Lipid-free tuna muscle samples are suitable for total mercury analysis

Tropical tunas are largely consumed worldwide, providing major nutritional benefits to humans, but also representing the main exposure methylmercury, a potent neurotoxin that biomagnifies along food webs. The combination of ecological tracers (nitrogen and carbon stable isotopes, ?15N ?13C) mercury concentrations in is scarce yet crucial better characterize influence tuna foraging ecology on bioaccumulation. Given difficulties get modern historical samples, analyses have be done available unique samples. However, ?13C values often analysed lipid-free samples avoid bias related lipid content. While extraction with non-polar solvents known no effect values, its impact still unclear. We used white muscle tissues three tropical species evaluate efficiency repeatability different protocols commonly analysis. Dichloromethane was more efficient than cyclohexane extracting lipids muscle, while automated method appeared as repeatable manual method. Lipid dichloromethane had concentrations. This may result from i) affinity methylmercury proteins flesh, ii) low content iii) nature dichloromethane. Our study suggests usually prepared for research, can equivalently bulk document parallel at global scale.