Arturo Hardisson de la Torre

Effect of a bacteriocin produced by Pediococcus acidilactici against Listeria monocytogenes and Clostridium perfringens on Spanish raw meat

The inhibitory effect of a bacteriocin, produced by Pediococcus acidilactici, against Listeria monocytogenes and Clostridium perfringens on Spanish raw meat surface, was evaluated by in situ assays. Samples were incubated with the bacteriocin and then with a culture of the pathogenic bacteria. The treatment with 500, 1000 or 5000 bacteriocin units/ml (BU/ml) reduced the counts of L. monocytogenes after storage at 15°C during 72h by 1, 2 or 3 log cycles and with 1000 or 5000 BU/ml after storage at 4°C during 21 days by 2.5 or 3.5 log cycles, respectively, compared to the control. With C. perfringens a bacteriostatic effect could be observed.

Boron, sulphate, chloride and phosphate contents in musts and wines of the Tacoronte-Acentejo D.O.C. region (Canary Islands)

The concentrations of sulphates, chlorides, boron and phosphorus in musts and wines from the Tacoronte-Acentejo region in Tenerife are studied. The concentrations of these anions in must and wine vary according to the winemaking method and storage vessels and other factors. Concentrations in Tenerife wines fell within the following intervals (-x ±s) from mean value —standard deviation to mean value + standard deviation: 15.9-30.7 mg litre -1 H 3 BO 3 ; 443-827 mg litre -1 K 2 SO 4 ; 230-436 mg litre -1 NaCl; and 261^51 mg litre -1 P 2 O 5 . The mean values were, respectively, 23.3 mg litre -1 H 3 BO 3 ; 635 mg litre -1 K 2 SO 4 ; 333 mg litre -1 NaCl; and 356 mg litre -1 P 2 O 5 . In the case of boron, no statistically significant differences were observed between one year and another or between young and old wines. Sulphate levels were found to be well below the legal limits, although the storage vessel was seen to play a major role, with levels higher in the wines made in cement receptacles and stored in wooden casks. Chloride concentrations were in line with those reported in the literature. As regards phosphates, there was a direct correlation between sugars and must density, indicating that concentration is largely dependent on the degree of grape maturity.

Heavy metals in cigarettes for sale in Spain

The aim of the present study was to determine the concentrations of eight metals (Al, Cd, Co, Cr, Mn, Ni, Pb, Sr) in 33 cigarette brands for sale in Spain. Samples were analysed by Inductively Coupled Plasma Optical Emission Spectrometry (ICP-OES). Mean values obtained were 428 µg Al/g, 0.810 µg Cd/g, 0.558 µg Co/g, 1.442 µg Cr/g, 112.026 µg Mn/g, 2.238 µg Ni/g, 0.602 µg Pb/g and 82.206 µg Sr/g. Statistically significant differences were observed with respect to concentrations of Co (0.004), Cr (0.045), Mn (0.005) and Sr (0.005) between black and blond tobacco and between levels of Mn (0.027) among manufacturers. Considering a Cd inhalation rate of 10% and a Cd absorption rate of 50%, absorption of Cd for smokers of 30 cigarettes/day was estimated at 0.75 µg Cd/day. An inhalation rate of 2-6% and an absorption rate of 86% were considered for Pb, Pb absorption in smokers of 30 cigarettes/day was therefore 0.18-0.54 μg/day. In view of the significant toxic effects of these metals, quantification and control of their concentrations in this drug are of the utmost importance.

EL AGUA DE CONSUMO COMO FUENTE DE EXPOSICIÓN CRÓNICA A FLUORURO EN TENERIFE; EVALUACIÓN DEL RIESGO

INTRODUCTION drinking water is the main source of fluoride exposure for the population. According to the Spanish Law RD 140/2003, the fluoride content in drinking water should not exceed the parametric value of 1.5 mg/L. Historically, certain drinking waters in the island of Tenerife have exceeded this value due to the geological/volcanic characteristics of the Canary Islands. Fluoride (F) plays an important role in the prevention of dental caries (tooth decay). However, long exposure to concentrations above 1.5 mg/L in drinking water can cause disorders such as dental fluorosis. OBJECTIVES To determine the amount of fluoride in the tap waters of the 11 municipalities in the north of the island of Tenerife that, at the time of the study, exceeded the parametric value for fluoride set by the Spanish legislation and to toxicologically estimate and evaluate the fluoride daily intakes from water considering the RDI (Recommended Daily Intake) established in Spain for different population groups. METHOD 44 samples of tap water collected in the 11 municipalities in the study were analyzed using the fluoride potentiometric determination with an ion selective electrode. RESULTS 9 of the 11 municipalities presented mean fluoride concentrations in their tap water that exceeded the parametric value set by the Spanish legislation (1.5 mg/L). Considering an average daily water consumption of 2 L, the recommended daily intake (RDI) for women (3mg F/day) is exceeded in 9 of the 11 municipalities and the RDI for men (4 mg F/day) is exceeded in 5 of the 11 municipalities. Considering a daily water consumption of 1.5 L, the RDI for children of 2-3 years (0.7 mg/day) is clearly exceeded in all municipalities. CONCLUSIONS The results show the existing public health problem on the island of Tenerife and justify the tap water consumption restrictions put in force by the Public Health Authorities of the Canary Islands at the time of the study. Children are the most exposed population group to the risks of fluoride because its RDI is lower.