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Given the possibility of exposure to various metals by inappropriate use of some commercially available hygiene products, it becomes necessary to develop simpler and more cost-affordable procedures to quantify those analytes in different matrices, allowing a local quality control even for smaller producers and industries. In this context, electroanalytical techniques, especially using stripping voltammetry, have been an alternative due to the relatively low cost of implementation and operation, high sensitivity, accuracy and applicability in environments with high ionic strength. Transitory modifications based on bismuth films stands for a viable alternative in gaining sensitivity and resolution, replacing mercury films, with simpler preparation and operation. Electrode modification can also be accomplished with organic films, which can be made, for example, by reduction of diazonium salts. In this paper, we present the development and application of two different modified systems, using a manufactured composite electrode composed of graphite (65%, m/m) dispersed in epoxy resin, for determination of Pb2+, Cd2+ and Zn2+ in color wash lotion and anti-dandruff shampoo. Two modifications were implemented: in situ bismuth film and ex situ organic film by diazonium salt reduction. Determinations were carried out in acetate buffer pH 6.0 with deposition potential of −1.4 V (applied during 120 s, with stirring), followed by voltammetric square wave measurements and subsequent cleaning with application of 0.3 V potential. Detection limits of 0.07, 0.05 and 0.06 µmol L−1 were achieved for lead, cadmium and zinc, respectively. The method was applied to hair cosmetic products such as color wash lotion (with lead acetate as its active), and anti-dandruff shampoo (with zinc in the forms of pyrithione and carbonate as actives). All studied samples have shown results in accordance with local regulations and product labels. The results were compared to those found by applying flame atomic absorption spectrometry, being considered statistically equivalent.

The present work reports the variation of 31 carbonyl compounds (CC) in an apartment located at Niterói City, Rio de Janeiro State, Brazil. Eight sampling campaigns were conducted through a 1-year period, and three areas (living room, kitchen, and bedroom) were evaluated before, during, and after the renovation activities and reoccupation of the apartment. Samples were collected using SEP-PAK cartridges impregnated with 2,4-dinitrophenylhydrazine, and the hydrazones were analyzed using rapid resolution liquid chromatography with UV detection. The lowest total concentration of CC (19.0 ± 1.5 μg m(-3)) was found before the renovation when the apartment was empty, but door varnishing resulted in highest contamination of the apartment (1386 ± 384 μg m(-3)); however, an important dispersion of CC was observed in the subsequent sampling (148 ± 1.8 μg m(-3)). After apartment reoccupation, the indoor contamination seemed to depend on the routine activities taken there, such as household product use and cooking activities, but apparently, local temperature increase favored the vaporization of the volatile CC from the building materials in the apartment. As far as we are concerned, this is the first study comparing the concentrations of 31 CC in residential areas before, during, and after renovation activities taken in Brazil.

Caffeine is widely present in food and drinks, such as teas and coffees, being also part of some currently commercialized medicines, but despite its enhancement on several functions of human body, its exceeding use can promote many health problems. In order to develop new fast approaches for the caffeine sensing, graphite-epoxy composite electrodes (GECE) were used as substrate, being modified by different diazonium salts, synthetized as their tetraflouroborate salts. An analytical method for caffeine quantification was developed, using sware wave voltammetry (SWV) in Britton–Robinson buffer pH 2.0. Detection limits for bare electrode and 4-benzenesulfonic modified electrode were observed circa 145 µmol·L−1 and 1.3 µmol·L−1, respectively. The results have shown that the modification shifts the oxidation peaks to lower potential. Kinetics of the reaction limited by diffusion was more expressive when caffeine was added to the solution, resulting in decreases of impedance, characterized by lower Rct. All results for caffeine determination were compared to a reference chromatographic procedure (HPLC), showing no statistical difference. Analytical parameters for validation were suitably determined according to local legislation, leading to a linear behaviour from 5 to 150 µmol·L−1; precision of 4.09% was evaluated based on the RDC 166/17, and accuracy was evaluated in comparison with the reference method, with recovery of 98.37 ± 2.58%.

Macrocyclic lactones (ML) are commonly used in drug formulations for the treatment of parasites in cattle. In Brazil, except for drugs (or formulations) with long-term (half-life) effects, ML are registered for use in bovines. Indiscriminate use of ML may result in the presence of residues in milk and dairy products due to their lipophilic properties and thermal stability. This study applied a method of liquid chromatography with fluorimetric detection, recently developed and validated for the determination of residues of abamectin, doramectin, ivermectin, and moxidectin in butter. The method was applied to 38 samples of commercial butter purchased in the metropolitan area of Rio de Janeiro, Brazil, between June and September 2013, analyzed in triplicate. Ivermectin was detected in 89.5% of the samples, with concentrations between 0.3 and 119.4 µg/kg; 76.3% of the samples contained doramectin (0.6 to 64.7 µg/kg) and 55.2% contained abamectin (0.7 to 4.5 µg/kg). Most butter samples (76.3%) contained residues of more than 1 ML; however, no residues of moxidectin were detected. The results showed a high incidence of the presence of avermectins in butter samples. Butter is not included in the Brazilian National Plan for Control of Residues and Contaminants in Animal Products. As ML residues concentrate in lipophilic compounds, butter and other fatty dairy products should be screened for the presence of ML residues.

Atmospheric particulate matter (total suspended particulate – TSP – and inhalable particles – PM10) and gas-phase samples were collected in three periods of seven to nine consecutive days in June and December 2011, and May 2012, in the central area of Niteroi City, Rio de Janeiro State, Brazil. TSP (48.8–214 μg m−3) showed higher concentrations than PM10 (nd – 82.6 μg m−3). Sixteen polycyclic aromatic hydrocarbons (PAH) and thirty-one carbonyl compounds (CC) were evaluated. Concentrations of individual PAH ranged from

Fifteen polycyclic aromatic hydrocarbons (PAHs) were analyzed in two fractions (

This study describes the determination of 30 carbonyl compounds (CCs) in three areas (bus boarding platform, passenger circulation area, and a pastry shop) of the Presidente Joao Goulart Bus Terminal, located at Niteroi City, RJ, Brazil, and in an open area 700 m distant from the terminal. Samples were collected using SEP-PAK cartridges impregnated with 2,4-dinitrophenylhydrazine, during May to July 2012. The hydrazones formed were analyzed using rapid resolution liquid chromatography with UV detection. The studied locations showed distinct profiles of distribution of CC. The circulation area, which is influenced by different pollution sources, presented an intermediate profile between that of the pastry shop and boarding platform. Formaldehyde and acetaldehyde were the most abundant CC, but acetaldehyde predominated in the pastry shop once it is a by-product of baking yeast fermentation. Samples taken in the pastry shop and circulation area showed significant concentrations of hexanaldehyde and nonanaldehyde emitted during cooking. The pastry shop showed the largest level of total CC among the studied areas followed by the circulation area, the boarding platform, and the open area.