Influence of pH, temperature and sediment type on the toxicity, accumulation and degradation of parathion in aquatic systems

Lydy, Michael J.; Lohner, Timothy W.; Fisher, Susan W.

doi:10.1016/0166-445x(90)90010-m

Cited by 49 publications

(41 citation statements)

References 20 publications

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“…for several insecticides, which was accounted for by the enhanced transformation to polar metabolites, these being more easily depurated. 22,25,26) The contribution of metabolism to a reduced BCF was also proposed for the water exposure of Pteronarcys californica (stonefly) to DDT. 101) A temperature effect on BCF was quantitatively confirmed by the detailed kinetic analysis of the exposure of Chironomus dilutus to chlorpyrifos and two pyrethroids at 13 and 23°C, showing a higher contribution of k M and k D than k U at 23°C.…”

Section: =093)mentioning

confidence: 99%

“…The spectrophotometric assay of the CaE activity is generally conducted by using α-and β-NA as substrates. Its specific activity (nmol/min/mg protein) seems to be lower in black flies , 57,58) the caddisfly (92), 56) and midges (20)(21)(22)(23)(24)(25)(26)(27)(28)(29)(30)(31)(32)(33)(34)(35)(36), 47,59) as compared with D. magna (220) 60) and Hyalella curvispina (amphipod) (101). 61) Although the number of tested substrates is limited, the CaE activity decreased as follows: black fly>caddisfly≥mayfly>damselfly.…”

Section: Esterasesmentioning

confidence: 99%

“…21) Chironomus spp. metabolize OP pesticides [25][26][27][28][29] via either oxidative desulfurization to the respective oxon or hydrolysis to the corresponding phenols. The oxidative dealkylation 23,32,33) at N, O, and Sn atoms and enzymatic hydrolysis [22][23][24] of amides and car- Exp.…”

Section: Metabolism 1in Vivo and In Vitro Metabolism Of Pesticidesmentioning

confidence: 99%

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Metabolism, bioaccumulation, and toxicity of pesticides in aquatic insect larvae

Katagi

Tanaka

2016

Journal of Pesticide Science

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Aquatic insects having a high diversity are good biotic indicators for freshwater quality. Their larvae living in freshwater are sensitive to pesticides, and its impacts has been examined not only through laboratory toxicity studies using water and sediment exposure but also through higher-tier micro-/mesocosm studies and field monitoring. Many sophisticated statistical methods have been applied to assess the impacts of pesticides at levels from species to community, but their body burden has been studied much less, especially in relation to toxicity. We review the uptake, metabolism with relevant detoxifying enzymes, and depuration of pesticides in aquatic insect larvae, which determine their body burden and help to understand the toxicity profiles specific to each chemical class. We also discuss experimental conditions, environmental factors, and species sensitivity in relation to the bioconcentration/-accumulation and toxicity of pesticides.

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Section: =093)mentioning

confidence: 99%

Section: Esterasesmentioning

confidence: 99%

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Metabolism, bioaccumulation, and toxicity of pesticides in aquatic insect larvae

Katagi

Tanaka

2016

Journal of Pesticide Science

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“…Several researchers have suggested that normalization to organic carbon will essentially eliminate the variability in bioavailability of sediment-associated nonpolar organic compounds [ 100,1011, and a comparison of sediment uptake RCs has shown a relationship with sediment carbon [37,97]. However, simple carbon normalization does not account for the effects of different carbon types on partitioning [lo21 or the effects of aging on bioavailability [37,1031. Environmental factors such as pH can alter the characteristics of the chemical through ionization of functional groups or hydrolysis of ester and amide linkages, reducing bioavailability and, therefore, the uptake rate [50,104,105]. Temperature generally alters toxicokinetics by changing organism physiology.…”

Section: Environmental and Physiological Factorsmentioning

confidence: 99%

Toxicokinetics in aquatic systems: Model comparisons and use in hazard assessment

Landrum

Lydy

Lee

1992

Enviro Toxic and Chemistry

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346

247

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-Toxicokinetic models are not constrained by assumptions of equilibrium as are thermodynamic (equilibrium-partitioning) models and are more accurate predictors of toxicant accumulation for non-steady-state exposures and multiple uptake routes. Toxicokinetic models -compartmentbased models, physiological-based models, and energetics-based models-are reviewed and the different mathematical formalisms compared. Additionally, the residue-based toxicity approach is reviewed. Coupling toxicokinetic models with tissue concentrations at which toxicity occurs offers a direct link between exposure and hazard. Basing hazard on tissue rather than environmental concentrations avoids the errors associated with accommodating multiple sources, pulsed exposures, and non-steady-state accumulation. Keywords-Kinetic models Bioaccumulation Tissue residue effects Sediment contaminationHazard assessment INTRODUCTlONAssessment and prediction of toxicant effects on aquatic organisms require evaluation of the extent of organism exposure. Exposure assessment establishes the relationship between environmental toxicant concentrations and organism accumulation while accounting for environmental and biological factors that modify exposure. If the relationships between the amount of toxicant accumulated and the resulting effects are known, then the hazard for a particular exposure regime can be established.Aquatic exposure assessments and predictions have employed mainly steady-state and equilibriumpartitioning models. Early efforts, using simple kinetic models, were designed to provide estimates of steady-state accumulation from water exposures [1,2]. These steady-state estimates were then utilized in hazard assessments based on thermodynamic limits (chemical equilibrium). Such models have been employed with good success for evaluation of general conditions, describing toxicant distribution among ecosystem components and *To whom correspondence may be addressed.identifying components dominating toxicant mass balance. This approach has been best refined using the fugacity concept and applied to describe the importance of sediment as a toxicant source [3] and toxicant distributions within ecosystems [4,5].Although there is a continued focus on equilibrium-partitioning models within regulatory agencies, it is clear that the environment is complex and variable. Therefore, to obtain more accurate predictions and assessments, kinetic models are needed to predict non-steady-state, nonequilibrium accumulation from temporally and spatially varying exposures when the simplifying assumptions of the equilibrium-partitioning models are inappropriate, for example, when multiple sources contribute significantly to accumulation.Kinetic models have been used successfully in pharmacology for decades. Such models permit prediction of the onset of drug action and allow the monitoring of drug clearance and termination of effects. Further, these kinetic models describe changes in tissue concentrations resulting from absorption, distribution, metabolism, a...

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“…Based on literature data, alkaline hydrolysis appears very favorable for this type of transformation. [19][20][21][22] The experimental portion was especially based on the kinetics study of the hydrolysis of MP by decontamination with aqueous solutions containing 2-aminoethanol (EA) at different concentrations and under different values of pH and temperature, completing our first optimization work. 23) It is easy to monitor the kinetics of hydrolysis by UV-Visible spectrometry (UV-Vis).…”

Section: Co-genotoxic Potential In Human Hepatoma Hepg2 Cells May Be mentioning

confidence: 99%

Hydrolytic decontamination of methyl parathion in the presence of 2-aminoethanol: Kinetics study

Doumandji¹,

Moussiden

Ihdene³

et al. 2018

Journal of Pesticide Science

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Methyl parathion (MP) decontamination by hydrolysis in aqueous solutions containing 2-aminoethanol (EA) was investigated using the UV-Visible and GC/MS techniques. The kinetics of the hydrolysis reaction was studied at pH values of 4, 7, and 9 in water at 75, 85, and 95°C, respectively. At various EA concentrations 60, 100, and 200 mg/L MP degradation followed pseudofirst order kinetics and was found to be strongly pH and temperature dependent. The rate of MP degradation accelerated significantly as pH increased. The conversion reached 93.5% after 90 min of hydrolysis at a pH of 9, as compared to 69.9% and 49.8% at pH values of 7 and 4, respectively. The MP degradation byproducts removed from aqueous solutions by solid phase microextraction (SPME) were identified. The main intermediate products were p-nitrophenol and O,O-dimethyl phosphorothioate. This study concludes that hydrolysis in the presence of EA is an effective process for decontaminating solutions containing MP.

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Influence of pH, temperature and sediment type on the toxicity, accumulation and degradation of parathion in aquatic systems

Cited by 49 publications

References 20 publications

Metabolism, bioaccumulation, and toxicity of pesticides in aquatic insect larvae

Metabolism, bioaccumulation, and toxicity of pesticides in aquatic insect larvae

Toxicokinetics in aquatic systems: Model comparisons and use in hazard assessment

Hydrolytic decontamination of methyl parathion in the presence of 2-aminoethanol: Kinetics study

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