Análisis de flexión en alambres de níquel-titanio con y sin propiedades de transformación térmica / Bending analysis of nickel-titanium wires with and no thermal transformation properties

Objetivo: Evaluar el comportamiento de los alambres de aleación de níquel-titanio con y sin propiedades de transformación térmica en la relación carga/deflexión. Materiales y método: Para ello, 30 segmentos de alambres de níquel-titanio con calibre .014" y 30 mm de largo fueron cortados, conformando 10 segmentos de alambre Flexy NiTi de Orthometric®, 10 segmentos Flexy Copper NiTi termoactivado y 10 segmentos CuNiTi de OrmcoTM. Se usó una máquina universal de ensayos Instron® para analizar el comportamiento de carga y deflexión de los segmentos en una prueba de tres puntos, registrando las fuerzas alcanzadas en 0,5 mm: 1 mm, 2 mm y 4 mm de deflexión. Resultados: Hubo una diferencia estadísticamente significativa entre todos los alambres y entre todas las deflexiones, ya que el alambre Flexy Cooper NiTi presentó la menor carga entre todas las deflexiones analizadas. Conclusión: Se concluye que los alambres termoactivados alcanzan fuerzas más leves, lo que los hace más apropiados para alineaciones iniciales, las cuales requieren un mayor rango de deflexión(AU)

Evaluation of nickel and cobalt release from mobile phone devices used in Brazil

Abstract: Nickel and cobalt are often responsible for metal-induced allergic contact dermatitis. With the increasing use of cell phones, we observed an increase in cases reports on telephone-related allergic contact dermatitis. The present study evaluated nickel and cobalt release from mobile phones used in Brazil. We evaluated devices of 6 brands and 20 different models using nickel and cobalt allergy spot tests. Of the 20 models, 64.7% tested positive for nickel, with 41.1% positive results for the charger input and 23.5% for other tested areas. None of them was positive for cobalt. Nickel release was more common in older models.

Comparison Between Nickel and Chromium Levels in Serum and Urine in Patients Treated with Fixed Orthodontic Appliances: A Longitudinal Study

Objective: To compare levels of nickel and chromium in serum and urine in orthodontic patients treated with fixed orthodontic appliances. Material and Methods: Nickel and chromium ion concentration were measured in serum and urine of twenty patients (12 females and 8 males, aged 17-28 years old) who had fixed orthodontic treatment using Coupled Plasma-Atomic Emission Spectroscopy. The samples were taken before treatment (Baseline), two months, and six months later during treatment. Data were analyzed using repeated ANOVA, Bonferroni post-hoc test, and paired t-tests. The level of significance was set at 5%. Results: Average serum nickel level changed from 6.420 ppb to 6.855 ppb. Average serum chromium level changed from 5.305 ppb to 5.505 ppb in 6 months. Average urinary nickel level changed from 5.320 ppb to 5.610 ppb. Average urinary chromium level changed from 5.370 ppb to 5.520 ppb in 6 months. There was a statistically significant difference in serum (p<0.001) and urinary chromium (p=0.007) levels between observation times. Conclusion: Orthodontic treatment might raise both urinary and serum nickel levels, but the differences were not statistically significant; the alterations in chromium levels were not consistent; nickel levels were higher in serum than in urine; chromium levels were higher in urine than in serum.

Nickel exposure from keys: a Brazilian issue

Abstract: Keys are a significant source of exposure to metal allergens and can be a relevant problem for nickel-allergic individuals. This study aimed to perform nickel and cobalt spot testing among the 5 most common Brazilian brands of keys. Among the tested keys, 100% showed positive result to nickel spot test, 83,3% presented strong positive reaction. 50% exhibited cobalt release as well. Nickel release from keys is very common in our country and may cause a negative impact on sensitized individual's quality of life. Study's results highlight the importance of establishing directives to regulate nickel release in Brazil.

Análise qualitativa da estrutura química de quatro marcas comerciais de implantes dentários brasileiros: Estudo-piloto / Qualitative analysis of the chemical composition of four Brazilian dental implant manufacturers: a pilot study

Objetivo: avaliar qualitativamente a estrutura química de quatro marcas comerciais de implantes dentários brasileiros. Material e métodos: 12 amostras de diferentes lotes foram fixadas em resina acrílica usando um processo padronizado, e cortes sagitais foram realizados. As amostras foram analisadas em dois microscópios eletrônicos de varredura (FEI Quanta 400, TM 3030 Plus Tablestop Microscope Hitachi). Resultados: a maioria apresentou na sua porção interna (8 das 12) diferentes níveis de níquel, variando de uma marca para outra. Entretanto, este metal não foi detectado na superfície externa. A presença de níquel talvez seja atribuída às matérias-primas e metodologia de produção, desde a sua extração até a comercialização. Conclusão: dentro dos limites desta investigação, há necessidade de mais estudos qualitativos, em todo o processo de fabricação de todos os implantes comercializados, assim como estudos quantitativos com relação ao elemento níquel nos implantes dentários.

Objective: to perform a qualitative evaluation of the chemical structure of four commercial dental implant Brazilian brands. Material and methods: 12 samples of different batches were embedded in acrylic resin according to a standardized process, and sagittal sections were made accordingly. All the samples were analyzed under two SEM devices (FEI Quanta 400, TM 3030 Plus Tablestop Microscope Hitachi). Results: most samples (8 of 12) revealed at their internal portions different levels of Nickel, from one manufacturer to the other. However, this metal was not detected at the external implant portion. The presence of Nickel maybe can be attributed to the raw materials and production process, from extraction to commercialization. Conclusion: within the limits of this investigation, more qualitative studies are necessary throughout the fabrication process of all investigated implants in the market, as well as quantitative evaluations regarding the presence of Nickel on dental implants.

Bioacumulación de níquel en encía, saliva y hueso alveolar de paciente con aparatología ortodóncica fija: reporte de un caso / Bioaccumulation of nickel in gingiva, saliva and alveolar bone in a patient with a fixed orthodontic appliance: a case report

Se presenta el caso de una paciente de 28 años, con tratamiento ortodóncico activo, que acudió a consulta odontológica por motivos estéticos. Luego del examen intraoral se le diagnosticó agrandamiento gingival y exostosis maxilar. El plan de tratamiento consistió en cirugía estética periodontal y exéresis de la exostosis. Durante el tratamiento quirúrgico se tomaron muestras de encía, saliva y hueso alveolar, previo consentimiento informado. Una vez procesadas las muestras se midieron las concentraciones de níquel en ng/ml mediante espectrofotometría de absorción atómica; el promedio de dichas concentraciones en cada una de las muestras fueron: 986,4 ng/ml en saliva, 779,5 ng/ml en hueso y 620,5 ng/ml para el caso de la encía. La acumulación de níquel evidenciada en cada una de las muestras resulta de especial interés, pues la exposición a metales contenidos en la aparatología ortodóncica constituye actualmente un importante tema de investigación.

A case is reported of a 28-year-old female patient, with active orthodontic treatment, who was treated in the dental practice for aesthetic reasons. The diagnosis was gingival overgrowth, induced by orthodontic treatment, and maxillary exostosis. The treatment consisted of periodontal cosmetic surgery and removing the exostosis. During surgery, samples of gingiva, saliva and alveolar bone were obtained. Before take the samples, the patient signed an informed consent. Nickel concentrations in ng/mL were measured by atomic absorption spectrophotometry. The mean nickel concentration in the samples were: 986.4 ng/ml in saliva, 779.5 ng/ml in alveolar bone, and 620.5 ng/ml in the case of gingiva. The high accumulation of nickel observed in each sample type is of particular interest because exposure to metals contained in orthodontic appliances is currently an important public health problem in dentistry.

Níquel en cavidad oral de individuos con agrandamiento gingival inducido por tratamiento ortodóncico / Nickel in oral cavity of individuals with gingival overgrowth induced by orthodontic treatment

El agrandamiento gingival es una de las alteraciones orales generadas por el uso de aparatología ortodóncica fija. Inicialmente fue descrito como producto de la respuesta alérgica del huésped al níquel, y estudios recientes demostraron que este metal induce proliferación fibroblástica. Sin embargo, se desconoce el grado de bioacumulación de este metal en la cavidad oral. El objetivo del presente estudio consistió en cuantificar la concentración de níquel en muestras de saliva, placa dental y encía de individuos con aparatología ortodóncica fija con y sin agrandamiento gingival. El tamaño de la muestra se estableció según tendencia histórica, evaluando un total de 24 individuos con tratamiento ortodóncico activo, los cuales fueron clasificados en 2 grupos: 12 con agrandamiento gingival (grupo A) y 12 sin agrandamiento gingival (grupo B). De cada participante se obtuvieron muestras de: encía, saliva estimulada y placa dental. Una vez procesadas las muestras se midieron las concentraciones de níquel en mg/l, mediante espectrofotometría de absorción atómica (Thermo Scientific. Atomic absorption spectrometer iCE 3000, Reino Unido). El análisis estadístico se realizó mediante el software SPSS v20. Al comparar los niveles de níquel en muestras de saliva estimulada, placa dental y encía entre los individuos con y sin agrandamiento gingival, se observaron niveles significativamente mayores de níquel en las muestras de encía del grupo A (medias = 0,61 mg/l vs 0,36 mg/l; p = 0,001). Sin embargo, no se observó diferencia estadísticamente significativa al comparar las concentraciones de Ni en saliva entre el grupo A y B (medias = 0,502 mg/l vs 0,473 mg/l; p = 0,178, respectivamente). A partir de estos resultados se concluye que el uso de aparatología ortodóncica fija conlleva distintos niveles de bioacumulación de iones níquel en la encía al comparar ambos grupos. Es probable que altas concentraciones de este metal estén relacionadas con la etiología del agrandamiento gingival, por lo que se requieren nuevos estudios para establecer causalidad.

Gingival overgrowth is an oral condition generated by the use of fixed orthodontic appliances. It was initially described as a product of the allergic response of the host to Nickel, and recent studies showed that this metal induces fibroblast proliferation. However, the degree of bioaccumulation of this metal in the oral cavity is unknown. The aim of this study was to quantify the concentrations of nickel in samples of saliva, dental plaque, and gingiva of individuals with fixed orthodontic appliances with and without gingival overgrowth. The sample size was established according to historical trends, evaluating 24 individuals with active orthodontic treatment, which were classified in two groups: 12 with gingival overgrowth (Group A) and 12 without gingival overgrowth (Group B). Samples of gingival, stimulated saliva and dental plaque were obtained from each participant. Once the sample were processed, nickel concentrations were measured in [mg/L] by atomic absorption spectrophotometry (Thermo Scientific. Atomic absorption spectrometer iCE 3000, UK). Statistical analysis was performed using SPSS v20. The levels of Nickel in samples of stimulated saliva, dental plaque and gingiva were compared between individuals in group A and group B. There were significantly higher levels of nickel in gingiva samples in group A (mean = 0.61 mg/L vs. 0.36 mg/L, P = .001). However, no statistical difference was observed when comparing the concentrations of nickel in saliva between groups A and B (mean = 0.502 mg/L vs. 0.473 mg/L, P = .178, respectively). The use of fixed orthodontic appliances leads to different levels of bioaccumulation of nickel in gingiva when comparing both groups. High concentrations of this metal are probably associated with the origin of gingival overgrowth. Further studies are required to establish causation.

Physicochemical properties of some bottled water brands in Alexandria governorate, Egypt

Many people use bottled water instead of tap water for many reasons such as taste, ease of carrying, and thinking that it is safer than tap water. Irrespective of the reason, bottled water consumption has been steadily growing in the world for the past 30 years. In Egypt, this is still increasing to reach 3.8 l/person/day, despite its high price compared with tap water. The purpose of this study was to evaluate the physicochemical quality of some bottled water brands and to compare the quality with that reported on manufacture's labeling, Egyptian, and International standards. Fourteen bottled water brands were selected from the local markets of Alexandria city. Three bottles from each brand were randomly sampled, making a total sample size of 42 bottles. Sampling occurred between July 2012 and September 2012. Each bottle was analyzed for its physicochemical parameter and the average was calculated for each brand. The results obtained were compared with the Egyptian standard for bottled water, Food and Drug Administration [FDA], and with bottled water labels. In all bottles in the study, pH values ranged between 7.21 and 8.23, conductivity ranged between 195 and 675 micro s/cm, and total dissolved solids, sulfate, chloride, and fluoride were within the range specified by the FDA. Calcium concentrations ranged between 2.7373 and 29.2183 mg/l, magnesium concentrations ranged between 5.7886 and 17.6633 mg/l, sodium between 14.5 and 205.8 mg/l, and potassium between 6.5 and 29.8 mg/l. For heavy metals such as iron, zinc, copper, and manganese, all of them were in conformity with the Egyptian standards and FDA, but nickel concentration in 11 brands was higher than the Egyptian standards. Twelve brands were higher than the Egyptian standards in cadmium concentration, but on comparison with FDA there were only five brands exceeding limits. Lead concentrations were out of range for all brands. On comparison with the labeled values, the quality of bottled water was not complying with labeled values. Physicochemical parameters in all bottled water examined brands were consistent with the Egyptian Standard and FDA, except for total dissolved solids, nickel, cadmium, and lead. Statistical analysis showed that there was significant difference [P<0.05] in all parameters tested between different brands. Values on the bottled water labels were not in agreement with analytical results

Nickel and chromium levels in the saliva of a Saudi sample treated with fixed orthodontic appliances

The aim of this study was to measure the amount of nickel [Ni] and chromium [Cr] released into the saliva of Saudi patients treated with fixed orthodontic appliances. Ninety salivary samples were collected in a cross-sectional manner. Forty samples were collected from patients [17 males, 23 females] with fixed orthodontic appliances after different periods of orthodontic treatment ranging from the first month and up to 32 months into treatment. The fixed orthodontic appliance consisted of 4 bands, 20 stainless steel brackets, and upper and lower nickel titanium or stainless-steel arch wires. The other 50 samples were collected from people without appliances [24 males, 26 females]. Samples were analyzed using Inductive Coupled Plasma/Mass Spectrometry and Inductively Coupled Plasma Optical Emission Spectroscopy to measure Ni and Cr levels, respectively. Student's t-test was used to compare Ni and Cr levels in the treated and untreated control groups. The mean Ni level was 4.197 microg/L in the experimental group and 2.3 ug/L in the control group [p < 0.05]. The mean Cr level was 2.9 microg/L in the experimental group and 3.3 microg/L in the control group [p < 0.05]. Fixed orthodontic appliances resulted in a non-toxic increase in salivary levels of Ni, but no change in Cr levels. Duration of orthodontic treatment did not affect Ni and Cr levels in the saliva

Eficiência de corte de diferentes sistemas endodônticos de NiTi / Cutting efficiency of rotary NiTi instruments

As características geométricas dos instrumentos de NiTi influenciam diretamente a sua eficiência de corte. Neste estudo avaliou-se o corte de instrumentos rotatórios de NiTi de calibre 20, taper .06, dos sistemas EndoSequence (ES), Mtwo, GT, GTX, K3, RaCe e ProTaper F1 (F1). Inicialmente, os instrumentos foram caracterizados com relação ao diâmetro da parte ativa, geometria da seção transversal e ãngulos helocoidais e de corte. Os ensaios de eficiência de corte foram realizados em dispositivo de bancada, onde 5 instrumentos de cada tipo foram testados em blocos de acrílico pré-fabricados, contendo um canal artificial previamente explorado com limas manuais #10 e #15...

Effect of denture cleansers on metal ion release and surface roughness of denture base materials

Chemical disinfectants are usually associated with mechanical methods to remove stains and reduce biofilm formation. This study evaluated the effect of disinfectants on release of metal ions and surface roughness of commercially pure titanium, metal alloys, and heat-polymerized acrylic resin, simulating 180 immersion trials. Disk-shaped specimens were fabricated with commercially pure titanium (Tritan), nickel-chromium-molybdenum-titanium (Vi-Star), nickel-chromium (Fit Cast-SB Plus), and nickel-chromium-beryllium (Fit Cast-V) alloys. Each cast disk was invested in the flasks, incorporating the metal disk to the heat-polymerized acrylic resin. The specimens (n=5) were immersed in these solutions: sodium hypochlorite 0.05%, Periogard, Cepacol, Corega Tabs, Medical Interporous, and Polident. Deionized water was used as a control. The quantitative analysis of metal ion release was performed using inductively coupled plasma mass spectrometry (ELAN DRC II). A surface analyzer (Surftest SJ-201P) was used to measure the surface roughness (µm). Data were recorded before and after the immersions and evaluated by two-way ANOVA and Tukey's test (α=0.05). The nickel release proved most significant with the Vi-Star and Fit Cast-V alloys after immersion in Medical Interporous. There was a significant difference in surface roughness of the resin (p=0.011) after immersion. Cepacol caused significantly higher resin roughness. The immersion products had no influence on metal roughness (p=0.388). It could be concluded that the tested alloys can be considered safe for removable denture fabrication, but disinfectant solutions as Cepacol and Medical Interporous tablet for daily denture immersion should be used with caution because it caused greater resin surface roughness and greater ion release, respectively.

Desinfetantes químicos são normalmente associados a métodos mecânicos para remover manchas e reduzir a formação do biofilme. Este estudo avaliou o efeito de desinfetantes na liberação de íons metálicos e na rugosidade superficial do titânio comercialmente puro, ligas metálicas e resina acrílica termopolimerizável, simulando 180 ensaios de imersões. Espécimes em formato de discos foram confeccionados com titânio comercialmente puro (Tritan), liga de níquel-cromo-molibdênio-titânio (Vi-Star), liga de níquel-cromo (Fit Cast-SB Plus) e liga de níquel-cromo-berílio (Fit Cast-V). Os espécimes (n=5) foram imersos nestas soluções: hipoclorito de sódio a 0,05%, Periogard, Cepacol, Corega Tabs, Medical Interporous e Polident. Como controle, foi utilizada a água deionizada. A análise quantitativa de liberação de íons metálicos foi realizada por meio de espectrometria de massa com plasma indutivamente acoplado (ELAN DRC II). O rugosímetro (Surftest SJ-201P) foi utilizado para medir a rugosidade superficial (µm). Os dados foram registrados antes e depois das imersões e avaliados por ANOVA com dois fatores e teste de Tukey (α=0,05). A liberação de níquel provou ser mais expressiva nas ligas Vi-Star e Fit Cast-V após a imersão em Medical Interporous. Houve diferença significante na rugosidade superficial da resina (p=0,011) após a imersão. O Cepacol causou maior rugosidade superficial de forma significativa. Os produtos de imersão não influenciaram nos resultados da rugosidade do metal (p=0,388). Pode-se concluir que as ligas metálicas testadas podem ser consideradas seguras para a fabricação de próteses removíveis, mas as soluções desinfetantes como o Cepacol e a pastilha Medical Interporous para a imersão diária da prótese devem ser utilizados com cautela, pois causaram maior rugosidade superficial da resina e maior liberação de íons, respectivamente.

Efectos sobre la salud y el medio ambiente de las actividades mineras en Chile: contaminación del Estero Pupío y agua potable del pueblo de Caimanes: ¿se origina desde el tranque de relaves mineros El Mauro? / Health and environmental effects of mining activities in Chile: Pupio River and Ddinking water pollution in the town of Caimanes: does it originate from the El Mauro mining tail?

Se describe la presencia de concentraciones elevadas de mercurio en el agua potable del pueblo de Caimanes y la presencia de concentraciones muy elevadas de manganeso, mercurio, hierro, níquel y molibdeno en el estero Pupío. La evidencia sugiere que estos niveles elevados de elementos tóxicos provienen de filtraciones del tranque de relaves El Mauro en la IV Región de Chile. Se describen los efectos diferidos de la exposición crónica y prenatal a estos elementos tóxicos.

The presence of high amounts of mercury in drinking water in the town of Caimanes and presence of very high concentrations of manganese, mercury, iron, nickel and molybdenum in the Pupio river is reported. Evidence suggests that these increased concentrations of toxic elements result from the El Mauro mining tail filtrations in the IV Region of Chile. The delayed effects of chronic and prenatal exposure to these toxic agents are described.

Determination of Pb,Cd,Cr and Ni concentration in Imported Indian Rice to Iran

Heavy metal pollution has always been a major cause contamination of environment and considered as a major concern for food health. Rice is the most popular food among Iranians and presence of heavy metals in trace level in rice has received special attention because they are directly related to health. The aim of this research was to investigate the concentration of Pb, Cd, Cr, Ni in rice prevalent in the market of Iran. 20 of the most widely consumed brands of Iranian rice were purchased from local market in Iran. 3 samples of each brand were collected and certain volumes of each sample were digested with acid. Heavy metal contents in the digested samples were determined by atomic absorption spectrometry. The results showed that mean concentration Pb, Cr, Ni in rice samples respectively was 0.387, 0.683, 0.019 [mg/kg]. Notably the Ni and Cr content in the rice samples was found to be below the food sanitary standards in India rice. In the other hand 50% samples content Pb was found to be upper the food sanitary [Pb: 0.3 mg/kg]. The result indicated that weekly intake of heavy metal by rice was below the provisional tolerable weekly intake recommended by WHO/FAO. However, risk assessments needs considerable attention and better prevention this low pollution

Determinaçâo de metais classificados como de importância toxicológica no molusco bivalve Anadara notabilis (Róding, 1798) encontrado em Galinhos, Rio Grande do Norte, Brasil / Determination of metals of toxicological importance in the bivalve Anadara notabilis (Rõding, 1798) of Galinhos, coast of Rio Grande do Norte, Brazil

Os moluscos bivalves são consumidos por todo o mundo, constituindo-se em um recurso natural de boa aceitação pela população. Foi escolhido o molusco Anadara notabilis (conhecido como Xibiu ou Búzio) para este trabalho pelo seu tamanho característico, bem maior que os mariscos mais comuns, e também por não ter sido encontrado na literatura nenhuma informação toxicológica sobre esta classe de moluscos. Todos os íons metálicos foram determinados por espectroscopia de emissão ótica com plasma indutivamente acoplado (ICP-OES) descrito pela metodologia U.S. EPA 6010C. Os resultados mostraram que estiveram presentes no molusco vários metais de caráter tóxico, porém apenas o cromo obteve valor acima do permitido pela legislação brasileira.Dentre os metais classificados como tóxicos o cobre que apresentou valor de 5,7 mg/Kg, o níquel que apresentou teor de 4,23 mg/Kg e o cromo, o único acima dos valores permitidos pela legislação brasileira, com teor de 1,7 mg/Kg, sempre considerando a amostra in natura. Como os moluscos têm a propriedade de acumular metais em seu organismo, para o consumo desse tipode alimento, deve-se tomar cuidado com as áreas próximas de sua coleta ou se cultivado, é necessário prevenir fatores que influenciem em sua contaminação.

Bivalve molluscs are consumed throughout the world, constituting a natural resource with good acceptance by the population. The mollusc Anadara notabilis (know as eared ark) was chosen for this study due to its characteristic size, much larger than most common shellfish, and the lack of toxicological information found in literature for this class of mollusks when considering metal ions toxicity. Metal ions were measured by inductively coupled plasma optical emission spectroscopy (ICP-OES), method described by U.S. EPA 6010C. Results showed that several toxic metals were present in shellfish, however only chrome was measured in levels higher than those allowed by Brazilian legislation. Among those classified as toxic metals, copper showed a value of 5.7 mg / kg, nickel of 4.23 mg / kg andchromium of 1.7 mg / kg, when considering whole shellfish samples. As molluscs are able to accumulate metals in their body, for its consumption care should be taken regarding the areas in close proximity to their collection or cultivation, including prevention of factors that influence contamination.

Use of Pyracantha coccinea Roem. as a possible biomonitor for the selected heavy metals

In this study, copper, iron, manganese and nickel levels of branches and leaves of Pyracantha coccinea Roem. [firethorn] were measured for determining the heavy metal pollution in Mugla Province. Plant samples were collected from 34 different localities in four different areas of Mugla Province, during 2006 vegetation period. Unwashed and washed leaf samples and unwashed branch samples were subjected to analysis and copper, iron, manganese and nickel concentrations of samples were measured by inductively coupled plasma optical emission spectrometry. The obtained data were analyzed with "statistical package for the social sciences" statistics program. As a result of measurements, the highest average and lowest values and their collected stations were as follows; the highest average [5.89 +/- 0.04 micro g/g dw] and the lowest [5.20 +/- 0.03 micro g/g dw] values of copper were measured near highways. The average highest iron value [9.53 +/- 1.68 micro g/g dw] was in industrial area while the lowest was near highways [1.73 +/- 0.54 micro g/g dw]. The highest value of magnesium accumulation [1.00 +/- 0.16 micro g/gdw] was measured near highways. The lowest value was determined in urban area [0.40 +/- 0.14 micro g/g dw]. The average highest level of nickel was in industrial area while the lowest was determined in urban area. The values were 14.34 +/- 1.59 micro g/g and 4.05 +/- 0.51 micro g/g dw. As a result, it was proven that P. coccinea could be used as a biomonitor species for some of these heavy metals especially for copper and nickel

Impact of sewage irrigation on speciation of nickel in soils and its accumulation in crops of industrial towns of Punjab.

Analysis of soil samples collected from sewage and tube well irrigated soils of Ludhiana, Amritsar Jalandhar and Mandi Gobindgarh, revealed that Diethylene triamine pentaacetic acid extractable nickel ( DTPA-Ni) was found to be higher in sewage fed soils. Sewage irrigation increased soil DTPA-Ni content by 3.04 times over the tube well irrigated soils. The content of DTPA-Ni showed decreasing trend with depth. Hydrogen concentration (pH) was negatively and significantly correlated with DTPA-Ni nickel whereas, organic carbon and total Ni show positive and significant correlation. Sequential fractionation was carried out to partition Ni in to fractions namely exchangeable and water soluble, organic bound, carbonate bound, Mn oxides bound, amorphous Fe oxides, crystalline Fe oxides bound and residual. Plant availability of these fractions is believed to decrease in the above order. Sequential fractionation indicated that every extracted fraction exhibited increase in Ni content with sewage irrigation with most prominent increases occurring in the organic and oxide fractions. The lowest amount of Ni in exchangeable and water soluble and the highest in residual pools testify that plants grown on these soils may not suffer from Ni toxicity. Though all the crops irrigated with sewage water had appreciably higher concentration of Ni as compared to the crops raised with tube-well water yet raya (Brassica juncea) and toria (Brassica campestris) accumulated higher content of heavy metals as compared to other crops, with higher content in roots than shoots. Transport index suggested that major part of taken up Ni is translocated to top parts of plant. Based on values of transport indices, different crops maybe arranged as toria > raya = maize > bajra > lady finger. As the plants take up nickel readily and there is danger of its excessive accumulation in plant organs and devaluation of the plant products. This is topical issue particularly in crops used for direct consumption.

Voltammetric determination of trace metals Zn2+, Cd2+, Pb2+, Cu2+, Co+2 and Ni+2 in some medicinally important plants from Western Ghats, Karnataka State, India.

Trace metal levels in selected medicinal plant leaves from Western Ghats, Karnataka, India were studied A method for the determination of Zinc, Copper, Lead and Cadmium simultaneously in the pH of 4.5 in citrate buffer, and Cobalt and Nickel simultaneously in the pH 9.2 in ammonia buffer medium has been optimized. Electrochemical method, Differential Pulse Anodic Stripping Voltammetry (DPASV) has been used for quantification. The optimized procedure has been successfully applied for the determination of the above-mentioned metal ions in some medicinally important plant leaves from Western Ghats, Karnataka, India. The concentrations of trace metals in the medicinal plant samples were found to be in the ranges: 15.61-20.71 mg g(-1) for copper, 0.056-0.10 mg g(-1) for cadmium, 0.91-1.81 mg g(-1) for lead, 0.42-0.96 mg g(-1) for nickel, 1.21-1.97 mg g(-1) for cobalt and 23.29-32.52 mg g(-1) for zinc. The effect of pH, deposition time and potential has been studied and optimized. The study reveals that all the trace metals are well within the maximum permissible limits, therefore, medicinal plants of this region are very much suitable for medicinal use. The results are compared with the data obtained by atomic absorption spectroscopy.

Evaluating the Nickel Content in Metal Alloys and the Threshold for Nickel-Induced Allergic Contact Dermatitis

Many patients are currently suffering from nickel (Ni)-induced allergic contact dermatitis (ACD). There have been few Korean studies dealing with the threshold of Ni-induced ACD and quantifying the total amount of Ni in the metal alloys. The aim of this study is to evaluate the amount of Ni leached from metal alloys and Ni contents in metal alloys, and to estimate the threshold of Ni-induced ACD. All the earrings we examined leached below 0.5 microgram/cm(2)/week, the upper limit of European Union (EU) regulation, but the other metal alloys leached a much higher amount of Ni than the limit. Likewise, all the earrings we examined contained less than 0.05% Ni (500 microgram/g), the upper limit of EU regulation, but the other metal alloys exceeded this limit. Twenty Ni-sensitive subjects, who were patch-tested with various concentrations of Ni sulphate, showed positive reactions to 5% and 1% Ni sulphate, 10 subjects showed positive reactions to 0.01%, and the most sensitive subject showed reaction even to 0.0001%. The subjects in this study were more sensitive to Ni than those in the previous studies done in Europe. Taken together, strictly regulating the Ni-containing alloys that are made in Korea is needed to lower the occurrence of Ni-induced ACD.

Comparative study of selected organically and conventionally vegetables

Due to the growing interest in organic products, a comparison between the chemical and biological safety of organic and conventional vegetables was undertaken. Organic and conventional potato, tomato and cucumber were the products purchased from Sekem Company, Cairo, Egypt. Moisture, protein, fat, ash, carbohydrates, phosphorus, vitamin C, heavy metals such [Nickel, cadmium.cobalt and lead], and pesticides residues were determined in all investigated samples. The biological experiment was done on 42 adult male albino rats. Rats were divided into 7 groups. Group [1] fed on basal diet [control group], group [2] fed on basal diet with organic tomato [2.5%], group [3] fed on basal diet with conventional tomato [2.5%], group [4] fed on basal diet with organic cucumber [2.5%], group [5] fed on basal diet with conventional cucumber [2.5%], group [6] fed on basal diet with organic potato [5%], group [7] fed on basal diet with conventional potato [5%]. At the end of the experimental period [4 weeks] rats were scarified and blood samples were collected to separate serum for estimating liver and kidney functions and lipid profile. The results illustrated that, the nutritional value of organic vegetables was higher than the conventional vegetables. The level of pesticides residues in organic vegetables was very low comparing to conventional vegetables. In addition, the heavy metals [cadmium, nickel, and lead] were found in both organic and conventional vegetables but they were higher in conventional vegetables than organic vegetables. The organic tomato significantly increased serum HDL-C. Organic cucumber significantly decreased serum VLDL-C and TG. While all organic and conventional did not affect serum LDL-C. Total cholesterol and kidney functions. Conventional cucumber caused a significant increase in serum uric acid. On the other hand, all tested conventional vegetables significantly increased serum ALT. While organic tomato and cucumber did not affect liver enzymes but, organic potato led to slightly increase in liver enzymes. In conclusion, the present study suggests that regular survey of organic vegetables should be done in order to assure food safety and to protect the end users from food risks that might injure their health

Estimation of trace elements in sound and carious enamel of primary and permanent teeth by atomic absorption spectrophotometry: an in vitro study.

The influence of trace elements on the prevalence of caries is a complex subject. However, the demonstration of an inverse relationship between caries prevalence and fluoride (F) intake indicates the potential effect of trace elements on caries. AIMS AND OBJECTIVES: This in vitro study sought to estimate and compare the trace element concentrations in sound and carious enamel of primary and permanent teeth. MATERIALS AND METHODS: Forty sound and carious primary and permanent teeth, extracted from children and adolescents of Davangere city, were collected. The teeth were divided into four groups (of ten each) and enamel samples were prepared by mechanical grinding. The trace elements were estimated using atomic absorption spectrophotometer. RESULTS AND CONCLUSIONS: The results of our study showed the presence of 18 trace elements (F, Sr, K, Al, Si, Ni, B, Fe, Cu, Mn, Co, Cr, Zn, Mg, Se, Pb, Mo, and V) in the enamel of sound and carious primary and permanent teeth. The mean, standard deviation, and range (at 95% confidence level) were calculated for each element. The concentrations of F, Sr, and K were significantly ( P <0.05) higher in sound enamel of permanent teeth than in sound enamel of primary teeth. The concentrations of F, Sr, K, Al, and Fe were significantly ( P <0.05) higher in sound enamel of permanent teeth than in carious enamel of permanent teeth. The concentrations of F, K, and Si were significantly ( P <0.05) higher in sound enamel of primary teeth than in carious enamel of primary teeth.