Levels and congener pattern of polychlorinated biphenyl and organochlorine pesticide residues in bluefin tuna (Thunnus thynnus) from the Straits of Messina (Sicily, Italy).

The aim of this study is to assess the accumulation of OCs and PCBs in Thunnus thynnus and to elucidate the suitability of this species as a bioindicator for monitoring contaminations of these compounds in the marine ecosystems of the Straits of Messina. This investigation was conducted on fat, liver and muscle samples of 14 T. thynnus collected during April 2004. Quantitative determination of OCs and PCBs in the various samples examined has been carried out using GC-ECD and GC-MS. The results obtained show the presence of low concentrations of p,p'-DDE and PCB congeners (138, 153 and 180) in all fat, liver and muscle samples caught in the Straits of Messina. Concentrations of p,p'-DDE and PCB congeners (138, 153 and 180) in all the samples examined were below MRLs (CE n. 97/41, 1999/65 and 1999/71).

Speciation of inorganic arsenic in alimentary and environmental aqueous samples by using derivative anodic stripping chronopotentiometry (dASCP).

The purpose of this research was to develop a sensitive and accurate chronopotentiometric method at a gold film electrode, to determine trace and ultra trace levels of As(III) and As(V) in alimentary and environmental water systems. As(III) was directly determined in the aqueous matrix at a deposition potential of -300 mV for 180 s and at a constant anodic current of 2.5 microA, without any sample pre-treatment; moreover the chronopotentiometric method did not require a time-consuming de-oxygenation step prior to the analysis. A 3M HCl solution was chosen as the best stripping medium. The direct analysis of As(V) required the application of a high negative over-potential and, thus, measurements were characterized by poor reproducibility; therefore As(V) was determined after reduction to As(III) with KI in a strong hydrochloric acid solution. Under the optimised electrochemical conditions, detection limits of 0.08 microg As(III) l(-1) were achieved and no significant interferences from Cd, Cu, Pb, Zn and organic substances were observed. As(V) was the most abundant species in all the studied environmental and alimentary aqueous matrices. Amongst the beverages, tea and coffee presented the As(V) highest concentration ranges (934-1740 microg l(-1) and 850-1290 microg l(-1), respectively) while bottled mineral water the lowest (<1.61 microg l(-1)); whereas As(III) levels lower than 5.0 microg l(-1) were detected only in wine samples.

Contamination of Italian citrus essential oils: presence of chloroparaffin.

In this study, the contamination by chloroparaffin of Sicilian and Calabrian citrus essential oils, produced in the crop years 1994-1996, was investigated. The analyses were carried out on 102 lemon oils, 98 orange oils, and 96 mandarin oils, using a dual-channel GC-ECD. It was found that 53% of lemon oil, 33% of orange oil, and 38% of mandarin oil samples were contaminated. The mean contamination levels were 7.1 ppm (lemon), 2.5 ppm (orange), and 5.3 ppm (mandarin). The highest concentration of chloroparaffin found was 60 ppm in a lemon oil sample.

Inorganic anions in goat and ovine milk from Calabria (Italy) by suppressed ion chromatography.

Forty-seven samples of milk taken from goat and ovine farms in Calabria (southern Italy) between April and May 2010 were analysed. Analyses were carried out by ion chromatography (ICS 1000; Dionex). For method validation, RSDs (%) on retention times and on peak area were determined by considering a mixture of standard anions at the concentration level of 0.1-30 mg l(-1) for chloride, bromide, nitrite, nitrate, sulfate and phosphate. The higher RSDs were 1.4% and 2.2% for retention times and 2.4% and 3.7% for areas for intra- and inter-day repeatability, respectively. Good linearity was observed in each concentration range, with linear correlation coefficients (R(2)) better than 0.987. The LODs and LOQs were calculated experimentally as signal-to-noise ratios of 3 and 10, respectively. Analysis of the results obtained indicated that phosphates were the most abundant anion (1409-3050 mg l(-1)) followed by chloride (679-2568 mg l(-1)) and sulfates (25-341 mg l(-1)). Nitrates were found to be lower at 146 mg l(-1) (the maximum value observed). The values of anions found in this work are in agreement with those reported in the literature for cow's milk. There are no significant differences between ovine and goat's milk samples. The method used for this analysis of anions combines rapidity with high precision, accuracy and sensitivity; therefore, it is suitable for routine analysis. Moreover, one of the most obvious advantages of this technique is that multiple elements can be determined in one sample with no serial dilutions and the complete analysis can be performed by using only one instrument.

Determination of trace elements in goat and ovine milk from Calabria (Italy) by ICP-AES.

There are many sources of contamination to which milk could be exposed: grazing animals can ingest contaminants present in nature, such as lead in soil, or that have been deposited on grass, resulting from industrial emissions. Another possible route of contamination is represented by feed for animals, which may contain heavy and essential metals. The potential of high-resolution inductively coupled plasma spectrometry was evaluated to quantify reliably various toxic and essential elements (Fe, Zn, Pb, Cr, Ni, Cu, As, Se, Cd) in 47 samples of goat and ovine milk from various farms in Calabria (southern Italy). The results showed that concentrations of cadmium were below the limit of detection. Lead levels were below the maximum limits as set by the EC in almost all samples tested. The highest values were those of Zn followed by Fe, Cu and Se.

Classification of the geographical origin of Italian donkey's milk based on differences in inorganic anions.

The content of chlorides, nitrites, nitrates, phosphates and sulphates was used to classify 45 donkey's milk samples collected from different Italian regions. A method employing ion exchange chromatography with conductivity detector and chemical suppression was used. The quantitative results indicated phosphates (569.4-1304.4 mg kg(-1)) and chlorides (545.9-1757.9 mg kg(-1)) as being the most abundant anions, followed by sulphates (109.5-200.7 mg kg(-1)). The concentrations of nitrites and nitrates were found to be lower at 5.6 and 5.5 mg kg(-1) respectively. The data set was subdivided into three groups according to the region of origin of milk, and was statistically evaluated by analysis of variance (ANOVA). Concentrations of chlorides and nitrites showed a significant difference among farms (p < 0.001). In a first discriminant analysis procedure, functions based on linear combinations of the log(e)-transformed element concentrations of anions were generated to classify donkey's milk samples from different regions. In an alternative approach, a three-step discriminant analysis procedure to classify a milk sample was tested. The results obtained led to a correct classification of donkey's milk samples based on their anions content with 91-98% of the samples being correctly classified. The procedure proved to be very simple, so it could be used as an evaluation method for the traceability of donkey's milk, thus defending this unique product against fraud or commercial disputes.

Influence of roasting and different brewing processes on the ochratoxin A content in coffee determined by high-performance liquid chromatography-fluorescence detection (HPLC-FLD).

A rapid and reliable procedure has been developed for the determination of ochratoxin A (OTA) in green and roasted coffee. The method consists of extraction of the sample with methanol-5% aqueous sodium hydrogen carbonate/1% PEG8000 (20:80), followed by immunoaffinity column (IAC) clean-up and, finally, high-performance liquid chromatography (HPLC) determination with fluorimetric detection. Mean recoveries for green and roasted coffee spiked at different levels ranging from 94 and 105% were obtained. The limit of determination (S/N = 3) was 0.032 ng g(-1) and the precision (within-laboratory relative standard deviation) was 6%. The method described has been used to assess the influence of roasting and different brewing processes on OTA content in commercial lots of green and roasted coffee. The results provided evidence that roasting led to a significant drop on OTA levels (65-100%). Also, the way coffee is prepared affects the OTA content: brewing using a Moka Express (Italian coffee) led to a significant reduction of OTA concentration (50-75%) since hot water stays in contact with coffee for a short time. On the contrary, Turkish coffee-making (infusion for about 10 min) cause poor reduction in OTA.

Organochlorine pesticides and polychlorinated biphenyl residues in reared and wild Dicentrarchus labrax from the Mediterranean Sea (Sicily, Italy).

The aim of this research was to compare the levels of organochlorine pesticides and PCBs in samples of Dicentrarchus labrax living in the Straits of Messina with samples cultivated in cages in the Mediterranean Sea. Muscles and liver tissues sampled over the months, within the same year, were analyzed. The quantitative determination of the organochlorine compounds was performed by GC-ECD and confirmed with GC-MS. The results showed that the concentrations of DDTs in muscles and livers as such of reared sea bass were in the range 0.2-1.3 microg/kg and 9.6 -48.4 microg/kg, respectively. In wild fish the concentrations of DDTs were very much lower: 0.1 microg/kg in muscles, 5.1-9.0 microg/kg in livers. Total PCBs levels were higher in cultivated sea bass than in wild fish; the concentration ranges were 5.3-59.7 microg/kg and 74.4-267.4 microg/kg in muscle and liver of reared samples, respectively, and 1.1-1.5 microg/kg and 63.2-109.4 microg/kg in muscle and liver of wild samples, respectively.

Determination of copper, zinc, selenium, lead and cadmium in potatoes (Solanum tuberosum L.) using potentiometric stripping methods.

Potentiometric stripping analysis was used to determine simultaneously the content of zinc(II), cadmium(II), lead(II) and copper(II) in potatoes, whereas the concentration of selenium was determined by cathodic stripping potentiometric analysis. Metal cations were extracted from potatoes by hydrogen peroxide/hydrochloric acid treatments. The relative standard deviation of the methods ranged from 2.3 to 4.1% and the detection limits were lower than 2.5 microg kg(-1). The results obtained with the proposed methods were compared with those obtained with graphite furnace atomic absorption spectroscopy, a common method for determining metals. The results of the two methods agreed to within 6.1%. Twelve samples of yellow flesh potatoes from different cultivars were analysed. Of all the metals determined, Cu and Zn were the most abundant with concentrations between 0.5 and 4.6 mg kg(-1). Selenium was only found in three samples in very low amounts (<0.1 mg kg(-1)), whilst Pb and Cd concentrations were in the range 0.01-0.27 mg kg(-1).