Arturo Hardisson

Mineral composition of the banana (Musa acuminata) from the island of Tenerife

The content of major (Na, K, Ca, Mg and P) and minor elements (Fe, Cu, Zn, Mn and B) in bananas consumed on the island of Tenerife, Canary Islands, has been determined. Significant differences were observed in the mineral contents of the banana samples, with higher K, Mg, P, Fe, Cu, Zn and B levels in the banana grown in north Tenerife and a higher Ca content in the banana originating in the south of the island. Differences between these mineral contents and the fruit reported in the literature have been established and a comparison has been carried out with diverse food composition tables. The banana is shown to contribute to the recommended daily requirements of K, Mg, Cu and B.

Lead and cadmium in meat and meat products consumed by the population in Tenerife Island, Spain

The aim of this study was to determine the levels of lead and cadmium in chicken, pork, beef, lamb and turkey samples (both meat and meat products), collected in the island of Tenerife (Spain). Lead and cadmium were measured by graphite furnace atomic absorption spectrometry (GFAAS). Mean concentrations of lead and cadmium were 6.94 and 1.68 µg kg−1 in chicken meat, 5.00 and 5.49 µg kg−1 in pork meat, 1.91 and 1.90 µg kg−1 in beef meat and 1.35 and 1.22 µg kg−1 in lamb meat samples, respectively. Lead was below the detection limit in turkey samples and mean cadmium concentration was 5.49 µg kg−1. Mean concentrations of lead and cadmium in chicken meat product samples were 3.16 and 4.15 µg kg−1, 4.89 and 6.50 µg kg−1 in pork meat product, 6.72 and 4.76 µg kg−1 in beef meat product and 9.12 and 5.98 µg kg−1 in turkey meat product samples, respectively. The percentage contribution of the two considered metals to provisional tolerable weekly intake (PTWI) was calculated for meat and meat products. Statistically significant differences were found for lead content in meats between the chicken and pork groups and the turkey and beef groups, whereas for cadmium concentrations in meats, significant differences were observed between the turkey and chicken, beef and lamb groups. In meat products, no clear differences were observed for lead and cadmium between the various groups.

Dietary Intake of Aluminum in a Spanish Population (Canary Islands)

The aim of this study was to analyze the aluminum content in foods and beverages most commonly consumed by the Canary Island population to determine the dietary intake of this metal throughout the Canary Islands as a whole and in each of the seven islands (Gran Canaria, Lanzarote, Fuerteventura, Tenerife, La Palma, La Gomera, and El Hierro). Four hundred and forty samples were analyzed by ICP-OES. Estimated total intake of aluminum for the Canary population was 10.171 mg/day, slightly higher than the provisional tolerable weekly intake (PTWI; 10 mg/day for a person weighing 70 kg). Aluminum intake by age and sex of the Canary Island population was also determined and compared values from other populations, both national and international.

Differentiation of two Canary DO red wines according to their metal content from inductively coupled plasma optical emission spectrometry and graphite furnace atomic absorption spectrometry by using Probabilistic Neural Networks

The metal content of 54 commercialized wines (30 samples from Tacoronte-Acentejo DO (class T) and 24 Valle de la Orotava DO (class O) wines) was performed by ICP-OES (Al, Ba, Cu, Fe, Mn, Sr, Zn, Ca, K, Na and Mg) and GF-AAS (Ni and Pb). Wine samples were processed by dry ashing followed by solution with 5% nitric acid. Metals were considered as suitable descriptors to differentiate between T and O classes. Supervised learning pattern recognition procedures were applied. Linear discriminant analysis (LDA) led to good results up to about 90% of correct classification. In order to improve the results, another kind of algorithms able to model non-linear separation between classes was considered: Probabilistic Neural Networks. Accordingly, excellent results were obtained, leading to sensitivities and specificities higher than 95% for the two classes.

Concentrations of metals in vegetable edible oils

Abstract Concentrations of Na, K, Ca, Mg, Cu, Zn and Fe as well as the indices of acidity and peroxides have been determined in several Spanish edible oils. For Cu and Fe, respectively, 18·3% and 2·8% of the samples showed higher values than the maximum permitted by FAO/WHO. However, there were no samples that exceeded the maximum values established by the Spanish directorate for these two metals. Maximum values for the indices of acidity and peroxides established by the Spanish directorate were exceeded in 17% and 21% of the samples overall. Olive oil had a higher number of samples that exceed the maximum values of the Spanish directorate than other analysed oils. The ratio Na K was always higher than unity, which means that the oils had been subjected to a refinement process. Strong correlations between Na and K and between Ca and Mg were found in all the types of oil studied. Also, moderate correlations between the acidity index and the concentration of Fe, and between the indices of acidity and peroxide, have been observed.

Daily dietary intake of iron, copper, zinc and manganese in a Spanish population

To evaluate the daily dietary intake of essential metals in the Canary Islands, the iron, copper, zinc and manganese contents in 420 food and drink samples collected in local markets were analysed by inductively coupled plasma-atomic emission spectrometry (ICP-AES). The estimated daily dietary intakes of iron, copper, zinc and manganese are 13.161 mg/day, 2.098 mg/day, 8.954 mg/day and 2.372 mg/day, respectively. The iron dietary intake was found to be below the recommendations fixed for adult women, while the copper and manganese dietary intakes fulfilled the Recommended Dietary Allowances. The mean daily intake of zinc was below the Recommended Dietary Allowance. Cereals were found to be the food group that contributed most to the intake of these metals. While the island of El-Hierro presented iron, copper, zinc and manganese mean intakes over the estimated intakes for the whole archipelago, Fuerteventura island showed the lowest intakes. Tenerife and Fuerteventura showed the lowest iron intakes, being below the recommendations.

Levels of Metals in Canned Meat Products: Intermetallic Correlations

The analytical control of heavy metals in food is particularly important, since these pollutants are notably cumulative in nature and, therefore, can be toxic to humans. Their determination in foods of animal origin is of interest. In this study analyses of seven heavy metals in semipreserved ham and shoulder pork, preserved lunch pork and pork liver paste were performed to determine the possible influence of the container itself on the levels of metals in such products. Not only were the toxic elements cadmium and lead studied, but also copper, zinc, iron, nickel and manganese which, although not essentially toxic, could, in high concentration, cause public health hazards or a decrease in the organoleptic quality of the canned product, with resultant economic effect.

Total dietary intake of mercury in the Canary Islands, Spain

Estimating the risk associated with dietary intake of heavy metals by consumers is a vital and integral part of regulatory processes. The assessment of exposure to mercury shown in this paper has been performed by means of a study on the whole diet. Total mercury (Hg) levels were determined by cold vapour atomic absorption spectrometry (AAS) in 420 samples of regularly consumed food and drink. The total Hg concentrations measured in the different groups of food ranged from non-detectable to 119 µg kg−1 w/w. The fish group had the highest concentrations of total Hg. All groups of food with regulated Hg content showed levels that were lower than the legally set values. The food consumption data used in the analysis were taken from the latest nutritional survey made in the Canary Islands, Spain. The estimated total Hg intake of local population (5.7 µg/person day−1) did not exceed the provisional tolerable weekly intake (PTWI) limit of 0.3 mg week−1 of total mercury (43 µg/person day−1) fixed by the Joint Food and Agricultural Organization/World Health Organization (FAO/WHO) Expert Committee on Food Additives. Fishery products contributed 96% of the total Hg intake. The mean Hg intake for each island in this archipelago, formed by seven, has also been calculated. Fuerteventura, Lanzarote and El Hierro are the islands with the highest level of Hg intake (7.0, 7,0 and 6.1 µg/person day−1, respectively). La Palma Island, due to its low fish consumption, had the lowest level of Hg intake (4.5 µg/person day−1), followed by La Gomera (5.4 µg/person day−1), Tenerife (5.5 µg/person day−1) and Gran Canaria (5.6 µg/person day−1). A comparison has been made of the results obtained in this study with those found for other national and international communities.

Correlations between lead, cadmium, copper, zinc, and iron concentrations in frozen tuna fish.

The presence of metallic pollutants in marine ecosystems has promoted wide research plans in order to evaluate pollution levels in marine organisms. However, little is known concerning environmental and physiological processes that regulate the concentration of trace metals in marine organisms. Even though the toxicity of lead and cadmium is well established, copper, zinc and iron are considered as essential elements for mammals. Little is known about heavy metals, other than mercury, concentrations in fresh and frozen tuna fish. Fifty samples obtained at the entrance of a canning factory in Santa Cruz de Tenerife (Canary Islands), were analyzed by atomic absorption spectrophotometry. Results were treated by applying the Statistical Package for the Social Sciences compiled and linked in the software of a Digital VAX/VMS 11/780 computer.

Content of sulphite in frozen prawns and shrimps

Abstract The contents of total sulphite in frozen prawns and shrimps were determined by the Monier–Williams procedure. The use of sulphites could be breaching legislative limits since the residues in the edible parts of some frozen prawns and shrimps samples were found to be higher than 150 mg SO 2 per kg (maximum concentration admitted in the edible parts for these fresh and frozen products according to the current legislation). The non-edible parts presented much higher concentrations.