Table 2.

Comparison of inhibition constants (IC₅₀s) from this study and IC₅₀s reported in literature

	Electric eel		Human
Chemical	IC50 Value	References	Source	IC50 Value	Reference	In vivo concentration	Reference
CPO	0.03	This study	Blood	0.27	This study	≤ 0.06	Eyer et al. (2009)
	0.03	Čolović et al. (2011)	Recombinant enzyme	0.35	Sipes et al. (2013)	≤ 0.02	Heilmair et al. (2008)
	0.01	Jett et al. (1999)	Recombinant enzyme	0.014	Li et al. (2019)
	0.01	Meijer et al. (2014)
PMO	0.07	This study	Blood	1.8	This study
DZO	1.03	This study	Blood	2.5	This study
	0.05	Čolović et al. (2011)	Recombinant enzyme	1.3	Li et al. (2019)
PI	61	This study	Blood	20	This study	≤ 300	Hoffmann et al. (2008)
RI	53	This study	Blood	9.9	This study	≤ 0.34	Lefèvre et al. (2016)
	11	Uysal et al. (2018)	Neocortex	9.1	(Jackisch et al. 2009)	~ 0.1	Hossain et al. (2002)
	11	Tehrani et al. (2019)
	56	(Kratky et al. 2018)
	501	(Imramovsky et al. 2012)
CPF	> 0.35	This study	Blood	> 10	This study	≤ 10	Buratti et al. (2003)
	4.5	Čolović et al. (2011)	Blood	0.12	Das et al. (2006)	≤ 5	Huen et al. (2012)
	0.03	(Assis et al. 2012)	Red blood cells	200	(Ajilore et al. 2018)	≤ 5	Eyer et al. (2009)
PM	> 1.4	This study	Blood	> 30	This study	≤ 50	Santori et al. (2020)
			Recombinant enzyme	Inactive	(Li et al. 2019)
DZN	> 8.5	This study	Blood	> 10	This study	≤ 10	Buratti et al. (2003)
	> 200	Čolović et al. (2011)	Recombinant enzyme	38	Li et al. (2019)
	0.3	Assis et al. (2012)

IC₅₀s for both electric eel and human (average of all donors) are depicted for all compounds tested in this study: chlorpyrifos-oxon (CPO), phosmet-oxon (PMO), diazinon-oxon (DZO), pirimicarb (PI), rivastigmine (RI), chlorpyrifos (CPF), phosmet (PM), diazinon (DZN). For human values, the source of the enzyme is depicted. The values derived in the current study are indicated in italic and all concentrations are in µM. In vivo concentrations depict concentrations as measured or estimated in plasma following human exposure