Arminda Alves

Long lasting perfume--a review of synthetic musks in WWTPs.

Synthetic musks have been used for a long time in personal care and household products. In recent years, this continuous input has increased considerably, to the point that they were recognized as emerging pollutants by the scientific community, due to their persistence in the environment, and hazardous potential to ecosystems even at low concentrations. The number of studies in literature describing their worldwide presence in several environmental matrices is growing, and many of them indicate that the techniques employed for their safe removal tend to be ineffective. This is the case of conventional activated sludge treatment plants (WWTPs), where considerable loads of synthetic musks enter mainly through domestic sewage. This review paper compiles and discusses the occurrence of these compounds in the sewage, effluents and sludge, main concentration levels and phase distributions, as well as the efficiency of the different methodologies of removal applied in these treatment facilities. To the present day, it has been demonstrated that WWTPs lack the ability to remove musks completely. This shows a clear need to develop new effective and cost-efficient remediation approaches and foresees potential for further improvements in this field.

Method Validation for Cafestol and Kahweol Quantification in Coffee Brews by HPLC-DAD

Cafestol and kahweol are two diterpenes exclusively found in coffee. Negative effects on health, like the increase in total lipid blood levels as well as positive effects like carcinogenic protective and antioxidant activity, have been reported for these two compounds. A simple and expeditious method for the quantification of total cafestol and kahweol levels in coffee brews by high-performance liquid chromatography with diode array detection was developed and validated. Esterified diterpenes were hydrolysed and resulting diterpene alcohols extracted with diethyl ether. For cafestol limit of detection was 0.01xa0mgxa0L−1 and limit of quatification was 0.04xa0mgxa0L−1. Coefficient of variation for cafestol ranged between 0.2 and 2.8xa0% for repeatability and between 1.4 and 15.3xa0% for intermediate precision. Average recoveries of cafestol-spiked coffee samples were from 96 to 110xa0%. Kahweol was quantified using cafestol calibration data and corrected by an appropriate conversion factor. Different kinds of coffee brews were analysed. Cafestol levels ranged from 0.04 to 0.80xa0mg/cup and for kahweol levels were between 0.01 and 0.40xa0mg/cup. Highest levels of diterpenes per cup were present in espresso coffee, while the lowest were found in filter coffee and instant coffee.

Environmental distribution of PAHs in pine needles, soils, and sediments

IntroductionThe content of 16 polycyclic aromatic hydrocarbons (PAHs) was determined in 60 samples from three environmental matrices (soils, sediments, and pine needles) in an effort to assess their distribution on a river basin scale.MethodsA sampling campaign was carried out in 2006, selecting urban, industrial, and agricultural sampling sites along the northeast of Spain. Techniques used included pressurized liquid extraction and solid–liquid ultrasonic extraction followed by gas chromatography-electron impact ionization mass spectrometry.ResultsThe mean total PAHs concentrations were 290u2009<u2009613u2009<u20091,628xa0ng/g (dry weight) in pine needles, soil, and sediments, respectively. There is a good correspondence between the total concentration of soils and pine needles, as opposed to the levels between sediments and pine needles. The high concentrations found in some Pinus halepensis samples may reflect a superior uptake potential of this species in comparison to the others studied. The three matrices present a very different PAH distribution pattern, with pine needles showing a predominance of the lighter (2-, 3-, and 4-ring) PAHs, whereas 5- and 6-ring PAHs are the most abundant in soils. Sediments display a more heterogeneous pattern, with contributions of all the PAHs but different distribution depending on the site, suggesting a wider range of input sources. Established PAH molecular ratios and principal component analysis were used to identify the origins and profiles of PAHs. While sediments showed a wide range attributed to historical inputs, soils and pine needles confirmed the compartmentalization of the PAHs, with lighter airborne PAHs accumulated in pine needles and heavier ones in soils.ConclusionsIt can be suggested that the monitoring of several matrices is a strong tool to elucidate the contamination sources and accumulation patterns of PAHs. However, given the influence of the matrix type on this assessment, the information should be considered complementary, yet allowing a more comprehensive depiction of the area in question.

New analytical method for the determination of musks in personal care products by Quick, Easy, Cheap, Effective, Rugged, and Safe extraction followed by GC-MS.

Synthetic musks are organic compounds used as fragrance additives and fixative compounds in a diversity of personal care products. A new method based on quick, easy, cheap, effective, rugged, and safe (QuEChERS) extraction followed by GC-MS for the analysis of 12 musks in personal care products was developed and validated. Some experimental parameters, such as total QuEChERS mass, sample mass/solvent volume ratio, type of extraction solvent, as well as salts and sorbents amount were investigated and optimized. The final method involves the musks extraction using acetonitrile, followed by the addition of anhydrous magnesium sulphate and sodium acetate. The clean-up step was performed using dispersive SPE with primary and secondary amine and octadecyl-silica sorbents. This extraction procedure is fast (about 10 min) when compared to other traditional approaches. The method was robust for the matrices studied and shows a high precision (%RSD < 15%) and accuracy (average recovery of 85%), allowing the detection of musks in minimum concentrations between 0.01 ng/g (galaxolide) and 15.80 ng/g (musk xylene). The developed method was applied to the analysis of 12 samples, which revealed musks concentrations ranging from 2 ng/g (toothpaste) to 882,340 ng/g (perfumed body lotion).

Biomonitoring of pesticides by pine needles — Chemical scoring, risk of exposure, levels and trends

Vegetation is a useful matrix for the quantification of atmospheric pollutants such as semi-volatile organic compounds (SVOCs). In particular, pine needles stand out as effective biomonitors due to the excellent uptake properties of their waxy layer. Having previously validated an original and reliable method to analyse pesticides in pine needles, our work team set the objective of this study to determine the levels of 18 pesticides in Pinus pinea needles collected in 12 different sampling sites in Portugal. These compounds were selected among a total of 70 pesticides by previous chemical scoring, developed to assess their probability to occur in the atmosphere. The risk of exposure was evaluated by the binomial chemical score/frequency of occurrence in the analysed samples. Levels and trends of the chemical families and target of the pesticides were obtained regarding the type of land occupation of the selected sites, including the use of advanced statistics (principal component analysis, PCA). Finally, some correlations with several characteristics of the sampling sites (population, energy consumption, meteorology, etc.) were also investigated.

An analytical multi-residue approach for the determination of semi-volatile organic pollutants in pine needles

Vegetation (and pine needles in particular) has been widely used as an alternative to other conventional sampling devices to assess the atmospheric presence of semi-volatile organic contaminants (SVOCs). While most analytical procedures developed focus only on one or two chemical classes, this this work intends to establish a multi-component protocol to quantify brominated flame-retardants (BFRs), polychlorinated biphenyls (PCBs), organochlorine pesticides (OCPs), polynuclear aromatic hydrocarbons (PAHs) and one class of contaminant of emerging concern, the synthetic musks fragrances (SMCs). Pine needles extracts were obtained by ultrasonic solvents extraction (USE), and different cleanup approaches using solid-phase extraction (SPE) employing combinations of sorbents and solvents as well as gel permeation chromatography (GPC) were tested. SPE with alumina followed by GCP yielded the best results, with average recoveries over 80%. The application of the method under field conditions was proven by the analysis of naturally contaminated samples from 3 sites of different potential exposure (remote, rural and urban). The total detected concentrations ranged from 0.45 to 0.87 ng g(-1) dry weight (dw) for BFRs, 0.35 to 1.01 ng g(-1) (dw) for PCBs, 0.36 to 12.2 ng g(-1) (dw) for HCB, 245.7 to 967.8 ng g(-1) (dw) for PAHs and 20.7 to 277.5 ng g(-1) (dw) for SMCs. This methodology is a viable approach for the simultaneous analysis of five different classes of atmospheric pollutants employing less analytical efforts. Moreover, to the authors best knowledge, this is also the first time vegetation is employed in the detection of SMCs.

Solar photocatalytic oxidation of recalcitrant natural metabolic by-products of amoxicillin biodegradation.

The contamination of the aquatic environment by non-metabolized and metabolized antibiotic residues has brought the necessity of alternative treatment steps to current water decontamination technologies. This work assessed the feasibility of using a multistage treatment system for amoxicillin (AMX) spiked solutions combining: i) a biological treatment process using an enriched culture to metabolize AMX, with ii) a solar photocatalytic system to achieve the removal of the metabolized transformation products (TPs) identified via LC-MS, recalcitrant to further biological degradation. Firstly, a mixed culture (MC) was obtained through the enrichment of an activated sludge sample collected in an urban wastewater treatment plant (WWTP). Secondly, different aqueous matrices spiked with AMX were treated with the MC and the metabolic transformation products were identified. Thirdly, the efficiency of two solar assisted photocatalytic processes (TiO2/UV or Fe(3+)/Oxalate/H2O2/UV-Vis) was assessed in the degradation of the obtained TPs using a lab-scale prototype photoreactor equipped with a compound parabolic collector (CPC). Highest AMX specific biodegradation rates were obtained in buffer and urban wastewater (WW) media (0.10 ± 0.01 and 0.13 ± 0.07 g(AMX) g(biomass)(-1) h(-1), respectively). The resulting TPs, which no longer presented antibacterial activity, were identified as amoxicilloic acid (m/z = 384). The performance of the Fe(3+)/Oxalate/H2O2/UV-Vis system in the removal of the TPs from WW medium was superior to the TiO2/UV process (TPs no longer detected after 40 min (QUV = 2.6 kJ L(-1)), against incomplete TPs removal after 240 min (QUV = 14.9 kJ L(-1)), respectively).

Microwave-assisted headspace solid-phase microextraction to quantify polycyclic aromatic hydrocarbons in pine trees

A methodology for the extraction and quantification of 16 polycyclic aromatic hydrocarbons (PAHs) based on microwave-assisted extraction coupled with headspace solid-phase microextraction followed by gas chromatography/mass spectroscopy was validated for needles and bark of two pine species (Pinus pinaster Ait. and Pinus pinea L.). The limits of detection were below 0.92xa0ngxa0g−1 (dry weight) for needles and below 0.43xa0ngxa0g−1 (dw) for bark. Recovery assays were performed with two sample masses spiked at three levels and the overall mean values were between 70 and 110xa0% for P. pinaster and 75 and 129xa0% for P. pinea. In the first species, the increase in sample mass lowered the recoveries slightly for most PAHs, whereas for the second, the recoveries were higher for the needles. Naturally contaminated samples from 4 sites were analysed, with higher levels for urban sites (1,320 and 942xa0ngxa0g−1 (dw) vs. 272 and 111xa0ngxa0g−1 (dw) for needles and 696 and 488xa0ngxa0g−1 (dw) vs. 270 and 103xa0ngxa0g−1 (dw) for bark) than for rural ones and also for P. pinaster samples over P. pinea. It is also shown that gas-phase PAHs are predominant in the needles (over 65xa0% of the total PAHs) and that the incidence for particulate material in bark, reaching 40xa0% as opposed to a maximum below 20xa0% for the needles. The method has proved to be fit and improved some of the existing approaches, on the assessment of particulate PAHs and bark levels.

Diterpenes in espresso coffee: impact of preparation parameters

The aim of the present study was to evaluate the effect of preparation conditions of espresso coffee (EC) on the diterpenes profile. ECs were prepared from roasted and ground (R&G) Arabica coffee and analyzed for the content of cafestol and kahweol by liquid–liquid extraction followed by HPLC-DAD, as well as their lipid content. The main variables in the present study were as follows: the water quantity, the amount of coffee, the particle size, the percolation time, the water temperature and pressure. Average cafestol, kahweol and lipid content of R&G Arabica coffee were 467xa0±xa020xa0mg/100xa0g, 638xa0±xa033xa0mg/100xa0g and 15.1xa0±xa00.1xa0g/100xa0g, respectively. Although all parameters influenced the diterpenes content of ECs (21 samples), the particle size and water quantity were the most significant ones. It was possible to reduce the total diterpenes from 58.8xa0±xa00.7xa0mg/L (2.3xa0mg/40xa0mL) to 30.7xa0±xa00.8xa0mg/L (1.2xa0mg/40xa0mL) by varying the brewing conditions. The averagexa0extraction yield of diterpenes and lipids was in the range of 1.5–2.5 and 7.0–9.0xa0%, respectively. Regarding total cafestol and kahweol, very fine particles seem to be more desirable for the production of highly concentrated brew (2.3xa0mg/40xa0mL) with cafestol and kahweol extraction yields of 2.8 and 2.9xa0%, respectively, than other studied ECs. On the other hand, samples brewed at 70xa0°C exhibited lower diterpenes content (1.2xa0mg/40xa0mL) and diterpenes extraction efficiency (1.4xa0%) with respect to all other considered parameters. This study clearly shows that parameters for coffee brew preparation may be changed to modify the diterpenes content of ECs according to the desired purpose.

Quantification of Diterpenes and Their Palmitate Esters in Coffee Brews by HPLC-DAD

The present article aimed the optimization of the saponification and extraction of diterpenes from coffee brews using a simple methodology based on high performance liquid chromatography with diode array detector (HPLC-DAD), as well as to quantify the diterpenes and their palmitate esters content in several coffee brews. Regarding cafestol and kahweol, the best conditions to maximize total extraction yield were achieved through the direct saponification of 2.5 mL of coffee brew along with 3.00 g of potassium hydroxide in a water bath (80°C). The proposed method consists in two sequential extractions using diethyl ether followed by a clean-up with 5 mL of 2 M NaCl solution prior to analysis in order to eliminate soap and co-eluting interferences. Cafestol and kahweol palmitates also were quantified using the same procedure, but without the saponification step. The proposed methods exhibited high accuracy (average recovery of 85%) and linearity (R2 > 0.999) and good precision (%CV < 5%) with low limit of detection (less than 0.25 mg/L) and limit of quantification (less than 0.70 mg/L). Comparison of different brewing techniques revealed that capsule coffee with individual cup size of 50 mL contained the highest cafestol (1.85 mg/cup) and kahweol (2.75 mg/cup) content. In contrast, the lowest values of diterpenes were found in filter coffee (0.1 mg cafestol and 0.03 mg kahweol/200 mL). The higher and lower values of palmitate esters were also obtained from capsule and filter coffee, respectively. The proposed methods were simple, time saving and require low solvent consumption for quantification of diterpenes and their palmitate esters in various types of coffee brews.