Radon and tritium measurements in drinking water in a region of central Italy (Umbria)

Summary In the last years the interest in drinking and mineral water radioactivity has grown. Recently national and EU regulations replaced the previous drinking water norms with the aim to strengthen consumers security concerning drinking water quality. Perugia and Urbino Universities carried out a joint study on the radiological characterization of the water destined for human consumption in the Umbria region. The aim of this work was to produce a map of the radon and tritium concentrations in the water of this area as a basis for the implementation of hydrogeological knowledge and to determine a possible related radiological risk for the local population.²²²Rn measurements were performed by liquid scintillation and gamma-spectrometry and³H measurements by liquid scintillation. Up to now, the²²²Rn concentrations ranged 5.9-65.79 Bq/l and³H concentrations are always lower than the detection limit (8.6 Bq/l).     

Determination of <Superscript>3</Superscript>H, <Superscript>226</Superscript>Ra, <Superscript>222</Superscript>Rn and <Superscript>238</Superscript>U in Austrian ground- and drinking water

Screening measurements for ³H, ²²⁶Ra, ²²²Rn and ²³⁸U in ground water were performed within a ground- and drinking water project in Austria. The aim of this project is to get an overview of the distribution of natural radionuclide activity concentration levels in ground water bodies. In some cases this water is used for drinking water abstraction. In this paper methods and results of the screening measurements are presented. Regions with high activity concentrations were identified and in these regions further investigation for ²²⁸Ra, ²¹⁰Pb and ²¹⁰Po will be conducted.     

Solid-phase extraction and high-performance liquid chromatography mass spectrometry analysis of nitrosamines in treated drinking water and wastewater

N-Nitrosamines, including N-nitrosodimethylamine (NDMA), were identified as chlorination byproducts in drinking water in 1989. Nitrosamines are known rodent carcinogens and probable human carcinogens, and so they are considered disinfection byproducts (DBPs) of public health concern. Epidemiological studies show a potential association of consumption of chlorinated drinking water with an increased risk of bladder cancer. As small, relatively polar DBPs that often occur at low-ng/L concentrations in water, nitrosamines pose analytical challenges for accurate determination. Sample preparation (e.g., the commonly used solid-phase extraction) plays a critical role in achieving reliable determination of nitrosamines at ng/L concentrations. Historically, gas chromatography (GC)-based techniques have been used for nitrosamine analysis. Recently, newly developed liquid chromatography–tandem mass spectrometry (LC-MS²) methods have shown potential advantages in determining polar DBPs. This review focuses on the sample preconcentration methods and LC-MS² determination of nitrosamines in drinking water and wastewater. It also provides a historical perspective on nitrosamines and their occurrence in drinking water.     

Quality and Human Health Risk Assessment of Metals and Nitrogen Compounds in Drinking Water from an Urban Area Near a Former Non-Ferrous Ore Smelter

The quality and potential health risk of drinking waters in Medias, a town near a former non-ferrous ore smelter in Romania, was assessed using the drinking water quality index (DWQI), hazard quotient (HQ) and total hazard quotient (THQ). A total of 29 water samples collected from 26 wells and 3 springs used as drinking water sources, located in near proximity to agricultural, industrial or household contamination sources, were characterized. The obtained results indicated high NO₂^?, NO₃^?, Cd and Mn levels that exceeded the corresponding maximum allowable concentrations. According to the DWQI values, only 10% of water sources have acceptable quality, while 21% are threatened, and 69% have poor- quality. The health risk assessment suggested a high risk for NO₃^? for more than 72% of the drinking waters HQ_NO3^??>?1.0 but no risk for metals and NO₂^? (HQ_metals< 1.0; HQ_NO2^?< 1.0).     

Activity concentration of 40K in drinking water in Slovenia

Activity concentrations of ⁴⁰K and ³H in drinking water from four sources in the vicinity of NPP Kr?ko and their correlation with geological data are presented. The data extends from the year 1996 until present. In addition, activity concentrations of ⁴⁰K in drinking water at randomly selected sources in Slovenia are presented on a map. These activity concentrations vary by more than an order of magnitude with the largest values in northeastern part of the country.     

Radon (222Rn) in underground drinking water supplies of the Southern Greater Poland Region

Activity concentration of the ²²²Rn radionuclide was determined in drinking water samples from the Sothern Greater Poland region by liquid scintillation technique. The measured values ranged from 0.42 to 10.52 Bq/dm³ with the geometric mean value of 1.92 Bq/dm³. The calculated average annual effective doses from ingestion with water and inhalation of this radionuclide escaping from water were 1.15 and 11.8 μSv, respectively. Therefore, it should be underlined that, generally, it’s not the ingestion of natural radionuclides with water but inhalation of the radon escaping from water which is a substantial part of the radiological hazard due to the presence of the natural radionuclides from the uranium and thorium series in the drinking water.     

Determination of strontium-90 in various kinds of water after Chernobyl accident in Austria

As a consequence of the reactor-accident of Chernobyl on Tuesday 29 April 1986 the environmental radioactivity in Austria increased for above the level recorded before. Depending on the amount of precipitation the deposition of radioactive fallout showed great differences. Many water samples /rain water, lake water, swimming pool water, drinking water, underground water/ collected /during period of April 29 to May 30/ from Vienna, Lower Austria and Steiermark were analyzed for⁹⁰Sr. The following concentrations in /nCi 1^–1/ of⁹⁰Sr was found: 8.69±2.3 for rain water, 0.09±0.12 for lake water, 0.08–0.18 for swimming pool, 0.04–0.13 for drinking water, 0.07–0.2 for underground water. The⁹⁰Sr concentration was not higher than the maximal permissible /0.004–0.4 nCi 1^–1/ except for rain water.     

Radon concentration in drinking water sources of the Main Campus of the University of Peshawar and surrounding areas, Khyber Pakhtunkhwa, Pakistan

Radon and its progenies in indoor environment have been identified as the main sources of radiation dose to the people from natural radioactive sources. Presence of radon in drinking water causes radiation related health hazards both through inhalation and ingestion. In this study 36 drinking water samples from taps, boreholes and deep tube wells within the Main Campus of the University of Peshawar and adjoining area were analyzed with RAD7 electronic device for radon content determination. These water samples have a mean, maximum and minimum radon value of 8.8 ± 0.8, 18.2 ± 1.0, and 1.6 ± 0.3 Bq L⁻¹, respectively. Eleven drinking water samples analyzed have radon levels in excess of the EPA recommended maximum contaminant level (MCL) of 11.1 Bq L⁻¹. These include 89% from tube wells, 8% from tap water, and 50% from shallow boreholes. Radon levels of about 31% of the total samples used by the inhabitants of the study area are higher than the EPA advised level of 11.1 Bq L⁻¹. The annual effective dose from radon in water due to its ingestion and inhalation per individual has also been estimated. The mean radon concentration and mean annual effective dose due to radon in water of this study have been compared with the mean radon concentration and mean annual effective dose of earlier investigators due to radon in water from different localities of India and Pakistan. The mean annual effective doses of all the samples are lower than the reference level of 0.1 mSv a⁻¹ for drinking water of WHO and EU Council. It has been concluded that drinking water of the study area is generally safe as far as radon related health hazards are concerned with the exception of a few isolated cases. It has been found that radon levels within the region have a positive correlation with depth of the water sources.     

Radionuclides of 210Po, 234U and 238U in drinking bottled mineral water in Poland

A study of the radioactive content of drinking mineral bottled water in Poland was carried out. ²¹⁰Po,²³⁸U and ²³⁴U activity concentrations were determined by alpha-spectrometry with low-level-activity silicon detectors. The results revealed that the mean concentration of ²¹⁰Po,²³⁸U and ²³⁴U in analyzed water sample were 1.28, 0.80 and 0.80 mBq^.dm^-3, respectively. The effective doses due to the polonium and uranium emissions were calculated for bottled drinking water.     

The Sorben-Tec system for rapid dosimetric evaluation of <Superscript>137</Superscript>Cs in drinking water

The Sorben-Tec system was developed for rapid evaluation of ¹³⁷Cs in drinking water using a domestic personal dosimeter or beta-radiometer. Linear calibration curves were obtained for dosimetric and beta-radiometric measurement of caesium. In case of 20 L drinking water sample, detection limits of ¹³⁷Cs were found to be 12.3 and 2.0 Bq L^?1 for dosimetric and beta-radiometric measurement respectively. This system is recommended for using by non-professionals who are living at radioactively contaminated areas or near nuclear power plants.     

Effective removal of uranium ions from drinking water using CuO/X zeolite based nanocomposites: effects of nano concentration and cation exchange

For the first time, effects of CuO nanoparticles concentration (from 1 to 24.2 wt%) in CuO/NaX nanocomposite and replacing various cations (Ag⁺, K⁺, Ca²⁺, and Mg²⁺) with Na⁺ ions in NaX zeolite on removal of uranium ions from drinking water are reported. The removal of uranium was performed under natural conditions of pH, laboratory temperature and the presence of competing cations and anions that are available in tap water of Isfahan city. Characterization of parent NaX zeolite and modified samples were investigated using X-ray fluorescence, X-ray powder diffraction patterns, scanning electron microscopy, and atomic absorption spectroscopy methods. Using Langmuir, Freundlich, and C-models, isotherms of equilibrium adsorption were studied. Results show the removal efficiency and distribution coefficient of NaX zeolite decrease in the presence of other competing anions and cations that exist in drinking water. But, modification of NaX zeolite with various cations and CuO nanoparticles might enhance the ability of X zeolite in removing uranium from drinking water.     

Determination of 3-amino-1,2,4-triazole (amitrole) in environmental waters by capillary electrophoresis

3-Amino-1,2,4-triazole (amitrole) is a widely used pesticide, with many difficulties to be analyzed at the regulatory level in drinking water, because its high solubility in water. This paper describes a simple and fast method for the simultaneous determination of amitrole and atrazin-2-hydroxy, principal degradation product of s-triazines, by capillary zone electrophoresis. Separation and determination of these herbicides in water samples was performed in 0.02 mol l⁻¹ phosphate buffer at pH 3.2. The method allows determination of the amitrole and atrazin-2-hydroxy in water samples in concentration lower than 100 μg l⁻¹. The detection limits using a previous preconcentration step of amitrole in Alberche River (Comunidad Autónoma de Madrid, Spain) and drinking water spiked samples was of 4 μg l⁻¹.     

Sensitive determination of hydrazine in water by gas chromatography–mass spectrometry after derivatization with ortho-phthalaldehyde

A gas chromatography–mass spectrometric (GC–MS) method has been established for the determination of hydrazine in drinking water and surface water. This method is based on the derivatization of hydrazine with ortho-phthalaldehyde (OPA) in water. The following optimum reaction conditions were established: reagent dosage, 40 mg mL⁻¹ of OPA; pH 2; reaction for 20 min at 70 °C. The organic derivative was extracted with methylene chloride and then measured by GC–MS. Under the established condition, the detection and the quantification limits were 0.002 μg L⁻¹ and 0.007 μg L⁻¹ by using 5.0-mL of surface water or drinking water, respectively. The calibration curve showed good linearity with r² = 0.9991 (for working range of 0.05–100 μg L⁻¹) and the accuracy was in a range of 95–106%, and the precision of the assay was less than 13% in water. Hydrazine was detected in a concentration range of 0.05–0.14 μg L⁻¹ in 2 samples of 10 raw drinking water samples and in a concentration range of 0.09–0.55 μg L⁻¹ in 4 samples of 10 treated drinking water samples.     

Visual detection of Al ions using conjugated copolymer-ATP supramolecular complex

A colorimetric Al³⁺ sensor based on fluorescence recovery of a conjugated copolymer-ATP complex is proposed. An optimized ratio of two polythiophene (PT) monomers is utilized to synthesize copolymer (CP) that yielded maximized colorimetric response for Al³⁺ in deionized (DI) and tap water. The electrostatic disassembly of CP-ATP upon addition of Al³⁺ led to an evident visual color change. The lowest concentration of Al³⁺ for naked eye observation is around 4 μM, which is below the threshold levels in drinking water according to European Economic Community (EEC) standard. Besides, the proposed assay showed a similar response to Al³⁺ in tap water. The proposed methodology showed selective and sensitive detection for Al³⁺ in analytically relevant concentration ranges without involving sophisticated instrumentation, illustrating the applicability for on-site drinking water monitoring.     

Neutron induced radiography in the determination of boron in drinking water

Neutron induced radiography has been applied to the determination of boron concentrations in drinking water, collected from natural springs of Reshian and Muzaffarabad areas of Azad Kashmir, Pakistan, using CR-39 etched track detectors. The technique is based upon the simultaneous irradiation with thermal neutrons of a sample of unknown concentration and a standard of known boron concentration, fixed on a track detector. The subsequent counting of alpha and ⁷Li tracks in the detector resulting from the ¹⁰B(n,)⁷Li nuclear reaction is done after chemical etching. Boron concentration in the sample is determined by comparing ⁷Li and alpha-particle track density with that of a standard of known boron concentration. Boron concentrations in drinking water samples from Muzaffarabad and Reshian area of Azad Kashmir have been found to vary from (0.054±0.001) mg/l to (0.250±0.004) mg/l with an average of (0.16±0.002) mg/l. The observed concentration of boron in drinking water has been found to be less than the provisional Maximum Acceptable Concentration level (0.4 mg//l) of WHO. The drinking water from the reported area has been found to be within safe limits as far as boron related health hazards are concerned.This revised version was published online in November 2005 with corrections to the Cover Date.     

Pressure-assisted electrokinetic injection for on-line enrichment in capillary electrophoresis-mass spectrometry: a sensitive method for measurement of ten haloacetic acids in drinking water

Haloacetic acids (HAAs) are by-products of the chlorination of drinking water containing natural organic matter and bromide. A simple and sensitive method has been developed for determination of ten HAAs in drinking water. The pressure-assisted electrokinetic injection (PAEKI), an on-line enrichment technique, was employed to introduce the sample into a capillary electrophoresis (CE)–electrospray ionization–tandem mass spectrometry system (ESI-MS/MS). HAAs were monitored in selected reaction monitoring mode. With 3 min of PAEKI time, the ten major HAAs (HAA10) in drinking water were enriched up to 20,000-fold into the capillary without compromising resolution. A simple solid phase clean-up method has been developed to eliminate the influence of ionic matrices from drinking water on PAEKI. Under conditions optimized for mass spectrometry, PAEKI and capillary electrophoresis, detection limits defined as three times ratio of signal to noise have been achieved in a range of 0.013–0.12 μg L⁻¹ for ten HAAs in water sample. The overall recoveries for all ten HAAs in drinking water samples were between 76 and 125%. Six HAAs including monochloro- (MCAA), dichloro- (DCAA), trichloro- (TCAA), monobromo- (MBAA), bromochloro- (BCAA), and bromodichloroacetic acids (BDCAA) were found in tap water samples collected.     

Determination of nitrites and nitrates in drinking water using capillary electrophoresis

This work was concerned with developing an electrophoretic method for rapid determination of nitrites and nitrates in drinking water. The background electrolyte was Tris-HCl buffer with an addition of cetyltrimethylammonium chloride to reverse the electro-osmotic flow. Online preconcentration of samples using the field-amplified sample stacking method provided detection limits of 0.003 mg L^?1 (i.e. 65 nM) for nitrites and 0.010 mg L^?1 (i.e. 160 nM) for nitrates, which are sufficiently low for quality control of drinking water. The method was tested in a concentration range corresponding to real drinking water samples and the differentiation between nitrites and nitrates was sufficient for simultaneous determination of nitrites at their concentrations of the order of tenths of mg L^?1 and nitrates at their concentrations of the order of units to tens of mg L^?1. A number of authors have neglected this important aspect when concentrating only on achieving the lowest possible detection limits. Separation of the two analytes and iodate as an internal standard was achieved in only three minutes. Total analysis time including preconditioning was eight minutes.     

A novel polymeric membrane electrode for the potentiometric analysis of Cu in drinking water

Based on a novel ionophore, an ion-selective electrode has been developed for the determination of Cu²⁺ in drinking water. Its selectivity behavior is characterized and its lower detection limit optimized for measurements with different electrolyte backgrounds. The lower detection limit was 2 × 10⁻⁹ M Cu²⁺ for samples with low ionic background and 1 × 10⁻⁷ M Cu²⁺ with ionic background typically found in drinking water.     

The defluoridation of drinking water using multi-walled carbon nanotubes

In this study, the potential sorption capacity of multi-walled carbon nanotubes (MWCNTs) was investigated as a means of removing fluoride from the drinking water of a number of regions in Iran and from experimental solutions. The test was conducted in both batch and continuous operation modes. Batch mode experiments were used to study the effect of parameters such as pH, contact time, ionic strength, adsorbent dose, adsorbent capacity, and the presence of foreign anions on the efficiency of fluoride removal. The results showed that the highest level of sorption occurs at pH 5 (about 94% at 18 min). The ionic strength of the solutions and the presence of co-anions such as chloride, nitrate, sulfate, hydrogen carbonate, perchlorate had a negligible effect on the sorption of F⁻ onto MWCNTs. Sorption capacity measurements revealed that MWCNTs have a saturation capacity of 3.5 mg of F⁻ per gram. Sorption data were best fitted with the Fruendlich sorption isotherm equation, which indicates that F⁻ tends to be adsorbed on MWCNTs in a multilayered manner. Experiments using Kohbanan city drinking water, which contains the highest level of F⁻ among the drinking water samples studied, showed that MWCNTs can remove over 85% of fluoride content.     

Use of the Sorben-Tec system for rapid dosimetric evaluation of <Superscript>222</Superscript>Rn level in drinking water

The Sorben-Tec system was tested for rapid dosimetric evaluation of ²²²Rn level in drinking water in domestic conditions using a dosimeter of beta radiometer as a measurement equipment. It was shown that the method is cheap, rapid and very simple, therefore it can be used by population for rapid radiation safety assessment of drinking water. The sorption-active Sorben-Tec system contains iron hexacyanoferrate allowing for separation of approximately 40% of both ²¹⁴Pb and ²¹⁴Bi, the short-lived decay products of ²²²Rn from 5 L water sample. It was assessed that the Sorben-Tec system provides detection limits of radon in 5 L water samples of 35–40 and 10 Bq L^?1 for dosimetric and radiometric measurements respectively. The total time consumption of analysis does not exceed 1 h excluding the time for ²¹⁴Pb and ²¹⁴Bi ingrowth in the water sample (min. 3 h). Due to an insignificant sorption of radon, it is possible to reuse spent Sorben-Tec system again 3–4 h after previous analysis.