Dailos González-Weller

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.

Dietary intake of barium, bismuth, chromium, lithium, and strontium in a Spanish population (Canary Islands, Spain)

The aim of this study was to analyze barium, bismuth, chromium, lithium, and strontium contents in food and beverages consumed by the population of the Canary Islands (Spain) as well as determine dietary intake of these metals in the archipelago as a whole and in its individual islands. To this end, 440 samples were analyzed by ICP-OES and GFAAS. Barium concentrations ranged from 5.210 ± 2.117 mg/kg in nuts to 0.035 ± 0.043 mg/L in water. Viscera exhibited the highest levels of bismuth (38.07 ± 36.80 mg/kg). The cold meat and sausages group stood out for its high chromium concentrations (0.494 ± 0.257 mg/kg). The highest concentration of lithium and strontium came out in nuts (8.761 ± 5.368 mg/kg and 9.759 ± 5.181 mg/kg, respectively). The total intakes of barium, bismuth, chromium, lithium, and strontium were 0.685, 1.274, 0.087, 3.674, and 1.923 mg/day, respectively. Cereals turned out to contribute most to the dietary intake of barium, bismuth, chromium, and lithium in the Canary Islands, while fruit contributes most to the strontium intake. We also performed a metal intake study by age and sex of the population and compared the outcome with data from other regions, both national and international.

Metals in wheat flour: comparative study and safety control

Cereal industry and its derived products have a big economic and social importance worldwide. Therefore, as wheat flour is a commodity for all bread and bakery industry, it is safety is of high nutrition and toxicological interest. In this investigation we intend to study and determine the content of twelve metals in 50 samples of wheat flour coming from a wheat flour industry. Macro elements sodium, potassium magnesium and calcium, micro elements manganese, iron, copper, zinc, chrome and nickel as well as toxic trace elements cadmium and lead have been analysed. The estimated diary intake of each metal and their contribution in percentage terms to the RDI (macro and micro elements) and to the PTWI (toxic elements) has been determined. Contribution of Cd and Pb to the PTWI was very low, a fact that shows safety in this wheat flour concerning toxic metals.

Content of trace metals (iron, zinc, manganese, chromium, copper, nickel) in canned variegated scallops (Chlamys varia)

This article presents the results obtained through a study of the concentration of trace metals (iron, zinc, manganese, chromium, copper, nickel) in some conserves of variegated scallops (Chlamys varia, Bivalvia, Mollusca). A total of 300 samples of seven different commercial brands (named A, B, D, H, J, L and M) and one processing type, ‘scallop sauce’, were analysed. Samples were collected weekly in a large shopping centre in Santa Cruz de Tenerife during a 12-month period. Variegated scallops have considerable concentrations of zinc, cupper and manganese, so that their dietary intake constitutes an important source of these metals. However, they have low concentrations of chrome and nickel, and the levels of iron are similar to those found in other bivalve molluscs.

Trace elements and toxic metals in intensively produced tomatoes (lycopersicom esculentum)

INTRODUCTION Tomato is considered a healthy food due to its high content in lycopene and other health-promoting natural compounds. Tomatoes have, undoubtedly, assumed the status of a food with functional properties, considering the epidemiological evidence of reducing the risk of certain types of cancers. OBJECTIVE Samples of tomatoes from Morocco were analyzed for the mineral composition. METHODS 94 tomato samples from Morocco were analyzed. Flame Atomic Absorption Spectrophotometry (FAAS) was used to determine essential elements (Copper (Cu), iron (Fe), manganese (Mn) and zinc (Zn)) and Atomic Absorption Spectrophotometry with Graphite Furnace (GAAS) was used to analyzed cadmium (Cd) and lead (Pb). RESULTS The mean concentrations were 0.17 mg/kg, 0.73 mg/kg, 0.20 mg/kg, 0.44 mg/kg, 7.58 μg/kg and 15.8 μg/kg for Cu, Fe, Mn, Zn, Cd and Pb, respectively. The highest contribution to the intakes was observed for Cu (0.67% for adults) while that Zn showed the lowest contribution (0.14% for adult males and 0.20% for adult females). CONCLUSIONS Tomatoes are a good source of essential elements for the diet, mainly iron and zinc. Tomatoes consumption does not significantly affect the intake of heavy metals.

Heavy and trace metal concentrations in three rockpool shrimp species (Palaemon elegans, Palaemon adspersus and Palaemon serratus) from Tenerife (Canary Islands)

Trace metal concentrations (Fe, Cu, Co, Zn, Ni and V) were investigated in three rockpool shrimp species (Palaemon elegans, Palaemon adspersus and Palaemon serratus) from six littoral sampling sites (polluted and non-polluted) of Tenerife in the Canary Islands (Central Eastern Atlantic), Spain. Sex ratio for all three species has been determined: females predominate over males in all species and significant differences in total length and cephalothorax length was detected between sexes, being females larger than males. By other side, concentrations of trace metals were determined in whole specimens. Higher mean values for every metal were observed in P. adspersus. In males, higher values were observed in P. elegans and P. serratus, whereas in P. adspersus, mean values are higher in females. Finally, mean concentrations of trace metals studied were higher, in general terms, in the two clearly polluted stations: Santa Cruz of Tenerife commercial harbour and its fishery dock dependency.

Accumulation of toxic metals (Pb and Cd) in the sea urchin Diadema aff. antillarum Philippi, 1845, in an oceanic island (Tenerife, Canary Islands)

This document shows the results obtained from a study on the concentration of toxic heavy metals in the internal tissue and exoskeleton of sea urchins, collected from their natural habitat. The levels of lead and cadmium were measured by Graphite Furnace Atomic Absorption Spectrometry. The mean concentrations of lead and cadmium in the internal tissue were 304.04 and 260.54 μg/kg respectively, whereas in the shell they were 185.02 and 142.48 μg/kg. We also performed a statistical analysis of the differences in the distribution of metals between their exoskeleton and their internal content, a correlation study of the metal content in internal tissue and shell and sampling areas, and a correlation study between the metal content and sample size. Since the sea urchin Diadema antillarum presents a wide range of variation in metal content, this study suggests that this species is an excellent bioindicator of heavy metal contamination.

Dietary Intake of Metals from Fresh Cage-Reared Hens’ Eggs in Tenerife, Canary Islands

The concentrations of 20 metals (Na, K, Ca, Mg, V, Mn, Fe, Cu, Zn, Cr, Mo, Co, B, Ba, Sr, Ni, Si, Al, Pb, and Cd) in cage-reared hens’ eggs have been determined in this study using inductively coupled plasma atomic emission spectroscopy (ICP-OES). There were significant differences in the metal content depending on the edible part of the egg, with the yolk having the greater concentrations of metals. The daily consumption of eggs (24.3 g/person/day for children and 31.2 g/person/day for adults) contributes to the intake of trace metals, notably Fe (3.8% children, 3.2% women, and 6.5% men) and Zn (4.5% children, 6.6% women, and 4.9% men). In addition, the consumption of eggs does not imply a high contribution of toxic metals.