Ultra trace determination of bromate in mineral water and table salt by liquid chromatography-tandem mass spectrometry

Electrochemical Sensors for Determination of Bromate in Water and Food Samples-Review

The application of potassium bromate in the baking industry is used in most parts of the world to avert the human health compromise that characterizes bromates carcinogenic effect. Herein, various methods of its analysis, especially the electrochemical methods of bromate detection, were extensively discussed. Amperometry (AP), cyclic voltammetry (CV), square wave voltammetry (SWV), electrochemiluminescence (ECL), differential pulse voltammetry and electrochemical impedance spectroscopy (EIS) are the techniques that have been deployed for bromate detection in the last two decades, with 50%, 23%, 7.7%, 7.7%, 7.7% and 3.9% application, respectively. Despite the unique electrocatalytic activity of metal phthalocyanine (MP) and carbon quantum dots (CQDs), only few sensors based on MP and CQDs are available compared to the conducting polymers, carbon nanotubes (CNTs), metal (oxide) and graphene-based sensors. This review emboldens the underutilization of CQDs and metal phthalocyanines as sensing materials and briefly discusses the future perspective on MP and CQDs application in bromate detection via EIS.

Elevated concentrations of bromate in Drinking water and groundwater from Kuwait and associated exposure and health risks

Drinking water is an important source of human exposure to bromate, an ubiquitous environmental contaminant and a suspect human carcinogen. Nevertheless, little is known with regard to bromate exposure from water produced by thermal desalination of seawater. The purpose of this study was to determine the occurrence of bromate in desalinated drinking water and groundwater from Kuwait and estimate associated exposure and health risks to consumers. In this study, 194 tap and ground water samples collected from Kuwait were analyzed for the presence of bromate and bromide (reduced form of bromine). Bromate was found in almost all tap water samples with a mean concentration of 19.6 μg/L, which is higher than the maximum acceptable contaminant level (MCL) of 10 μg/L. The mean concentration of bromide in tap water samples was 46.2 μg/L. In bottled water, lower mean bromate concentration was found (2.89 μg/L) with mean bromide levels at 76.1 μg/L. Saline brackish water had bromate concentration at 9.48 μg/L while bromate was not detected in saline groundwater/well water samples. The mean estimated daily intake (EDI) of bromate by the Kuwaiti population through tap water and commonly consumed bottled water was 21.7 μg/d and 3.21 μg/d, respectively. Among the five age groups, 3 to 5-year-old children had the highest EDI of bromate at 15.4 μg/d. The excess cancer risk due to ingestion of bromate in tap water was estimated to be 3.92 × 10^-4, which is approximately one order of magnitude higher than the maximum acceptable level of risk (2× 10^-5). This study highlights the significance of desalinated water as a source of bromate exposure.

Carbon dot doped silica nanoparticles as fluorescent probe for determination of bromate in drinking water samples

A simple and effective strategy for designing a fluorescent probe for bromate was described in this work. Organosilane modified carbon dots were prepared by pyrolysis of citric acid in N-(β-aminoethyl)-γ-aminopropyl methyldimethoxysilane solvent at 230 °C and further doped onto silica nanoparticles by a silylation reaction. The fluorescence of carbon dot doped silica nanoparticles was quenched by bromate in acidic medium. By utilizing this property, the nanoparticle could be used as a sensor to detect bromate. The parameters affecting the performance of the sensor probe such as types of acid medium, acid concentration, reaction temperature, and time were investigated and optimized. The detection limit of the sensor was found to be 1.1 ng mL−1, with a linear range from 8 to 400 ng mL−1 and relative standard deviation of 2.0% (150 ng mL−1, n = 9). The method was successfully applied to the determination of bromate in drinking water samples, and the recoveries were in the range of 96.3%–103.7%.

Extractive liquid-liquid spectrofluorometric determination of trace and ultra concentrations of bromate in water samples by the fluorescence quenching of tetraphenylphosphonium iodide

A low cost and selective spectrofluorimetric method has been developed for trace determination of bromate ions in water. The method has been based upon complete extraction of the produced yellow colored ion associate of the reagent tetraphenylphosphonium iodide (TPP(+) I(-)) and bromate ions from aqueous media into chloroform and measuring the fluorescence quenching at λex/em=242/305nm. The composition, stability and the most probable mechanism of the produced associate have been determined. The plot of fluorescence intensity of TPP(+) I(-)vs. bromate concentration was linear in the range 0.86-150.0μgL(-1). The limits of detection (LOD) and quantification (LOQ) of BrO3(-) were 0.24 and 0.76μgL(-1), respectively. The method was found free from most of the interferences present in chromatographic, spectrofluorometric and spectrophotometric methods. Intra and inter-day laboratory accuracy and precision for analysis of bromate in water were determined. The method provides better performance compared to the international standard method recently issued (ISO 11206:2011). The method was applied satisfactorily for analysis of 1.0μgL(-1) bromate in the presence of high excess of chloride (50mg/L) without pretreatment with a relative standard deviation (RSD) of ±2.9%. The method was applied for analysis of bromate in various water samples. Statistical comparison of the results of the proposed method with those obtained by the standard method revealed no significant differences in the accuracy and precision.

A new catalytic oxidation method for sensitive quantification of bromate in flours and bottled water using AgNPs

In this paper, a simple and sensitive spectrophotometric method for the determination of nanomolar level of bromate, based on the catalytic effect of silver nanoparticles on the oxidation of acid red 14 by potassium bromate, is described. The reaction rate was monitored spectrophotometrically by measuring the decrease in absorbance of acid red 14 at 516 nm. The detection limit of the method was 8 ng/mL, and the linear range was between 15 and 130 ng/mL. The effects of acidity, concentration of reactants and reaction time, and external ions were also discussed. The optimum reaction conditions were fixed, and some kinetic parameters determined. The relative standard deviation for the determination of bromate at the concentration of 50 ng/mL was calculated to be 0.996 % (n = 10). The method has been successfully applied to the determination of bromate in flours and bottled waters.