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The modified QuEChERS method was evaluated for rapid determination of pesticide residues in spinach by gas chromatography-nitrogen phosphorous detector (NPD) and electron capture detector (ECD). Fifty GC-amenable pesticides which were most frequently detected in monitoring were selected in the current study. Matrix-matched calibration was performed. The detector response for all pesticides was linear with determination coefficients higher than 0.995. LODs for most compounds ranged between 0.001 and 0.1 ug/g, and about 90% of the compounds had LODs of less than 0.05 ug/g. LOQs ranged from 0.001 to 0.32 ug/g, which were well below the MRLs permitted for most of pesticides. In the majority of cases, the recoveries (80-120%) and relative standard deviations (RSDs) (less than 20%) were within acceptable levels except for dichlorvos, propamocarb, chlorothalonil, dichlofluanid, cyhalothrin and fenvalerate. Also, this method which is applied to routine samples showed good results when comparing with traditional multi-residue method.

Objectives: This study was performed to provide basic data for the re-establishment of standards (criteria) and analytical methods for hazardous metals in nail enamel.Methods: Ten metals (lead; Pb, arsenic; As, cadminum; Cd, antimony: Sb, cobalt; Co, nikel; Ni, copper; Cu, chromium; Cr, aluminum; Al, and mercury; Hg) were measured in 67 commercial nail enamels containing glitter and/or pearls. The content of hazardous metals (excepting Hg) was determined by using an inductively coupled plasma-optical emission spectrophotometer (ICP-OES) after microwave digestion. Mercury content was measured by a mercury analyzer without any preparation.Results: The detected ranges of the intact samples were as follows: ND -1.756 µg/g for Pb, ND -1.24 µg/g for As, ND for Cd, ND -20.41 µg/g for Sb, ND -12.36 µg/g for Co, ND -7.908 µg/g for Ni, 0.088 -79.27 µg/g for Cu, 0.281 -18.54 µg/g for Cr, 13.78 -3 563 µg/g for Al, and ND -0.044 µg/g for Hg. After centrifugation, the detected ranges of supernatant were as follows: ND -0.435 µg/g for Pb, ND -0.504 µg/g for As, ND for Cd, ND -0.035 µg/g for Sb, ND -13.17 µg/g for Co, ND -0.232 µg/g for Ni, 0.117 -90.07 µg/g for Cu, 0.174 -2.787 µg/g for Cr, and 9.459 -1 565 µg/g for Al. The results of this analysis showed that the levels of heavy metals such as Pb, As, and Sb were much higher in the intact samples than those of supernatant. Conclusion:In the present study, we found that the levels of hazardous metals were significantly different depending on the status of the presence of glitter. Based on the results, we recommend that the product consumer refrain from prolonged application of nail enamel, avoid biting or chewing the nails, and wear gloves during cooking and washing dishes.