Hydrogeochemical Characteristics of Uranium and Radon in Groundwater from the Goesan Area of the Ogcheon Metamorphic Belt (OMB), Korea

Uranium and radon concentrations in groundwater from the Goesan area of the Ogcheon Metamorphic Belt (OMB), central Korea, whose bedrock is known to contain the highest uranium levels in Korea, were analyzed from 200 wells. We also measured the uranium concentrations in the bedrock near the investigated wells to infer a relationship between the bedrock geology and the groundwater. The five geologic bedrock units in the Goesan area consist of Cretaceous granite (Kgr), Jurassic granite (Jgr) and three types of metasedimentary rocks (og1, og2, and og3). The percentages of the groundwater samples over 30 μg/L (maximum contaminant level, MCL of US EPA) were 2.0% of the 200 groundwater samples; 12% of Kgr and 1.8% of Jgr exceeded the MCL, respectively. Overall, 16.5% of the 200 groundwater samples exceeded 148 Bq/L (alternative maximum contaminant level, AMCL of US EPA); 60.0% of Kgr and 25.0% of Jgr exceeded the AMCL, but only 0% of og1, 7.9% of og2, and 2.6% of og3 exceeded the value, respectively. No direct correlation was found between uranium concentration and radon concentration in water samples. Radon has a slightly linear correlation with Na (0.31), Mg (−0.30), and F (0.36). However, uranium behavior in groundwater was independent of other components. Based on thermodynamic calculation, uranium chemical speciation was dominated by carbonate complexes, namely the Ca2UO2(CO3)3(aq) and CaUO2(CO3)32− species. Although uraniferous mineral phases designated as saturation indices were greatly undersaturated, uranium hydroxides such as schoepite, UO2(OH)2 and U(OH)3 became possible phases. Uranium-containing bedrock in OMB did not significantly affect radioactive levels in the groundwater, possibly due to adsorption effects related to organic matter and geochemical reduction. Nevertheless, oxidation prevention of uranium-containing bedrock needs to be systematically managed for monitoring the possible migration of uranium into groundwater.

Evaluation of Microbial and Elemental contaminants of Open Market Sachet Water in Nnewi Metropolis

This Study Assessed Microbial And Elemental Constituents Of Sachet Drinking Water In Nnewi Metropolis. 100 Questionnaires Were Administered To Get Responses Of Individuals Who Frequently Drink Sachet Water And Cross-Sectional Study Was Conducted Using 10 Sachet Water Samples Collected From Nnewi. Each Sample Was Subjected To Physicochemical Examinations And Microbiological Examination. Data Were Analyzed Using Descriptive And ANOVA. 29% Respondents Reported Developing Some Symptoms After Drinking A Particular Brand Or Different Brands. 60% Of Samples Had Mercury Levels Exceeding The Maximum Contaminant Level Of 0.006mg/L, While All Samples Had Lead Levels Exceeding Maximum Contaminant Level Of 0.01mg/L. Microbial Test Revealed Bacterial Contamination In All Brands And Protozoon Contamination In One. Study Concluded That Sachet Water Is Unfit For Drinking Due To High Levels Of Elemental Constituents And Bacterial Contamination. It Therefore, Highlight The Need For Government Agencies To Intensify Surveillance And Enforce Stringent Hygienic Measures To Sachet Water Industries/Retail Outlets.

Assessment of Some Heavy Metals and Physico-Chemical Parameters of Surface Water of Matara-Uku Wetlands

The study assessed the levels of Nitrogen, Phosphorous and some heavy metals in Matara-Uku wetland. Twenty water samples were collected from surface water of Matara-Uku using polyethene plastic container, the physicochemical parameters of the samples were measured and the samples were analyzed for Nitrogen, Phosphorous and heavy metals. Results from physicochemical analysis are obtained as; pH (7.6 – 8.0), total dissolve solid (70.82 - 84.26 mg/l), electric conductivity (105.0 – 163.0 μs/cm) and temperature (24.4 – 25.4ºC). All the results are in line with World Health Organization standard of 6.5 - 8.5, <600 mg/l, 400 μs/cm and ambient temperature respectively. The Nitrogen and phosphorous were analyzed using UV- Visible spectrophotometer. From the results, it was found that all the samples had Nitrogen level below the World Health Organization maximum contaminant level of 10 mg/L with a mean concentration range (0.2293 ± 0.0057) mg/L to (2.2455 ± 0.0216) mg/L. Phosphorus was also analyzed and the results indicated that all the sampling sites had phosphorus level above the WHO maximum contaminant level of 0.03 mg/L with a mean concentration range (3.8208 ± 0.4109) mg/L to (4.56 ± 0.1325) mg/L. The water samples were digested using concentrated HCl and HNO3, in which the digested samples were used for heavy metals analysis using Atomic Absorption Spectrophotometer (AAS). The mean concentrations of the heavy metals analyzed were between the ranges Pb (0.1272 ± 0.0445) mg/L to (0.2727 ± 0.1285) mg/L, Cd (0.0026 ± 0.0024) mg/L to (0.0053 ± 0.0054) mg/L and Ni (0.0705 ± 0.0235) mg/L to (0.1411 ± 0.0819) mg/L respectively. Concentrations of Cd and Ni are generally below the maximum permissible limit of 0.03 mg/L and 0.02 mg/L, whereas concentrations of Pb exceeded the maximum permissible limit of 0.01 mg/L for surface water. It was concluded that the surface water of Matara-Uku is polluted with respect to Pb, which is known to bio-accumulate and even undergo bio-magnification in organisms such as fishes and even plants with serious health implications to human being.

Analysis of health risk and respiratory complaints on footwear craftsman exposed to Toluene vapour

Background: The primary effect of toluene on the respiratory tract following inhalation is irritation. This study was conducted to analyze the level of health risks and respiratory complaints due to toluene exposure by footwear craftsmen, in order to get scientific reference for Maximum Contaminant Level and working tenure restriction. Design and Methods: A total of 51 footwear craftsmen from eight factories participated in this study. The toluene concentration in the work environment was measured according to National Institute of Occupational Safety and Health 1501. Moreover, data were collected using an American Thoracic Society standardized questionnaire to assess respiratory health effects. A characterization of risk model was to analyze the toluene exposure risk and suggest improvements. Results: The results showed toluene levels were over the Threshold Limit Value 20 ppm (138.88 ppm). The most commonly observed respiratory symptoms included coughing by 81.3% and cold by 85.7%, Symptoms of respiratory irritation by 72.7%, higher among workers who were highly exposed to toluene above the median. This is observed from the opportunity value (P-value) of toluene exposure with the characteristics the workers of each variable which was less than 0.05 work station and working tenure. Maximum Contaminant Level of toluene is 4.59 ppm, a safe working tenure restriction for toluene exposure is maximum 25 years. Conclusions: The recommended risk control measures include ventilation improvements, personal hygiene and protection of workers through periodic physical examinations.

Geochemical Behavior of Uranium and Radon in Groundwater of Jurassic Granite Area, Icheon, Middle Korea

Uranium concentrations (a total of 82 samples) in groundwater in Icheon, middle Korea, showed a wide range from 0.02 to 1640 μg/L with a mean of 56.77 μg/L, a median of 3.03 μg/L, and a standard deviation of 228.63 μg/L. Most groundwater samples had quite low concentrations: 32.9% were below 1 μg/L, while 15.9% exceeded 30 μg/L, the maximum contaminant level (MCL) of the US EPA (Environmental Protection Agency). Radon concentrations also ranged widely from 1.48 to 865.8 Bq/L. Although the standard deviation of radon was large (151.8 Bq/L), the mean was 211.29 Bq/L and the median was 176.86 Bq/L. Overall, 64.6% of the samples exceeded the alternative maximum contaminant level (AMCL) of the US EPA (148 Bq/L). According to statistical analyses, there was no close correlations between uranium and radon, but there were correlations between uranium and redox potential (Eh) (−0.54), dissolved oxygen (DO) (−0.50), HCO3− (0.45), Sr (0.65), and SiO2 (−0.44). Radon showed independent behavior with respect to most components in groundwater. Uranium concentrations in groundwater increased with increasing water–rock interactions. Anomalously high uranium and radon concentrations in groundwater are preferentially localized in granite areas and spatial distributions are remarkably heterogeneous.