Determination of fipronil insecticide and its sulfone metabolite in internal organs of white albino rats
Keywords:Fipronil, Fipronil Sulfone, Metabolism, Internal Animal Organs, GC-MS.
Fipronil is a popular insecticide against a wide range of household, urban, agricultural, animal pests. It gets converted into several metabolites in animals and humans but mainly to fipronil sulfone, which is more toxic and persistent. Therefore, the current study aimed to investigate the presence of fipronil and fipronil sulfone in tissues of internal organs of white albino rats using gas chromatography coupled with mass spectroscopy (GC-MS) after oral administration of rats of repetitive sublethal doses of fipronil for 14 days. Results showed that the R2 values of standard curves of detected compounds were 0.9871 and 0.9989 for FIP and fipronil sulfone, respectively with LOQ of fipronil and fipronil sulfone of 5 and 10 Âµg/g. Average recovery percentages were from 96.3Â±5.4 to 101Â±8.5% and 93.8Â±4.7 to 98.4Â±5.1% for fipronil and fipronil sulfone, respectively with RSD values lower than 10%. Fipronil was detected in all tested organs. It was concentrated with great amounts in the lungs, liver, and kidney followed by testes, spleen, and brain, while fipronil sulfone was detected in the liver, testes, spleen, and lungs tissues in descending order. Fipronil was biotransformed into fipronil sulfone at different organs of white albino rats and the GC-MS coupled with the QuEChERS extraction and clean-up method were efficient in detecting them in the internal organs of rats.
 Abbassy MA, Nassar AMK, Salim YMM, & Marzouk MA (2015) Toxic effects of residue amounts of chlorpyrifos-methyl in tomato to white albino rats. Res J Environ Toxicol 9:241â€“250. https://doi.org/10.3923/rjet.2015.241.250.
 AOAC (2007) Pesticide Residues in Foods by Acetonitrile Extraction and Partitioning with Magnesium Sulfate Gas Chromatography/Mass Spectrometry and Liquid Chromatography/Tandem Mass Spectrometry First Action 2007. AOAC Int, Gaithersburg, USA
 Bichon E, Richard CA, & Le Bizec B (2008) Development and validation of a method for fipronil residue determination in ovine plasma using 96-well plate solid-phase extraction and gas chromatography-tandem mass spectrometry. J Chromatogr A 1201:91â€“99. https://doi.org/10.1016/j.chroma.2008.06.024.
 Branch SK (2005) Guidelines from the International Conference on Harmonisation (ICH). J. Pharm. Biomed. Anal. 38:798â€“805 https://doi.org/10.1016/j.jpba.2005.02.037.
 Cid YP, Ferreira TP, Medeiros DMVC, et al (2012) Determination of fipronil in bovine plasma by solid-phase extraction and liquid chromatography with ultraviolet detection. Quim Nova 35:2063â€“2066. https://doi.org/10.1590/S0100-40422012001000029.
 Cravedi JP, Delous G, Zalko D, et al (2013) Disposition of fipronil in rats. Chemosphere 93:2276â€“2283. https://doi.org/10.1016/j.chemosphere.2013.07.083.
 FDA (2018) Bioanalytical Method Validation Guidance for Industry
 Gan J, Bondarenko S, Oki L, et al (2012) Occurrence of fipronil and its biologically active derivatives in urban residential runoff. Environ Sci Technol 46:1489â€“1495. https://doi.org/10.1021/es202904x.
 Gunasekara AS, Truong T, Goh KS, et al (2007) Environmental fate and toxicology of fipronil. J Pestic Sci 32:189â€“199. https://doi.org/10.1584/jpestics.R07-02.
 Hainzl D & Casida JE (1996) Fipronil insecticide: Novel photochemical desulfinylation with retention of neurotoxicity. Proc Natl Acad Sci 93:12764â€“12767. https://doi.org/10.1073/pnas.93.23.12764.
 Hainzl D, Cole LM, & Casida JE (1998) Mechanisms for selective toxicity of fipronil insecticide and its sulfone metabolite and desulfinyl photoproduct. Chem Res Toxicol 11:1529â€“1535. https://doi.org/10.1021/tx980157t.
 Ikeda T, Nagata K, Kono Y, et al (2004) Fipronil modulation of GABAA receptor single-channel currents. Pest Manag Sci 60:487â€“492. https://doi.org/10.1002/ps.830.
 JimÃ©nez JJ, Bernal JL, del Nozal MJ, et al (2008) Sample preparation methods to analyze fipronil in honey by gas chromatography with electron-capture and mass spectrometric detection. J Chromatogr A 1187:40â€“45. https://doi.org/10.1016/j.chroma.2008.02.014.
 Kadar A & Faucon J-P (2006) Determination of Traces of Fipronil and Its Metabolites in Pollen by Liquid Chromatography with Electrospray Ionizationâˆ’Tandem Mass Spectrometry. J Agric Food Chem 54:9741â€“9746. https://doi.org/10.1021/jf062035.
 Lacroix MZ, Puel S, Toutain PL, & ViguiÃ© C (2010) Quantification of fipronil and its metabolite fipronil sulfone in rat plasma over a wide range of concentrations by LC/UV/MS. J Chromatogr B Anal Technol Biomed Life Sci 878:1934â€“1938. https://doi.org/10.1016/j.jchromb.2010.05.018.
 Le Faouder J, Bichon E, Brunschwig P, et al (2007) Transfer assessment of fipronil residues from feed to cow milk. Talanta 73:710â€“717. https://doi.org/10.1016/j.talanta.2007.04.061.
 Leghait J, Gayrard V, Picard-Hagen N, et al (2009) Fipronil-induced disruption of thyroid function in rats is mediated by increased total and free thyroxine clearances concomitantly to increased activity of hepatic enzymes. Toxicology 255:38â€“44. https://doi.org/10.1016/j.tox.2008.09.026.
 McMahen RL, Strynar MJ, Dagnino S, et al (2015) Identification of fipronil metabolites by time-of-flight mass spectrometry for application in a human exposure study. Environ Int 78:16â€“23. https://doi.org/10.1016/j.envint.2015.01.016.
 Nassar AMK, Salim YM, & Malhat FM (2016) Assessment of Pesticide Residues in Human Blood and Effects of Occupational Exposure on Hematological and Hormonal Qualities. Pakistan J Biol Sci. https://doi.org/10.3923/pjbs.2016.95.105.
 Raju KSR, Taneja I, Rashid M, et al (2016) DBS-platform for biomonitoring and toxicokinetics of toxicants: Proof of concept using LC-MS/MS analysis of fipronil and its metabolites in blood. Sci Rep 6:1â€“9. https://doi.org/10.1038/srep22447.
 Roques BB, Lacroix MZ, Puel S, et al (2012) CYP450-Dependent biotransformation of the insecticide fipronil into fipronil sulfone can mediate fipronil-induced thyroid disruption in rats. Toxicol Sci 127:29â€“41. https://doi.org/10.1093/toxsci/kfs094.
 SAS (2016) Statistical Analysis System. Version 9.3.
 Thompson M, Ellison SLR, & Wood R (2002) Harmonized guidelines for single-laboratory validation of methods of analysis (IUPAC Technical Report). Pure Appl Chem 74:835â€“855. https://doi.org/10.1351/pac200274050835.
 Tingle CCD, Rother JA, Dewhurst CF, et al (2003) Fipronil: environmental fate, ecotoxicology, and human health concerns. Rev. Environ. Contam. Toxicol. 176:1â€“66 https://doi.org/10.1007/978-1-4899-7283-5_1.
 Tomasini D, Sampaio MRF, Cardoso L V., et al (2011) Comparison of dispersive liquid-liquid microextraction and the modified QuEChERS method for the determination of fipronil in honey by high performance liquid chromatography with diode-array detection. Anal Methods 3:1893â€“1900. https://doi.org/10.1039/c1ay05221g.
 Tomlin C (2000) The pesticide manual: a world compendium. British Crop Protection Council
 Usui K, Hayashizaki Y, Hashiyada M, & Funayama M (2012) Rapid drug extraction from human whole blood using a modified QuEChERS extraction method. Leg Med 14:286â€“296. https://doi.org/10.1016/j.legalmed.2012.04.008.
 VÄ±Ìlchez JL, Prieto A, Araujo L, & NavalÃ³n A (2001) Determination of fipronil by solid-phase microextraction and gas chromatographyâ€“mass spectrometry. J Chromatogr A 919:215â€“221. https://doi.org/10.1016/S0021-9673(01)00788-9.
 Wang X, MartÃnez MA, Wu Q, et al (2016) Fipronil insecticide toxicology: oxidative stress and metabolism. Crit Rev Toxicol 46:876â€“899. https://doi.org/10.1080/10408444.2016.1223014.