Heavy metals contribution of non-aqueous fluids used in offshore oil drilling

A monitoring program was performed to investigate heavy metal content alteration due to exploratory drilling for oil using non-aqueous fluids (NAFs) in Brazilian offshore, 900 m deep. Fourteen elements were monitored in 54 sites and it was verified that after drilling activities the average Ba concentration was remarkably increased with respect to background level, even 1 year after the activity. A minor increase in Mn and a moderate increase in Al concentrations were verified. The Cd, Cr, Ni, As, Co, Cu, Pb, V, and Zn concentrations were at the background levels, ca. 1 year after the NAFs drilling materials deposition on the seafloor. The Al, Ba, Cd, Cr, Cu, Ni and Zn mean concentrations were significantly different (P<0.05) between the three sampling operations (cruises) performed, while As, Cd, Fe and Pb presented different mean values according to the distance of the oil well, independent of the sampling operation. Interaction between sampling operation and distance was observed for Mn. In all sediment samples the Hg concentration was below the detection limit (0.07 μg g⁻¹).     

Protective factors for iron deficiency anemia: prospective study in low-income infants

This study was performed to assess both risk and protective factors associated with iron deficiency anemia in 130 infants with age below 24 months, with low socio-economic status and followed since their births by a primary health care program in the city of S?o Paulo, Brazil. Growth, morbidity and dietary factors were analysed as well as hemoglobin levels (Hb) at regular intervals (6, 9, 12, 18 and 24 months). The portable Hemocue photometer was employed to measure hemoglobin levels and anemia was considered when Hb values were below 11 g/dL. Simple logistic regression was used with socio-economic variables, age group, nutritional status, morbidity, breastfeeding and food intake. Risk factors for anemia in the studied group were intake of cow's milk at 4 months and who has 3 or more old brothers (OR approximately = 2). The protective factors for anemia were age between 18 and 24 months and intake of infant formula, vitamin C, meat and beans at 6 months (OR approximately = 0.5). The prevention of iron deficiency anemia includes encouraging healthy feeding practices starting at 6 months of life.     

Metal Determination in Tea,Wheat, and Wheat Flour Using Diluted Nitric Acid,High-Efficiency Nebulizer,and Axially Viewed ICP OES

This study deals with the determination of Cu, Al, Cd, Mo, Pb, V, Sr, Ni, Cr, Co, Zn, Mn, and Fe in tea, wheat grain, and wheat flour by inductively coupled plasma optical emission spectrometry (ICP OES) with axially viewed plasma. Ultrasonic nebulization (USN) or pneumatic nebulization with aerosol desolvation (PN/DES) is used to introduce the sample solution into the ICP. Solutions of nitric acid (HNO₃) with different concentrations of the acid (4.6 to 9.1 mol L^?1) and hydrogen peroxide (H₂O₂) were investigated for sample decomposition in closed vessel (made of TFM-polytetrafluoroethylene (PTFE)) under microwave irradiation. Certified reference materials of tea, wheat flour, or bush branches and leaves were analyzed (0.5 g of sample in the presence of 2 mL H₂O₂?+?3 mL HNO₃?+?2 mL H₂O). Element concentrations found were in accordance with those certified in most cases, excepting for Al and V. Plasma-related matrix effects were not observed as denoted by the signal of the Ar 420.069-nm emission line. The analyte recoveries in spiked chamomile tea and wheat flour samples ranged from 87 to 107 %. By using USN, the limits of quantification (LOQs) of Cu, Al, Cd, Mo, Pb, V, Sr, Ni, Cr, Co, Zn, Mn, and Fe were 0.033, 0.006, 0.023, 0.33, 2.0, 0.33, 0.001, 0.33, 0.07, 0.033, 0.07, 0.001, and 0.02 μg g^?1, respectively. Quite similar LOQs were obtained for both nebulizers employed, with the exception of Pb; the LOQ of Pb was three times lower by using PN/DES. Commercialized tea, wheat grain, and wheat flour were analyzed, and the concentrations found were reported.     

Total Mercury, Inorganic Mercury and Methyl Mercury Determination in Red Wine

This study deals with the development of a method for total Hg, inorganic Hg and methylmercury (MeHg) determination in red wine by using flow injection-cold vapour generation–inductively coupled plasma mass spectrometry (FI-CVG-ICP-MS) and gas chromatography-ICP-MS (GC-ICP-MS). For Hg speciation analysis, a derivatization step was carried out using a 1% (m/v) sodium tetraphenylborate (NaBPh₄) solution, followed by extraction of Hg species and their quantification by GC-ICP-MS. The main parameters evaluated were the make-up gas flow rate, volume of the NaBPh₄ solution, time for derivatization reaction/analyte extraction and solvent used for Hg species extraction. Accuracy was evaluated by analyte recovery, whereas recoveries ranged from 99% to 104% for Hg(II) and MeHg. The limits of detection (LODs) for Hg(II) and MeHg were 0.77 and 0.80 μg L⁻¹, respectively. Wine from Argentina, Brazil, Chile and Uruguay were analysed. The wine samples were also acid digested for total Hg determination by FI-CVG-ICP-MS. The LOD of the method used for total Hg determination was 0.01 μg L⁻¹. The concentrations of Hg species in red wine measured by GC-ICP-MS were lower than the respective LODs. Only total Hg was detected in the analysed samples, where the highest concentration of Hg found was 0.55 ± 0.02 μg L⁻¹.     

A training course on food hygiene for butchers: measuring its effectiveness through microbiological analysis and the use of an inspection checklist

The effectiveness of food hygiene training for a group of retail butchers was evaluated with the aim of verifying whether the butchers modified their behavior in the light of knowledge gained and whether their acquired knowledge or behavior change was sustained over a period of time. Microbiological analysis (enumeration of mesophilic and coliform bacteria and Escherichia coli) of a raw semiprocessed product (stuffed rolled beef) was conducted, and an inspection checklist was issued before the training course (T0). Initial results were later compared with results obtained 1 month (T1) and 6 months (T6) after the training. The checklist comprised 89 items classified into five categories: A, approved suppliers and product reception; B, storage conditions and temperature control; C, flow process, food handling procedures, and conditions of the window display unit; D, facility design and proper cleaning and sanitizing of equipment, utensils, and work surfaces; and E, pest control system, water supply control, and garbage disposal. The inspection results were recorded as "yes" or "no" for each item. Compliance with food safety procedures was recorded as the percentage of "yes" answers. The bacterial counts were significantly higher at T0. At T6, there was no significant increase in bacterial counts. There was a significant improvement in food safety practices at T1 and T6 compared with T0 for all categories. When comparing T0 and T1, the largest increases in the compliance scores were seen within categories C and D. No significant decrease in scores for compliance with food safety practices was observed at T6. Supervision and refresher activities may be necessary to maintain behavioral changes for a longer period of time.     

Rice Slurry Analysis Using Mixed-Gas Plasma and Axially Viewed ICP OES

This study deals with determination of essential and toxic elements in slurry of rice using axially viewed inductively coupled plasma optical emission spectrometry (ICP OES) and mixed gas plasma (N₂-Ar ICP). Nitrogen was added (flow rate of 20 mL min^?1) to the nebulizer gas through the spray chamber. It was observed that the addition of N₂ increased the ICP robustness and mitigated the slurry matrix effects. Several parameters associated with the slurry preparation (extractant concentration, dispersant concentration, mass volume ratio of the slurry and sonication) were evaluated. The slurry was prepared in 10 % (m/v) HNO₃?+?0.2 % (m/v) Triton X-100. Calibration was carried out with aqueous standards whereas Y(II) (371.029 nm) was used as internal standard (IS) in order to overcome matrix effects. The IS and sample solutions were mixed online. Accuracy was evaluated by the analysis of certified reference materials and by comparison with an independent method of sample preparation (acid digestion). The concentrations were consistent with those certified or found in digested rice sample. Calcium, Mg, K, Cd Cu, Fe, Mn, Mo, Cr, Zn, Co, Pb and Ni were investigated whose limits of detections were 0.080, 0.033, 0.050, 0.048, 0.050, 0.015, 0.005, 0.107, 0.036, 0.056, 0.040, 0.367 and 0.132 mg kg^?1, respectively. The RSD (relative standard deviation) was typically lower than 10 %. Samples of parboiled, white, and brown rice were analysed and the concentrations found corroborate with those reported. It was concluded that calibration with aqueous standard is feasible, making the analysis simpler. The method is robust and can be routinely applied.     

Arsenic speciation in white wine by LC–ICP–MS

This study deals with As speciation in white wine. Arsenic species were selectively determined by liquid chromatography–inductively coupled plasma–mass spectrometry (LC–ICP–MS). Separation of As species was performed using an anion exchange column with ammonium phosphate solution (pH 6.00) as mobile phase. Samples of 14 white wine produced in South America were analysed. They were 10-fold diluted in the mobile phase prior to analysis by LC–ICP–MS. Accuracy was evaluated by recovery tests, whereas As species recovery ranged from 95% to 106%. Additionally, the sum of arsenic species concentration found by LC–ICP–MS was in agreement with the total arsenic concentration determined by ICP–MS after sample digestion. Arsenic species detected were arsenite [As(III)], arsenate [As(V)] and dimethylarsinic acid (DMA). As(III) and As(V) were detected in all analysed wine samples and DMA was detected only in wines produced in Argentina. Results for As determination in samples were from 2.9 to 10.3, 8.6 to 17.8, and <0.45 to 1.07 μg L⁻¹ for As(III), As(V) and DMA, respectively.     

Modelling the growth of Listeria monocytogenes in fresh green coconut (Cocos nucifera L.) water

The behaviour of Listeria monocytogenes in the fresh coconut water stored at 4 °C, 10 °C and 35 °C was studied. The coconut water was aseptically extracted from green coconuts (Cocos nucifera L.) and samples were inoculated in triplicate with a mixture of 5 strains of L. monocytogenes with a mean population of approximately 3 log₁₀ CFU/mL. The kinetic parameters of the bacteria were estimated from the Baranyi model, and compared with predictions of the Pathogen Modelling Program so as to predict its behaviour in the beverage. The results demonstrated that fresh green coconut water was a beverage propitious for the survival and growth of L. monocytogenes and that refrigeration at 10 °C or 4 °C retarded, but did not inhibit, growth of this bacterium. Temperature abuse at 35 °C considerably reduced the lagtimes. The study shows that L. monocytogenes growth in fresh green coconut water is controlled for several days by storage at low temperature, mainly at 4 °C. Thus, for risk population this product should only be drunk directly from the coconut or despite the sensorial alterations should be consumed pasteurized.     

Dissemination of Enterococcus faecalis and Enterococcus faecium in a Ricotta Processing Plant and Evaluation of Pathogenic and Antibiotic Resistance Profiles

In this work, the sources of contamination by Enterococcus spp. in a ricotta processing line were evaluated. The isolated strains were tested for virulence genes (gelE, cylA,B, M, esp, agg, ace, efaA, vanB), expression of virulence factors (hemolysin and gelatinase), and the resistance to 10 different antibiotics. Enterococcus faecium and Enterococcus faecalis were subjected to discriminatory identification by intergenic spacer region (ITS)‐polymerase chain reaction and sequencing of the ITS region. The results showed that Enterococcus spp. was detected in the raw materials, environment samples and the final product. None of the 107 Enterococcus isolates were completely free from all virulence genes considered. A fraction of 21.5% of the isolates containing all of the genes of the cylA, B, M operon also expressed β‐hemolysis. Most of the isolates showed the gelE gene, but only 9.3% were able to hydrolyze gelatin. In addition, 23.5% of the observed Enterococcus isolates had the vanB gene but were susceptible to vancomycin in vitro. The dissemination of antibiotic‐resistant enterococci was revealed in this study: 19.3% of the E. faecium samples and 78.0% of the E. faecalis samples were resistant to at least one of the antibiotics tested. Sequencing of region discriminated 5 and 7 distinct groups among E. faecalis and E. faecium, respectively. Although some similarity was observed among some of the isolates, all E. faecalis and E. faecium isolates had genetic differences both in the ITS region and in the virulence profile, which makes them different from each other.