Bruno Batista | Universidade Federal do ABC (original) (raw)

Papers by Bruno Batista

Research paper thumbnail of Arsenic and Rice: Toxicity, Metabolism, and Food Safety

Research paper thumbnail of A simple and practical control of the authenticity of organic sugarcane samples based on the use of machine-learning algorithms and trace elements determination by inductively coupled plasma mass spectrometry

Food Chemistry, 2015

A practical and easy control of the authenticity of organic sugarcane samples based on the use of... more A practical and easy control of the authenticity of organic sugarcane samples based on the use of machine-learning algorithms and trace elements determination by inductively coupled plasma mass spectrometry is proposed. Reference ranges for 32 chemical elements in 22 samples of sugarcane (13 organic and 9 non organic) were established and then two algorithms, Naive Bayes (NB) and Random Forest (RF), were evaluated to classify the samples. Accurate results (>90%) were obtained when using all variables (i.e., 32 elements). However, accuracy was improved (95.4% for NB) when only eight minerals (Rb, U, Al, Sr, Dy, Nb, Ta, Mo), chosen by a feature selection algorithm, were employed. Thus, the use of a fingerprint based on trace element levels associated with classification machine learning algorithms may be used as a simple alternative for authenticity evaluation of organic sugarcane samples.

Research paper thumbnail of ADESÃO AO TRATAMENTO DOS PACIENTES EM USO DE ANTIRRETROVIRAIS DE ALTA EFICIÊNCIA (TARVA) DE UBDS RP

Research paper thumbnail of Determination of total and inorganic Hg in whole blood by cold vapor inductively coupled plasma mass spectrometry with alkaline sample preparation

Research paper thumbnail of A simple method for adherence evaluation to highly active antiretroviral therapy by Brazilian patients from healthcare unit: Focus on a adequately therapeutic compliance

Research paper thumbnail of Biotransformation of arsenic oxyanions by cyanobacteria from mining areas

Research paper thumbnail of The Use of Decision Trees and Naïve Bayes Algorithms and Trace Element Patterns for Controlling the Authenticity of Free‐Range‐Pastured Hens’ Eggs

This article aims to evaluate 2 machine learning algorithms, decision trees and naïve Bayes (NB),... more This article aims to evaluate 2 machine learning algorithms, decision trees and naïve Bayes (NB), for egg classification (free-range eggs compared with battery eggs). The database used for the study consisted of 15 chemical elements (As, Ba, Cd, Co, Cs, Cu, Fe, Mg, Mn, Mo, Pb, Se, Sr, V, and Zn) determined in 52 eggs samples (20 free-range and 32 battery eggs) by inductively coupled plasma mass spectrometry. Our results demonstrated that decision trees and NB associated with the mineral contents of eggs provide a high level of accuracy (above 80% and 90%, respectively) for classification between free-range and battery eggs and can be used as an alternative method for adulteration evaluation.

Research paper thumbnail of The use of advanced chemometric techniques and trace element levels for controlling the authenticity of organic coffee

ABSTRACT This study examines the application of advanced data mining techniques associated with t... more ABSTRACT This study examines the application of advanced data mining techniques associated with trace element concentrations for authenticity evaluation of organic coffee samples. Fifty-four coffee samples (20 organic and 34 non-organic) were evaluated according to their macro and microelement contents to establish reference ranges and identify differences in patterns of chemical elements in both crop procedures. Inductively coupled plasma mass spectrometry (ICP-MS) was used for the determination of thirty-eight chemical elements (Al, As, B, Ba, Be, Bi, Cd, Ce, Co, Cr, Cs, Cu, Dy, Eu, Er, Gd, Ge, Ho, La, Lu, Mn, Mo, Ni, Pb, Rb, Se, Sm, Sr, Yb, W, U, Ta, Tb, Th, Ti, Ti, Zr and Zn). In general, higher levels of chemical elements were found in conventional coffee compared with organic samples. The classification of samples was performed by using three well known data mining algorithms, named Multilayer Perceptron (MLP), Support Vector Machine (SVM) and Naive Bayes (NB). When all analyzed variables were considered, a 96.3% accuracy level was obtained with the three algorithms. The level of accuracy remained at 96.3% for SVM and MLP and rose to 98.2 for NB when only eight of the investigated minerals - i.e. Zn, Se, Ba, U, Dy, Ti, Th, Mo - were used for chemometric analysis. This level of accuracy provides a strong foundation to propose the combination of trace element spectral fingerprints with data mining techniques as a valuable tool to evaluate the authenticity of organic coffee samples.

Research paper thumbnail of Simultaneous determination of Cd, Cu, Mn, Ni, Pb and Zn in nail samples by inductively coupled plasma mass spectrometry (ICP-MS) after tetramethylammonium hydroxide solubilization at room temperature: comparison with ETAAS

Talanta, Jan 30, 2008

A simple method is described for the determination of Cd, Cu, Mn, Ni, Pb and Zn in nails by using... more A simple method is described for the determination of Cd, Cu, Mn, Ni, Pb and Zn in nails by using inductively coupled plasma mass spectrometry (ICP-MS) or electrothermal atomic absorption spectrometry (ETAAS). Prior to analysis, 10-20 mg of nail samples were accurately weighed into (15 mL) conical tubes. Then, 1 mL of 25% (w/v) tetramethylammonium hydroxide (TMAH) solution was added to the samples, incubated at room temperature overnight and then further diluted to 10 mL with 1% (v/v) HNO(3). After that, samples were directly analyzed. Rhodium was used as internal standard for ICP-MS analysis. Method detection limits (3 s, n=20) were 0.1, 3.0, 1.0, 4.5, 1.5, 5.0 ng g(-1) for Cd, Cu, Mn, Ni, Pb and Zn, respectively for ICP-MS, and 24, 26, 30, 143, 130 and 1000 ng g(-1), respectively for ETAAS. The key issue addressed here is the elimination of the acid digestion prior to analysis. Moreover, with the use of the proposed method there is a considerable improvement in the sample throughp...

Research paper thumbnail of Determination of trace elements in biological samples by inductively coupled plasma mass spectrometry with tetramethylammonium hydroxide solubilization at room temperature

Analytica chimica acta, Jan 30, 2009

A simple method for sample preparation of biological samples for trace elements determination by ... more A simple method for sample preparation of biological samples for trace elements determination by inductively coupled plasma mass spectrometry (ICP-MS) is described. Prior to analysis, 75 mg of the biological samples were accurately weighed into (15 mL) conical tubes. Then, 1 mL of 50% (v/v) tetramethylammonium hydroxide (TMAH) solution was added to the samples, incubated at room temperature for 12 h and the volume made up to 10 mL with a solution containing 0.5% (v/v) HNO(3), 0.01% (v/v) Triton X-100 and 10 microg L(-1) of Rh. After preparation samples may be stored at -20 degrees C during 3 days until the analysis by ICP-MS. With these conditions, the use of the dynamic reaction cell was only mandatory for chromium determination. Method detection limits were 0.2145, 0.0020, 0.0051, 0.0017, 0.0027, 0.0189, 0.02, 0.5, 0.1, 0.0030, 0.0043, 0.0066, 0.0009, 0.020, 0.0043, 0.1794, 0.1 microg(-1) for Al, As, Ba, Cd, Co, Cr, Cu, Fe, Mg, Mn, Mo, Pb, Sb, Se, Sr, V and Zn, respectively. Valid...

Research paper thumbnail of Evaluation of the concentration of nonessential and essential elements in chicken, pork, and beef samples produced in Brazil

Journal of toxicology and environmental health. Part A, 2012

Food safety is a global concern. Meat represents the most important protein source for humans. Th... more Food safety is a global concern. Meat represents the most important protein source for humans. Thus, contamination of meat products by nonessential elements is a ready source of human exposure. In addition, knowledge of the concentration of essential elements is also relevant with respect to human nutrition. The aim of the present study was to determine the concentration of 17 elements in pork, beef, and chicken produced in Brazil. Meat samples were analyzed by inductively coupled plasma mass spectrometry. The estimated daily intake for nonessential elements including arsenic (As), cadmium (Cd), lead (Pb), mercury (Hg), and antimony (Sb) through meat consumption is below the toxicological reference values. However, high levels were detected for the nonessential element cesium (Cs), mainly in beef samples, an observation that deserves future studies to identify the source of contamination and potential adverse consequences.

Research paper thumbnail of Exposure to heavy metals due to pesticide use by vineyard farmers

International Archives of Occupational and Environmental Health, 2014

to seasonal conditions influencing the need for pesticide application.

Research paper thumbnail of Evaluation of human hair as a possible surrogate of whole blood and plasma to diagnose deficiency to essential elements and exposure to toxic elements

The appropriate selection and measurement of biomarkers of internal dose is of critical importanc... more The appropriate selection and measurement of biomarkers of internal dose is of critical importance. In the present study, we evaluated the relationship between trace element levels in hair with those levels in whole blood or plasma in a Brazilian population. Then, hair, blood and plasma were collected from 280 adult volunteers for metals determination. For sample analysis an ICP-MS was used. Manganese, copper, lead and strontium levels in blood varied from 5.1 to 14.7, from 494.8 to 2383.8, from 5.9 to 330.1 and from 11.6 to 87.3 g/L, respectively. Corresponding levels in hair varied from 0.05 to 6.71, from 0.02 to 37.59, from 0.02 to 30.63 and from 0.9 to 12.6 g/g. Trace element levels in plasma varied from 0.07 to 8.62, from 118.2 to 1577.7 and from 2.31 to 34.2 g/L for Mn, Cu and Sr, respectively. There was a weak association (r = 0.22, p < 0.001) between lead levels in hair with those levels in blood. Moreover, copper and strontium levels in blood correlate with those levels in plasma (r = 0.64, p < 0.001 for Cu) and (r = 0.22, p < 0.05 for Sr). However, for Cu, Mn and Sr there was no correlation between hair levels with levels in blood. Our findings suggest that while the idea of measuring trace elements in hair is attractive, hair is not an appropriate biomarker to evaluate deficiency to the essential elements Cu, Mn and Sr or the exposure to Pb.

Research paper thumbnail of Background Values for Essential and Toxic Elements in Children’s Nails and Correlation with Hair Levels

Human nails are an attractive matrix for assessing environmental exposures to toxic elements as w... more Human nails are an attractive matrix for assessing environmental exposures to toxic elements as well as the deficiency of essential elements since it is noninvasively collected and can be stored at room temperature. However, reference or baseline levels in nonexposed and healthy populations are not yet established. Then, the aims of this study were (a) to estimate background values for essential and toxic elements in nails from a healthy young population in southern Brazil and (b) to evaluate possible correlations between essential and toxic elements in nails. Furthermore, this report took part of a recent study of background values in the hair of a young population. Thus, correlations between chemical elements in nails and hair were also evaluated. Nails were collected from healthy children (n = 126), and element concentrations were determined by inductively coupled plasma mass spectrometry. This study provides new and reliable reference concentrations for toxic and essential elements in children&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;#39;s nails. The results can be used as reference values for epidemiological or clinical investigations based on trace elements in nails. Additionally, we also showed weak to strong correlations between Cu, Mg, Mn, Se, and Zn levels in nails and hair.

Research paper thumbnail of Determination of Essential (Ca, Fe, I, K, Mo) and Toxic Elements (Hg, Pb) in Brazilian Rice Grains and Estimation of Reference Daily Intake

ABSTRACT The levels of Hg and Pb (toxic elements) and Ca, Fe, I, K, Mo (essential elements) were ... more ABSTRACT The levels of Hg and Pb (toxic elements) and Ca, Fe, I, K, Mo (essential elements) were measured in 44 Brazilian rice samples divided among white polished (W), parboiled white (PW) and parboiled brown (PB). Rice grains were analyzed by inductively ...

Research paper thumbnail of Rapid sample preparation procedure for As speciation in food samples by LC-ICP-MS

This paper describes a rapid method for arsenic (As) speciation by LC-ICP-MS in several types of ... more This paper describes a rapid method for arsenic (As) speciation by LC-ICP-MS in several types of food samples. Prior to analysis, samples were milled and the As species extracted from biological tissues by sonication in only 2 min with a solution containing MeOH (10%, v/v) plus HNO₃ (2%, v/v). As species were separated by LC using an anion exchange column. Method detection limits for AsB, As³⁺, DMA, MMA and As⁵⁺ were 1.3, 0.9, 0.6, 0.7 and 0.8 ng g⁻¹, respectively. Method accuracy and precision were traceable to Certified Reference Materials SRM1577 bovine liver from the National Institute of Standards and Technology, CE278 mussel tissue from the Institute of Reference Materials and Measurements and DOLT-3 dogfish liver tissue and DORM-3 fish protein from the National Research Council of Canada. Finally, the method was applied to speciate As in food samples (egg, fish muscle, beef and chicken) purchased in Brazilian markets.

Research paper thumbnail of Multi-element determination in Brazilian honey samples by inductively coupled plasma mass spectrometry and estimation of geographic origin with data mining techniques

Research paper thumbnail of Evaluation by ICP-MS of Essential, Nonessential and Toxic Elements in Brazilian Fish and Seafood Samples

Fish is considered one of the healthiest foods due to the high levels of several important cardio... more Fish is considered one of the healthiest foods due to the high levels of several important cardioprotective compounds such as long chain omega-3 polyunsaturated fatty acids and vitamin E. However, due to widespread environmental pollution, high levels of contaminants may also be present in fish and seafood samples, which may counteract the beneficial effects of consumption of this food. With this in mind, the aims of this study were: 1) to examine both toxic and essential chemical elements in seafood and river and sea fish samples sold in different Brazilian regions by inductively coupled plasma mass spectrometer (ICP-MS); 2) to estimate the daily intake of these chemical elements by Brazilians. The toxic elements Ba, Cd, Pb, Sr, V and Sb were found in higher concentrations in seafood than in either sea or river fish, while As concentrations were higher in both seafood and sea fish than in river fish. On the other hand, Hg levels were higher in river and sea fish. Concentrations of the essential chemical elements Co, Mn, Cu, Fe, Mg, Zn and Mo were significantly higher in seafood compared with both sorts of fish except for Se, whose levels were similar in seafood and sea fish. Daily intake of all chemical elements was estimated on the basis of a calculation of the amount of fish consumed by Brazilian households (mean fish and seafood consumption of 11.0 g/person/day). The amount of toxic element in fish and seafood did not represent a risk for the Brazilian people. Moreover, fish and seafood seem to be a good source of selenium.

Research paper thumbnail of Determination of trace elements in bovine semen samples by inductively coupled plasma mass spectrometry and data mining techniques for identification of bovine class

Research paper thumbnail of Influence of processing and roasting on the antioxidant activity of cofee (Coffea arabica)

Recebido em 26/4/06; aceito em 9/8/06; publicado na web em 22/7/07 INFLUENCE OF PROCESSING AND RO... more Recebido em 26/4/06; aceito em 9/8/06; publicado na web em 22/7/07 INFLUENCE OF PROCESSING AND ROASTING ON THE ANTIOXIDANT ACTIVITY OF COFFEE (Coffea arabica). The aim of this work is to evaluate the influence of processing (semi-dry and dry) and roasting (light, medium and dark) on the antioxidant activity of coffee brews, using tests to determine the reducing power and the DPPH scavenging, Fe +2 chelating and lipid peroxidation inhibition activities. All of the coffee brews presented concentration-dependent antioxidant activity. The light coffee samples presented the higher reducing power and DPPH scavenging activity. Its ion chelating capacity was similar to the medium samples, but was less than the green coffee chelating capacity. The semi-dry processing was more efficient than the dry processing only for the reducing power. All of the samples presented high lipid peroxidation inhibition activity. Based on the results the degree of coffee roasting seems to be more important than the processing to determine the antioxidant activity of brews.

Research paper thumbnail of Arsenic and Rice: Toxicity, Metabolism, and Food Safety

Research paper thumbnail of A simple and practical control of the authenticity of organic sugarcane samples based on the use of machine-learning algorithms and trace elements determination by inductively coupled plasma mass spectrometry

Food Chemistry, 2015

A practical and easy control of the authenticity of organic sugarcane samples based on the use of... more A practical and easy control of the authenticity of organic sugarcane samples based on the use of machine-learning algorithms and trace elements determination by inductively coupled plasma mass spectrometry is proposed. Reference ranges for 32 chemical elements in 22 samples of sugarcane (13 organic and 9 non organic) were established and then two algorithms, Naive Bayes (NB) and Random Forest (RF), were evaluated to classify the samples. Accurate results (&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;gt;90%) were obtained when using all variables (i.e., 32 elements). However, accuracy was improved (95.4% for NB) when only eight minerals (Rb, U, Al, Sr, Dy, Nb, Ta, Mo), chosen by a feature selection algorithm, were employed. Thus, the use of a fingerprint based on trace element levels associated with classification machine learning algorithms may be used as a simple alternative for authenticity evaluation of organic sugarcane samples.

Research paper thumbnail of ADESÃO AO TRATAMENTO DOS PACIENTES EM USO DE ANTIRRETROVIRAIS DE ALTA EFICIÊNCIA (TARVA) DE UBDS RP

Research paper thumbnail of Determination of total and inorganic Hg in whole blood by cold vapor inductively coupled plasma mass spectrometry with alkaline sample preparation

Research paper thumbnail of A simple method for adherence evaluation to highly active antiretroviral therapy by Brazilian patients from healthcare unit: Focus on a adequately therapeutic compliance

Research paper thumbnail of Biotransformation of arsenic oxyanions by cyanobacteria from mining areas

Research paper thumbnail of The Use of Decision Trees and Naïve Bayes Algorithms and Trace Element Patterns for Controlling the Authenticity of Free‐Range‐Pastured Hens’ Eggs

This article aims to evaluate 2 machine learning algorithms, decision trees and naïve Bayes (NB),... more This article aims to evaluate 2 machine learning algorithms, decision trees and naïve Bayes (NB), for egg classification (free-range eggs compared with battery eggs). The database used for the study consisted of 15 chemical elements (As, Ba, Cd, Co, Cs, Cu, Fe, Mg, Mn, Mo, Pb, Se, Sr, V, and Zn) determined in 52 eggs samples (20 free-range and 32 battery eggs) by inductively coupled plasma mass spectrometry. Our results demonstrated that decision trees and NB associated with the mineral contents of eggs provide a high level of accuracy (above 80% and 90%, respectively) for classification between free-range and battery eggs and can be used as an alternative method for adulteration evaluation.

Research paper thumbnail of The use of advanced chemometric techniques and trace element levels for controlling the authenticity of organic coffee

ABSTRACT This study examines the application of advanced data mining techniques associated with t... more ABSTRACT This study examines the application of advanced data mining techniques associated with trace element concentrations for authenticity evaluation of organic coffee samples. Fifty-four coffee samples (20 organic and 34 non-organic) were evaluated according to their macro and microelement contents to establish reference ranges and identify differences in patterns of chemical elements in both crop procedures. Inductively coupled plasma mass spectrometry (ICP-MS) was used for the determination of thirty-eight chemical elements (Al, As, B, Ba, Be, Bi, Cd, Ce, Co, Cr, Cs, Cu, Dy, Eu, Er, Gd, Ge, Ho, La, Lu, Mn, Mo, Ni, Pb, Rb, Se, Sm, Sr, Yb, W, U, Ta, Tb, Th, Ti, Ti, Zr and Zn). In general, higher levels of chemical elements were found in conventional coffee compared with organic samples. The classification of samples was performed by using three well known data mining algorithms, named Multilayer Perceptron (MLP), Support Vector Machine (SVM) and Naive Bayes (NB). When all analyzed variables were considered, a 96.3% accuracy level was obtained with the three algorithms. The level of accuracy remained at 96.3% for SVM and MLP and rose to 98.2 for NB when only eight of the investigated minerals - i.e. Zn, Se, Ba, U, Dy, Ti, Th, Mo - were used for chemometric analysis. This level of accuracy provides a strong foundation to propose the combination of trace element spectral fingerprints with data mining techniques as a valuable tool to evaluate the authenticity of organic coffee samples.

Research paper thumbnail of Simultaneous determination of Cd, Cu, Mn, Ni, Pb and Zn in nail samples by inductively coupled plasma mass spectrometry (ICP-MS) after tetramethylammonium hydroxide solubilization at room temperature: comparison with ETAAS

Talanta, Jan 30, 2008

A simple method is described for the determination of Cd, Cu, Mn, Ni, Pb and Zn in nails by using... more A simple method is described for the determination of Cd, Cu, Mn, Ni, Pb and Zn in nails by using inductively coupled plasma mass spectrometry (ICP-MS) or electrothermal atomic absorption spectrometry (ETAAS). Prior to analysis, 10-20 mg of nail samples were accurately weighed into (15 mL) conical tubes. Then, 1 mL of 25% (w/v) tetramethylammonium hydroxide (TMAH) solution was added to the samples, incubated at room temperature overnight and then further diluted to 10 mL with 1% (v/v) HNO(3). After that, samples were directly analyzed. Rhodium was used as internal standard for ICP-MS analysis. Method detection limits (3 s, n=20) were 0.1, 3.0, 1.0, 4.5, 1.5, 5.0 ng g(-1) for Cd, Cu, Mn, Ni, Pb and Zn, respectively for ICP-MS, and 24, 26, 30, 143, 130 and 1000 ng g(-1), respectively for ETAAS. The key issue addressed here is the elimination of the acid digestion prior to analysis. Moreover, with the use of the proposed method there is a considerable improvement in the sample throughp...

Research paper thumbnail of Determination of trace elements in biological samples by inductively coupled plasma mass spectrometry with tetramethylammonium hydroxide solubilization at room temperature

Analytica chimica acta, Jan 30, 2009

A simple method for sample preparation of biological samples for trace elements determination by ... more A simple method for sample preparation of biological samples for trace elements determination by inductively coupled plasma mass spectrometry (ICP-MS) is described. Prior to analysis, 75 mg of the biological samples were accurately weighed into (15 mL) conical tubes. Then, 1 mL of 50% (v/v) tetramethylammonium hydroxide (TMAH) solution was added to the samples, incubated at room temperature for 12 h and the volume made up to 10 mL with a solution containing 0.5% (v/v) HNO(3), 0.01% (v/v) Triton X-100 and 10 microg L(-1) of Rh. After preparation samples may be stored at -20 degrees C during 3 days until the analysis by ICP-MS. With these conditions, the use of the dynamic reaction cell was only mandatory for chromium determination. Method detection limits were 0.2145, 0.0020, 0.0051, 0.0017, 0.0027, 0.0189, 0.02, 0.5, 0.1, 0.0030, 0.0043, 0.0066, 0.0009, 0.020, 0.0043, 0.1794, 0.1 microg(-1) for Al, As, Ba, Cd, Co, Cr, Cu, Fe, Mg, Mn, Mo, Pb, Sb, Se, Sr, V and Zn, respectively. Valid...

Research paper thumbnail of Evaluation of the concentration of nonessential and essential elements in chicken, pork, and beef samples produced in Brazil

Journal of toxicology and environmental health. Part A, 2012

Food safety is a global concern. Meat represents the most important protein source for humans. Th... more Food safety is a global concern. Meat represents the most important protein source for humans. Thus, contamination of meat products by nonessential elements is a ready source of human exposure. In addition, knowledge of the concentration of essential elements is also relevant with respect to human nutrition. The aim of the present study was to determine the concentration of 17 elements in pork, beef, and chicken produced in Brazil. Meat samples were analyzed by inductively coupled plasma mass spectrometry. The estimated daily intake for nonessential elements including arsenic (As), cadmium (Cd), lead (Pb), mercury (Hg), and antimony (Sb) through meat consumption is below the toxicological reference values. However, high levels were detected for the nonessential element cesium (Cs), mainly in beef samples, an observation that deserves future studies to identify the source of contamination and potential adverse consequences.

Research paper thumbnail of Exposure to heavy metals due to pesticide use by vineyard farmers

International Archives of Occupational and Environmental Health, 2014

to seasonal conditions influencing the need for pesticide application.

Research paper thumbnail of Evaluation of human hair as a possible surrogate of whole blood and plasma to diagnose deficiency to essential elements and exposure to toxic elements

The appropriate selection and measurement of biomarkers of internal dose is of critical importanc... more The appropriate selection and measurement of biomarkers of internal dose is of critical importance. In the present study, we evaluated the relationship between trace element levels in hair with those levels in whole blood or plasma in a Brazilian population. Then, hair, blood and plasma were collected from 280 adult volunteers for metals determination. For sample analysis an ICP-MS was used. Manganese, copper, lead and strontium levels in blood varied from 5.1 to 14.7, from 494.8 to 2383.8, from 5.9 to 330.1 and from 11.6 to 87.3 g/L, respectively. Corresponding levels in hair varied from 0.05 to 6.71, from 0.02 to 37.59, from 0.02 to 30.63 and from 0.9 to 12.6 g/g. Trace element levels in plasma varied from 0.07 to 8.62, from 118.2 to 1577.7 and from 2.31 to 34.2 g/L for Mn, Cu and Sr, respectively. There was a weak association (r = 0.22, p < 0.001) between lead levels in hair with those levels in blood. Moreover, copper and strontium levels in blood correlate with those levels in plasma (r = 0.64, p < 0.001 for Cu) and (r = 0.22, p < 0.05 for Sr). However, for Cu, Mn and Sr there was no correlation between hair levels with levels in blood. Our findings suggest that while the idea of measuring trace elements in hair is attractive, hair is not an appropriate biomarker to evaluate deficiency to the essential elements Cu, Mn and Sr or the exposure to Pb.

Research paper thumbnail of Background Values for Essential and Toxic Elements in Children’s Nails and Correlation with Hair Levels

Human nails are an attractive matrix for assessing environmental exposures to toxic elements as w... more Human nails are an attractive matrix for assessing environmental exposures to toxic elements as well as the deficiency of essential elements since it is noninvasively collected and can be stored at room temperature. However, reference or baseline levels in nonexposed and healthy populations are not yet established. Then, the aims of this study were (a) to estimate background values for essential and toxic elements in nails from a healthy young population in southern Brazil and (b) to evaluate possible correlations between essential and toxic elements in nails. Furthermore, this report took part of a recent study of background values in the hair of a young population. Thus, correlations between chemical elements in nails and hair were also evaluated. Nails were collected from healthy children (n = 126), and element concentrations were determined by inductively coupled plasma mass spectrometry. This study provides new and reliable reference concentrations for toxic and essential elements in children&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;#39;s nails. The results can be used as reference values for epidemiological or clinical investigations based on trace elements in nails. Additionally, we also showed weak to strong correlations between Cu, Mg, Mn, Se, and Zn levels in nails and hair.

Research paper thumbnail of Determination of Essential (Ca, Fe, I, K, Mo) and Toxic Elements (Hg, Pb) in Brazilian Rice Grains and Estimation of Reference Daily Intake

ABSTRACT The levels of Hg and Pb (toxic elements) and Ca, Fe, I, K, Mo (essential elements) were ... more ABSTRACT The levels of Hg and Pb (toxic elements) and Ca, Fe, I, K, Mo (essential elements) were measured in 44 Brazilian rice samples divided among white polished (W), parboiled white (PW) and parboiled brown (PB). Rice grains were analyzed by inductively ...

Research paper thumbnail of Rapid sample preparation procedure for As speciation in food samples by LC-ICP-MS

This paper describes a rapid method for arsenic (As) speciation by LC-ICP-MS in several types of ... more This paper describes a rapid method for arsenic (As) speciation by LC-ICP-MS in several types of food samples. Prior to analysis, samples were milled and the As species extracted from biological tissues by sonication in only 2 min with a solution containing MeOH (10%, v/v) plus HNO₃ (2%, v/v). As species were separated by LC using an anion exchange column. Method detection limits for AsB, As³⁺, DMA, MMA and As⁵⁺ were 1.3, 0.9, 0.6, 0.7 and 0.8 ng g⁻¹, respectively. Method accuracy and precision were traceable to Certified Reference Materials SRM1577 bovine liver from the National Institute of Standards and Technology, CE278 mussel tissue from the Institute of Reference Materials and Measurements and DOLT-3 dogfish liver tissue and DORM-3 fish protein from the National Research Council of Canada. Finally, the method was applied to speciate As in food samples (egg, fish muscle, beef and chicken) purchased in Brazilian markets.

Research paper thumbnail of Multi-element determination in Brazilian honey samples by inductively coupled plasma mass spectrometry and estimation of geographic origin with data mining techniques

Research paper thumbnail of Evaluation by ICP-MS of Essential, Nonessential and Toxic Elements in Brazilian Fish and Seafood Samples

Fish is considered one of the healthiest foods due to the high levels of several important cardio... more Fish is considered one of the healthiest foods due to the high levels of several important cardioprotective compounds such as long chain omega-3 polyunsaturated fatty acids and vitamin E. However, due to widespread environmental pollution, high levels of contaminants may also be present in fish and seafood samples, which may counteract the beneficial effects of consumption of this food. With this in mind, the aims of this study were: 1) to examine both toxic and essential chemical elements in seafood and river and sea fish samples sold in different Brazilian regions by inductively coupled plasma mass spectrometer (ICP-MS); 2) to estimate the daily intake of these chemical elements by Brazilians. The toxic elements Ba, Cd, Pb, Sr, V and Sb were found in higher concentrations in seafood than in either sea or river fish, while As concentrations were higher in both seafood and sea fish than in river fish. On the other hand, Hg levels were higher in river and sea fish. Concentrations of the essential chemical elements Co, Mn, Cu, Fe, Mg, Zn and Mo were significantly higher in seafood compared with both sorts of fish except for Se, whose levels were similar in seafood and sea fish. Daily intake of all chemical elements was estimated on the basis of a calculation of the amount of fish consumed by Brazilian households (mean fish and seafood consumption of 11.0 g/person/day). The amount of toxic element in fish and seafood did not represent a risk for the Brazilian people. Moreover, fish and seafood seem to be a good source of selenium.

Research paper thumbnail of Determination of trace elements in bovine semen samples by inductively coupled plasma mass spectrometry and data mining techniques for identification of bovine class

Research paper thumbnail of Influence of processing and roasting on the antioxidant activity of cofee (Coffea arabica)

Recebido em 26/4/06; aceito em 9/8/06; publicado na web em 22/7/07 INFLUENCE OF PROCESSING AND RO... more Recebido em 26/4/06; aceito em 9/8/06; publicado na web em 22/7/07 INFLUENCE OF PROCESSING AND ROASTING ON THE ANTIOXIDANT ACTIVITY OF COFFEE (Coffea arabica). The aim of this work is to evaluate the influence of processing (semi-dry and dry) and roasting (light, medium and dark) on the antioxidant activity of coffee brews, using tests to determine the reducing power and the DPPH scavenging, Fe +2 chelating and lipid peroxidation inhibition activities. All of the coffee brews presented concentration-dependent antioxidant activity. The light coffee samples presented the higher reducing power and DPPH scavenging activity. Its ion chelating capacity was similar to the medium samples, but was less than the green coffee chelating capacity. The semi-dry processing was more efficient than the dry processing only for the reducing power. All of the samples presented high lipid peroxidation inhibition activity. Based on the results the degree of coffee roasting seems to be more important than the processing to determine the antioxidant activity of brews.