Rainfall-induced removal of copper-based spray residues from vines.

The continuous use of copper against fungal diseases and off-target effects causes major environmental and agronomic problems. However, the rain-induced removal of Cu-based residues is known only for a limited number of crops. We present the results of rain-induced removal of fungicides from two monitored vineyard plots which were sprayed with two widely used Cu-based formulations: copper-oxychloride (CO) and Bordeaux mixture (BM), respectively. Cu removal per growing season was 0.60±0.12kgha(-1) (30% of the applied fungicide) for CO and 0.80±0.10kgha(-1) for BM (70% of the applied fungicide). Fractioning the Cu in soluble (CuS) and particulate fractions (CuP) showed that most of the Cu was removed as CuP, but CuS concentrations found in throughfall collectors exceeded the regulatory threshold for toxicity in surface waters. The first few millimeters of rain caused most of the Cu removal. Our findings agreed with the data reported in the scientific literature, in which a significant fraction of the Cu-based formulation is loosely attached to the plant surfaces. In addition, we found that rainfall energy had a minor influence on the removal.

Coumarins as turn on/off fluorescent probes for detection of residual acetone in cosmetics following headspace single-drop microextraction.

In this work, a new method based on headspace-single drop microextraction for the determination of residual acetone in cosmetics by microfluorospectrometry is proposed. Acetone causes fluorescence changes in a 2.5 µL-ethanolic drop (40% v/v) containing 3.10(-4) mol L(-1) 7-hydroxy-4-methylcoumarin ('turn off') or 6.10(-6) mol L(-1) 7-diethylamino-4-methylcoumarin ('turn on'). Polarity and ability to form hydrogen bonds of short chain alcohols (polar protic solvents) were crucial in order to observe these changes in the presence of acetone (polar aprotic solvent). Parameters related with the HS-SDME procedure were studied, namely headspace volume, composition, volume and temperature of drop, microextraction time, stirring rate, mass and temperature of sample, as well as the effect of potential interferents (alcohols and fragrances). The high volatility of acetone allows its extraction from an untreated cosmetic sample within 3 min. A detection limit of 0.26 µg g(-1) and repeatability, expressed as relative standard deviation, around 5% were reached. Accuracy of the proposed methodology was evaluated by means of recovery studies. The method was successfully used to analyze different cosmetics. Simplicity and high sample throughput can be highlighted.

Ultrasound-assisted single extraction tests for rapid assessment of metal extractability from soils by total reflection X-ray fluorescence.

In this work, ultrasound-assisted extraction (UAE) was employed for acceleration of metal extraction from soil samples. After extraction, multielemental analysis (Cr, Mn, Fe, Ni, Cu, Zn and Pb) of EDTA and acetic acid extracts was performed by total reflection X-ray fluorescence spectrometry (TXRF). High-intensity ultrasonic processors, i.e. the ultrasonic probe (50W) and the cup-horn sonoreactor (200W) were applied. Both ultrasonic procedures were compared with a miniaturized version of the single extraction scheme proposed by the Standards, Measurements and Testing program (SM&T). The extraction time with EDTA was reduced from 1h (conventional procedure) to 2 min (ultrasonic probe) or to 10 min (cup-horn sonoreactor). The time required for acetic acid extraction was also reduced from 16 h (conventional procedure) to 6 min (ultrasonic probe) or to 30 min (cup-horn sonoreactor). In addition, the amount of sample and extractants was drastically reduced as a result of the miniaturization implemented in the developed approaches. The combination of UAE and TXRF allows assessing the potential metal mobility and bioavailability in a simple way.

Ion pair-based dispersive liquid-liquid microextraction for gold determination at ppb level in solid samples after ultrasound-assisted extraction and in waters by electrothermal-atomic absorption spectrometry.

A new methodology was developed for the determination of ultratrace levels of gold in water samples, soils and river sediments. Dispersive liquid-liquid microextraction was used to preconcentrate the ion pair formed between AuCl(4)(-) and [CH(3)(CH(2))(3)](4)N(+) in a microliter-range volume of chlorobenzene using acetone as disperser solvent. When solid samples were analyzed, the method consisted of a combination of ultrasound-assisted extraction and dispersive liquid-liquid microextraction with final detection by electrothermal-atomic absorption spectrometry. Since an HCl medium was required for the formation of the AuCl(4)(-) complex, HCl together with HNO(3) was used as extractants for ultrasound-assisted extraction. After optimization, the enrichment factor obtained was 220 for water samples. Moreover, the extraction efficiency was around 96%. The repeatability, expressed as relative standard deviation ranged from 3.6% to 9.7%. The instrumental detection limit was 8.4 ng L(-1), whereas the procedural detection limits were 42 ng L(-1) for water samples and 1.5 ng g(-1) for environmental solid samples.

Simultaneous ultrasound-assisted emulsification-derivatization as a simple and miniaturized sample preparation method for determination of nitrite in cosmetic samples by microvolume UV-vis spectrophotomety.

A simple and miniaturized approach based on ultrasound-assisted emulsification-derivatization is proposed for the determination of nitrite in cosmetic samples by UV-vis micro-spectrophotometry. Oil/water emulsions were formed using 15 mg of cosmetic sample and 1 mL of an aqueous medium containing 0.5% w/v SDS and 1% v/v acetic acid. When powerful sonication systems were used to make emulsions, i.e. probe or cup-horn sonoreactor, stable and transparent emulsions were obtained in one or half minute per sample, respectively. The Griess reaction in these special conditions (i.e. sonication and the presence of an organized medium) was investigated. The absence of matrix effects allows external calibration with aqueous standards for nitrite quantification. Analytical features were compared to those of the European official method 82/434/EEC. Detection limit, sample throughput and reagent consumption were significantly improved.

Evaluation of ultrasound-assisted extraction as sample pre-treatment for quantitative determination of rare earth elements in marine biological tissues by inductively coupled plasma-mass spectrometry.

In this work, the determination of rare earth elements (REEs), i.e. Y, La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb and Lu in marine biological tissues by inductively coupled-mass spectrometry (ICP-MS) after a sample preparation method based on ultrasound-assisted extraction (UAE) is described. The suitability of the extracts for ICP-MS measurements was evaluated. For that, studies were focused on the following issues: (i) use of clean up of extracts with a C18 cartridge for non-polar solid phase extraction; (ii) use of different internal standards; (iii) signal drift caused by changes in the nebulization efficiency and salt deposition on the cones during the analysis. The signal drift produced by direct introduction of biological extracts in the instrument was evaluated using a calibration verification standard for bracketing (standard-sample bracketing, SSB) and cumulative sum (CUSUM) control charts. Parameters influencing extraction such as extractant composition, mass-to-volume ratio, particle size, sonication time and sonication amplitude were optimized. Diluted single acids (HNO(3) and HCl) and mixtures (HNO(3)+HCl) were evaluated for improving the extraction efficiency. Quantitative recoveries for REEs were achieved using 5 mL of 3% (v/v) HNO(3)+2% (v/v) HCl, particle size <200 µm, 3 min of sonication time and 50% of sonication amplitude. Precision, expressed as relative standard deviation from three independent extractions, ranged from 0.1 to 8%. In general, LODs were improved by a factor of 5 in comparison with those obtained after microwave-assisted digestion (MAD). The accuracy of the method was evaluated using the CRM BCR-668 (mussel tissue). Different seafood samples of common consumption were analyzed by ICP-MS after UAE and MAD.

Novel (60%) and recurrent (40%) androgen receptor gene mutations in a series of 59 patients with a 46,XY disorder of sex development.

BACKGROUND: Androgen receptor (AR) gene mutations are the most frequent cause of 46,XY disorders of sex development (DSD) and are associated with a variety of phenotypes, ranging from phenotypic women [complete androgen insensitivity syndrome (CAIS)] to milder degrees of undervirilization (partial form or PAIS) or men with only infertility (mild form or MAIS). OBJECTIVE: The aim of the study was to characterize the contribution of the AR gene to the molecular cause of 46,XY DSD in a series of Spanish patients. SETTING: We studied a series of 133 index patients with 46,XY DSD in whom gonads were differentiated as testes, with phenotypes including varying degrees of undervirilization, and in whom the AR gene was the first candidate for a molecular analysis. METHODS: The AR gene was sequenced (exons 1 to 8 with intronic flanking regions) in all patients and in family members of 61% of AR-mutated gene patients. RESULTS: AR gene mutations were found in 59 individuals (44.4% of index patients), of whom 46 (78%) were CAIS and 13 (22%) PAIS. Fifty-seven different mutations were found: 21.0% located in exon 1, 15.8% in exons 2 and 3, 57.9% in exons 4-8, and 5.3% intronic. Twenty-three mutations (40.4%) had been previously described and 34 (59.6%) were novel. CONCLUSIONS: AR gene mutation is the most frequent cause of 46,XY DSD, with a clearly higher frequency in the complete phenotype. Mutations spread along the whole coding sequence, including exon 1. This series shows that 60% of mutations detected during the period 2002-2009 were novel.

Ultrasound-assisted emulsification of cosmetic samples prior to elemental analysis by different atomic spectrometric techniques.

In this work, ultrasound-assisted emulsification with a probe system is proposed as a rapid and simple sample treatment for atomic spectrometric determinations (Electrothermal Atomic Absorption Spectrometry, Inductively Coupled Plasma Optical Emission Spectrometry, Flame Atomic Absorption Spectrometry and Cold Vapour Atomic Absorption Spectrometry) of trace elements (As, Cd, Cr, Cu, Hg, Mg, Mn, Ni, Sr and Zn) in cosmetic samples such as shampoos, gel (hair gel), crèmes (body milk, hair conditioner) and oil (body oil). The type of dispersion medium, the sample mass-to-dispersion medium volume ratio, as well as the parameters related to the ultrasound-assisted emulsification (sonication amplitude and treatment time) were exhaustively studied. Only 1 min of ultrasonic shaking and a dispersion medium containing 0.5% (w/v) of SDS+3% (v/v) of HNO(3) or HCl allows obtaining a stable emulsion at least for 3 months. Thermal programs, nebulization of emulsions, speed of pumps and concentration of reagents used in cold vapour generation were optimized. Calibration using aqueous standards was feasible in all cases. Calibration by the standard addition method and recovery studies was also applied for validation. Microwave-assisted digestion and Inductively Coupled Plasma Mass Spectrometry were used for comparison purposes. Relative standard deviations from analysis of five independent emulsions were less than 9% in all cases.

[Prevalence of hepatitis B markers in the personnel of psychiatric hospitals]. / Prevalencia de marcadores de la hepatitis B entre el personal laboral de un hospital psiquiátrico.

The current rules and regulations in Spain state that those working in closed institutions, helping mentally disturbed patients, are considered personnel at risk for acquiring hepatitis B virus infection, without drawing distintions between professions and fields of work. The immunological state against HBV has been studied in a representative population group of workers of the Cadiz Provincial Psychiatric Hospital (82.90%). Our results show that the percentage of chronic carriers (3.15%) and those with other positive biological markers (30.07%) is greater than that found in the General hospitals of our country. Thus, the inclusion of this population group in preventive programs as well as vaccination programs against hepatitis B virus infection is totally justified.