Candidate reference measurement procedures for chloride, potassium, sodium, calcium, magnesium, and lithium by inductively coupled plasma (isotope dilution) sector field mass spectrometry (ICP-(ID) SFMS) in serum.

BACKGROUND: Standardization of the measurement of electrolyte concentrations in serum is of considerable interest for quality assurance in patient care. To promote the ongoing process of standardization we developed candidate reference measurement procedures of highest metrological order for Cl, K, Na, Ca, Mg, and Li using ICP-(ID) SFMS. METHODS: Serum samples were diluted with 4 mmol/L nitric acid and were spiked with the internal standard for quantification, separately for each analyte. The samples were introduced in the ICP-SFMS device by continuous infusion using a peristaltic pump. The measurement results were compared with reference measurement procedure values obtained by atom absorption spectroscopy, flame emission spectroscopy, and coulometry. The measurement accuracy and precision was calculated by analyzing certified reference materials and EQAS samples. RESULTS: The mean coefficient of variation (CV) of the ICP-MS procedures for the serum samples was 0.65% for Cl, 0.46% for K, 0.51% for Na, 0.77% for Ca, 0.78% for Mg, and 0.58% for Li. The mean bias from target values of NIST certified reference materials was +0.85% for Cl, -0.46% for K, +0.68% for Na, -0.21% for Ca, +0.27% for Mg, and -0.39% for Li. CONCLUSIONS: Candidate reference measurement procedures for 6 electrolytes were developed by high performance magnetic sector field ICP-MS fulfilling the requirements of ISO 15193:2009 for reference measurement procedures with traceability to SI according to ISO 17511:2003 and can be used for setting target values in EQAS and for certification of reference materials.

Chronic toxicity of chloride to freshwater species: effects of hardness and implications for water quality guidelines.

Toxicity tests using nine freshwater species (Ceriodaphnia dubia, Daphnia magna, Oncorhynchus mykiss, Pimephales promelas, Lumbriculus variegatus, Tubifex tubifex, Chironomus dilutus, Hyallela azteca, and Brachionus calyciflorus) were conducted to evaluate their sensitivity to chloride. Acute-to-chronic ratios (ACRs) from these tests indicate the ACR of 7.59 employed by the United States Environmental Protection Agency (U.S. EPA) in deriving its water quality guideline for chloride may be conservative; a revised ACR of 3.50 is presented here. The endpoints used to calculate the ACR included 24-h to 96-h median lethal concentrations (LC50s) for acute tests, and 48-h to 54-d inhibition concentration (ICx) values for growth or reproduction for chronic exposures. Data from the present chronic toxicity tests, and other investigators, were used to propose a water quality guideline for long-term exposure to chloride using a species sensitivity distribution (SSD) approach. The 5th percentile from the SSD was calculated as 307 mg/L and proposed as the water quality guideline. Cladocerans were the most sensitive species in the dataset. Ceriodaphnia dubia was used to evaluate the relationship between water hardness and sensitivity to chloride. A strong relationship was observed and was used to establish a hardness-related equation to modify the proposed water quality guideline on the basis of water hardness, resulting in values ranging from 64 mg/L chloride at 10 mg/L hardness to 388 mg/L chloride at 160 mg/L hardness (as CaCO3). These data suggest that current water quality guidelines for chloride may be overly conservative in water with moderate-to-high hardness, and may not be sufficiently protective under soft-water conditions.

Derivation of a toxicity reference value for nitrogen trichloride as a disinfection by-product.

Nitrogen trichloride is a highly volatile chlorination disinfection by-product, very commonly found in the air of indoor swimming pools. The aim of this work is to characterize the hazard associated with it and to determine the concentration at which health effects appear, for application in health risk assessments for users of indoor swimming pools. Hazard identification was based on a literature survey and analysis of animal and human studies, with special attention paid to their methodological quality and to reports of a dose-response relationship. A toxicity reference value was derived for respiratory effects, based on human data from both general and occupational data. We selected a lowest-observed-adverse-effect-level of 0.355mg/m(3) based on objective measurements rather than self-reported effects. Two uncertainty factors were applied to take into account both intra-species variability and the use of a concentration with an effect rather than a no-observed-adverse-effect-level. A toxicity reference value of 4x10(-3)mg/m(3) for nitrogen trichloride is proposed for repeated short exposures. Alternative values based on animal data range from 0.01 to 0.03mg/m(3).

[Standardized sweat chloride analysis for the diagnosis of cystic fibrosis in Korea].

BACKGROUND: Cystic fibrosis is a chronic progressive autosomal recessive disorder caused by the CFTR gene mutations. It is quite common in Caucasians, but very rare in Asians. Sweat chloride test is known to be a screening test for the cystic fibrosis due to the fact that electrolyte levels in sweat are elevated in patients. In this study, sweat chloride levels in Korean population were measured and analyzed by using standardized pilocarpine iontophoresis sweat chloride test. METHODS: The sweat chloride test was performed in 47 patients referred to Yondong Severance Hospital from August, 2001 to April, 2007 and 41 healthy volunteers. The sweat chloride tests were conducted according to the CLSI C34-A2 guideline using pilocarpine iontophoresis method, and the chloride concentrations in sweat were measured by mercurimetric titration. RESULTS: Four patients showed sweat chloride concentrations higher than 60 mmol/L. Reference interval was calculated as 1.4-44.5 mmol/L by analysis of the results of healthy volunteers (n=41). Four patients who exhibited high sweat chloride levels, had characteristic clinical features of cystic fibrosis and their diagnoses were confirmed either by repeated sweat chloride test or genetic analysis. CONCLUSIONS: Standardized sweat chloride test can be utilized as a useful diagnostic tool for cystic fibrosis in Koreans. In cases of sweat chloride levels higher than 40 mmol/L, the test should be repeated for the possible diagnosis of cystic fibrosis. All the confirmed Korean cases of cystic fibrosis showed sweat chloride level above 60 mmol/L.

Potable groundwater quality in some villages of Haryana, India: focus on fluoride.

The fluoride concentration in ground water was determined in ten villages of Rohtak district of Haryana state (India). The fluoride concentration in the underground water of these villages varied from 0.034-2.09 mg/l. Various other water quality parameters, viz., pH, electrical conductivity, total dissolved salts, total hardness, total alkalinity sodium, potassium, calcium, magnesium, carbonate, bicarbonate, chloride and sulfate were also measured. A systematic calculation of correlation coefficients among different physicochemical parameters indicated considerable variations among the analyzed samples with respect to their chemical composition. Majority of the samples do not comply with Indian as well as WHO standards for most of the water quality parameters measured. Overall water quality was found unsatisfactory for drinking purposes. Fluoride content was higher than permissible limit in 50% samples.

Risk assessment of physico-chemical contaminants in groundwater of Pettavaithalai area, Tiruchirappalli, Tamilnadu - India.

A study was carried out in Pettavaithalai area to evaluate the current status of physico-chemical contaminants and their sources in groundwater. Groundwater samples collected from pettavaithalai area in 15 different stations were analyzed every alternative months over a period of two years from August 2000 to June 2002. A sugar mill is situated at the heart of the study area. Three profiles (profile A, B and C) were selected based on the direction in which the sugar mill effluent flows. In each profile five samples were collected from five different station at a regular distance of about 1 Km. The physico-chemical parameters such as pH, EC TDS, TH, NO3, SO4, PO4, Na, K, Ca, Mg, DO, BOD and COD have been analyzed. The results showed that among the three profiles, many of the estimated physico-chemical parameters of profile C were very high when compared to profile B and A which indicates the poor quality of the groundwater around this area.

Monitoring of fluoride concentration in ground water of Prakasham District in India: correlation with physico-chemical parameters.

Fluoride concentrations in surface and ground water samples were determined in eight villages of Prakasham district in India. Thirty-eight samples were collected and analysed for fluoride content along with pH, electrical conductivity, total dissolved solids (TDS), total hardness, total alkalinity, chlorides (C1), sulfates (SO2-) and nitrates (NO ). Fluoride concentrations in surface and ground water samples of these villages varied between 0.5 and 9.0 mg/L. Groundwater samples contained high concentrations of fluorides compared to open well and pond water samples, which could be a major source of fluoride in water since the geological formation of this area consists of fluorite and fluoropatite. From the data, it is evident that the population in the study area is severely affected by fluorosis. Dental and skeletal fluorosis and deformation of bones in children as well as adults were observed in the study area indicating the consequences of excess fluoride concentration. Fluoride concentrations showed good correlation with TDS concentrations (R2 of 0.61) compared to other physico-chemical parameters [EC (R2 - 0.36), nitrate (R - 0.24), total hardness (R - 0.12), chloride (R2 - 0.06) and sulfate (R2 - 4 x 10(-6))].

Ground water contamination in the area adjoining zinc smelter effluent stream.

A preliminary survey of the area adjoining to zinc smelter effluent stream was undertaken to assess ground water contamination. Twenty-five ground water samples from the wells located in the study area were collected and grouped into nine groups based on their lateral and longitudinal position from the stream carrying the effluent discharged from zinc smelter, Debari- Udaipur. The study indicate that waters of wells situated in the vicinity of effluent stream (255m radius) were of medium salinity having higher levels of Ca and Mg and lower values of pH as compared to the waters of the reference wells situated far away from the effluent stream. The Fe, Zn, Cd, Cl, F and SO4 contents ofthe water from the wells located within 80m vicinity of the effluent stream were above the permissible limits for drinking purposes. Furthermore the Zn, Cl and SO4 levels in these waters were so high that they were even not suitable for irrigation, indicating a gradual encroachment of effluent into the native ground water.

Oil production and groundwater quality in the Edwards-Trinity Plateau Aquifer, Texas.

Chloride concentrations and chloride/bromide ratios from 198 water wells in the Edwards-Trinity Plateau Aquifer were compiled, mapped, and evaluated within the context of regional geology and land use. The study area occupies eight counties in west-central Texas, within which oil production and agriculture are predominant land uses. Samples from 49 wells had chloride concentrations above the 250 mg/l secondary drinking water standard, 22 samples had greater than 500 mg/l chloride, and 9 samples exceeded 1000 mg/l chloride. Of the 22 samples above 500 mg/l chloride, 10 had relatively low chloride/bromide ratios of less than 300, consistent with oilfield brine, and 2 had ratios above 2000, consistent with groundwater impacted by evaporite dissolution. The remaining ten samples had chloride/bromide ratios ranging from 300 to 2000, consistent with partial mixing of unimpaired groundwater with evaporite-laden water. There were no significant correlations between chloride concentration and well depth, inconsistent with contaminants originating at the land surface. Results of this study suggest that evaporite dissolution and oilfield brine locally impact the Edwards-Trinity Plateau Aquifer, but the problem is not regionally pervasive.

In vivo airway surface liquid Cl- analysis with solid-state electrodes.

The pathogenesis of cystic fibrosis (CF) airways disease remains controversial. Hypotheses that link mutations in CFTR and defects in ion transport to CF lung disease predict that alterations in airway surface liquid (ASL) isotonic volume, or ion composition, are critically important. ASL [Cl-] is pivotal in discriminating between these hypotheses, but there is no consensus on this value given the difficulty in measuring [Cl-] in the "thin" ASL (approximately 30 microm) in vivo. Consequently, a miniaturized solid-state electrode with a shallow depth of immersion was constructed to measure ASL [Cl-] in vivo. In initial experiments, the electrode measured [Cl-] in physiologic salt solutions, small volume (7.6 microl) test solutions, and in in vitro cell culture models, with > or =93% accuracy. Based on discrepancies in reported values and/or absence of data, ASL Cl- measurements were made in the following airway regions and species. First, ASL [Cl-] was measured in normal human nasal cavity and averaged 117.3 +/- 11.2 mM (n = 6). Second, ASL [Cl-] measured in large airway (tracheobronchial) regions were as follows: rabbit trachea and bronchus = 114.3 +/- 1.8 mM; (n = 6) and 126.9 +/- 1.7 mM; (n = 3), respectively; mouse trachea = 112.8 +/- 4.2 mM (n = 13); and monkey bronchus = 112.3 +/- 10.9 mM (n = 3). Third, Cl- measurements were made in small (1-2 mm) diameter airways of the rabbit (108.3 +/- 7.1 mM, n = 5) and monkey (128.5 +/- 6.8 mM, n = 3). The measured [Cl-], in excess of 100 mM throughout all airway regions tested in multiple species, is consistent with the isotonic volume hypothesis to describe ASL physiology.

Manufacture of strontium-82/rubidium-82 generators and quality control of rubidium-82 chloride for myocardial perfusion imaging in patients using positron emission tomography.

We describe a protocol to manufacture 82Sr/82Rb generators and 82RbCl for myocardial imaging with PET. The generators are manufactured in 3 stages: (1) preparation of a tin oxide column, (2) leak test of the generator column and (3) loading of the generator with 82Sr. The generators produced sterile and non-pyrogenic 82RbCl for i.v. injection. No significant 82Sr/85Sr breakthroughs were observed after elution with 20 1 of saline. The automated system delivered human doses of 82RbCl accurately.

Transferability of results obtained for sodium, potassium and chloride ions with different analysers.

In this study we have assessed transferability in seven different analysers commonly used in clinical chemistry laboratories to measure sodium, potassium and chloride ions. The inaccuracy and linearity of the techniques were satisfactory in most cases, and therefore all the equipment may be used in both pathological and normal ranges of the electrolytes evaluated. In most cases it was possible to correct the inaccuracy. The equipment which gave the best performance when analysing the three ions assessed after considering the Process Capability Index (CPI) and Performance Index (PI) was Nova-5. According to Hyltoft-Petersen's criteria, the results obtained for the three ions with the different analysers cannot be used indiscriminately, apart from potassium. However, after comparison of the results obtained by indirect potentiometry with those obtained by other techniques, we can conclude that the transferability of results is possible in almost every case, as standard deviation from regression (Sy,x) was lower than the permissible analytical error.

Quantification of chloride in sweat with the Cystic Fibrosis Indicator System.

We examined the relation between chloride concentration and the area of complexed chloride of Medtronic's Cystic Fibrosis Indicator System, using a high-resolution x-y coordinated digitizer to measure the circumference of the chloride precipitation ring. These digitized points were entered directly into an IBM PC computer, where the area of the chloride precipitation was calculated with use of a repetitive rectangular estimation program. Using these data, we determined the relationship between the area of chloride precipitation and the chloride concentration of the standard NaCl solutions. When the area of the ring of chloride precipitation in the system's patch is measured immediately after the sweat test is completed, the concentration of chloride in the sweat can be calculated with a reproducibility equal to that of the Gibson-Cooke sweat test.

Japanese minimum requirements for albumin preparations: recent amendments and current problems.

The following amendments have been introduced to the Minimum Requirements for Human Serum Albumin (HSA) and Plasma Protein Fraction (PPF): 1) The upper limit of sodium content was fixed at 3.7 mg/ml; 2) test for chloride content was introduced; 3) sodium and chloride contents were required to be stated on the label; 4) use of zone electrophoresis was introduced in addition to the free-boundary electrophoresis; and 5) albumin content in HSA was lowered from 97% to 96%. Moreover, current problems in quality control which may require further amendments were discussed, namely: 1) limulus amoebocyte lysate test to replace or supplement the pyrogen test in rabbits; 2) attempt of quantitative expression of visual turbidity; 3) establishment of reference A and B blood group substances; 4) gel permeation analysis and scanning at 370-800 nm; and 5) test for prekallikrein activator (PKA).

An aqueous primary standard for use with the Technicon SMA 6/60.

An aqueous primary standard containing sodium, potassium, chloride, carbon dioxide, glucose, and creatinine was prepared for use with the Technicon SMA 6/60 continuous-flow analyzer. This standard, compared with a protein-base primary standard, showed no significant difference in slope, gamma-intercept, and linearity for these methods. Precision with use of the aqueous primary standard was acceptable, comparable to that for a commercial reference serum. The standard was stable for at least 30 days.