Revealing drinking water quality issues and possible health risks based on water quality index (WQI) method in the Shanmuganadhi River basin of South India.

The aim of the study is to address the issues and associated health risks due to consumption of high-fluoride water supplied for drinking in a rural part of Shanmuganadhi River basin, Tamil Nadu, India. In this study, 61 groundwater samples were gathered from various tube and open wells and analysed for fluoride and other physicochemical parameters. The abundance of cations is Na+ > Ca2+ > Mg2+ > K+, and that of anions is HCO3- > SO42- > Cl- > F-. The fluoride concentration in drinking groundwater varied from 0.10 to 3.3 mg/l. According to the WHO standards, about 26% of the samples were unfit for drinking requirements (16 out of 61 samples) Water quality index (WQI) method was adopted to categorize the water into different classes to understand its suitability for drinking requirements. WQI signified that nearly 52% of the samples denoted poor, very poor and not suitable categories, whereas 48% of samples denoted good and excellent categories for consumption. Health risks associated with high-fluoride drinking water were assessed for various age groups of inhabitants such as children, teens and adults. The hazard quotient estimated based on the oral intake ranged from 0.00E+00 to 5.50E+00, from 0.00E+00 to 4.22E+00 and from 0.00E+00 to 3.45E+00 for children, teens and adults, respectively. It suggested that the health risks are associated with 75%, 59% and 43% of samples, respectively, among children, teens and adults. Therefore, children are more inclined towards risk than teens and adults in this region based on the intake of fluoride-rich drinking water. To improve the present scenario, groundwater should be either treated before drinking water supply or must be artificially recharged to lower the concentration of ions.

Validation and application of an HPLC-CAD-TOF/MS method for identification and quantification of pharmaceutical counterions.

A generic approach for the analysis of counterions of pharmaceutical reference substances, which are established by the laboratory department of the European Pharmacopoeia (Ph. Eur.), was developed. A mixed-mode chromatography method using charged aerosol detection (CAD) published by Zhang et al. separating 25 commonly used pharmaceutical counterions was selected for this purpose. The method was validated in terms of specificity, repeatability, limits of quantification (LOQs), linearity and range according to ICH guideline Q2(R1) and the Technical Guide for the Elaboration of Monographs of the Ph. Eur. Moreover, the applicability of the method for the purpose of counterion identification and quantification in drug substances as well as for the control of inorganic ions as impurities was demonstrated using selected examples of Ph. Eur. reference standards and other samples of substances for pharmaceutical use (e.g. cloxacillin sodium, somatostatin). It was shown that for identification purposes of the parent substance as well as organic ions the chromatographic system can easily be coupled to a mass selective detector without any modification.