[LC-MS/MS analysis of herbicide residues in waters from Navarre]

BACKGROUND

The aim of the study was to obtain information on the residues of herbicides (imazametabenz, simazine, isoproturon, clortoluron, metribuzine, atrazine, cianazine, terbutrin, propanil, terbutilazine, alachlor and pendimetalin) present in water proceeding from Navarre.

MATERIAL AND METHODS

A total of 465 samples of water were taken: 378 were taken from 141 water supplies; the remaining 87 proceeded from fountains, springs and borings in agricultural areas in the south of Navarre. The technique employed was LC-MS/MS.

RESULTS

Herbicide residues were detected in 33% of the water supplies, and their concentration exceeded the normative limit in 8% of them. Herbicide residues were found in 86% of the samples from wells and fountains of the agricultural areas of the south of Navarre. The number of water supplies with herbicide residues increased from north to south. However, the percentage of water supplies in which the concentration of herbicides exceeded the limits was greater in the centre of Navarre than in the north and south. Imazametabenz was the herbicide most detected in the samples from the northern, central and southern areas. Atrazine, terbutilazine and imazametabenz were most detected in the samples of the southern area.

CONCLUSIONS

The differences amongst the three areas of Navarre can be explained as being due to the different agricultural practices of each area. Concentrations of herbicides exceeding the normative limits were not detected in any of the water samples proceeding from the larger towns of Navarre.

Gas chromatographic determination of organochlorine pesticides in cow milk

A gas chromatographic method of use in determining the following organochlorine pesticides in cow milk has been adapted and validated: alpha-hexachlorocyclohexane (alpha-HCH), beta-HCH, lindane, delta-HCH, hexachlorobenzene, aldrin, heptachlor, heptachlor epoxide, mirex, 2,4-dichlorodiphenyltrichloroethane (2,4-DDT), 4,4-DDT, 2,4-dichlorodiphenyldichloroethane (2,4-DDD), 4,4-DDD, 2,4-dichlorodiphenylethane (2,4-DDE) and 4,4-DDE. The method studied consists of three steps: the extraction of fat by centrifugation, mixing with anhydrous sodium sulfate, and transfer to a glass column and elution with hexane; purification of the extract via concentrated sulfuric acid treatment; and determination of the organochlorine pesticides by gas chromatography equipped with an electron capture detector. The analytical parameters determined to estimate the quality of the method yielded the following results: correlation coefficients (r) of the calibration curves were greater than 0.996, the variation coefficients of the response factors were less than 4.90%--with the exception of aldrin (5.53%) and lindane (5.75%)--the relative standard deviation of the slope (Sm rel) being < or =1.52%. Zero was included in the confidence limits of the independent term range. The method repeatability and reproducibility values were < or =4.73% and < or =5.79%, respectively. The recovery values of the pesticides analyzed were in the range of 81.92% (alpha-HCH) to 105.49% (4,4-DDT), except in the case of aldrin and heptachlor epoxide, which yielded recovery values of under 40%. The quantification limits of the method were < or =1 ng/g, with the exception of mirex (5 ng/g).

Residuos de contaminantes orgánicos de diferentes orígenes en Navarra

An analysis was made of residues of polychlorobyphenyls and trihalomethanes through GC-ECD and of herbicides through HPLC-PAD in samples proceeding from Navarra. Polychlorobyphenyls were detected (0.30 +/- 0.05 and 0.11 +/- 0.05 microg/l) in two of the 106 water samples analysed. Sixty-six food samples were analysed, and polychlorobyphenyls were only found in 8 samples of trout (dissimilar to dioxins: 21-194 microg/kg of fat; similar to dioxins: 41-139 microg/kg of fat). Of 107 fat samples analysed, polychlorobyphenyls dissimilar to dioxins were detected in two (27 +/- 5 and 30 +/- 5 microg/kg). Out of a total of 94 feed samples analysed, polychlorobyphenyls were detected in all the samples (12) of feed for aquaculture and their raw materials; the concentration of polychlorobyphenyls dissimilar to dioxins varied by an interval of 8-247 microg/kg of fat; polychlorobyphenyls similar to dioxins, between 18 and 107 microg/kg of fat. Contamination by polychlorobyphenyls of the fish from aquaculture could be due to the feed used in these exploitations. The average of trihalomethanes in the waters of the southern zone of Navarra (44 +/- 4 microg/l) was higher than those of the middle zone (16 +/- 1 microg/l) and the mountain zone (12 +/- 1 microg/l). The concentration of 99% of the samples fulfilled the norms on halomethanes. A relation was observed between muddiness and the concentration of trihalomethanes. Herbicide (cianazine) was only detected in one of the 135 samples of water analysed, with a concentration of (0.4 +/- 0.2 microg/l) which exceeded the established limit. The use of confirmation techniques (GC-MS, HPLC-MS/MS) would make it possible to validate these results and to expand the number of compounds analysed.

[Study of the accumulation of lead in the primary teeth]

The purpose of the study was to determine the accumulation of lead in deciduous teeth in children living in the area of Pamplona (Spain). In this manner, we tried to make a relationship between the quantity of lead accumulated in the tooth against certain factors of exposure that were documented on a questionnaire carried out at the time that the tooth was presented. We analysed 457 deciduous teeth using a technique of microwave digestion follow by Atomic Absorption Spectrometry (AAS), to determine the concentration of lead in the sample. The mean lead concentration was 2.60+/-1.36 microg/g (range 0.25-10.71 microg/g). The lead concentration in our study is inferior to those observed in other European studies.

[Weight-loss drugs: composition of diet pills prescribed in Navarra]

BACKGROUND

The prescription, dispensation and sale of "Magisterial formulas" for weight loss is a very extended practice in Spain, in spite of being strongly unadvised by different Administration Department as well as by medical and sanitary groups. The composition of these preparations is not labelled if so only in a generic way.

METHODS

The content of 54 capsules from 6 different origins (3 medical consultations, 1 pharmacist consultation, 1 free sale in pharmacies and 1 free sale in stores) was analysed in 2 laboratories. The presence and quantity of 29 active principles was searched by spectrophotometry, chromatography and radioimmunoassay.

RESULTS

The presence of some of the 12 following substances was confirmed in 42 samples (77.8%): hormones (levothyroxine, cortisol and cortisone), appetite suppression phenetilamines (amphetamine, amphepranone, fenfluramine and fenproporex), benzodiazepines (diazepam, clorazepato and chlordiazepoxide) and diuretics (triamterene and ciclotiazide). The quantities of active principles was very variable in and among the six groups. In 13 of the capsules 1 active principle and in 29 combinations of two or more was found. None component of the labels, when available, corresponded with their analysed components. In 12 samples (22.2%) none of the which may correspond to some substances different from the 29 sought ones.

CONCLUSIONS

The usage of formulas as the studied here on the overweight and obesity treatment should be obviously unadvised.