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Hirashima S, Amimoto T, Iwamoto Y, Takeda K. Photodegradation of the insecticide fipronil in aquatic environments: photo-dechlorination processes and products. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2023; 30:89877-89888. [PMID: 37460889 DOI: 10.1007/s11356-023-28571-0] [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: 03/27/2023] [Accepted: 06/29/2023] [Indexed: 08/11/2023]
Abstract
Fipronil (FIP) is a phenylpyrazole insecticide that, along with neonicotinoid insecticides, is regularly used worldwide. Photodegradation of FIP in aqueous systems is thought mainly to involve the reaction of desulfinylation to give fipronil desulfinyl (FIP-desulfinyl); however, little is known about further degradation reactions. We investigated FIP photodegradation by analyzing photodegradation products by liquid chromatography and liquid chromatography high-resolution tandem mass spectrometry using an Orbitrap instrument. A wide range of products, including dechlorinated compounds, was detected, and the structures were identified. FIP-desulfinyl has previously been found to be an important and persistent FIP photodegradation product; however, we also found that FIP-desulfinyl was photochemically decomposed to a didechlorinated product via a monodechlorinated product. The main photodegradation pathway was probably similar to that of ethiprole, which has a similar skeleton. The photodegradation rate constant was 22.6 times lower for FIP-desulfinyl (0.00372 min-1) than FIP (0.0839 min-1). The photodegradation rate constant was lower for the newly found didechlorinated product (0.001 min-1 or below) than FIP-desulfinyl, suggesting that the product is persistent in aquatic environments and could be an important indicator of long-term FIP contamination.
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Affiliation(s)
- Soichiro Hirashima
- Graduate School of Integrated Sciences for Life, Hiroshima University, 1-7-1 Kagamiyama, Higashi-Hiroshima, 739-8521, Japan
| | - Tomoko Amimoto
- Natural Science Center for Basic Research and Development, Hiroshima University, 1-3-1 Kagamiyama, Higashi-Hiroshima, 739-8526, Japan
| | - Yoko Iwamoto
- Graduate School of Integrated Sciences for Life, Hiroshima University, 1-7-1 Kagamiyama, Higashi-Hiroshima, 739-8521, Japan
- Faculty of Integrated Arts and Sciences, Hiroshima University, 1-7-1 Kagamiyama, Higashi-Hiroshima, 739-8521, Japan
| | - Kazuhiko Takeda
- Graduate School of Integrated Sciences for Life, Hiroshima University, 1-7-1 Kagamiyama, Higashi-Hiroshima, 739-8521, Japan.
- Faculty of Integrated Arts and Sciences, Hiroshima University, 1-7-1 Kagamiyama, Higashi-Hiroshima, 739-8521, Japan.
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Eads DA, Livieri TM, Dobesh P, Hughes JP, Fly J, Redmond H, Childers E, Schwarz MS, Biggins DE. Plague mitigation for prairie dog and black-footed ferret conservation: Degree and duration of flea control with 0.005% fipronil grain bait. CURRENT RESEARCH IN PARASITOLOGY & VECTOR-BORNE DISEASES 2023; 3:100124. [PMID: 37305434 PMCID: PMC10250916 DOI: 10.1016/j.crpvbd.2023.100124] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/06/2023] [Revised: 05/11/2023] [Accepted: 05/15/2023] [Indexed: 06/13/2023]
Abstract
Sylvatic plague, a primarily flea-borne zoonosis, is a significant threat to prairie dogs (Cynomys spp., PDs) and their specialized predators, endangered black-footed ferrets (Mustela nigripes, BFFs). Host-fed fipronil baits have proven effective in controlling fleas on PDs for the purposes of plague mitigation and BFF conservation. Currently, annual treatments are the norm. We tested the long-term efficacy of fipronil bait treatments with black-tailed PDs (C. ludovicianus, BTPDs) and BFFs in South Dakota, USA. During 2018-2020, we provided BTPDs on 21 sites with grain bait formula, laced with 0.005% fipronil (50 mg/kg); 18 non-treated sites functioned as baselines. In 2020-2022, we live-trapped, anesthetized, and combed BTPDs for fleas. Flea control was significant for at least 639-885 days. Flea abundance on the treated sites was < 0.5 fleas/BTPD for ∼750 days. During 2020-2022, we sampled BFFs for fleas on 4 BTPD colonies treated with fipronil grain bait and 8 non-treated colonies. Flea control was significant with BFFs, but flea abundance began to rebound within ∼240 days post-treatment. When feasible, the combination of insecticide treatments, such as fipronil baits, and BFF vaccination against plague provide a "two-pronged" protection approach for these endangered carnivores. If fipronil bait treatments are less effective with predatory BFFs than PDs, as found herein, the "two-pronged" approach might be used to protect BFFs and biennial fipronil bait treatments might be used to protect PDs. If BFF vaccination is not possible, or few BFFs can be vaccinated, annual fipronil bait treatments might be used as a precaution to protect BFFs. Flea densities might be surveyed to determine when/where more frequent treatments seem useful.
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Affiliation(s)
- David A. Eads
- U. S. Geological Survey, Fort Collins Science Center, Fort Collins, CO, USA
| | | | - Phillip Dobesh
- U. S. Forest Service, Wall Ranger District, Wall, SD, USA
| | - John P. Hughes
- U. S. Fish and Wildlife Service, National Black-footed Ferret Conservation Center, Carr, CO, USA
| | - Jason Fly
- U. S. Geological Survey, Fort Collins Science Center, Fort Collins, CO, USA
| | - Holly Redmond
- U. S. Geological Survey, Fort Collins Science Center, Fort Collins, CO, USA
| | - Eddie Childers
- National Park Service, Badlands National Park, Interior, SD, USA
| | - Matthew S. Schwarz
- U. S. Fish and Wildlife Service, South Dakota Field Office, Pierre, SD, USA
| | - Dean E. Biggins
- U. S. Geological Survey, Fort Collins Science Center, Fort Collins, CO, USA
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Photodegradation of Fipronil by Zn-AlPO4 Materials Synthesized by Non-Hydrolytic Sol–Gel Method. CHEMENGINEERING 2022. [DOI: 10.3390/chemengineering6040055] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
In recent decades, the increasing use of pesticides to improve food productivity has led to the release of effluents that contaminate the environment. To prepare a material that may help to treat effluents generated during agricultural practice, we used a new method based on the non-hydrolytic sol-gel route to obtain zinc photocatalysts in aluminophosphate matrixes. IR spectroscopy, X-ray diffraction, thermal analysis, differential scanning electron microscopy, energy dispersion spectroscopy, and specific surface area and pore volume determined from the nitrogen adsorbed were used to characterize materials treated at different temperatures. X-ray analysis showed how heat-treatment affected the structure of the material: Zn-AlPO4 in the trigonal and orthorhombic phase was obtained at 750 and 1000 °C, respectively. These phases directly influenced the ability of the material to generate OH radicals. The capacity of the materials to treat effluents was tested in the photodegradation of the pesticide Fipronil. The photocatalytic reactions were monitored by ultraviolet-visible spectroscopy and gas chromatography-mass spectrometry analyses. Zn-AlPO4 treated at 750 °C showed better photodegradation results--it removed 80% of the pesticide in 2 h when higher mass (150 mg) was tested. Long-time treatment of the effluent with Zn-AlPO4 treated at 750 °C completely photodegraded Fipronil. GC-MS analysis confirmed the photodegration profile, and only traces of Fipronil were observed after photocatalytic reaction for 120 min in the presence of Zn-AlPO4 treated at 750 °C under UV radiation.
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Wan K, Jiang X, Tang X, Xiao L, Chen Y, Huang C, Zhu F, Wang F, Xu H. Study on Absorption, Distribution, Metabolism, and Excretion Properties of Novel Insecticidal GABA Receptor Antagonist, Pyraquinil, in Diamondback Moth Combining MALDI Mass Spectrometry Imaging and High-Resolution Mass Spectrometry. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2022; 70:6072-6083. [PMID: 35576451 DOI: 10.1021/acs.jafc.2c00468] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
A thorough understanding of absorption, distribution, metabolism, and excretion (ADME) of insecticide candidates is essential in insecticide development and structural optimization. Here, ADME of pyraquinil, a novel insecticidal GABA receptor antagonist, in Plutella xylostella larvae during the accumulation phase and depuration phase was investigated separately using a combination of UHPLC-Q-Orbitrap, HPLC-MS/MS, and MALDI-MSI. Five new metabolites of pyraquinil were identified, and a metabolic pathway was proposed. The oxidative metabolite (pyraquinil-sulfone) was identified as the main metabolite and confirmed by its standard. Quantitative results showed that pyraquinil was taken up by the larvae rapidly and then undergone a cytochrome P450s-mediated oxidative transformation into pyraquinil-sulfone. Both fecal excretion and oxidative metabolism were demonstrated to be predominant ways to eliminate pyraquinil in P. xylostella larvae during accumulation, while oxidative metabolism followed by fecal excretion was probably the major pathway during depuration. MALDI-MSI revealed that pyraquinil was homogeneously distributed in the larvae, while pyraquinil-sulfone presented a continuous enrichment in the midgut during accumulation. Conversely, pyraquinil-sulfone located in hemolymph can be preferentially eliminated during depuration, suggesting its tissue tropism. It improves the understanding of the fate of pyraquinil in P. xylostella and provides useful information for insecticidal mechanism elucidation and structural optimization of pyraquinil.
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Affiliation(s)
- Kai Wan
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-Bioresources and Key Laboratory of Natural Pesticide and Chemical Biology, Ministry of Education, South China Agricultural University, Guangzhou 510640, China
- Institute of Quality Standard and Monitoring Technology for Agro-products of Guangdong Academy of Agricultural Sciences and Guangdong Provincial Key Laboratory of Quality & Safety Risk Assessment for Agro-products, Guangzhou 510640, China
| | - Xunyuan Jiang
- Institute of Quality Standard and Monitoring Technology for Agro-products of Guangdong Academy of Agricultural Sciences and Guangdong Provincial Key Laboratory of Quality & Safety Risk Assessment for Agro-products, Guangzhou 510640, China
| | - Xuemei Tang
- Institute of Quality Standard and Monitoring Technology for Agro-products of Guangdong Academy of Agricultural Sciences and Guangdong Provincial Key Laboratory of Quality & Safety Risk Assessment for Agro-products, Guangzhou 510640, China
| | - Lu Xiao
- Institute of Quality Standard and Monitoring Technology for Agro-products of Guangdong Academy of Agricultural Sciences and Guangdong Provincial Key Laboratory of Quality & Safety Risk Assessment for Agro-products, Guangzhou 510640, China
| | - Yan Chen
- Institute of Quality Standard and Monitoring Technology for Agro-products of Guangdong Academy of Agricultural Sciences and Guangdong Provincial Key Laboratory of Quality & Safety Risk Assessment for Agro-products, Guangzhou 510640, China
| | - Congling Huang
- Institute of Quality Standard and Monitoring Technology for Agro-products of Guangdong Academy of Agricultural Sciences and Guangdong Provincial Key Laboratory of Quality & Safety Risk Assessment for Agro-products, Guangzhou 510640, China
| | - Fuwei Zhu
- Institute of Quality Standard and Monitoring Technology for Agro-products of Guangdong Academy of Agricultural Sciences and Guangdong Provincial Key Laboratory of Quality & Safety Risk Assessment for Agro-products, Guangzhou 510640, China
| | - Fuhua Wang
- Institute of Quality Standard and Monitoring Technology for Agro-products of Guangdong Academy of Agricultural Sciences and Guangdong Provincial Key Laboratory of Quality & Safety Risk Assessment for Agro-products, Guangzhou 510640, China
| | - Hanhong Xu
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-Bioresources and Key Laboratory of Natural Pesticide and Chemical Biology, Ministry of Education, South China Agricultural University, Guangzhou 510640, China
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Tao Y, Liu J, Xu Y, Liu H, Yang G, He Y, Xu J, Lu Z. Suspecting screening "known unknown" pesticides and transformation products in soil at pesticide manufacturing sites. THE SCIENCE OF THE TOTAL ENVIRONMENT 2022; 808:152074. [PMID: 34863759 DOI: 10.1016/j.scitotenv.2021.152074] [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: 09/22/2021] [Revised: 11/16/2021] [Accepted: 11/26/2021] [Indexed: 06/13/2023]
Abstract
The occurrence and risks of pesticides and their transformation products in soil at the manufacturing sites are "known unknowns." In this study, pesticides and their transformation products were screened in soil at 6 pesticide manufacturing sites across China using liquid and gas chromatography coupled with quadrupole time-of-flight mass spectrometry. The screening strategy can correctly identify 75% of 209 pesticides spiked at 50 ng g-1. A total of 212 pesticides were identified; 23.1% of pesticides detected were above 200 ng g-1, and the maximum concentration was 1.5 × 105 ng g-1. The risk quotients of 20% pesticides were greater than 1, and the maximum risk quotient of imidacloprid reached 6.3 × 104. The most recent site showed a larger number of pesticides with higher diversity, whereas older sites were dominated by organochlorine insecticides. The extended screen identified 163 transformation products with concentrations up to 6.6 × 104 ng g-1. Half of the transformation products had higher concentrations than their parent compounds, and metabolic ratios up to 371 were observed. The results of this study validate the prevalence of pesticides and their transformation products in soil at pesticide manufacturing sites. The results also highlight the importance of comprehensive screening at industrial sites and call for improved management and regulation of pesticide manufacturing, particularly for in-service facilities.
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Affiliation(s)
- Yufeng Tao
- Zhejiang Provincial Key Laboratory of Agricultural Resources and Environment, Institute of Soil and Water Resources and Environmental Science, College of Environmental and Resource Sciences, Zhejiang University, Hangzhou, Zhejiang 310058, China
| | - Jing Liu
- Zhejiang Provincial Key Laboratory of Agricultural Resources and Environment, Institute of Soil and Water Resources and Environmental Science, College of Environmental and Resource Sciences, Zhejiang University, Hangzhou, Zhejiang 310058, China
| | - Yiwen Xu
- Zhejiang Provincial Key Laboratory of Agricultural Resources and Environment, Institute of Soil and Water Resources and Environmental Science, College of Environmental and Resource Sciences, Zhejiang University, Hangzhou, Zhejiang 310058, China
| | - Hang Liu
- Zhejiang Provincial Key Laboratory of Agricultural Resources and Environment, Institute of Soil and Water Resources and Environmental Science, College of Environmental and Resource Sciences, Zhejiang University, Hangzhou, Zhejiang 310058, China
| | - Guiling Yang
- State Key Laboratory for Quality and Safety of Agro-products, Key Laboratory for Pesticide Residue Detection of Ministry of Agriculture, Laboratory (Hangzhou) for Risk Assessment of Agricultural Products of Ministry of Agriculture, Institute of Quality and Standard for Agro-products, Zhejiang Academy of Agricultural Sciences, Hangzhou, Zhejiang 310021, China
| | - Yan He
- Zhejiang Provincial Key Laboratory of Agricultural Resources and Environment, Institute of Soil and Water Resources and Environmental Science, College of Environmental and Resource Sciences, Zhejiang University, Hangzhou, Zhejiang 310058, China
| | - Jianming Xu
- Zhejiang Provincial Key Laboratory of Agricultural Resources and Environment, Institute of Soil and Water Resources and Environmental Science, College of Environmental and Resource Sciences, Zhejiang University, Hangzhou, Zhejiang 310058, China.
| | - Zhijiang Lu
- Department of Environmental Science and Geology, Wayne State University, Detroit, MI 48201, United States.
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Xu Z, Wan Y, Xia W, Zhou L, Wang A, Shi L, Guo Y, He Z, Xu S, Zhang R. Fipronil and its metabolites in human seminal plasma from Shijiazhuang, north China. CHEMOSPHERE 2022; 289:133238. [PMID: 34896427 DOI: 10.1016/j.chemosphere.2021.133238] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/23/2021] [Revised: 11/08/2021] [Accepted: 12/08/2021] [Indexed: 06/14/2023]
Abstract
Fipronil (FP) is an emerging insecticide which could induce reproductive toxicity in male rats at very low dosage, but the occurrence of FP and its transformation products (FPs) in human seminal plasma and their impacts on human semen quality have not been documented. In this study, FPs including FP, fipronil desulfinyl (FP-DES), fipronil sulfone (FP-SFO), fipronil amide (FP-AM), and fipronil sulfide (FP-SFI), were measured in seminal plasma samples (n = 200), which were collected from Shijiazhuang, north China. The cumulative concentration of FPs (ΣFPs), in the seminal plasma samples ranged from 0.003 to 0.180 ng/mL (median: 0.043 ng/mL). FP-SFO was the major target analyte (median: 0.040 ng/mL), accounting for approximately 42.3-100.0% of the ΣFPs. Significantly higher exposure levels of FPs were found in the overweight or obese group (≥25 kg/m2) vs. the normal BMI group (18.5-25 kg/m2) (ΣFPs: 0.047 vs. 0.033 ng/mL), never smoking group vs. current smoking group (ΣFPs: 0.057 vs. 0.037 ng/mL), and low sexual frequency group (<1 time/week) vs. high sexual frequency group (≥3 times/week) (ΣFPs: 0.048 vs. 0.030 ng/mL). No significant association between FPs and impaired semen quality parameter was found in this study. This is the first time to report FPs' occurrence in human seminal plasma and variations in their concentrations among people with different demographic and behavioral characteristics. Further studies on adverse effects of exposure to FPs on reproductive function are needed.
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Affiliation(s)
- Ziyuan Xu
- Key Laboratory of Environment and Health (HUST), Ministry of Education & Ministry of Environmental Protection, And State Key Laboratory of Environmental Health (Incubation), School of Public Health, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, 430030, PR China.
| | - Yanjian Wan
- Institute of Environmental Health, Wuhan Centers for Disease Control & Prevention, Wuhan, Hubei, 430024, PR China.
| | - Wei Xia
- Key Laboratory of Environment and Health (HUST), Ministry of Education & Ministry of Environmental Protection, And State Key Laboratory of Environmental Health (Incubation), School of Public Health, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, 430030, PR China.
| | - Lixiao Zhou
- Department of Toxicology, School of Public Health, Hebei Medical University, Shijiazhuang, 050017, PR China; Hebei Key Laboratory of Environment and Human Health, Shijiazhuang, 050017, PR China.
| | - Aizhen Wang
- Key Laboratory of Environment and Health (HUST), Ministry of Education & Ministry of Environmental Protection, And State Key Laboratory of Environmental Health (Incubation), School of Public Health, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, 430030, PR China.
| | - Lisha Shi
- Division of Public Health Service and Safety Assessment, Shanghai Municipal Center for Disease Control and Prevention, Shanghai, 200336, PR China.
| | - Yinsheng Guo
- Environment and Health Department, Shenzhen Center for Disease Control and Prevention, Shenzhen, Guangdong, 518055, PR China.
| | - Zhenyu He
- Institute of Environmental Health, Wuhan Centers for Disease Control & Prevention, Wuhan, Hubei, 430024, PR China.
| | - Shunqing Xu
- Key Laboratory of Environment and Health (HUST), Ministry of Education & Ministry of Environmental Protection, And State Key Laboratory of Environmental Health (Incubation), School of Public Health, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, 430030, PR China.
| | - Rong Zhang
- Department of Toxicology, School of Public Health, Hebei Medical University, Shijiazhuang, 050017, PR China; Hebei Key Laboratory of Environment and Human Health, Shijiazhuang, 050017, PR China.
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7
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Paolini L, Hausser N, Zhang T. Chiral resolution of the insecticide fipronil enantiomers and the simultaneous determination of its major transformation products by high-performance liquid chromatography interfaced with mass spectrometry. Chirality 2022; 34:473-483. [PMID: 35048416 DOI: 10.1002/chir.23412] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2021] [Revised: 12/18/2021] [Accepted: 12/20/2021] [Indexed: 01/09/2023]
Abstract
A high-performance liquid chromatography-mass spectrometry (HPLC-MS) method was developed using a chiral column based on amylose tris(3-chloro-5-methylphenylcarbamate) for analysis of fipronil (a popular insecticidal nerve agent) and the related transformation products. The optimized method reached the goal of the simultaneous and complete separation of the multiple fiproles in a single run, including the chiral separation of fipronil enantiomers, fipronil metabolites, and photoproducts. The efficacy of such a method was demonstrated by its application in analyzing a series of fipronil samples exposed to sunlight conditions. In general terms, our study provided experimental approaches and an efficient analytical tool for monitoring the environmental fate of fipronil as well as its multitransformation products upon its applications either in agricultural or any other areas.
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Affiliation(s)
- Léa Paolini
- R&D department, Chiral Technologies Europe, Illkirch Cedex, France
| | - Nicolas Hausser
- R&D department, Chiral Technologies Europe, Illkirch Cedex, France
| | - Tong Zhang
- R&D department, Chiral Technologies Europe, Illkirch Cedex, France
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Zhou Z, Wu X, Lin Z, Pang S, Mishra S, Chen S. Biodegradation of fipronil: current state of mechanisms of biodegradation and future perspectives. Appl Microbiol Biotechnol 2021; 105:7695-7708. [PMID: 34586458 DOI: 10.1007/s00253-021-11605-3] [Citation(s) in RCA: 29] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2021] [Revised: 09/15/2021] [Accepted: 09/17/2021] [Indexed: 02/02/2023]
Abstract
Fipronil is a broad-spectrum phenyl-pyrazole insecticide that is widely used in agriculture. However, in the environment, its residues are toxic to aquatic animals, crustaceans, bees, termites, rabbits, lizards, and humans, and it has been classified as a C carcinogen. Due to its residual environmental hazards, various effective approaches, such as adsorption, ozone oxidation, catalyst coupling, inorganic plasma degradation, and microbial degradation, have been developed. Biodegradation is deemed to be the most effective and environmentally friendly method, and several pure cultures of bacteria and fungi capable of degrading fipronil have been isolated and identified, including Streptomyces rochei, Paracoccus sp., Bacillus firmus, Bacillus thuringiensis, Bacillus spp., Stenotrophomonas acidaminiphila, and Aspergillus glaucus. The metabolic reactions of fipronil degradation appear to be the same in different bacteria and are mainly oxidation, reduction, photolysis, and hydrolysis. However, the enzymes and genes responsible for the degradation are somewhat different. The ligninolytic enzyme MnP, the cytochrome P450 enzyme, and esterase play key roles in different strains of bacteria and fungal. Many unanswered questions exist regarding the environmental fate and degradation mechanisms of this pesticide. The genes and enzymes responsible for biodegradation remain largely unexplained, and biomolecular techniques need to be applied in order to gain a comprehensive understanding of these issues. In this review, we summarize the literature on the degradation of fipronil, focusing on biodegradation pathways and identifying the main knowledge gaps that currently exist in order to inform future research. KEY POINTS: • Biodegradation is a powerful tool for the removal of fipronil. • Oxidation, reduction, photolysis, and hydrolysis play key roles in the degradation of fipronil. • Possible biochemical pathways of fipronil in the environment are described.
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Affiliation(s)
- Zhe Zhou
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-Bioresources, Guangdong Province Key Laboratory of Microbial Signals and Disease Control, Integrative Microbiology Research Centre, South China Agricultural University, Guangzhou, 510642, China.,Guangdong Laboratory for Lingnan Modern Agriculture, Guangzhou, 510642, China
| | - Xiaozhen Wu
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-Bioresources, Guangdong Province Key Laboratory of Microbial Signals and Disease Control, Integrative Microbiology Research Centre, South China Agricultural University, Guangzhou, 510642, China.,Guangdong Laboratory for Lingnan Modern Agriculture, Guangzhou, 510642, China
| | - Ziqiu Lin
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-Bioresources, Guangdong Province Key Laboratory of Microbial Signals and Disease Control, Integrative Microbiology Research Centre, South China Agricultural University, Guangzhou, 510642, China.,Guangdong Laboratory for Lingnan Modern Agriculture, Guangzhou, 510642, China
| | - Shimei Pang
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-Bioresources, Guangdong Province Key Laboratory of Microbial Signals and Disease Control, Integrative Microbiology Research Centre, South China Agricultural University, Guangzhou, 510642, China.,Guangdong Laboratory for Lingnan Modern Agriculture, Guangzhou, 510642, China
| | - Sandhya Mishra
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-Bioresources, Guangdong Province Key Laboratory of Microbial Signals and Disease Control, Integrative Microbiology Research Centre, South China Agricultural University, Guangzhou, 510642, China.,Guangdong Laboratory for Lingnan Modern Agriculture, Guangzhou, 510642, China
| | - Shaohua Chen
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-Bioresources, Guangdong Province Key Laboratory of Microbial Signals and Disease Control, Integrative Microbiology Research Centre, South China Agricultural University, Guangzhou, 510642, China. .,Guangdong Laboratory for Lingnan Modern Agriculture, Guangzhou, 510642, China.
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9
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Singh NS, Sharma R, Singh SK, Singh DK. A comprehensive review of environmental fate and degradation of fipronil and its toxic metabolites. ENVIRONMENTAL RESEARCH 2021; 199:111316. [PMID: 33989624 DOI: 10.1016/j.envres.2021.111316] [Citation(s) in RCA: 65] [Impact Index Per Article: 21.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/30/2020] [Revised: 05/07/2021] [Accepted: 05/07/2021] [Indexed: 06/12/2023]
Abstract
The use of pesticides to increase crop production has become one of the inevitable components of modern agriculture. Fipronil, a phenylpyrazoles insecticide, is one of the most widely used, systemic, broad-spectrum insecticides. Owing to its unique mode of action and selective toxicity, it was once regarded as safer alternatives to more toxic and persistent organochlorine insecticides. However, with the increased use, many studies have reported the toxicity of fipronil and its metabolites in various non-target organisms during the last two decades. Currently, it is regarded as one of the most persistent and lipophilic insecticides in the market. In the environment, fipronil can undergo oxidation, reduction, hydrolysis, or photolysis to form fipronil sulfone, fipronil sulfide, fipronil amide, or fipronil desulfinyl respectively. These metabolites except fipronil amide are more or less toxic and persistent than fipronil and have been reported from diverse environmental samples. Recently many studies have focused on the degradation and removal of fipronil residues from the environment. However, a comprehensive review summarizing and combining these recent findings is lacking. In the present review, we evaluate, summarize, and combine important findings from recent degradation studies of fipronil and its metabolites. An attempt has been made to elucidate the possible mechanism and pathways of degradation of fipronil and its toxic metabolites.
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Affiliation(s)
- Ngangbam Sarat Singh
- Department of Zoology, Dr. Sarvepalli Radhakrishnan Government Arts College, Yanam, Puducherry, 533464, India
| | - Ranju Sharma
- Pesticide Toxicology and Soil Microbial Ecology Lab, Department of Zoology, University of Delhi, Delhi, 110007, India.
| | - Sandeep Kumar Singh
- Department of Zoology, Ramjas College, University of Delhi, Delhi, 110007, India
| | - Dileep Kumar Singh
- Pesticide Toxicology and Soil Microbial Ecology Lab, Department of Zoology, University of Delhi, Delhi, 110007, India
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Shi L, Jiang Y, Wan Y, Huang J, Meng Q, He Z, Xu S, Xia W. Occurrence of the insecticide fipronil and its degradates in indoor dust from South, Central, and North China. THE SCIENCE OF THE TOTAL ENVIRONMENT 2020; 741:140110. [PMID: 32574918 DOI: 10.1016/j.scitotenv.2020.140110] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/08/2020] [Revised: 06/07/2020] [Accepted: 06/08/2020] [Indexed: 06/11/2023]
Abstract
No known data are available regarding the occurrence of fipronil (FP) in indoor dust in China, despite the fact that it is an emerging insecticide that is used extensively. In this study, FP and its derivatives (FPs), including fipronil sulfone (FP-SFO), fipronil sulfide, fipronil desulfinyl, and fipronil amide, were determined in indoor dust samples (n = 436) collected from three different cities in China between 2016 and 2019, namely Shenzhen (February and September 2019), Wuhan (October 2016, October 2018, and August 2019), and Taiyuan (October 2016), located in south, central, and north China, respectively. FP and FP-SFO were the major target analytes detected in all dust samples, accounting for approximately 68.6-90.1% of the cumulative concentration of FPs (ΣFPs). The ΣFPs values for the dust samples ranged from not detected (ND) to 33.6 μg/g (median ± median absolute deviation [MAD]: 7.12 ± 6.44 ng/g), with a detection frequency of 95.6%. The median value of the ΣFPs of the dust samples collected from Shenzhen (22.6 ± 15.6 ng/g) was higher than that found in the dust samples collected in Taiyuan 2016 (1.87 ± 1.65 ng/g) and Wuhan (6.43 ± 5.62 ng/g). Significantly higher ΣFPs were observed in the dust samples collected in urban areas than in the rural areas of Taiyuan and Wuhan. Furthermore, an increasing trend of FP (from 2016 to 2018) in the rural areas of Wuhan, and a seasonal variation (summer > autumn) in FP, FP-SFO, and ΣFPs in the dust samples from urban areas of Wuhan were observed. The estimated daily intake of FPs via dust ingestion for people in Shenzhen was approximately 12 times higher than in Taiyuan based on the samples analyzed. This is the first study to describe the occurrence and spatiotemporal variations of FPs in indoor dust in China.
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Affiliation(s)
- Lisha Shi
- Key Laboratory of Environment and Health (HUST), Ministry of Education & Ministry of Environmental Protection, State Key Laboratory of Environmental Health (Incubation), School of Public Health, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei 430030, PR China
| | - Ying Jiang
- Nanshan District Center for Disease Control and Prevention, Shenzhen, Guangdong 518054, PR China
| | - Yanjian Wan
- Wuhan Centers for Disease Prevention & Control, Wuhan, Hubei 430024, PR China
| | - Juan Huang
- Wuhan Centers for Disease Prevention & Control, Wuhan, Hubei 430024, PR China
| | - Qianqian Meng
- China Institute for Radiation Protection, Taiyuan, Shanxi 030006, PR China
| | - Zhenyu He
- Wuhan Centers for Disease Prevention & Control, Wuhan, Hubei 430024, PR China
| | - Shunqing Xu
- Key Laboratory of Environment and Health (HUST), Ministry of Education & Ministry of Environmental Protection, State Key Laboratory of Environmental Health (Incubation), School of Public Health, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei 430030, PR China
| | - Wei Xia
- Key Laboratory of Environment and Health (HUST), Ministry of Education & Ministry of Environmental Protection, State Key Laboratory of Environmental Health (Incubation), School of Public Health, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei 430030, PR China.
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11
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Smythe BG, Sanchez-Sandoval UA. General Considerations for On-Animal Ectoparasiticidal Product Evaluations. JOURNAL OF INSECT SCIENCE (ONLINE) 2020; 20:5948074. [PMID: 33135752 PMCID: PMC7604831 DOI: 10.1093/jisesa/ieaa042] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/13/2020] [Indexed: 06/11/2023]
Abstract
Successfully preparing for and conducting on-animal ectoparasiticidal evaluations is key in providing accurate results and inferences on product performance. However, the procedures associated with designing sound-reliable research projects while using animal test subjects can become complex. The current manuscript offers insights towards the characterization of different evaluation types highlighting key considerations and potential problematic barriers that may otherwise be overlooked by researchers new to the area of on-animal product evaluation. Furthermore, recommendations on reporting inferences from findings based on various study designs are discussed. The authors of the current manuscript offer these considerations in the hopes of maintaining harmony in future reports used to develop and evaluate on-animal ectoparsiticidal products in the field of veterinary entomology.
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Affiliation(s)
- Brandon G Smythe
- Center for Animal Health and Food Safety, New Mexico State University, Las Cruces, NM
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Gao J, Wang F, Jiang W, Miao J, Wang P, Zhou Z, Liu D. A full evaluation of chiral phenylpyrazole pesticide flufiprole and the metabolites to non-target organism in paddy field. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2020; 264:114808. [PMID: 32434115 DOI: 10.1016/j.envpol.2020.114808] [Citation(s) in RCA: 27] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/29/2020] [Revised: 05/09/2020] [Accepted: 05/12/2020] [Indexed: 05/27/2023]
Abstract
Pesticides applied to paddy fields may pose considerable danger to non-target aquatic organisms and further threaten human health. Flufiprole is a pesticide used in rice fields; considering the widespread existence of rice-fish-farming ecosystems, the acute toxicities of flufiprole enantiomers and its six metabolites (fipronil, flufiprole sulfide, flufiprole sulfone, detrifluoromethylsulfinyl flufiprole, desulfinyl flufiprole, and flufiprole amide) to four common aquatic organisms in rice fields including Misgurnus anguillicaudatus (pond loach), Carassius gibelio (Prussian carp), Pelophylax nigromaculatus (black-spotted frog), and Daphnia magna (water flea) were investigated. Genotoxicity, pathological changes and the effects on the antioxidant system of M. anguillicaudatus were also evaluated after exposure. The LC50 (EC50) values showed that fipronil and desulfinyl flufiprole were the most toxic compounds and were approximately about six times as toxic as flufiprole. No enantioselective toxicity was observed between the two enantiomers. The activity of antioxidant defense enzymes and the content of malondialdehyde (MDA) in the liver and gills of M. anguillicaudatus were significantly increased by the chemicals in most cases. In addition, fipronil and desulfinyl flufiprole were found to induce an increase in the micronucleus rate in M. anguillicaudatus. Histopathological analysis showed that the liver of M. anguillicaudatus was not significantly affected by flufiprole. Our study demonstrated a potential negative effect on flufiprole-treated aquatic organisms. As an alternative to fipronil, the environmental risk of flufiprole and its metabolites to non-target organisms in rice fields cannot be ignored.
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Affiliation(s)
- Jing Gao
- Beijing Advanced Innovation Centre for Food Nutrition and Human Health, Department of Applied Chemistry, China Agricultural University, No. 2 West Yuanmingyuan Road, Beijing, 100193, PR China
| | - Fang Wang
- Beijing Key Laboratory of Emerging Organic Contaminants Control, State Key Joint Laboratory of Environmental Simulation and Pollution Control, School of Environment, Tsinghua University, Beijing, 100084, PR China
| | - Wenqi Jiang
- Beijing Advanced Innovation Centre for Food Nutrition and Human Health, Department of Applied Chemistry, China Agricultural University, No. 2 West Yuanmingyuan Road, Beijing, 100193, PR China
| | - Jingwen Miao
- Beijing Advanced Innovation Centre for Food Nutrition and Human Health, Department of Applied Chemistry, China Agricultural University, No. 2 West Yuanmingyuan Road, Beijing, 100193, PR China
| | - Peng Wang
- Beijing Advanced Innovation Centre for Food Nutrition and Human Health, Department of Applied Chemistry, China Agricultural University, No. 2 West Yuanmingyuan Road, Beijing, 100193, PR China
| | - Zhiqiang Zhou
- Beijing Advanced Innovation Centre for Food Nutrition and Human Health, Department of Applied Chemistry, China Agricultural University, No. 2 West Yuanmingyuan Road, Beijing, 100193, PR China
| | - Donghui Liu
- Beijing Advanced Innovation Centre for Food Nutrition and Human Health, Department of Applied Chemistry, China Agricultural University, No. 2 West Yuanmingyuan Road, Beijing, 100193, PR China.
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Gao J, Wang F, Jiang W, Han J, Liu D, Zhou Z, Wang P. Tissue Distribution, Accumulation, and Metabolism of Chiral Flufiprole in Loach ( Misgurnus anguillicaudatus). JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2019; 67:14019-14026. [PMID: 31725274 DOI: 10.1021/acs.jafc.9b05083] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Flufiprole is an insecticide used in the rice field and may pose a potential threat to aquatic organisms including loach. To investigate the transformation products of flufiprole in loach, the accumulation, elimination, and tissue distribution in vivo as well as the metabolism in vitro at the enantiomeric level were studied. Flufiprole enantiomers rapidly accumulated and were metabolized to flufiprole sulfone, fipronil, and flufiprole amide in the tissues. Enantiomeric fractions showed the preferential accumulation and degradation of S-flufiprole. The residue of the chiral metabolite flufiprole amide was also enantioselective. The individual enantiomer treatment indicated that S-flufiprole was preferentially metabolized to flufiprole sulfone and R-flufiprole to fipronil. The metabolites were more persistent than flufiprole with longer half-lives. The metabolism in liver microsomes also reached consistent conclusions. The dietary risk assessment indicated that flufiprole would not cause unacceptable threats to human health. However, the metabolites of flufiprole should be considered in the risk evaluation.
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Affiliation(s)
- Jing Gao
- Beijing Advanced Innovation Centre for Food Nutrition and Human Health, Department of Applied Chemistry , China Agricultural University , No. 2 West Yuanmingyuan Road , Beijing 100193 , P. R. China
| | - Fang Wang
- Beijing Advanced Innovation Centre for Food Nutrition and Human Health, Department of Applied Chemistry , China Agricultural University , No. 2 West Yuanmingyuan Road , Beijing 100193 , P. R. China
- Beijing Key Laboratory of Emerging Organic Contaminants Control, State Key Joint Laboratory of Environmental Simulation and Pollution Control, School of Environment , Tsinghua University , Beijing 100084 , P. R. China
| | - Wenqi Jiang
- Beijing Advanced Innovation Centre for Food Nutrition and Human Health, Department of Applied Chemistry , China Agricultural University , No. 2 West Yuanmingyuan Road , Beijing 100193 , P. R. China
| | - Jiajun Han
- Department of Chemistry , University of Toronto , 80 St. George Street , Toronto M5S 3H6 , Ontario , Canada
| | - Donghui Liu
- Beijing Advanced Innovation Centre for Food Nutrition and Human Health, Department of Applied Chemistry , China Agricultural University , No. 2 West Yuanmingyuan Road , Beijing 100193 , P. R. China
| | - Zhiqiang Zhou
- Beijing Advanced Innovation Centre for Food Nutrition and Human Health, Department of Applied Chemistry , China Agricultural University , No. 2 West Yuanmingyuan Road , Beijing 100193 , P. R. China
| | - Peng Wang
- Beijing Advanced Innovation Centre for Food Nutrition and Human Health, Department of Applied Chemistry , China Agricultural University , No. 2 West Yuanmingyuan Road , Beijing 100193 , P. R. China
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Peribáñez MÁ, Calvete C, Gracia MJ. Preferences of Pet Owners in Regard to the Use of Insecticides for Flea Control. JOURNAL OF MEDICAL ENTOMOLOGY 2018; 55:1254-1263. [PMID: 29878139 DOI: 10.1093/jme/tjy088] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/26/2018] [Indexed: 06/08/2023]
Abstract
A survey conducted from 2002 to 2012 of 759 customers from 84 veterinary practices allows us to examine the habits of dog and cat owners regarding the use of insecticides for flea control. The results indicate that the percentage of animals treated during the 12 mo prior to the survey was not very high (71% in dogs and 50% in cats), considering that 100% of animals included in the study were flea-infested. Statistical analysis shows that animals older than 4 mo are treated more frequently and that dogs are more likely to be treated than cats. Among cats, those living in houses with gardens or farms are treated at a higher rate than those that live in houses without gardens or in flats. The main variable associated with the degree of satisfaction and product loyalty is the active ingredient, and the choice of a commercial product is generally associated with high-efficacy products. The mode of application of a flea treatment does not seem to have a strong influence on pet owner satisfaction or loyalty. Likewise, we do not find a clear correlation between owners' satisfaction and loyalty, so pet owners may find the results of the selected product more or less satisfactory for reasons other than simple effectiveness. Finally, because of the complexity of the life cycle of these ectoparasites, the importance of the advice of a veterinarian when planning flea control is emphasized.
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Affiliation(s)
- Miguel Ángel Peribáñez
- Departamento de Patología Animal, Facultad de Veterinaria, Universidad de Zaragoza, C/Miguel Servet, Zaragoza, Spain
| | - Carlos Calvete
- Unidad de Sanidad Animal, Centro de Investigación y Tecnología Agroalimentaria, CITA, IUI Mixto Agroalimentario de Aragón (IA2) (CITA-Universidad de Zaragoza), Avda. Montañana, Zaragoza, Spain
| | - María Jesús Gracia
- Departamento de Patología Animal, Facultad de Veterinaria, Universidad de Zaragoza, C/Miguel Servet, Zaragoza, Spain
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15
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Lao W, Hong Y, Tsukada D, Maruya KA, Gan J. A New Film-Based Passive Sampler for Moderately Hydrophobic Organic Compounds. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2016; 50:13470-13476. [PMID: 27993079 DOI: 10.1021/acs.est.6b04750] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
Passive samplers for moderately hydrophobic organic compounds (MHOCs) (i.e., log Kow ranging from 2 to 5) are under-developed compared to those that target polar or strongly hydrophobic compounds. The goal of this study was to identify a suitable polymer and develop a robust and sensitive film-based passive sampler for MHOCs in aquatic systems. Poly(methyl methacrylate) (PMMA) exhibited the highest affinity for fipronil and its three metabolites (i.e., fipronils) (log Kow 2.4-4.8) as model MHOCs compared with polyethylene and nylon films. In addition, a 30-60 min treatment of PMMA in ethyl ether was found to increase its sorption capacity by a factor of 10. Fipronils and 108 additional compounds (log Kow 2.4-8.5) reached equilibrium on solvent-treated PMMA within 120 h under mixing conditions and their uptake closely followed first-order kinetics. PMMA-water partition coefficients and Kow revealed an inverse parabolic relationship, with vertex at log Kow of 4.21 ± 0.19, suggesting that PMMA was ideal for MHOCs. The PMMA sampler was tested in an urban surface stream, and in spiked sediment. The results demonstrated that PMMA film, after a simple solvent swelling treatment, may be used as an effective passive sampler for determining Cfree of MHOCs in aquatic environments.
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Affiliation(s)
- Wenjian Lao
- Southern California Coast Water Research Project Authority, Costa Mesa, 92626, California, United States
| | - Youwei Hong
- Southern California Coast Water Research Project Authority, Costa Mesa, 92626, California, United States
- Department of Environmental Sciences, University of California , Riverside, 92521, California, United States
- Institute of Urban Environment, Chinese Academy of Sciences , Xiamen, 361021, China
| | - David Tsukada
- Southern California Coast Water Research Project Authority, Costa Mesa, 92626, California, United States
| | - Keith A Maruya
- Southern California Coast Water Research Project Authority, Costa Mesa, 92626, California, United States
| | - Jay Gan
- Department of Environmental Sciences, University of California , Riverside, 92521, California, United States
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16
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Michel N, Freese M, Brinkmann M, Pohlmann JD, Hollert H, Kammann U, Haarich M, Theobald N, Gerwinski W, Rotard W, Hanel R. Fipronil and two of its transformation products in water and European eel from the river Elbe. THE SCIENCE OF THE TOTAL ENVIRONMENT 2016; 568:171-179. [PMID: 27289396 DOI: 10.1016/j.scitotenv.2016.05.210] [Citation(s) in RCA: 35] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/12/2016] [Revised: 05/29/2016] [Accepted: 05/30/2016] [Indexed: 06/06/2023]
Abstract
Fipronil is an insecticide which, based on its mode of action, is intended to be predominantly toxic towards insects. Fipronil bioaccumulates and some of its transformation products were reported to be similar or even more stable in the environment and to show an enhanced toxicity against non-target organisms compared to the parent compound. The current study investigated the occurrence of Fipronil and two of its transformation products, Fipronil-desulfinyl and Fipronil-sulfone, in water as well as muscle and liver samples of eels from the river Elbe (Germany). In water samples total concentrations of FIP, FIP-d and FIP-s ranged between 0.5-1.6ngL(-1) with FIP being the main component in all water samples followed by FIP-s and FIP-d. In contrast, FIP-s was the main component in muscle and liver tissues of eels with concentrations of 4.05±3.73ngg(-1) ww and 19.91±9.96ngg(-1) ww, respectively. Using a physiologically based toxicokinetic (PBTK) model for moderately hydrophobic organic chemicals, the different distributions of FIP, FIP-d and FIP-s in water and related tissue samples could be attributed to metabolic processes of eels. The measured concentrations in water of all analytes and their fractional distribution did not reflect the assumed seasonal application of FIP and it seems that the water was constantly contaminated with FIP, FIP-d and FIP-s.
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Affiliation(s)
- N Michel
- Thünen-Institute, Institute of Fisheries Ecology, Palmaille 9, 22767 Hamburg, Germany; Federal Maritime and Hydrographic Agency-Laboratory, Wüstland 2, 22589 Hamburg, Germany; TU Berlin, Department of Environmental Technology, Institute for Environmental Chemistry, Fasanenstr. 1a, 10623 Berlin, Germany.
| | - M Freese
- Thünen-Institute, Institute of Fisheries Ecology, Palmaille 9, 22767 Hamburg, Germany
| | - M Brinkmann
- RWTH Aachen University, Department of Ecosystem Analysis, Institute for Environmental Research, Worringerweg 1, 52074 Aachen, Germany
| | - J-D Pohlmann
- Thünen-Institute, Institute of Fisheries Ecology, Palmaille 9, 22767 Hamburg, Germany
| | - H Hollert
- RWTH Aachen University, Department of Ecosystem Analysis, Institute for Environmental Research, Worringerweg 1, 52074 Aachen, Germany
| | - U Kammann
- Thünen-Institute, Institute of Fisheries Ecology, Palmaille 9, 22767 Hamburg, Germany
| | - M Haarich
- Thünen-Institute, Institute of Fisheries Ecology, Palmaille 9, 22767 Hamburg, Germany
| | - N Theobald
- Federal Maritime and Hydrographic Agency-Laboratory, Wüstland 2, 22589 Hamburg, Germany
| | - W Gerwinski
- Federal Maritime and Hydrographic Agency-Laboratory, Wüstland 2, 22589 Hamburg, Germany
| | - W Rotard
- TU Berlin, Department of Environmental Technology, Institute for Environmental Chemistry, Fasanenstr. 1a, 10623 Berlin, Germany
| | - R Hanel
- Thünen-Institute, Institute of Fisheries Ecology, Palmaille 9, 22767 Hamburg, Germany
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Lin C, Miao Y, Qian M, Wang Q, Zhang H. Enantioselective Metabolism of Flufiprole in Rat and Human Liver Microsomes. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2016; 64:2371-2376. [PMID: 26938045 DOI: 10.1021/acs.jafc.5b05853] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
The enantioselective metabolism of flufiprole in rat and human liver microsomes in vitro was investigated in this study. The separation and determination were performed using a liquid chromatography system equipped with a triple-quadrupole mass spectrometer and a Lux Cellulose-2 chiral column. The enantioselective metabolism of rac-flufiprole was dramatically different in rat and human liver microsomes in the presence of the β-nicotinamide adenine dinucleotide phosphate regenerating system. The half-lives (t1/2) of flufiprole in rat and human liver microsomes were 7.22 and 21.00 min, respectively, for R-(+)-flufiprole, whereas the values were 11.75 and 17.75 min, respectively, for S-(-)-flufiprole. In addition, the Vmax of R-(+)-flufiprole was about 3-fold that of S-(-)-flufiprole in rat liver microsomes, whereas its value in the case of S-(-)-flufiprole was about 2-fold that of R-(+)-flufiprole in human liver microsomes. The CLint of rac-flufiprole also showed opposite enantioselectivy in rat and human liver microsomes. The different compositions and contents of metabolizing enzyme in the two liver microsomes might be the reasons for the difference in the metabolic behavior of the two enantiomers.
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Affiliation(s)
- Chunmian Lin
- College of Biological and Environmental Engineering, Zhejiang University of Technology , Hangzhou 310014, China
| | - Yelong Miao
- College of Biological and Environmental Engineering, Zhejiang University of Technology , Hangzhou 310014, China
| | - Mingrong Qian
- Institute of Quality and Standard for Agricultural Products, Zhejiang Academy of Agricultural Sciences , Hangzhou 310021, China
| | - Qiang Wang
- Institute of Quality and Standard for Agricultural Products, Zhejiang Academy of Agricultural Sciences , Hangzhou 310021, China
| | - Hu Zhang
- Institute of Quality and Standard for Agricultural Products, Zhejiang Academy of Agricultural Sciences , Hangzhou 310021, China
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Zhang Q, Shi H, Gao B, Tian M, Hua X, Wang M. Enantioseparation and determination of the chiral phenylpyrazole insecticide ethiprole in agricultural and environmental samples and its enantioselective degradation in soil. THE SCIENCE OF THE TOTAL ENVIRONMENT 2016; 542:845-853. [PMID: 26556749 DOI: 10.1016/j.scitotenv.2015.10.132] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/25/2015] [Revised: 10/26/2015] [Accepted: 10/26/2015] [Indexed: 06/05/2023]
Abstract
An effective method for the enantioselective determination of ethiprole enantiomers in agricultural and environmental samples was developed. The effects of solvent extraction, mobile phase and thermodynamic parameters for chiral recognition were fully investigated. Complete enantioseparation of the ethiprole enantiomers was achieved on a Lux Cellulose-2 column. The stereochemical structures of ethiprole enantiomers were also determined, and (R)-(+)-ethiprole was first eluted. The average recoveries were 82.7-104.9% with intra-day RSD of 1.7-8.2% in soil, cucumber, spinach, tomato, apple and peach under optimal conditions. Good linearity (R(2)≥0.9991) was obtained for all the matrix calibration curves within a range of 0.1 to 10 mg L(-1). The limits of detection for both enantiomers were estimated to be 0.008 mg kg(-1) in soil, cucumber, spinach and tomato and 0.012 mg kg(-1) in apple and peach, which were lower than the maximum residue levels established in Japan. The results indicate that the proposed method is convenient and reliable for the enantioselective detection of ethiprole in agricultural and environmental samples. The behavior of ethiprole in soil was studied under field conditions and the enantioselective degradation was observed with enantiomer fraction values varying from 0.494 to 0.884 during the experiment. The (R)-(+)-ethiprole (t1/2=11.6 d) degraded faster than (S)-(-)-ethiprole (t1/2=34.7 d). This report is the first describe a chiral analytical method and enantioselective behavior of ethiprole, and these results should be extremely useful for the risk evaluation of ethiprole in food and environmental safety.
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Affiliation(s)
- Qing Zhang
- Department of Pesticide Science, College of Plant Protection, Nanjing Agricultural University, State & Local Joint Engineering Research Center of Green Pesticide Invention and Application, Key Laboratory of Integrated Management of Crop Diseases and Pests, Ministry of Education, Nanjing 210095, PR China
| | - Haiyan Shi
- Department of Pesticide Science, College of Plant Protection, Nanjing Agricultural University, State & Local Joint Engineering Research Center of Green Pesticide Invention and Application, Key Laboratory of Integrated Management of Crop Diseases and Pests, Ministry of Education, Nanjing 210095, PR China
| | - Beibei Gao
- Department of Pesticide Science, College of Plant Protection, Nanjing Agricultural University, State & Local Joint Engineering Research Center of Green Pesticide Invention and Application, Key Laboratory of Integrated Management of Crop Diseases and Pests, Ministry of Education, Nanjing 210095, PR China
| | - Mingming Tian
- Department of Pesticide Science, College of Plant Protection, Nanjing Agricultural University, State & Local Joint Engineering Research Center of Green Pesticide Invention and Application, Key Laboratory of Integrated Management of Crop Diseases and Pests, Ministry of Education, Nanjing 210095, PR China
| | - Xiude Hua
- Department of Pesticide Science, College of Plant Protection, Nanjing Agricultural University, State & Local Joint Engineering Research Center of Green Pesticide Invention and Application, Key Laboratory of Integrated Management of Crop Diseases and Pests, Ministry of Education, Nanjing 210095, PR China
| | - Minghua Wang
- Department of Pesticide Science, College of Plant Protection, Nanjing Agricultural University, State & Local Joint Engineering Research Center of Green Pesticide Invention and Application, Key Laboratory of Integrated Management of Crop Diseases and Pests, Ministry of Education, Nanjing 210095, PR China.
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Design, synthesis, characterization, and antiproliferative activity of novel pyrazole-3-carboxylic acid derivatives. MONATSHEFTE FUR CHEMIE 2015. [DOI: 10.1007/s00706-015-1450-7] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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20
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Simon-Delso N, Amaral-Rogers V, Belzunces LP, Bonmatin JM, Chagnon M, Downs C, Furlan L, Gibbons DW, Giorio C, Girolami V, Goulson D, Kreutzweiser DP, Krupke CH, Liess M, Long E, McField M, Mineau P, Mitchell EAD, Morrissey CA, Noome DA, Pisa L, Settele J, Stark JD, Tapparo A, Van Dyck H, Van Praagh J, Van der Sluijs JP, Whitehorn PR, Wiemers M. Systemic insecticides (neonicotinoids and fipronil): trends, uses, mode of action and metabolites. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2015; 22:5-34. [PMID: 25233913 PMCID: PMC4284386 DOI: 10.1007/s11356-014-3470-y] [Citation(s) in RCA: 930] [Impact Index Per Article: 103.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/04/2014] [Accepted: 08/15/2014] [Indexed: 04/15/2023]
Abstract
Since their discovery in the late 1980s, neonicotinoid pesticides have become the most widely used class of insecticides worldwide, with large-scale applications ranging from plant protection (crops, vegetables, fruits), veterinary products, and biocides to invertebrate pest control in fish farming. In this review, we address the phenyl-pyrazole fipronil together with neonicotinoids because of similarities in their toxicity, physicochemical profiles, and presence in the environment. Neonicotinoids and fipronil currently account for approximately one third of the world insecticide market; the annual world production of the archetype neonicotinoid, imidacloprid, was estimated to be ca. 20,000 tonnes active substance in 2010. There were several reasons for the initial success of neonicotinoids and fipronil: (1) there was no known pesticide resistance in target pests, mainly because of their recent development, (2) their physicochemical properties included many advantages over previous generations of insecticides (i.e., organophosphates, carbamates, pyrethroids, etc.), and (3) they shared an assumed reduced operator and consumer risk. Due to their systemic nature, they are taken up by the roots or leaves and translocated to all parts of the plant, which, in turn, makes them effectively toxic to herbivorous insects. The toxicity persists for a variable period of time-depending on the plant, its growth stage, and the amount of pesticide applied. A wide variety of applications are available, including the most common prophylactic non-Good Agricultural Practices (GAP) application by seed coating. As a result of their extensive use and physicochemical properties, these substances can be found in all environmental compartments including soil, water, and air. Neonicotinoids and fipronil operate by disrupting neural transmission in the central nervous system of invertebrates. Neonicotinoids mimic the action of neurotransmitters, while fipronil inhibits neuronal receptors. In doing so, they continuously stimulate neurons leading ultimately to death of target invertebrates. Like virtually all insecticides, they can also have lethal and sublethal impacts on non-target organisms, including insect predators and vertebrates. Furthermore, a range of synergistic effects with other stressors have been documented. Here, we review extensively their metabolic pathways, showing how they form both compound-specific and common metabolites which can themselves be toxic. These may result in prolonged toxicity. Considering their wide commercial expansion, mode of action, the systemic properties in plants, persistence and environmental fate, coupled with limited information about the toxicity profiles of these compounds and their metabolites, neonicotinoids and fipronil may entail significant risks to the environment. A global evaluation of the potential collateral effects of their use is therefore timely. The present paper and subsequent chapters in this review of the global literature explore these risks and show a growing body of evidence that persistent, low concentrations of these insecticides pose serious risks of undesirable environmental impacts.
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Affiliation(s)
- N Simon-Delso
- Environmental Sciences, Copernicus Institute, Utrecht University, Heidelberglaan 2, 3584 CS, Utrecht, The Netherlands,
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Varloud M, Hodgkins E. Five-month comparative efficacy evaluation of three ectoparasiticides against adult cat fleas (Ctenocephalides felis), flea egg hatch and emergence, and adult brown dog ticks (Rhipicephalus sanguineus sensu lato) on dogs housed outdoors. Parasitol Res 2014; 114:965-73. [PMID: 25547077 PMCID: PMC4336410 DOI: 10.1007/s00436-014-4262-5] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2014] [Accepted: 12/15/2014] [Indexed: 11/30/2022]
Abstract
This study was designed to compare the efficacy of three topical combinations on dogs in outdoor conditions against adult cat fleas (Ctenocephalides felis), flea egg hatch and emergence, and against adult brown dog ticks (Rhipicephalus sanguineus sensu lato). Treatment was performed on day 0 with a placebo; dinotefuran, pyriproxifen and permethrin (DPP); fipronil and (S)-methoprene (FM) or imidacloprid and permethrin (IP). Dogs (n = 32), housed outdoors for 7 months, were treated monthly for four consecutive months (on days 0, 30, 60 and 90) and infested with ~100 unfed adult fleas on days 14, 55, 74, 115 and 150 and with ~50 unfed adult ticks on days 28, 44, 88 and 104. Adult fleas were counted and removed 24 h after infestation. Immediately after flea removal, dogs were reinfested with ~100 new adult fleas 72 h prior to egg collection for up to 48 h. Flea eggs were incubated for 32 days, and newly emerged adults were counted. Ticks were counted and removed 48 h after each infestation. FM had >90 % efficacy against fleas at each time point and variable efficacy against ticks (38.0–99.6 %). Efficacy of IP was <90 % against fleas at day 64 and against ticks at day 30 of the first post-treatment. No flea eggs were laid in the treated groups until infestation was carried out >60 days after the last treatment. Despite challenging weather conditions, DPP was highly effective, providing >90 % efficacy against adult ticks as well as adult and immature fleas at every time point of the study.
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Affiliation(s)
- Marie Varloud
- Ceva Santé Animale S. A, 10 Avenue de la Ballastière, 33500, Libourne, France,
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Hidaka H, Tsukamoto T, Mitsutsuka Y, Takamura T, Serpone N. Photochemical and Ga2O3-photoassisted decomposition of the insecticide Fipronil in aqueous media upon UVC radiation. NEW J CHEM 2014. [DOI: 10.1039/c4nj00527a] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Fipronil is degraded photolytically and photocatalytically (β-Ga2O3 and TiO2) in aqueous media under UVC illumination and under reductive and oxidative conditions.
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Affiliation(s)
- Hisao Hidaka
- Department of Chemistry
- Meisei Universtiy
- Tokyo, Japan
| | | | | | - Takeji Takamura
- Department of Chemistry
- Kanagawa Institute of Technology
- Atsugi, Japan
| | - Nick Serpone
- PhotoGreen Laboratory
- Dipartimento di Chimica
- Università di Pavia
- Pavia 27100, Italy
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Araújo TMR, Canela MC, Miranda PCML. Photochemical nitro-nitrite rearrangement in methyl parathion decay under tropical conditions. JOURNAL OF ENVIRONMENTAL SCIENCE AND HEALTH. PART. B, PESTICIDES, FOOD CONTAMINANTS, AND AGRICULTURAL WASTES 2013; 48:251-259. [PMID: 23374042 DOI: 10.1080/03601234.2013.743750] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
This work presents a study of the abiotic degradation of commercially available methyl parathion in aqueous solution at two different concentrations (88 mg/L and 200 μg/L). The effects of solar irradiation and the presence of humic acids were evaluated and revealed a synergistic response between them. The half-life of methyl parathion ranged from 4.9 to 37 days, and the experimental data also show that photochemical processes were the most relevant in this case. The only byproduct found in samples submitted to shadowed conditions was 4-nitrophenol. On the other hand, 4-nitrophenol, methyl paraoxon and a new degradation product (O,O-dimethyl O-p-hydroxyphenyl phosphorothioate) were detected when the samples were exposed directly to sunlight. This newly identified compound was prepared in the laboratory by thiophosphorylation of hydroquinone, and coelution experiments with authentic samples provided unambiguous confirmation of the presence of O,O-dimethyl O-p-hydroxy phenylphosphorothioate in samples.
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Reynaud S, Worms IAM, Veyrenc S, Portier J, Maitre A, Miaud C, Raveton M. Toxicokinetic of benzo[a]pyrene and fipronil in female green frogs (Pelophylax kl. esculentus). ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2012; 161:206-214. [PMID: 22230087 DOI: 10.1016/j.envpol.2011.10.029] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/04/2011] [Revised: 08/03/2011] [Accepted: 10/21/2011] [Indexed: 05/31/2023]
Abstract
A general consensus that an increased logK(ow) led to an increase in xenobiotic uptake and bioaccumulation is accepted. In this study we compared the toxicokinetics of two chemically different xenobiotics, i.e. benzo[a]pyrene and fipronil in female green frogs. Surprisingly, the uptake rates and the bioconcentration factors (BCF) of the two contaminants were not predicted by their logK(ow). The uptake rates obtained were of the same order of magnitude for the two contaminants and the BCFs measured for fipronil were about 3-fold higher than those obtained for benzo[a]pyrene. Fipronil appeared to be more recalcitrant than benzo[a]pyrene to detoxification processes leading to the accumulation of sulfone-fipronil especially in the ovaries. This phenomenon may explain reproductive influence of this contaminant described in other studies. Detoxification processes, including metabolism and the excretion of pollutants, are of importance when considering their persistence in aquatic organisms and trying to quantify their risks.
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Affiliation(s)
- Stéphane Reynaud
- Laboratoire d'Ecologie Alpine (LECA, UMR 5553 CNRS-Université), Equipe « Pollution Environnement Ecotoxicologie Ecoremediation » Domaine Universitaire de Saint-Martin d'Hères. 2233, rue de la piscine Bât D Biologie, BP 53, 38041 Grenoble Cedex 9, France.
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Llorent-Martínez EJ, Fernández-de Córdova ML, Ruiz-Medina A, Ortega-Barrales P. Reagentless Photochemically-Induced Fluorimetric Determination of Fipronil by Sequential-Injection Analysis. ANAL LETT 2011. [DOI: 10.1080/00032719.2011.553006] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/15/2022]
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Thuyet DQ, Watanabe H, Yamazaki K, Takagi K. Photodegradation of imidacloprid and fipronil in rice-paddy water. BULLETIN OF ENVIRONMENTAL CONTAMINATION AND TOXICOLOGY 2011; 86:548-553. [PMID: 21424709 DOI: 10.1007/s00128-011-0243-x] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/13/2010] [Accepted: 03/08/2011] [Indexed: 05/30/2023]
Abstract
Photodegradation of insecticides, imidacloprid and fipronil, in rice-paddy water under the ambient temperature was investigated. The initial concentrations were set at 58.8 and 3.1 μg/L for imidacloprid and fipronil, respectively, according to their reported initial concentrations in the rice-paddy field. The half-lives (DT(50)) of imidacloprid and fipronil were 24.2 and 36.7 h, respectively. Fipronil desulfinyl was detected as a major metabolite and fipronil sulfone was found to be a minor metabolite of fipronil in the photodegradation process. Detected mass of fipronil, fipronil desulfinyl, and fipronil sulfone at 79 h were 12.9%, 45.8%, and 5.2% of initial fipronil mass, respectively.
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Affiliation(s)
- Dang Quoc Thuyet
- Tokyo University of Agriculture and Technology, 3-5-8 Saiwaicho, Fuchu, Tokyo 183-8509, Japan
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Chen T, Fu F, Chen Z, Li D, Zhang L, Chen G. Study on the photodegradation and microbiological degradation of pirimicarb insecticide by using liquid chromatography coupled with ion-trap mass spectrometry. J Chromatogr A 2009; 1216:3217-22. [DOI: 10.1016/j.chroma.2009.02.022] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2008] [Revised: 01/24/2009] [Accepted: 02/09/2009] [Indexed: 10/21/2022]
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Aajoud A, Raveton M, Azrou-Isghi D, Tissut M, Ravanel P. How can the fipronil insecticide access phloem? JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2008; 56:3732-3737. [PMID: 18442251 DOI: 10.1021/jf800043h] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
Seeds of sunflower plants coated with the fipronil (14)C-insecticide were allowed to grow in the greenhouse. The distribution of the (14)C-compounds was studied in each part of the plant after three months. After 83 days of culture small amounts of (14)C-compounds were found in the inflorescence (0.6 per thousand of the seed deposit) which were fipronil itself or its lipophilic or hydrophilic metabolites. The (14)C-compounds were found in each part of the inflorescence (bracts, ray and disk florets containing pollen, akenes). The (14)C-concentration in the xylem sap evaluated at this stage was much too low to explain the accumulated amount in the inflorescence. Under controlled conditions in a culture chamber, it was then demonstrated that a net phloem transfer of (14)C-fipronil occurred from developed leaves to growing organs. This allowed us to suppose that a similar (14)C-fipronil phloem transfer could occur toward the inflorescence during its formation. A quantitative evaluation suggests that most of the labeled compounds at this stage were not coming from the leaves but from the roots and stem where storage compounds were hydrolyzed for sustaining inflorescence development.
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Affiliation(s)
- Asmae Aajoud
- Laboratoire d'Ecologie Alpine, Université Joseph Fourier, B.P. 53, F-38041 Grenoble Cedex 09, France
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Jones WJ, Mazur CS, Kenneke JF, Garrison AW. Enantioselective microbial transformation of the phenylpyrazole insecticide fipronil in anoxic sediments. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2007; 41:8301-8307. [PMID: 18200855 DOI: 10.1021/es071409s] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
Fipronil, a chiral insecticide, was biotransformed initially to fipronil sulfide in anoxic sediment slurries following a short lag period. Sulfidogenic or methanogenic sediments transformed fipronil with half-lives of approximately 35 and 40 days, respectively. In all microbially active sediment slurries tested, the transformation of fipronil to fipronil sulfide was enantioselective. In the sulfidogenic sediment slurry, the enantiomeric fraction (EF) of fipronil decreased from an initial racemic EF value of 0.46 to a value of 0.22 during the incubation period of active fipronil transformation, indicating preferential transformation of the S-(+)-enantiomer. A previously unidentified product, 5-amino1-[2,6-dichloro-4-(trifluoromethyl)-phenyl]-4-(trifluoromethylthio)-1-H-pyrazole-3-carboxyamide, or fipronil sulfide-amide, was detected in the sulfidogenic slurries and coincided with the loss of fipronil sulfide. Biota from methanogenic freshwater sediment slurries also transformed fipronil enantioselectively but with a preference for the R-(-)-enantiomer. In all microbially inhibited (autoclaved) sediment slurries tested, no changes in the enantiomeric fractions of fipronil were observed and only low levels (< 5% of the added fipronil) of the fipronil sulfide metabolite were detected. In defined (model) chemical experiments, solutions of pyrite (FeS2) and iron sulfide (FeS) non-enantioselectively transformed fipronil primarily to either 2,6-dichloro-4-(trifluoromethyl)-aniline or to fipronil sulfide and fipronil amide, respectively. This report provides the first experimental evidence of enantioselective microbial transformation of fipronil in a natural environment (soil, water, and sediment) as well as identification of a novel fipronil biotransformation product.
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Affiliation(s)
- W Jack Jones
- Ecosystems Research Division, National Exposure Research Laboratory, U.S. Environmental Protection Agency, 960 College Station Rd., Athens, Georgia 30605, USA.
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Raveton M, Aajoud A, Willison J, Cherifi M, Tissut M, Ravanel P. Soil distribution of fipronil and its metabolites originating from a seed-coated formulation. CHEMOSPHERE 2007; 69:1124-9. [PMID: 17509641 DOI: 10.1016/j.chemosphere.2007.03.063] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/05/2006] [Revised: 03/27/2007] [Accepted: 03/30/2007] [Indexed: 05/15/2023]
Abstract
Seed-coating with the insecticide fipronil has been intensively used in sunflower cultivation to control soil pests such as wireworms. A research project was undertaken to determine the soil distribution of fipronil and of its main phenylpyrazole metabolites. Under agronomic conditions, the quantity of fipronil in the seed-coat (437 microg/seed) decreased continuously during the cultivation period (3.9 microg day(-1) during the first two months; 0.3 microg day(-1) during the next four months). At the end of the cultivation period, 42% of all phenylpyrazole compounds remained in the seed-coat. Fipro nil was poorly mobile in soil, and at the end of the cultivation period it was mostly concentrated in the soil layer close to the seed (3240 microg kg(-1) soil). Starting from the seed-coating, a fipronil concentration gradient was measured in the soil, up to a distance of 11 cm from the seed. Degradation in the soil occurred at a moderate rate, probably due to the fact that water solubilization of the solid active ingredient present in the seed coating was rate limiting. Indeed, after 6 months of cultivation, only 51% of the fipronil seed-coating was found in the soil, about 7% having been absorbed by the sunflower plant, and 42% remaining in the seed coat. The predominant metabolites produced in the soil were sulfone-fipronil, sulfide-fipronil and amide-fipronil, which were produced at average rates of 5 microg kg(-1) soil day(-1), 3 microg kg(-1) soil day(-1), and 0.4 microg kg(-1) soil day(-1), respectively. In contrast, the photoproduct, desulfinyl-fipronil, was barely detected. All phenylpyrazole compounds were poorly mobile, except for the amide derivative, which is devoid of insecticidal activity in marked contrast to the other metabolites. Furthermore, detectable soil contamination was limited to a zone of about 11 cm around the seed.
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Affiliation(s)
- Muriel Raveton
- Equipe Pertubations Environnementales et Xénobiotiques, Laboratoire Ecologie Alpine, UMR CNRS No. 5553, Université Joseph Fourier, BP 53X, 38041 Grenoble Cedex 9, France.
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