah - One of the best experts on this subject based on the ideXlab platform.

  • A direct solid-phase assay specific for heavy-Metal Toxicity. II. Assessment of heavy-Metal immobilization in soils and bioavailability to plants
    The Journal of Soil Science, 1996
    Co-Authors: Ali Boularbah, Gabriel Bitton, Jean-louis Morel, Michel Mench
    Abstract:

    We have used the solid-phase MetPLA TE, an enzyme assay that is specific for heavy-Metal Toxicity, to investigate Metal Toxicity of soils that have been amended with urban wastewater sludges or contaminated with dry deposition from Metal-plating industries. We have shown that soil Toxicity, using MetPLA TE, ranged from 21 to 72.5% inhibition of enzyme activity. Evin soil, which displayed the highest Toxicity, also had the highest concentrations of Pb and Zn. Metal uptake studies with ryegrass grown on Evin soil, showed Zn, Cd, and Pb accumulation in the plant that exceeds the standard levels reported for grasses Solid-phase MetPLA TE was also used as a tool to study the reduction of heavy-Metal Toxicity following soil amendments to immobilize Metals in soil and thus reduce their Toxicity. It was found that the addition of 1% hydrated manganese oxide significantly reduced dissolved Metals in soil, their accumulation by ryegrass, and soil Toxicity as shown by MetPLA TE.

  • A direct solid‐phase assay specific for heavy‐Metal Toxicity. II. Assessment of heavy‐Metal immobilization in soils and bioavailability to plants
    Journal of Soil Contamination, 1996
    Co-Authors: Ali Boularbah, Gabriel Bitton, Jean-louis Morel, Michel Mench
    Abstract:

    We have used the solid‐phase MetPLA TE, an enzyme assay that is specific for heavy‐Metal Toxicity, to investigate Metal Toxicity of soils that have been amended with urban wastewater sludges or contaminated with dry deposition from Metal‐plating industries. We have shown that soil Toxicity, using MetPLA TE, ranged from 21 to 72.5% inhibition of enzyme activity. Evin soil, which displayed the highest Toxicity, also had the highest concentrations of Pb and Zn. Metal uptake studies with ryegrass grown on Evin soil, showed Zn, Cd, and Pb accumulation in the plant that exceeds the standard levels reported for grasses Solid‐phase MetPLA TE was also used as a tool to study the reduction of heavy‐Metal Toxicity following soil amendments to immobilize Metals in soil and thus reduce their Toxicity. It was found that the addition of 1% hydrated manganese oxide significantly reduced dissolved Metals in soil, their accumulation by ryegrass, and soil Toxicity as shown by MetPLA TE.