Search

The global water bottling market grows annually. Today, to ensure consumer safety, it is important to verify the possible migration of compounds from bottles into the water contained in them. Potential health risks due to the prevalence of bisphenol A (BPA) and phthalates (PAEs) exposure through water bottle consumption have become an important issue. BPA, benzyl butyl phthalate (BBP), di-n-butyl phthalate (DBP) and di (2-ethylhexyl) phthalate (DEHP) can cause adverse effects on human health. Papers of literature published in English, with BPA, BBP, DBP and DEHP detections during 2017, by 2019 by liquid chromatography and gas chromatography analysis methods were searched. The highest concentrations of BPA, BBP, DBP and DEHP in all the bottled waters studied were found to be 5.7, 12.11, 82.8 and 64.0 μg/L, respectively. DBP was the most compound detected and the main contributor by bottled water consumption with 23.7% of the Tolerable Daily Intake (TDI). Based on the risk assessment, BPA, BBP, DBP and DEHP in commercial water bottles do not pose a serious concern for humans. The average estrogen equivalent level revealed that BPA, BBP, DBP and DEHP in bottled waters may induce adverse estrogenic effects on human health. HIGHLIGHTS DBP was the most compound detected.; An estimated intake of BPA, BBP, DBP and DEHP was far below their TDIs.; The risk assessment of BPA, BBP, DBP and DEHP does not raise serious concern for humans.; The average estrogen equivalent level for BPA, BBP, DBP and DEHP may induce adverse estrogenic effects on human health.; BPA, BBP, DBP and DEHP in bottled water need more accurate data to avoid their effects on human health.

The multi-indicators (chemical, biological, and physical), as well as their associated risks to human health, were assessed at the same time as an assessment of the use of sites for physical activity. The sampling was conducted in both the dry and wet seasons in 2014, between 4:30 and 7:30 pm, a period considered the “peak hours” of traffic and also the time that most people practice physical activity. Regarding the chemical indicators, the distribution of carbonyl compound levels should be influenced by the flow of vehicles, while the respirable particles are governed by the number of diesel vehicles. The cancer risk corresponding to the value recommended by National Institute for Occupational Safety and Health (NIOSH) for formaldehyde was exceeded only in the dry season in one location studied. The risk of non-carcinogenic substances showed that acrolein levels at all locations and in the two periods studied might cause adverse effects to the health of the recreation site users. Exposure to respirable particles at levels corresponding to the value recommended by the United States Environmental Protection Agency (US-EPA) was exceeded in all locations during the two study periods. For biological indicators, only the bacteria levels show pollution ranging from medium to high for the two sites in both periods studied. Regarding the physical indicators, the noise levels in the studied sites exceeded the standards recommended by the World Health Organization (WHO) and US-EPA. In most places, the thermal comfort was close to 40, which is classified as “supportable discomfort.”

The main carbonyl compounds (CCs) were determined at gas stations for the first time in Fortaleza city, CE, Brazil, and the results were compared with other urban centers. The influence of seasonality on the production, distribution and balance of CCs, as well as the associated cancer risks, was also estimated. Formaldehyde was the most abundant carbonyl, followed by acetaldehyde, nonaldehyde, acrolein, butyraldehyde and benzaldehyde. The total CC concentration (ΣCC) averages are less than most other studies in outdoor environments and gas stations. The ΣCCs were higher in the dry period than in the wet period. It was observed that the insolation, cloud cover and precipitation should be influencing CCs distribution, while the ambient temperature should not. The study showed that the cancer risks associated with formaldehyde and acetaldehyde are 3.9 and 1.5 times higher, respectively, during the dry period than during the wet period. The cancer risk in the months of dry period of the year were observed to exceed the recommended exposure limit established by National Institute for Occupational Safety and Health (NIOSH).

In this study, the adsorption efficiency of cashew peduncle bagasse (CPB) is reported for the removal of single-(mono-) and multi-metal ions (Cd2+; Cu2+; Ni2+; Pb2+; and Zn2+) from synthetic and natural effluents using fixed-bed columns. The percentage of saturation realised in this study using a mono-elemental system was as follows: Pb2+ > Cd2+ > Zn2+ > Ni2+ > Cu2+. The metal ion recovery rate was determined by column elution; we demonstrated 100% metal ion recovery using 40 mL of HCl or HNO3 (0.1 mol L−1) as the eluent, with the exception of Pb2+. The adsorbent regeneration process decreased the removal efficiencies to 90% (Pb2+), 44% (Cu2+), 99% (Ni2+), 81% (Cd2+) and 74% (Zn2+) after the first cycle. The breakthrough curves and kinetic adsorption factors controlling the adsorption process were also studied. The Thomas model has produced the best fit with the experimental data.

We measured polycyclic aromatic hydrocarbons (PAHs) in bulk precipitation in the Fortaleza metropolitan area, Ceará, Brazil, for the first time. Because little information is available concerning PAHs in tropical climatic regions, we assessed their spatial distribution and possible sources and the influence of urban activities on the depositional fluxes of PAHs in bulk precipitation. The concentrations of individual and total PAHs (Σ(PAHs)) in bulk precipitation ranged from undetectable to 133.9 ng.L(-1) and from 202.6 to 674.8 ng.L(-1), respectively. The plume of highest concentrations was most intense in a zone with heavy automobile traffic and favorable topography for the concentration of emitted pollutants. The depositional fluxes of PAHs in bulk precipitation calculated in this study (undetectable to 0.87 μg.m(-2).month(-1)) are 4 to 27 times smaller than those reported from tourist sites and industrial and urban areas in the Northern Hemisphere. Diagnostic ratio analyses of PAH samples showed that the major source of emissions is gasoline exhaust, with a small percentage originating from diesel fuel. Contributions from coal and wood combustion were also found. Major economic activities appear to contribute to pollutant emissions.

Solid residues of the agroindustries are abundantly available at low cost and, because of their adsorption properties, they could be advantageously used for the treatment of industrial effluents. In this work, base-treated green coconut shell powder was applied to remove toxic metals from synthetic aqueous effluents. It was shown that Langmuir and Freundlich isotherms describe the adsorption features in single and multicomponent systems.

The levels of internal and external concentrations of formaldehyde and acetaldehyde, as well as occupational risk based on individual exposure to and potential carcinogenic effects of these, were evaluated in eight environments of two hospitals in the city of Fortaleza-CE during September and October of 2009. The results depicted a variation of 1.98–24.87 μg m −3 formaldehyde and of 9.38–55.10 μg m −3 acetaldehyde; the main sources of emissions were internal. The exposure levels showed values above the allowable limits for some of the environments studied (permissible exposure limits estimated as an 8-h time-weighted average (PEL-TWA)). The estimation of total cancer risk is of a similar magnitude to other studies, and the risk is 12–18% greater for women than men.

Isomorphously substituted (MeDM) and impregnated metal-containing MCM-41 (MeOx/IM) catalysts, in which Me = Co, Cu, Cr, Fe or Ni, have been prepared. Structural and textural characterizations of the catalysts were performed by means of X-ray diffraction (XRD), chemical analysis, Raman spectroscopy, electron paramagnetic resonance (EPR), N2 adsorption isotherms and temperature programmed reduction (TPR). Cu2+, Co2+, and Cr4+/Cr3+ species were found over the catalysts as cations incorporated in the MCM-41 structure (MeDM) or highly dispersed oxides on the surface (MeOx/IM). The MeDM catalysts exhibited a good performance in the dehydrogenation of ethylbenzene with CO2. However, MeOx/IM catalysts had a low performance in styrene production (activity less than 15 × 10−3 mmol h−1 and selectivity for styrene less than 80%) due to the high reducibility of the metals species. However, Ni2+ or Fe3+ coordinated with the MCM-41 framework, as well as NiOx and Fe2O3 extra-framework species, is continuously oxidized by the CO2 to maintain the active sites for dehydrogenating ethylbenzene. Deactivation studies on the FeDM sample showed that Fe3+ species produced active sp2 carbon compounds, which are removed by CO2; the referred sample is catalytically selective for styrene and stable over 24 h of reaction. In contrast, highly active Ni2+ and Ni0 species produced a large amount of polyaromatic carbonaceous deposits from styrene, as identified by TPO, TG and Raman spectroscopy. An acid–base mechanism is proposed to operate to adsorb ethylbenzene and abstract the β-hydrogen. CO2 plays a role in furnishing the lattice oxygen to maintain the Fe3+ active sites in the dehydrogenation of ethylbenzene to form styrene.

Neste trabalho são apresentados os resultados obtidos com processo oxidativo avançado (POA) convencional (UV/H2O2) e combinado com o processo de adsorção (POA-Adsorção) no tratamento de um efluente têxtil. A eficiência do tratamento do efluente foi avaliada pelos parâmetros cor, demanda química de oxigênio (DQO), pH, Sólidos totais, condutividade e turbidez, de efluente de uma indústria têxtil. O eficaz tratamento do efluente foi obtido com H2O2 1% (m/v) sob radiação ultravioleta por tempo de recirculação de 1, 2, 3, e 4h, em pH alcalino. A remoção de cor variou de 73,17% a 96,44%, enquanto que a redução de DQO variou de 50,33% a 73,27% para um tempo de contato de 4 horas. Resultados obtidos utilizando o tratamento combinado POA/Adsorção mostraram uma leve melhora frente aos demais.

This investigation represents the first environmental diagnosis of the distribution and sources of polycyclic aromatic hydrocarbons (PAHs) in sediments from a tropical mangrove in Fortaleza, northeastern Brazil. Sediment cores from six sampling stations in the Cocó and Ceará Rivers were retrieved in June-July 2006 to determine 17 priority PAHs. The total PAH concentrations (Sigma(PAHs)) ranged from 3.04 to 2234.76 microg kg(-1)(Cocó River) and from 3.34 to 1859.21 microg kg(-1) (Ceará River). These levels are higher than those of other cities with more industrial development. PAH concentrations did not reach probable effect levels (PELs). However, from 4.5 to 87.5% of individual PAH concentrations can occasionally cause adverse biological effects for aquatic organisms. The PAH molecular ratios indicate that the PAHs in the sediment core were derived mainly from petroleum, wood, and charcoal combustion (pyrogenic source), and that atmospheric deposition and urban runoff may serve as important pathways for PAH input to the sediment. Clearly, the Sigma(PAHs) in sediments collected in the Cocó and Ceará Rivers indicate that ongoing pollution is more severe than past pollution.

In this work, 8-hydroxyquinoline is used as the active sites in cross-linked chitosan beads with epichlorohydrin (CT-8HQ). The CT-8HQ material was shaped in bead form and used for heavy metal removal from aqueous solution. The study was carried out at pH 5.0 with both batch and column methods and the maximum adsorption capacity of metal ions by the CT-8HQ was attained in 4 h in the batch experiment. The adsorption capacity order was: Cu 2+ > Ni 2+ > Zn 2+ for both mono- and multi-component systems with batch conditions. From breakthrough curves with column conditions, the adsorption capacity followed the order Cu 2+ > Zn 2+ > Ni 2+ for both mono-and multi-component systems. The CT-8HQ beads maintained good metal adsorption capacity for all five cycles with absorbent restoration achieved with the use of 1.0 mol L -1 HCl solution, with 90% regeneration.

UV/H2O2system was tested on the color removal of sulfonated azo dye Reactive Red 198 (RR), which is widely used in textile process. The effects of hydrogen peroxide concentration, temperature, pH, and the in-line addition of hydrogen peroxide on high color and chemical oxygen demand (COD) removals were investigated. The kinetic of dye decolorization was also determined. The results showed that 2% H2O2decreased the process efficiency, while 1% H2O2solution led to a better performance of the system. Despite the fact that the pH increase had small effect on color removal, it affects positively COD removals. The same behavior was found for temperature increase. A high temperature resulted in a slight decrease in color removal and a sharp decrease for COD removal. In addition the H2O2in-line provided a small improvement in both color and COD removals. UV/1% H2O2treatment was the most efficient, the good performance was linked to higher amount of hydroxyl radicals formed.

Ronaldo Ferreira do. Nascimento1, Francisco Wagner de Sousa1, Vicente Oliveira Sousa Neto2, Pierre Basilio Almeida Fechine1, Raimundo Nonato Pereira Teixeira3, Paulo de Tarso C. Freire1 and Marcos Antonio Araujo-Silva1 1Universidade Federal do Ceara (UFC), 2Universidade Estadual do Ceara (UECE-CECITEC), 3Universidade Regional do Cariri (URCA), 4Instituto Federal de Educacao, Ciencia e Tecnologia (IFCE-Crateus) Brazil

This study applies green coconut shells as adsorbent for the removal of toxic metal ions from aqueous effluents using column adsorption. The results show that a flow rate of 2 mL/min and a bed height of 10 cm are most feasible. Furthermore, larger amounts of effluent can be treated for removal of single ions. The breakthrough curves for multiple elements gave the order of adsorption capacity: Cu+2 > Pb+2 > Cd+2 > Zn+2 > Ni+2. Real samples arising from the electroplating industry can be efficiently handled.

The metal ions removal on cashew bagasse, a low-cost material, has been studied by batch adsorption. The parameters chemical treatment, particle size, biosorbent concentration, and initial pH were studied. In this study the maximum ions removal was obtained on the cashew bagasse treated with 0.1 mol/L NaOH/3 h, at optimum particle size (20-59 mesh), biosorbent concentration (50 g/L) and initial solution pH 5. The kinetic study indicated that the adsorption metal follows pseudo-second order model for a multielementary system and equilibrium time was achieved in 60 min for all metal ions.

In this study, sugar cane residue or bagasse was used for removal of toxic metal ions from wastewater of an electroplating factory located in northeast Brazil. Prior acid treatment increased the adsorption efficacies in batch wise experiments. The microstructure of the material before and after the treatment was investigated by X-ray diffraction, infrared spectroscopy and scanning electron microscopy. Column operations showed that removals of Cu 2+ , Ni 2+ and Zn 2+ from wastewater (in the absence of cyanide) were 95.5%, 96.3.0%, and 97.1%, respectively. Regeneration of the adsorbent obtained in acid indicated that the efficiencies decreased only after the fourth cycle of re-use. Acid-treated sugar cane bagasse can be considered a viable alternative to common methods to remove toxic metal ions from aqueous effluents of electroplating industries.

Green coconut shells were treated with acid, base and hydrogen peroxide solutions for 3, 6, 12 and 24 h for removing toxic metals from synthetic wastewater. The removal of ions by the adsorbent treated with 0.1 mol L-1 NaOH/ 3h was 99.5% for Pb2+ and 97.9% for Cu2+. The removal of Cd2+, Ni2+, Zn2+, using adsorbent treated with 1.0 mol L-1 NaOH/3 h, was 98.5, 90.3 and 95.4%, respectively. Particle size, adsorbent concentration and adsorption kinetics were also studied. An adsorbent size of 60-99 mesh and a concentration of 30-40 g/L for 5 min exposure were satisfactory for maximum uptake of Pb2+, Ni2+, Cd2+, Zn2+ and Cu2+ and can be considered as promising parameters for treatment the aqueous effluents contaminated with toxic metals.

As atividades industriais que consomem excesso de água no seu processo industrial, normalmente geram um elevado volume de efluentes, sendo a indústria têxtil um exemplo típico. A oxidação química é um dos processos alternativos para o tratamento de efluentes contendo corantes têxteis, entre eles destacam-se os processos oxidativos avançados (POAs) que são baseados na geração de radicais hidroxilas (.OH) no qual são altamente oxidantes, podendo decompor compostos de maneira rápida e não-seletiva, conduzindo a mineralização parcial ou completa do contaminante. Neste trabalho estudou-se o efeito dos ânions na degradação do corante remazol vermelho RB 133% pelo tratamento combinado H2O2/UV. Os resultados das eficiências de remoção de cor ao final do processo indicaram que não houve diferença entre os tratamentos na presença dos ânions na concentração estudada (10mM), quando comparada a degradação sem a presença desses ânions, pois ao final de todos os tratamentos a solução ficou incolor. Para o parâmetro de demanda química de oxigênio (DQO) houve influência nas eficiências de remoção dos ânions estudados, principalmente para NO3-, Cl- e PO43-.