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Bandeira FO, Lodi MR, Graciani TS, Oroski S, Mattias JL, Cardoso EJBN, Alves PRL. The use of sewage sludge as remediation for imidacloprid toxicity in soils. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2023; 30:20159-20167. [PMID: 36251199 DOI: 10.1007/s11356-022-23584-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/14/2022] [Accepted: 10/08/2022] [Indexed: 06/16/2023]
Abstract
This study investigated the influence of the sewage sludge (SS) soil amendment on the chronic toxicity of imidacloprid (through the seed dressing formulation MUCH 600 FS®-600 g active ingredient L-1) to collembolans Folsomia candida. Individuals 10-12 days old were exposed to two contrasting tropical soils (Oxisol and Entisol) amended with SS doses (0, 20, 40, 80, 160, and 320 g SS kg-1 soil; the SS doses have low intrinsic toxicity, which was checked before its application) in a full factorial combination with five imidacloprid concentrations (varying from 0.25 to 4 mg kg-1 in Oxisol and 0.03-0.5 mg kg-1 in Entisol) plus a control. None of the SS doses (without imidacloprid) in both soils reduced the number of generated juvenile collembolans. The imidacloprid concentrations reducing the collembolan reproduction in 50% (EC50) in Oxisol and Entisol without SS were 0.49 and 0.08 mg kg-1, respectively. However, the EC50 values generally increased with increasing SS doses in soils, varying from 1.03 to 1.41 in Oxisol and 0.07 to 0.21 in Entisol. The SS-amended soils showed 2.1- to 2.9-fold lower imidacloprid toxicity (EC50-based) in Oxisol and 1.8- to 2.7-fold lower toxicity in Entisol. Our results suggest the most effective SS doses alleviating the imidacloprid toxicity (EC50-based) to collembolans are 20 g kg-1 in Oxisol and 80 g kg-1 in Entisol. These results indicate that the tested SS has the potential to be employed as a soil amendment agent by reducing the toxicity of imidacloprid to the reproduction of F. candida.
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Affiliation(s)
- Felipe Ogliari Bandeira
- Department of Soil Science, Santa Catarina State University, 88520-000 Lages, Av. Luis de Camões, SC, 2090, Brazil
| | - Mikael Renan Lodi
- Universidade Federal da Fronteira Sul, Av. Fernando Machado 108 E, Chapecó, SC, 89802112, Brazil
| | | | - Sabrina Oroski
- Universidade Federal da Fronteira Sul, Av. Fernando Machado 108 E, Chapecó, SC, 89802112, Brazil
| | - Jorge Luis Mattias
- Universidade Federal da Fronteira Sul, Av. Fernando Machado 108 E, Chapecó, SC, 89802112, Brazil
| | | | - Paulo Roger Lopes Alves
- Universidade Federal da Fronteira Sul, Av. Fernando Machado 108 E, Chapecó, SC, 89802112, Brazil.
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Bernardino MM, Alves PRL, de Santo FB, Niemeyer JC, Leal RMP. Ecotoxicity of imidacloprid to soil invertebrates in two tropical soils with contrasting texture. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2021; 28:27655-27665. [PMID: 33512682 DOI: 10.1007/s11356-021-12562-0] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/11/2020] [Accepted: 01/15/2021] [Indexed: 06/12/2023]
Abstract
Imidacloprid is one of the most commercialized insecticides in agriculture in the world, with a broad spectrum of action. However, little is known about the effects of commercial formulations containing this active ingredient (a.i.) on non-target organisms in tropical soils. Our objective was to assess the toxicity based on the predicted environmental concentration (PEC) of imidacloprid, in the avoidance behaviour of earthworms and collembolans as well as in the reproduction of collembolans, in two representative soils of the Brazilian Cerrado with contrasting texture (clayey Oxisol and sandy Entisol). Ecotoxicity tests were carried out according to ISO protocols to assess the avoidance behaviour of earthworms (Eisenia andrei) and avoidance and reproduction of collembolans (Folsomia candida). In the earthworm's avoidance test, more than 80% of the individuals were found in the control, in all tested concentrations, indicating a possible habitat function loss in both soils. The avoidance behaviour of collembolans was observed in both soils, being more expressive (up to 75% of escape) in Oxisol. In Entisol, only the two highest concentrations were avoided (up to 63%). There was a negative effect on the reproduction of collembolans in both soils, with a higher EC50 value (0.255 mg kg-1) in Oxisol than in Entisol (0.177 mg kg-1), demonstrating higher toxicity in the sandy soil. These differences were attributed to the contrasting texture of the studied soils, probably due to lower retention of the a.i. in the sandy soil, causing an increased bioavailability. This study demonstrated that imidacloprid can be highly toxic to soil invertebrates, even in soil concentrations lower than those expected from recommended dose, causing an impact on the edaphic organisms and, consequently, compromising its functions in the soil ecosystem.
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Affiliation(s)
- Murilo Martins Bernardino
- Postgraduate Program in Agrochemistry, Goiano Federal Institute of Education, Science and Technology, P.O Box 66, Campus Rio Verde, Rio Verde, Goiás, 75901-970, Brazil
| | - Paulo Roger Lopes Alves
- Federal University of Fronteira Sul, Av. Fernando Machado 108 E, Chapeco, SC, 89802112, Brazil
| | - Fernanda Benedet de Santo
- Postgraduate Program in Agricultural and Natural Ecosystems (PPGEAN), Federal University of Santa Catarina (UFSC), Campus of Curitibanos, Curitibanos, Santa Catarina, 89520-000, Brazil
| | - Júlia Carina Niemeyer
- Postgraduate Program in Agricultural and Natural Ecosystems (PPGEAN), Federal University of Santa Catarina (UFSC), Campus of Curitibanos, Curitibanos, Santa Catarina, 89520-000, Brazil.
| | - Rafael Marques Pereira Leal
- Postgraduate Program in Agrochemistry, Goiano Federal Institute of Education, Science and Technology, P.O Box 66, Campus Rio Verde, Rio Verde, Goiás, 75901-970, Brazil
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Li Y, Su P, Li Y, Wen K, Bi G, Cox M. Adsorption-desorption and degradation of insecticides clothianidin and thiamethoxam in agricultural soils. CHEMOSPHERE 2018; 207:708-714. [PMID: 29857203 DOI: 10.1016/j.chemosphere.2018.05.139] [Citation(s) in RCA: 47] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/23/2018] [Revised: 05/11/2018] [Accepted: 05/23/2018] [Indexed: 06/08/2023]
Abstract
Studied were the adsorption-desorption and degradation of two widely used neonicotinoid insecticides clothianidin and thiamethoxam in three different agricultural soils in the state of Mississippi. The adsorptions of both the neonicotinoids fit a linear isotherm model. In different soils at different depths with different moisture contents, the adsorption distribution coefficients of clothianidin and thiamethoxam were found to be 0.62 to 1.94 and 0.59-2.03 L kg-1, respectively. These distribution coefficients showed strong positive correlations with organic carbon content and pH of the soils. The desorptions of clothianidin and thiamethoxam also followed a linear isotherm, but were irreversible in respect to their adsorption isotherms. The desorption distribution coefficients ranged from 0.14 to 0.62 L kg-1, increased with the decrease of organic carbon content. The degradations of clothianidin and thiamethoxam in the soils were found to be slow with half-lives ranged from 90 to 280 and 65 to 170 d for clothianidin and thiamethoxam respectively. The degradation rates increased with the increase of the organic carbon content in the soils. The moisture content in the soils had a positive effect on the degradation rates. The Groundwater Ubiquity Scores calculated from the adsorption distribution coefficient, organic content, and half-life suggest that clothianidin and thiamethoxam have moderate to high potential to leach to groundwater.
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Affiliation(s)
- Yang Li
- Dept. of Civil and Environmental Engineering, Jackson State University, 1400 John R. Lynch St., Jackson, MS 39217, USA
| | - Peidong Su
- Dept. of Civil and Environmental Engineering, Jackson State University, 1400 John R. Lynch St., Jackson, MS 39217, USA
| | - Yadong Li
- Dept. of Civil and Environmental Engineering, Jackson State University, 1400 John R. Lynch St., Jackson, MS 39217, USA.
| | - Kejun Wen
- Dept. of Civil and Environmental Engineering, Jackson State University, 1400 John R. Lynch St., Jackson, MS 39217, USA
| | - Guihong Bi
- Dept. of Plant and Soil Sciences, Mississippi State University, 32 Creelman St., Mississippi State, MS 39762, USA
| | - Michael Cox
- Dept. of Plant and Soil Sciences, Mississippi State University, 32 Creelman St., Mississippi State, MS 39762, USA
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Lewis SE, Silburn DM, Kookana RS, Shaw M. Pesticide Behavior, Fate, and Effects in the Tropics: An Overview of the Current State of Knowledge. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2016; 64:3917-3924. [PMID: 27160796 DOI: 10.1021/acs.jafc.6b01320] [Citation(s) in RCA: 55] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
This special issue presents a collection of papers covering the environmental fate, effects, and risk of pesticides in tropical environments, which is expected to facilitate improved management of pesticides. Environmental monitoring programs of surface and ground waters in the tropics, including areas of high ecological value, have detected several relatively polar pesticides at concentrations that are of ecological concern. Novel monitoring techniques have the capacity to reveal the spatial and temporal extent of such risks. To best manage these pesticides, their sorption, dissipation rates, leaching, and runoff potential need to be better understood. On these aspects, important insights have been provided by several studies within this issue. Improved understanding of the environmental fate, effects, and risks through studies presented in this special issue is crucial for minimizing the nontarget impacts of pesticides on biodiversity-rich tropical regions.
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Affiliation(s)
- Stephen E Lewis
- Catchment to Reef Research Group, TropWATER, James Cook University , Townsville, QLD 4811, Australia
| | - D Mark Silburn
- Department of Natural Resources and Mines , Toowoomba, QLD 4350, Australia
- National Centre for Engineering in Agriculture, University of Southern Queensland , Toowoomba, QLD 4350, Australia
| | - Rai S Kookana
- CSIRO Land and Water/University of Adelaide , Waite Campus, Glen Osmond, SA 5064, Australia
| | - Melanie Shaw
- Department of Natural Resources and Mines , Toowoomba, QLD 4350, Australia
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Kandil MM, El-Aswad AF, Koskinen WC. Sorption-desorption of imidacloprid onto a lacustrine Egyptian soil and its clay and humic acid fractions. JOURNAL OF ENVIRONMENTAL SCIENCE AND HEALTH. PART. B, PESTICIDES, FOOD CONTAMINANTS, AND AGRICULTURAL WASTES 2015; 50:473-483. [PMID: 25996811 DOI: 10.1080/03601234.2015.1018758] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
Sorption-desorption of the insecticide imidacloprid 1-[(6-chloro-3-pyridinyl)-methyl]-N-nitro-2-imidazolidinimine onto a lacustrine sandy clay loam Egyptian soil and its clay and humic acid (HA) fractions was investigated in 24-h batch equilibrium experiments. Imidacloprid (IMDA) sorption-desorption isotherms onto the three sorbents were found to belong to a non-linear L-type and were best described by the Freundlich model. The value of the IMDA adsorption distribution coefficient, Kd(ads), varied according to its initial concentration and was ranged 40-84 for HA, 14-58 for clay and 1.85-4.15 for bulk soil. Freundlich sorption coefficient, Kf(ads), values were 63.0, 39.7 and 4.0 for HA, clay and bulk soil, respectively. The normalized soil Koc value for imidacloprid sorption was ∼800 indicating its slight mobility in soils. Nonlinear sorption isotherms were indicated by 1/n(ads) values <1 for all sorbents. Values of the hysteresis index (H) were <1, indicating the irreversibility of imidacloprid sorption process with all tested sorbents. Gibbs free energy (ΔG) values indicated a spontaneous and physicosorption process for IMDA and a more favorable sorption to HA than clay and soil. In conclusion, although the humic acid fraction showed the highest capacity and affinity for imidacloprid sorption, the clay fraction contributed to approximately 95% of soil-sorbed insecticide. Clay and humic acid fractions were found to be the major two factors controlling IMDA sorption in soils. The slight mobility of IMDA in soils and the hysteresis phenomenon associated with the irreversibility of its sorption onto, mainly, clay and organic matter of soils make its leachability unlikely to occur.
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Affiliation(s)
- Mahrous M Kandil
- a Department of Soil and Water , Faculty of Agriculture , Alexandria University , Alexandria , Egypt
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Katayama A, Bhula R, Burns GR, Carazo E, Felsot A, Hamilton D, Harris C, Kim YH, Kleter G, Koedel W, Linders J, Peijnenburg JGMW, Sabljic A, Stephenson RG, Racke DK, Rubin B, Tanaka K, Unsworth J, Wauchope RD. Bioavailability of xenobiotics in the soil environment. REVIEWS OF ENVIRONMENTAL CONTAMINATION AND TOXICOLOGY 2010; 203:1-86. [PMID: 19957116 DOI: 10.1007/978-1-4419-1352-4_1] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
It is often presumed that all chemicals in soil are available to microorganisms, plant roots, and soil fauna via dermal exposure. Subsequent bioaccumulation through the food chain may then result in exposure to higher organisms. Using the presumption of total availability, national governments reduce environmental threshold levels of regulated chemicals by increasing guideline safety margins. However, evidence shows that chemical residues in the soil environment are not always bioavailable. Hence, actual chemical exposure levels of biota are much less than concentrations present in soil would suggest. Because "bioavailability" conveys meaning that combines implications of chemical sol persistency, efficacy, and toxicity, insights on the magnitude of a chemicals soil bioavailability is valuable. however, soil bioavailability of chemicals is a complex topic, and is affected by chemical properties, soil properties, species exposed, climate, and interaction processes. In this review, the state-of-art scientific basis for bioavailability is addressed. Key points covered include: definition, factors affecting bioavailability, equations governing key transport and distributive kinetics, and primary methods for estimating bioavailability. Primary transport mechanisms in living organisms, critical to an understanding of bioavailability, also presage the review. Transport of lipophilic chemicals occurs mainly by passive diffusion for all microorganisms, plants, and soil fauna. Therefore, the distribution of a chemical between organisms and soil (bioavailable proportion) follows partition equilibrium theory. However, a chemical's bioavailability does not always follow partition equilibrium theory because of other interactions with soil, such as soil sorption, hysteretic desorption, effects of surfactants in pore water, formation of "bound residue", etc. Bioassays for estimating chemical bioavailability have been introduced with several targeted endpoints: microbial degradation, uptake by higher plants and soil fauna, and toxicity to organisms. However, there bioassays are often time consuming and laborious. Thus, mild extraction methods have been employed to estimate bioavailability of chemicals. Mild methods include sequential extraction using alcohols, hexane/water, supercritical fluids (carbon dioxide), aqueous hydroxypropyl-beta-cyclodextrin extraction, polymeric TENAX beads extraction, and poly(dimethylsiloxane)-coated solid-phase microextraction. It should be noted that mild extraction methods may predict bioavailability at the moment when measurements are carried out, but not the changes in bioavailability that may occur over time. Simulation models are needed to estimate better bioavailability as a function of exposure time. In the past, models have progressed significantly by addressing each group of organisms separately: microbial degradation, plant uptake via evapotranspiration processes, and uptake of soil fauna in their habitat. This approach has been used primarily because of wide differences in the physiology and behaviors of such disparate organisms. However, improvement of models is badly needed, Particularly to describe uptake processes by plant and animals that impinge on bioavailability. Although models are required to describe all important factors that may affect chemical bioavailability to individual organisms over time (e.g., sorption/desorption to soil/sediment, volatilization, dissolution, aging, "bound residue" formation, biodegradation, etc.), these models should be simplified, when possible, to limit the number of parameters to the practical minimum. Although significant scientific progress has been made in understanding the complexities in specific methodologies dedicated to determining bioavailability, no method has yet emerged to characterized bioavailability across a wide range of chemicals, organisms, and soils/sediments. The primary aim in studying bioavailability is to define options for addressing bioremediation or environmental toxicity (risk assessment), and that is unlikely to change. Because of its importance in estimating research is needed to more comprehensively address the key environmental issue of "bioavailability of chemicals in soil/sediment."
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Affiliation(s)
- Arata Katayama
- EcoTopia Science Institute, Nagoya University, 464-8603, Nagoya, Japan.
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Proença P, Teixeira H, Castanheira F, Pinheiro J, Monsanto PV, Marques EP, Vieira DN. Two fatal intoxication cases with imidacloprid: LC/MS analysis. Forensic Sci Int 2005; 153:75-80. [PMID: 15922528 DOI: 10.1016/j.forsciint.2005.04.015] [Citation(s) in RCA: 82] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Imidacloprid [1-(6-chloro-3pyridylmethyl)-N-nitroimidazolidin-2-ylideneamine] is a new and potent nitromethylene insecticide with high insecticidal activity at very low application rates. It is the first highly effective insecticide that, like nicotine, acts on the nervous system, causing blockage of postsynaptic nicotinergic acetylcholine receptors. Two fatal cases with this insecticide in two male individuals, of 33 and 66 years old, are presented. An LC/MS with electrospray method for measuring imidacloprid and its metabolites in post-mortem samples is described. In the chromatographic separation, a reverse-phase column XTerra MS C18 (2.1mm i.d.x 150 mm, 5 microm) was used and the mobile phase composed with acetonitrile and 0.1% formic acid (15:85), at a 0.25 mL/min flow rate. Samples were prepared with a liquid-liquid extraction procedure with dichloromethane. Calibration curves for imidacloprid in blood and urine samples were linear from 0.2 to 15 microg/mL. The mean recovery was 86% with a coefficient of variation of +/-5.9%. The detection limit was 0.002 microg/mL. Quantitative results were obtained for all post-mortem matrices available of the two fatal cases: blood, urine, stomach contents, lung, liver and kidney. The imidacloprid blood concentrations found in two-cases were 12.5 and 2.05 microg/mL. The authors validated a method to detect and quantify imidacloprid in post-mortem samples, and to our knowledge for the first time a post-mortem tissue distribution was performed on various samples for this insecticide.
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Affiliation(s)
- Paula Proença
- National Institute of Legal Medicine, Delegation of Coimbra, Largo da Sé Nova, 3000-213 Coimbra, Portugal.
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Bonmatin JM, Marchand PA, Charvet R, Moineau I, Bengsch ER, Colin ME. Quantification of imidacloprid uptake in maize crops. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2005; 53:5336-41. [PMID: 15969515 DOI: 10.1021/jf0479362] [Citation(s) in RCA: 94] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/03/2023]
Abstract
The systemic imidacloprid is one of the most used insecticides in the world for field and horticultural crops. This neurotoxicant is often used as seed-dressing, especially for maize, sunflower, and rape. Using a LC/MS/MS technique (LOQ = 1 microg/kg and LOD = 0.1 microg/kg), the presence of imidacloprid has been measured in maize from field samples at the time of pollen shed, from less than 0.1 microg/kg up to 33.6 microg/kg. Numerous random samples were collected throughout France from 2000 to 2003. The average levels of imidacloprid measured are 4.1 microg/kg in stems and leaves, 6.6 microg/kg in male flowers (panicles), and 2.1 microg/kg in pollen. These values are similar to those found previously in sunflower and rape. These results permit evaluation of the risk to honeybees by using the PEC/PNEC ratios (probable exposition concentrations/predicted no effect concentration). PEC/PNEC risk ratios were determined and ranged between 500 and 600 for honeybees foraging on maize treated with imidacloprid by seed dressing. Such a high risk factor can be related to one of the main causes of honeybee colony losses.
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Affiliation(s)
- J M Bonmatin
- Centre de biophysique moléculaire, CNRS (Centre National de la Recherche Scientifique) & Université d'Orléans, France.
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Charvet R, Katouzian-Safadi M, Colin ME, Marchand PA, Bonmatin JM. Insecticides systémiques : de nouveaux risques pour les insectes pollinisateurs. ANNALES PHARMACEUTIQUES FRANÇAISES 2004; 62:29-35. [PMID: 14747770 DOI: 10.1016/s0003-4509(04)94278-2] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
Imidacloprid, a new systemic insecticide used as seed-dressing, has been widely used in France since 1994. Its application mode and its efficiency allow a significant reduction in comparison with the usual quantity of chemicals used during pulverising treatment. But the insecticide imidacloprid is suspected to have harmful effects on the pollinators as many bees have died since its introduction. Recent studies have shown that imidacloprid has chronic and sub-lethal toxicities at levels of micro g/kg or less. It was therefore necessary to detect imidacloprid at these levels in soils, plants, flowers, and pollens. With this aim, we characterised the bio-availability of imidacloprid in the environment using a new quantitative analytical method, as a basis for the evaluation of the risk for bees.
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Affiliation(s)
- R Charvet
- Centre de Biophysique Moléculaire, CNRS et Université Orléans, F45071 Orléans Cedex 02
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Brunet JL, Maresca M, Fantini J, Belzunces LP. Human intestinal absorption of imidacloprid with Caco-2 cells as enterocyte model. Toxicol Appl Pharmacol 2004; 194:1-9. [PMID: 14728974 DOI: 10.1016/j.taap.2003.08.018] [Citation(s) in RCA: 49] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
In order to assess the risk to mammals of a chronic exposure to imidacloprid (IMI), we investigated its absorption with the human intestinal Caco-2 cell line. Measurements of transepithelial transport revealed an apparent permeability coefficient of 21.6 x 10(-6) +/- 3.2 x 10(-6) cm/s reflecting a 100% absorption. The comparison of apical to basal (A-B) and basal to apical (B-A) transports showed that the monolayer presents a basal to apical polarized transport. Studies of apical uptake demonstrated that the transport was concentration-dependent and not saturable from 5 to 200 microM. Arrhenius plot analysis revealed two apparent activation energies, Ea(4-12 degrees C) = 63.8 kJ/mol and Ea(12-37 degrees C) = 18.2 kJ/mol, suggesting two temperature-dependent processes. IMI uptake was equivalent when it was performed at pH 6.0 or 7.4. Depletion of Na+ from the transport buffer did not affect the uptake, indicating that a sodium-dependent transporter was not involved. Decrease of uptake with sodium-azide or after cell surface trypsin (Ti) treatment suggested the involvement of a trypsin-sensitive ATP-dependent transporter. Investigations on apical efflux demonstrated that initial velocities paralleled the increase of loading concentrations. A cell surface trypsin treatment did not affect the apical efflux. The lack of effect when the efflux was performed against an IMI concentration gradient suggested that an energy-dependent transporter was involved. However, the inhibition of P-glycoproteins (P-gp) and multidrug resistance-associated proteins (MRP) by taxol, vincristine, and daunorubicine had no effect on IMI intracellular accumulation suggesting the involvement of transporters distinct from classical ATP binding cassette transport (ABC-transport) systems. All results suggest that IMI is strongly absorbed in vivo by inward and outward active transporters.
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Affiliation(s)
- Jean-Luc Brunet
- Laboratoire de Toxicologie Environnementale, UMR 406 INRA-UAPV, INRA, Site Agroparc, 84914 Cedex 9, Avignon, France
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