Ethoxyquin (EQ) is a common antioxidant which is widely used in animal feed. But the supplement of EQ in animal feed may lead to the residues of EQ and its major oxidation products: ethoxyquin quinone imine (EQI) and ethoxyquin dimer (EQDM) in animal tissue. Thus, it would pose potential health hazards to consumers. However, the method for the simultaneous determination of EQ, EQI and EQDM in animal tissues is currently not available, and the accumulation extend of these chemicals in animal tissues after EQ administration remains to be evaluated. A gas chromatography-tandem mass spectrometry method was successfully developed for the simultaneous determination of EQ, EQI and EQDM in swine tissues. The quantitative limits of EQ, EQI and EQDM can achieve to 0.5, 5.0 and 5.0 μg/kg in swine tissues, respectively. The spiked-recovery ratios of the three analytes (5–2000 μg/kg) were in the range of 64.7%–100.7% with relative standard deviations below 11.6%. Moreover, the utilization of this method for the analysis of actual swine tissue samples revealed that the application of commercial EQ additive in swine diet would produce the residues of all the three chemicals (EQ, EQI and EQDM) in fat, kidney, liver and muscle. The assay accuracy and precision of this GC-MS/MS method can meet the requirement of quantitative analysis. Meanwhile, the safety of EQ as a feed additive should be seriously considered with regard to food safety concerns since the oxidation product of EQ may have potential carcinogenicity.

中文翻译：

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采用气相色谱-串联质谱法分析猪组织中的乙氧基喹啉及其氧化产物，以评估乙氧基喹啉及其代谢物向动物组织的转移


乙氧基喹啉（EQ）是一种常见的抗氧化剂，广泛用于动物饲料中。但在动物饲料中添加EQ可能会导致EQ及其主要氧化产物：乙氧基醌醌亚胺（EQI）和乙氧基醌二聚体（EQDM）在动物组织中残留。因此，它会给消费者带来潜在的健康危害。然而，目前尚无同时测定动物组织中EQ、EQI和EQDM的方法，且EQ施用后这些化学物质在动物组织中的累积程度仍有待评估。成功建立了同时测定猪组织中EQ、EQI和EQDM的气相色谱-串联质谱方法。 EQ、EQI和EQDM在猪组织中的定量限分别可达0.5、5.0和5.0 μg/kg。三种分析物 (5–2000 μg/kg) 的加标回收率在 64.7%–100.7% 范围内，相对标准偏差低于 11.6%。此外，利用该方法对实际猪组织样本进行分析表明，在猪日粮中使用商业EQ添加剂会在脂肪、肾脏、肝脏和肌肉中产生所有三种化学物质（EQ、EQI和EQDM）的残留。 。该GC-MS/MS方法的测定准确度和精密度能够满足定量分析的要求。同时，EQ作为饲料添加剂的安全性也应从食品安全角度认真考虑，因为EQ的氧化产物可能具有潜在的致癌性。