Based on the detected content of analysed elements it can be concluded that nuts may be a good additional source of minerals as micronutrients.

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This study aimed to optimize and validate the inductively coupled plasma optical emission spectrometric method (ICP OES) for the simultaneous determination of eleven potentially toxic elements (Al, Cd, Cr, Co, Cu, Ni, Pb, Fe, Sb, Mn, and Zn) in lipstick samples. The method was evaluated by applying the standard addition method. The recoveries for all elements in lipsticks were between 90% and 110%, except for Cd and Pb they were <90% and >110%, respectively. The health risk assessment was determined by calculating the average daily intake (ADD), hazard quotient (HQ), and hazard index (HI). The highest mean value for ADD was for Fe (4.8 × 10-1 mg kg-1 day-1), and the lowest was for Co (9.3 × 10-6 mg kg-1 day-1). There was no significant toxic health risk for any of the elements (HQ < 1), except for Fe (HQ < 3) which indicates a potential health risk. Based on PCA, all potentially toxic elements have been classified in the three groups. The first group includes Fe, the second includes Al, and all other elements belong to the third group. The cluster analysis of the elements provided the identical grouping that was obtained on the basis of PCA. Two separate clusters were obtained when cluster analysis was applied to the analyzed samples. The first cluster contained the only sample that was brown. The second cluster was divided into two sub-clusters. The first sub-cluster included the samples belonging to category I regarding the price, while the second sub-cluster included the samples belonging to category II and III regarding the price.

The new kinetically-based spectrophotometric method for the determination of microquantities of ampicillin is proposed in the present paper. Ampicillin degradation in strong alkaline medium was applied for the method development. The reaction rate was monitored at 265 nm. A differential variation of the tangent method was used to process the kinetic data. The method is valid over the 3.49-55.84 µg/mL ampicillin concentration interval with relative standard deviation (RSD) range 7.79-3.20%. The calculated detection limit was determined at 2.58 µg/mL based on the 3.3S0 criterion. The interference effects of some metal ions, anions, amino acids and other molecules were investigated in order to assess the method selectivity. The method was successfully applied to determining the content of ampicillin in commercial pharmaceutical preparations and human urine. The obtained results were in good correlation with the HPLC method results. The newly developed method is simple, inexpensive and efficient for the analysis of a large number of samples at room temperature in a short time.

In the present paper, multi-element characterisation of 26 bagged teas was carried out using inductively-coupled plasma atomic emission spectrometry. Na, K, Ca and Mg were the metals with major contents. Among the essential elements, Fe and Zn were the most abundant, followed by Se, Cu, Mo and Cr. The tea bag samples also contained significant contents of Mn and Al. The chemometric techniques of linear correlation analysis, principal component analysis (PCA) and cluster analysis (CA) were used for differentiation of the tea bag samples according to their metal content. The samples analysed were classified into four groups by PCA and CA. The first group includes hibiscus, nettle, mint, rtanj tea, thyme, bearberry and sage. Green and black teas are in the second group. The third group contains strawberry, lime, pineapple, pomegranate, elder, blueberry, milfoil, apricot and chamomile. Exotic fruits, sweet cherry, forest fruits, apple, St John’s wort, rose hips, cherry and raspberry are in the fourth group.

BACKGROUND: Pesticides are potentially toxic to humans and can produce both acute and chronic health effects, depending on the quantity and the ways in which a person is exposed. Exposure to pesticides can cause serious health problems. Infants and young children are particularly sensitive to these contaminants because their brains and organ systems are not fully developed. For this reason, it is important to determine the quantities of pesticides in baby food. RESULTS:The aim of this study was to develop a kinetic-spectrophotometric method for atrazine determination and to apply it to determine pesticide in baby-food samples, using solid-phase extraction (SPE) followed by the kinetic-spectrophotometric method and the high-performance liquid chromatography (HPLC) method. This method is based on the inhibition effect of atrazine (the oxidation of sulfanilic acid (SA) by hydrogen peroxide in the alkaline medium in the presence of the Co 2+ ion). Under the experimental conditions used, atrazine showed a linear dynamic range of 0.5 to 5.0 g mL −1 , and from 5.0 to 70.00 g mL −1 with relative standard deviations (RSD) from 1.91% to 9.41%. The limit of detection and the limit of quantification were 0.074 and 0.225 g mL −1 , respectively. The kinetic method was successfully applied to determine the atrazine concentration in spiked samples after SPE of samples. High-performance liquid chromatography was used to verify the results. CONCLUSION: The proposed method is highly sensitive, simple, easy, requires cheap reagents, and leads to good recovery levels. It is linear, precise, and accurate. It can be used successfully for the routine analysis of atrazine in infant formulae and cereal-based food samples. A chromatographic analytical-reagent-grade solvent, methanol with a purity of ≥ 99.9%, supplied by Baker (UK), was used for atrazine elution. The solvents, acetone ((CH 3 ) 2 CO) and acetonitrile (ACN), were super-purity solvents obtained from Baker. A J Sci Food Agric 2019; 99: 5424-5431

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The purpose of this paper is to present a new kinetic-spectrophotometric method which involve inexpensive equipment and which can be applied by all analyst who have to determine difenzoquate methyl sulfate (DFQ) residues in citruses and baby juices. The method is based on the inhibited effect of DFQ on the oxidation of sulfanile acid (SA) by hydrogen peroxide in phosphate buffer in presence Cu(II) ion. The reaction was monitored spectrophotometrically by measuring the increase in absorbance of the reaction product at 370 nm. The proposed inhibited method permits determination of DFQ over the range 0.36 to 1.80 mg/mL and 1.80 to 7.20 mg/mL, with quantification limit of 0.184 mg/mL. The relative standard deviations are 0.73-2.90% for the concentration interval of DFQ 1.80-0.36 mg/mL. The method was successfully applied to determination of DFQ residues in citruses and baby juices. The HPLC method is used to verify the results. The results obtained for the same samples by the two methods are quite comparable.