Speciation of Ions in Groundwater and its Applications

Speciation of ions in groundwater is very important to understand its hydrogeochemical evolutions from its origin to its present status. The speciation will help to understand the geochemical process which controls their evolution and their present day environmental conditions which will ultimately lead us to utilize them directly or after the required treatment process to make them safe and useable. Some of the ions and their speciation were discussed in this line in this chapter

Hydrogeochemical Modeling of Groundwater in the Gadilam River Basin, South India

Hydrogeochemistry of a region is a reflection of hydrodynamic process, composition of lithology and physical constraints. The water chemistry is the resultant of all biogeochemical processes and reactions, which have acted on water from the moment it has condensed in atmosphere till the time it's discharged. A case study has been carried out in a varied lithological terrain with Archaean, Alluvium and Tertiary rocks to unravel the hydrogeochemical process. The dominant facies in the entire litho units is sodium - chloride type indicating saline nature in the groundwater. The speciation of bicarbonate, sulphate and phosphate in the groundwater samples in different litho units was determined using the computer program WATQ4F. This study reveals that higher speciation with increasing concentration of bicarbonate in summer and south west monsoon indicates static environment, whereas lesser speciation in north east monsoon and post monsoon indicates flushing environment in the basin. Higher speciation with lesser contribution of sulphate in summer and south west monsoon and an increasing trend of speciation in north east monsoon and post monsoon was observed

A nutrigenetic approach to investigate the relationship between metabolic traits and vitamin D status in an Asian Indian population

Studies in Asian Indians have examined the association of metabolic traits with vitamin D status. However, findings have been quite inconsistent. Hence, we aimed to explore the relationship between metabolic traits and 25-hydroxyvitamin D [25(OH)D] concentrations. We investigate whether this relationship was modified by lifestyle factors using a nutrigenetic approach in 545 Asian Indians randomly selected from the Chennai Urban Rural Epidemiology Study (219 normal glucose tolerant individuals, 151 with pre-diabetes and 175 individuals with type 2 diabetes). A metabolic genetic risk score (GRS) was developed using five common metabolic disease-related genetic variants. There was a significant interaction between metabolic GRS and carbohydrate intake (energy%) on 25(OH)D (Pinteraction = 0.047). Individuals consuming a low carbohydrate diet (≤62%) and those having lesser number of metabolic risk alleles (GRS ≤ 1) had significantly higher levels of 25(OH)D (p = 0.033). Conversely, individuals consuming a high carbohydrate diet despite having lesser number of risk alleles did not show a significant increase in 25(OH)D (p = 0.662). In summary, our findings show that individuals carrying a smaller number of metabolic risk alleles are likely to have higher 25(OH)D levels if they consume a low carbohydrate diet. These data support the current dietary carbohydrate recommendations of 50%–60% energy suggesting that reduced metabolic genetic risk increases 25(OH)D

Baseline survey of environmental parameters, radiation, and drip water hydrochemistry in Niah Caves (Sarawak, Malaysia)

Relict caves in fenglin karst may typically have numerous entrances and openings. Hence, they host a variety of environments in which parameters such as light, airflow, humidity, and temperature may vary significantly over short distances. Similarly, drip water hydrochemistry, including isotopic values, may vary due to different contributions of various sources and residence time in the karst. This study investigated environmental parameters, including radiation, using hand-held instruments, along a transect within several major caves in the Niah karst of Sarawak (Malaysia). This has led to a baseline data set which showed an inverse relationship between humidity and temperature, gamma radiation levels that are about 25% of that in surrounding non-karst region, and high percentages of twilight zones in the studied caves. Airflow was found to be variable, with high values of 530 m3/s in Painted Cave and 122 m2/s in parts of Gan Kira passage, with flow towards the southeast at the time of the study. The hydrochemistry of the drip water and surface water was also analyzed and found to be dominantly Ca–Mg–Cl water type which indicates dissolution of minerals through water–rock interaction. In addition, the cave environment, particularly air temperature, humidity, and ventilation, also influences the drip water composition and isotopic values. Three different origins (precipitation, evaporation, and paleo-recharge) of drip water have been identified through the δ18O-δ2H diagram. Enriched isotopic values were observed in the cave entrance due to increased evaporation caused by lower humidity and higher air temperature. Factor analysis identifies the key geochemical processes responsible for the drip water chemistry. The outcome of this study provides the first baseline environmental data for the Niah caves, which could support future initiatives for sustainable management of this famous archeological site in southeast Asia

Association of depression with complications of type 2 diabetes - the Chennai Urban Rural Epidemiology Study (CURES - 102)

Objective: The aim of the study was to assess the relationship between depression and diabetic complications among urban south Indian type 2 diabetic subjects [T2DM]. Methods: T2DM subjects [n= 847] were recruited from the Chennai Urban Rural Epidemiology Study [CURES], a population based study in Chennai (formerly Madras) in South India. A previously validated depression questionnaire [PHQ-12 item] was administered. Four field stereo retinal colour photography was done and diabetic retinopathy [DR] was classified according to the Early Treatment Diabetic Retinopathy Study grading system. Neuropathy was diagnosed if the vibratory perception threshold of the right great toe, measured by biothesiometry, was ≥20. Nephropathy was diagnosed if urinary albumin excretion was ≥300 μg/mg creatinine. Peripheral vascular disease [PVD] was diagnosed if an ankle-brachial index was <0.9. Coronary artery disease [CAD] was diagnosed based on a past history of documented myocardial infarction and/or electrocardiographic evidence of Q wave and/or ST segment changes. Results: Of the 847 T2DM studied, 198 (23.4%) were found have depression. The prevalence of depression was significantly higher among diabetic subjects with DR (35.0% vs 21.1%,p<0.001), neuropathy (28.4% vs15.9%,p=0.023), nephropathy (35.6% vs 24.5%,p=0.04) and PVD (48.0% vs 27.4%,p<0.001) as compared to subjects without these complications. DR, neuropathy, nephropathy, and PVD were associated with depression even after adjusting for age, gender, duration of diabetes and glycated haemoglobin. DR (Odds ratio [OR] =2.19, Confidence interval [CI]:1.45-3.51,p<0.001) was associated with depression even after adjusting for neuropathy and nephropathy. There was also a significant association between depression and neuropathy, after adjusting for retinopathy and nephropathy (OR=2.07,CI:1.41-3.04,p<0.001). There was a significant association of depression with nephropathy but this was lost (OR=1.71, CI: 0.87-3.35,p=0.119) after adjustment for retinopathy. PVD (OR=3.52,CI:1.94- 6.40,p<0.001) remained significantly associated with depression even after adjusting for CAD. However, there was no significant association of depression with CAD (OR=0.73, CI:0.42 -1.27, p=0.264). Conclusion: Among Asian Indians, the prevalence of depression is higher in T2DM subjects with retinopathy, neuropathy, nephropathy and PVD compared to those without the respective complications

Studies on maturity onset diabetes of the young (MODY) from S. India

We examined the following aspects of Maturity Onset Diabetes of the Young (MODY): prevalence, vascular complications, insulin secretion in offspring of MODY subjects, insulin resistance and whether MODY can be considered a distinct disease. We report a higher prevalence of MODY among Asian Indian patients. The prevalence rates of microvascular complications in MODY were found to be the same as in classical NIDDM patients. Glucose stimulated insulin and C-peptide responses were compared with non-diabetic controls. In MODY subjects, C-peptide responses were lower, whereas insulin responses were varied. Insulin secretion in offspring of MODY subjects was similarly evaluated, and abnormalities discovered even in these prediabetic subjects. Using the euglycaemic clamp technique, MODY patients were found to be more insulin resistant than classical NIDDM patients. Further lines of evidence are needed to resolve whether MODY can be considered a distinct disease

A Novel Approach for Groundwater Budgeting Using GIS in a Part of Pondicherry Region, India

The over extraction of groundwater from the coastal aquifers, result in reduction of groundwater resource and lowering of water level. In general, the depletion of groundwater level enhances the landward migration of saltwater wedge. Pondicherry is one such region with recent alluvium as the major formation. Since the study area forms a part of the coastal aquifer system this behaves as a fragile ecosystem. The present study has been attempted to calculate the extraction of water and to estimate the amount of recharge into this allu-vial aquifer by using groundwater level variations. The monthly water level fluctuation was observed during the study period (2000-2002) in eighteen locations. The maximum rise in groundwater level observed during 2000 was considered as the initial water level for the study and the subsequent decline in water level (draw down) was monitored monthly until the rising trend was noted. This indicates the fall in water level due to extraction.Later keeping the deepest draw down as the initial value increasing water level trend was studied until there was a notice of decline in groundwater level. This indicates as the rise in water level due to re-charge. This method of observation carried out at a single location was adopted for all eighteen locations. The spatial representation of these data for eighteen locations were carried out by using GIS and the area occupied by different groundwater level contours were calculated and the amount of water withdrawn/re- charged was estimated. The maximum recharge was noted in the central and the northern part of the study area when compared to the other regions. Similarly, the maximum discharge was noted in the northern and the southern part of the study area during the study period