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1.
Ecotoxicol Environ Saf ; 213: 112073, 2021 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-33639561

RESUMEN

Seasonal variations in hydrogeochemical characteristics of groundwater were assessed from an intensive agricultural region to identify contaminants of concern that are a potential risk to human health. A total of 116 groundwater samples were collected grid-wise from an intensive agricultural region of confined Wanaparthy watershed to evaluate seasonal variations in hydrogeochemical processes of dissolved ions, nitrate health risk assessment and water quality during pre-monsoon (PRM) and post-monsoon (POM) seasons. The major ions concentration found in ascending order as PRM: F- < NO3-< SO42-< HCO3-< Cl- and K+< Mg+2< Ca+2< Na+ while POM: F- < NO3-< SO42-< Cl-< HCO3- and K+< Ca+2< Mg+2< Na+ respectively. Piper diagram for water-types shows PRM; Na-Cl type (70.68%) while POM; Ca-Mg-Cl type (39.66%) and Ca-HCO3 type (31.03%). Gibbs diagram explained the favorable environmental conditions as rock and evaporation dominance in both seasons. Spatial distribution map shows samples with higher and above permissible limits are found at/near to adjoining to higher-order streams and streams origin. As per the water quality index (WQI), 36.21% (PRM) and 60.34% (POM) fall in poor to unfit for drinking class. Hazard quotient (HQ) values of nitrate reach as high as for infants 1.31E + 01, children 1.23E + 01 and adults 4.68E + 00 respectively. Subsequently, HQ>1 with 68.97% of infants and 72.41% of children are in danger for non-carcinogenic ingestion of nitrate contaminated groundwater than in adults.


Asunto(s)
Monitoreo del Ambiente , Contaminantes Químicos del Agua/análisis , Adulto , Agricultura , Niño , Fluoruros/análisis , Agua Subterránea , Humanos , India , Lactante , Nitratos/análisis , Medición de Riesgo , Ríos/química , Estaciones del Año , Sodio , Calidad del Agua/normas
2.
Arch Environ Contam Toxicol ; 80(1): 31-40, 2021 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-33388839

RESUMEN

In this study, the quality of groundwater was assessed in a semi-arid region of India by using an entropy weighted water quality index (EWQI) and a pollution index of groundwater (PIG). The EWQI and PIG methods were used to evaluate data on physicochemical parameters in relation to drinking water quality standards. Groundwater samples were collected from the Dubbak region, Telangana state, India, and were analyzed for pH, total hardness, electrical conductivity, total dissolved solids, bicarbonate (HCO3-), chloride (Cl-), sulfate (SO42-), nitrate (NO3-), fluoride (F-), calcium (Ca2+), magnesium (Mg2+), sodium (Na+), and potassium (K+). The groundwater of the study region is alkaline in nature. The abundance of cations and anions based on their mean values is in the following order: Na+ > Ca2+ > Mg2+ > K+ and Cl- > HCO3- > NO3- > SO42- > F-, respectively. The calculated EWQI values ranged from 49.0 to 174.6, with an average of 93.3. Overall, EWQI data showed that only 60% of groundwater samples were of suitable quality for drinking, although only marginally, whereas the remaining 40% of samples were unsuitable for drinking purposes and would therefore require treatment. The values of PIG varied from 0.5 to 1.8, with an average of 1.0, which showed that only 63% of groundwater samples from the study area were suitable for drinking purposes.


Asunto(s)
Agua Potable/normas , Entropía , Monitoreo del Ambiente/métodos , Agua Subterránea/química , Contaminantes Químicos del Agua/análisis , Calidad del Agua/normas , Cloruros/análisis , Fluoruros/análisis , India , Magnesio/análisis , Minerales/análisis , Nitratos/análisis , Salud Rural , Sulfatos/análisis
3.
Arch Environ Contam Toxicol ; 80(1): 294-307, 2021 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-33388840

RESUMEN

Exposure to fluoride concentrations above a threshold of 1.5 mg/L can cause joint pains, restricted mobility, skeletal and dental fluorosis. This study aims to determine the hydrochemical evolution of the fluoride-rich groundwater and estimate the risk of fluoride exposure to the residents of semi-arid northeastern part of Rajasthan, India. The methodology involves measurement of fluoride and other ionic concentrations in groundwater using ion chromatography, followed by an estimation of the cumulative density function and fluorosis risk. The fluoride concentration in water samples varied from 0.04 to 8.2 mg/L with 85% samples falling above the permissible limit. The empirical cumulative density function was used to estimate the percentage and degree of health risks associated with the consumption of F- contaminated water. It is found that 55% of the samples indicate risk of dental fluorosis, 42% indicate risk of deformities to knee and hip bones, and 18% indicate risk of crippling fluorosis. In addition, instances of high nitrate concentrations above the permissible limit of 45 mg/L are also found in 13% of samples. The fluoride rich groundwater is mainly associated with the Na-HCO3-Cl type water facies while low fluoride groundwater shows varied chemical facies. The saturation index values indicate a high probability of a further increase in F- concentration in groundwater of this region. The calculated fluoride exposure risk for the general public in the study area is 3-6 times higher than the allowed limit of 0.05 mg/kg/day. Based on the results of this study, a fluorosis index map was prepared for the study area. The northern and northeastern parts are less prone to fluorosis, whereas the south-central and southwestern parts are highly vulnerable to fluorosis. The inferences from this study help to prioritize the regions that need immediate attention for remediation.


Asunto(s)
Agua Potable/química , Monitoreo del Ambiente/métodos , Fluoruros/análisis , Agua Subterránea/química , Contaminantes Químicos del Agua/análisis , Enfermedades Óseas/epidemiología , Clima , Fluoruros/efectos adversos , Fluorosis Dental/epidemiología , Humanos , India , Nitratos/efectos adversos , Nitratos/análisis , Medición de Riesgo , Contaminantes Químicos del Agua/efectos adversos
4.
Arch Environ Contam Toxicol ; 80(1): 277-293, 2021 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-33392776

RESUMEN

The main focus of the present research was to examine the appropriateness of groundwater resources for drinking purposes in the Bilate River Basin of Southern Main Ethiopian Rift, Ethiopia. The groundwater quality index (GWQI), fluoride pollution index (FPI), and human health risk were used to examine the human health risk factors associated with the intake of high fluoride groundwater. For this purpose, 29 groundwater samples were collected from the existing wells and were analyzed for various physicochemical parameters. The dominant cation was Na+, followed by Ca2+, Mg2+, and K+. The dominant anion was HCO3-, followed by Cl-, SO42-, and F-. The Gibbs plot shows that rock-water interactions are the dominant factor controlling the groundwater chemistry. By using the GWQI, the quality of groundwater samples was 31% excellent, 21% good, 31% poor, and 17% very poor. The fluoride concentration in groundwater ranges from 0.2 to 5.60 mg/L (mean, 2.10 mg/L). 59% (i.e., 17 wells) of the groundwater samples were not suitable for drinking, because they surpassed the drinking water quality limit of 1.5 mg/L. The remaining 41% (i.e., 12 wells) of the samples were suitable for drinking. The FPI indicates that 51.72% of the wells were highly polluted by fluoride. The noncarcinogenic health risk varies from 0.75 to 8.44 for children (83%), 0.34-3.84 for women (62%), and 0.27-3.01 for men (52%), which indicates that children are at higher health risk than women and men due to the physiological condition and the rates of ingestion.


Asunto(s)
Monitoreo del Ambiente/métodos , Fluoruros/análisis , Sedimentos Geológicos/química , Agua Subterránea/química , Ríos/química , Contaminantes Químicos del Agua/análisis , Adulto , Altitud , Niño , Agua Potable/análisis , Agua Potable/normas , Etiopía , Femenino , Sistemas de Información Geográfica , Humanos , Masculino , Medición de Riesgo , Calidad del Agua/normas
5.
Ecotoxicol Environ Saf ; 208: 111548, 2021 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-33396092

RESUMEN

In order to understand the pollution status of groundwater with geochemical evolution and appraisal of its probable public health risk due to nitrate (NO3-) and fluoride (F-), a total of 93 groundwater samples were collected during pre-monsoon (May) period from Wardha sub-basin, central India. By employing Piper plot, transition from Ca-HCO3 type water (recharge waters) to Na-Cl (saline water) type water through mixed Ca-Na-HCO3, mixed Ca-Mg-Cl (reverse ion exchange waters) and Ca-Cl types (leachate waters), were observed. The Geogenic processes such as silicate, dolomite, halite and carbonate weathering along with calcite precipitation and ion exchange process were identified as major controlling factors for evolution and alteration of groundwater chemistry. The Saturation index highlighted that the groundwater in the area is oversaturated with respect to the mineral calcite and dolomite, and under saturated with gypsum, fluorite and halite. The high NO3- and F- concentration overpassing the permissible limit were found in 54.8% and 18.5% of samples. The plot of F- with Na+/Ca2+, Na+/Mg2+ and F-/Cl- established fluoride bearing rock weathering is responsible for F- contamination. Based on the cluster analysis, the groundwater was grouped into Cluster-I Ca-Na-HCO3 type (61.3%) and Cluster-II Na-Ca-HCO3-Cl type (30.1%). The total hazard index (HI) based on human health risk assessment (HHRA) model for cumulative NO3- and F- toxicity through oral and dermal pathways were computed as 100%, 97.85% and 96.77% for children, female and male populations respectively. The HQ(nitrate) > 1 through ingestion pathway were in 84.95%, 68.82% and 62.37%, and HQ(fluoride) > 1 in 83.87%, 62.37% and 43.01% of the groundwater samples were recorded for children, female and male population respectively. The risk assessment study highlighted very high toxicity and severe health impact of ingestion of contaminated groundwater on public health.


Asunto(s)
Monitoreo del Ambiente , Fluoruros/toxicidad , Nitratos/toxicidad , Contaminantes Químicos del Agua/toxicidad , Carbonato de Calcio , Carbonatos , Niño , Femenino , Fluoruros/análisis , Agua Subterránea/análisis , Agua Subterránea/química , Humanos , India , Intercambio Iónico , Magnesio , Nitratos/análisis , Medición de Riesgo , Contaminantes Químicos del Agua/análisis
6.
Ecotoxicol Environ Saf ; 208: 111670, 2021 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-33396180

RESUMEN

Exposure to excessive fluoride has been associated with a number of adverse health outcomes; however, there is a lack of evidence on the relation between fluoride exposure and serum uric acid levels, especially in human populations. The present study examined a potential relationship between fluoride exposure, measured as both plasma and water fluoride concentrations, and uric acid levels in an adolescent population. A nationally representative subsample of 1933 adolescents, aged 12-19 years, in the 2013-2016 National Health and Nutrition Examination Survey was analyzed for the association of fluoride concentrations with serum uric acid levels using multivariate general linear and logistic regression models, adjusting for potential confounders. Since uric acid levels change during development, hyperuricemia was defined in this study as over the mean plus one standard deviation for each sex and age group of adolescents. Of the study participants, 276 adolescents (weighted prevalence, 16.56%) had hyperuricemia. A significant and dose-dependent increase in prevalence of hyperuricemia was seen among the participants cross increasing quartiles of plasma fluoride (p-trend = 0.0017). After adjusting for potential confounders, we found that adolescents in the higher quartiles of plasma fluoride (≥0.32 µmol/L) and in the highest quartile of water fluoride (≥0.73 mg/L) had significantly increased odds of hyperuricemia compared with those in the lowest quartile. A 1.95-fold increased odds (95% CI: 1.37, 2.77) of hyperuricemia was also observed when analyzing plasma fluoride concentrations as continuous variable. A general linear model revealed that a 1 µmol/L increase in ln-plasma fluoride was associated with a 0.212 mg/dL (p < 0.0001) increased serum uric acid level. Furthermore, a positive relationship was observed between water and plasma fluoride concentrations (ß = 0.1907; p < 0.0001). Our study demonstrates a potential relation between fluoride exposure and hyperuricemia in adolescents. Further studies are warranted to overcome the limitations of this study to examine the impact of long-term exposure to low levels of fluoride during development on hyperuricemia and its related health outcomes.


Asunto(s)
Exposición Dietética/efectos adversos , Fluoruros/efectos adversos , Hiperuricemia/inducido químicamente , Adolescente , Niño , Estudios Transversales , Exposición Dietética/análisis , Exposición Dietética/estadística & datos numéricos , Relación Dosis-Respuesta a Droga , Agua Potable/química , Femenino , Fluoruros/análisis , Humanos , Hiperuricemia/sangre , Hiperuricemia/epidemiología , Masculino , Encuestas Nutricionales , Prevalencia , Estados Unidos/epidemiología , Adulto Joven
7.
Artículo en Inglés | MEDLINE | ID: mdl-33406716

RESUMEN

Fluorides are compounds that can be found in the minerals of soil with volcanic rocks. Different populations are exposed to high levels of fluorides through drinking water that, due to their chronic intake, cause several types of damage to health. Nails and hair, denominated as recent biomarkers, have been employed for monitoring systemic fluoride from long-term exposure to fluorides. The aim of this study was to perform a systematic review of the use of recent biomarkers for monitoring systemic fluoride levels in exposed populations and verify their validity in the measurement of the fluorine (F-) concentration within the body. A digital search was performed in the databases PubMed/Medline, Springer Link, Cochrane, and Scopus of original articles that employed recent biomarkers for monitoring systemic F-. Seventeen articles were included in this analysis; the recorded variables were the F- amount in each assessed biomarker, source of exposure, and total daily fluoride intake (TDFI). TDFI was associated with F- in nails and hair, as well as the exposure through drinking water. In conclusion, recent biomarkers are adequate for monitoring the systemic fluoride levels by evaluating the chronic/subchronic exposure through different sources, mainly drinking water, considering nails better than hair for this purpose.


Asunto(s)
Biomarcadores/análisis , Agua Potable , Fluoruros/análisis , Estudios Transversales , Agua Potable/análisis , Exposición a Riesgos Ambientales/análisis , Cabello/química , Humanos , Uñas/química
8.
Arch Environ Contam Toxicol ; 80(1): 259-276, 2021 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-33398395

RESUMEN

Samples of groundwater were collected during a post-monsoon period (January) and a pre-monsoon period (May) in 2020 from 30 locations in the rapidly developing industrial and residential area of the Coimbatore region in southern India. These sampling periods coincided with times before and during the lockdown in industrial activity and reduced agricultural activity that occurred in the region due to the COVID-19 pandemic. This provided a unique opportunity to evaluate the effects of reduced anthropogenic activity on groundwater quality. Approximately 17% of the wells affected by high fluoride concentrations in the post-monsoon period returned to levels suitable for human consumption in samples collected in the pre-monsoon period. This was probably due to ion exchange processes, infiltration of rainwater during the seasonal monsoon that diluted concentrations of ions including geogenic fluoride, as well as a reduction in anthropogenic inputs during the lockdown. The total hazard index for fluoride in the post-monsoon samples calculated for children, adult women, and adult men indicated that 73%, 60%, and 50% of the groundwater samples, respectively, had fluoride levels higher than the permissible limit. In this study, nitrate pollution declined by 33.4% by the pre-monsoon period relative to the post-monsoon period. The chemical facies of groundwater reverted from the Na-HCO3-Cl and Na-Cl to the Ca-HCO3 type in pre-monsoon samples. Various geogenic indicators like molar ratios, inter-ionic relations along with graphical tools demonstrated that plagioclase mineral weathering, carbonate dissolution, reverse ion exchange, and anthropogenic inputs are influencing the groundwater chemistry of this region. These findings were further supported by the saturation index assessed for the post- and pre-monsoon samples. COVID-19 lockdown considerably reduced groundwater pollution by Na+, K+, Cl-, NO3¯, and F- ions due to shutdown of industries and reduced agricultural activities. Further groundwater quality improvement during lockdown period there is evidence that the COVID-19 lockdown by increased HCO3¯ ion concentration. Overall results illustrate the positive benefits to groundwater quality that could occur as a result of measures to control anthropogenic inputs of pollutants.


Asunto(s)
Agua Subterránea/química , Cuarentena , Estaciones del Año , Contaminantes Químicos del Agua/efectos adversos , Contaminantes Químicos del Agua/análisis , Contaminación Química del Agua/efectos adversos , Adulto , Factores de Edad , Agricultura , Niño , Control de Enfermedades Transmisibles , Monitoreo del Ambiente , Femenino , Fluoruros/análisis , Humanos , India , Industrias , Masculino , Nitratos/análisis , Pandemias , Medición de Riesgo , Factores Sexuales
9.
Ecotoxicol Environ Saf ; 211: 111926, 2021 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-33472111

RESUMEN

Groundwater from deep confined aquifers is often recommended for use because of it's low fluoride health risk. Thus, this study appraised groundwater fluoride hydrochemistry in a multi-aquifer system in Jilin Qianan to determine the non-carcinogenic health risk liable from exploiting the respective aquifers. 124 samples collected from the tertiary confined aquifer (N), quaternary confined aquifer (Q1), and quaternary phreatic aquifer (Q3) during surveys in 2001 and 2017 was analyzed using hydrochemical, statistical, spatial, and health risk assessment methods. Results show that the dominant water facies in the respective aquifer layers was Na+K-HCO3+CO3 except in Q1, where Ca+Mg - HCO3 + CO3 was marginally dominant. Fluoride concentrations outside the recommended guideline occurred in all the aquifers except N, where concentrations were optimum. The mean fluoride concentration of groundwater in the aquifers was of the order Q3 (2017) > Q3 (2001) > Q1 > N ( mean 2.09, 2.03, 1.41 and 0.75 mg/L with 51.85%, 57.44%, 36.36% and 0% occurring beyond recommended guideline values respectively). Silicate weathering, cation exchange, and fluorite dissolution in an alkaline environment were the significant fluoride contributing processes. Evaporation and MgF+ complex additionally influenced Q1 and Q3 (2017). The total hazard quotient (THQ) from oral and dermal pathways shows fluoride health risks in the order: infant > children > adult. The associated risks likely from using water in the respective aquifer layers is of the order Q3 (2017) > Q3 (2001) > Q1 > N. The mean groundwater fluoride in 2017 was marginally higher than that of 2001 ( 2.09>2.03 mg/L respectively) although the percentage of age group members disposed to fluoride risk from using water from Q3 decreased from 2001 to 2017. Knowledge of local hydrogeology in exploiting deep groundwater free of fluoride pollution and on-site defluoridation treatment of groundwater was recommended in the study area and other areas with similar characteristics.


Asunto(s)
Exposición a Riesgos Ambientales/estadística & datos numéricos , Monitoreo del Ambiente , Fluoruros/análisis , Contaminantes Químicos del Agua/análisis , Niño , China , Agua Subterránea/química , Humanos , Medición de Riesgo , Sodio
10.
J Sci Food Agric ; 101(2): 379-387, 2021 Jan 30.
Artículo en Inglés | MEDLINE | ID: mdl-32623727

RESUMEN

Tea is the one of the most popular non-alcoholic caffeinated beverages in the world. Tea is produced from the tea plant (Camellia sinensis (L.) O. Kuntze), which is known to accumulate fluoride. This article systematically analyzes the literature concerning fluoride absorption, transportation and fluoride tolerance mechanisms in tea plants. Fluoride bioavailability and exposure levels in tea infusions are also reviewed. The circulation of fluoride within the tea plantation ecosystems is in a positive equilibrium, with greater amounts of fluoride introduced to tea orchards than removed. Water extractable fluoride and magnesium chloride (MgCl2 ) extractable fluoride in plantation soil are the main sources of absorption by tea plant root via active trans-membrane transport and anion channels. Most fluoride is readily transported through the xylem as F- /F-Al complexes to leaf cell walls and vacuole. The findings indicate that tea plants employ cell wall accumulation, vacuole compartmentalization, and F-Al complexes to co-detoxify fluoride and aluminum, a possible tolerance mechanism through which tea tolerates higher levels of fluoride than most plants. Furthermore, dietary and endogenous factors influence fluoride bioavailability and should be considered when exposure levels of fluoride in commercially available dried tea leaves are interpreted. The relevant current challenges and future perspectives are also discussed. © 2020 Society of Chemical Industry.


Asunto(s)
Camellia sinensis/química , Fluoruros/análisis , Fluoruros/metabolismo , Aluminio/análisis , Aluminio/metabolismo , Disponibilidad Biológica , Transporte Biológico , Camellia sinensis/metabolismo , Pared Celular/química , Pared Celular/metabolismo , Exposición Dietética/efectos adversos , Exposición Dietética/análisis , Humanos , Hojas de la Planta/química , Hojas de la Planta/metabolismo , Medición de Riesgo , Suelo/química , Té/química
11.
Chemosphere ; 262: 128317, 2021 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-33182083

RESUMEN

The development of industrialization and agricultural activities have carried various negative impacts to living organisms in recent decades and also, the frequent problem of inorganic pollution have been environmental anxiety to the community. Among these, Cr6+ and F- are priority poisonous pollutants from many industries. In this work, we present a low-cost synthesis procedure to obtain biocompatible zirconium incorporated chitosan-gelatin composite (CS-Zr-GEL) were fabricated and explored for the adsorptive removal of toxic Cr6+ and F- from water. The adsorption mechanism of toxic Cr6+ and F- was done by batch mode as a function of contact time, solution pH and co-existing ions. The obtained materials were extensively studied by several physico-chemical techniques to access their properties by X-ray diffraction (XRD), scanning electron microscopy with Energy Dispersive X-ray Spectroscopy (SEM-EDX), Fourier-transform infrared spectroscopy (FTIR), Brunauer-Emmett-Teller (BET), thermogravimetric analysis (TGA), and differential scanning calorimetry (DSC) analysis. Additionally, the fabricated adsorbent is highly dependent on solution pH. The kinetic and isotherm data were fitted using pseudo-second-order kinetic and Langmuir isotherm models. The maximum adsorption capacity for CS-Zr-GEL is 138.89 and 12.13 mg/g at 323K for Cr6+ and F- respectively. These findings demonstrate that the CS-Zr-GEL adsorbent represents a promising candidate that would have a practical influence on water/wastewater treatments.


Asunto(s)
Quitosano/química , Cromo/análisis , Fluoruros/análisis , Gelatina/química , Contaminantes Químicos del Agua/análisis , Purificación del Agua/métodos , Circonio/química , Adsorción , Concentración de Iones de Hidrógeno , Cinética , Aguas Residuales/química
12.
Gen Dent ; 69(1): 17-20, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33350950

RESUMEN

The objective of this study was to compare fluoride levels in commercially available black tea, green tea, and matcha tea. Tea samples were purchased from a local supermarket in the United States and prepared according to the manufacturer's directions to mimic consumer activity. The selected products included 3 black teas (Bigelow Earl Grey, Twinings of London Lady Grey, and Lipton), 2 green teas (Bigelow and Lipton), and 3 matcha teas (Mighty Leaf, Celestial Seasonings, and Matcha Love). For all products except Mighty Leaf and Matcha Love, 250 mL of deionized water (DIW) was heated to boiling. One tea bag was added and stirred for 2 minutes. For Mighty Leaf matcha, 300 mL of DIW was used, but the sample was otherwise prepared as previously described. Matcha Love was prepared by stirring 0.5 tsp of green tea powder for 2 minutes in 30 mL of DIW heated to boiling. A 10-mL aliquot was taken from each tea group and from DIW alone (control) and combined with 10 mL of total ionic strength adjustment buffer (TISAB II) before it was measured with a combination fluoride electrode and pH/ion meter. The sample size was 5 separately prepared and independently measured tea servings per group. Fluoride concentrations were calculated from a calibration curve constructed from appropriate fluoride standards and then statistically analyzed using analysis of variance followed by the Student-Newman-Keuls post hoc test (α = 0.05). The DIW control group had negligible fluoride content. All tested tea samples contained fluoride in amounts ranging from 0.521 to 6.082 mg/L. The mean concentration differed significantly among brands and types of tea. Matcha green tea powder had the highest concentration of fluoride. Most teas contain a higher fluoride concentration than optimally fluoridated water (0.7 mg/L). Dental healthcare professionals should consider this information when advising caries prevention regimens for patients and determining the potential for dental or skeletal fluorosis in at-risk patients.


Asunto(s)
Fluoruros , , Fluoruros/análisis , Humanos , Estados Unidos
13.
Environ Pollut ; 270: 116227, 2021 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-33333408

RESUMEN

This meta-analysis systematically evaluated the effects of water improvement and defluoridation on fluorosis-endemic areas in North and South China. The study used PubMed, Embase, China National Knowledge Infrastructure, and Wanfang to retrieve relevant research studies published between January 2000 and October 2019. The data included water fluoride levels, dental fluorosis prevalence in children 8-15 years of age, urinary fluoride levels in children and adults, and skeletal fluorosis prevalence in adults. Fixed-effects and random-effects models were used in the meta-analysis. A total of 17 research articles met the inclusion criteria and had an average water improvement period of 15.8 years. With water improvement, water fluoride levels decreased from 2.72 mg/L to 0.54 mg/L (95% confidence intervals: -2.75, -1.58), which was below the standard for drinking water (1.5 mg/L). Additionally, after water improvement, the prevalence of dental fluorosis decreased from 54.5% to 36.2% (95% confidence intervals: 0.12, 0.31) in children, and the prevalence of skeletal fluorosis decreased from 13.7% to 4.2% (95% confidence intervals: 0.16, 0.40) in adults. Urinary fluoride levels decreased from 3.06 mg/L to 1.70 mg/L (OR = -2.03, 95% confidence intervals: -2.77, -1.30) in children and from 2.29 mg/L to 1.72 mg/L (OR = -0.57, 95% confidence intervals: 0.65, -0.49) in adults. The results showed that the prevalence of dental fluorosis and skeletal fluorosis and urinary fluoride levels were significantly reduced by water improvement. This study findings revealed that the effects of water improvement and defluoridation were greater in South China than in North China, and it is obviously related to the time of water improvement and reducing fluoride.


Asunto(s)
Agua Potable , Fluorosis Dental , Adulto , Niño , China/epidemiología , Fluoruros/análisis , Fluorosis Dental/epidemiología , Humanos , Prevalencia , Agua , Abastecimiento de Agua
14.
Ecotoxicol Environ Saf ; 209: 111826, 2021 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-33360592

RESUMEN

BACKGROUND: Excessive fluoride exposure is related to adverse health outcomes, but whether dopamine (DA) relative genes are involved in the health effect of low-moderate fluoride exposure on children's intelligence remain unclear. OBJECTIVES: We conducted a cross-sectional study to explore the role of DA relative genes in the health effect of low-moderate fluoride exposure in drinking water. METHODS: We recruited 567 resident children, aged 6-11 years old, randomly from endemic and non-endemic fluorosis areas in Tianjin, China. Spot urine samples were tested for urinary fluoride concentration, combined Raven`s test was used for intelligence quotient test. Fasting venous blood were collected to analyze ANKK1 Taq1A (rs1800497), COMT Val158Met (rs4680), DAT1 40 bp VNTR and MAOA uVNTR. Multivariable linear regression models were used to assess associations between fluoride exposure and IQ scores. We applied multiplicative and additive models to appraise single gene-environment interaction. Generalized multifactor dimensionality reduction (GMDR) was used to evaluate high-dimensional interactions of gene-gene and gene-environment. RESULTS: In adjusted model, fluoride exposure was inversely associated with IQ scores (ß = -5.957, 95% CI: -9.712, -2.202). The mean IQ scores of children with high-activity MAOA genotype was significantly lower than IQ scores of those with low-activity (P = 0.006) or female heterozygote (P = 0.016) genotype. We detected effect modification by four DA relative genes (ANKK1, COMT, DAT1 and MAOA) on the association between UF and IQ scores. We also found a high-dimensional gene-environment interaction among UF, ANKK1, COMT and MAOA on the effect of IQ (testing balanced accuracy = 0.5302, CV consistency: 10/10, P = 0.0107). CONCLUSIONS: Our study suggests DA relative genes may modify the association between fluoride and intelligence, and a potential interaction among fluoride exposure and DA relative genes on IQ.


Asunto(s)
Dopamina/genética , Exposición a Riesgos Ambientales/estadística & datos numéricos , Fluoruros/toxicidad , Inteligencia/efectos de los fármacos , Niño , China/epidemiología , Estudios Transversales , Agua Potable , Femenino , Fluoruros/análisis , Genotipo , Humanos , Pruebas de Inteligencia , Masculino , Polimorfismo Genético
15.
Ecotoxicol Environ Saf ; 209: 111732, 2021 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-33373928

RESUMEN

Fluoride, widely presented in drinking water and tea, may be detrimental or beneficial to the human health, depending on its dosages ingested. However, the relationship of different dosages of fluoride and gut microbiota is still unclear. In this work, the fermentation model using fecal samples provided by four volunteers was used to evaluate the effects of different dosages of fluoride (1, 2, 10 and 15 mg/L) on the gut microbiota in vitro. The result showed low dosages of fluoride (1 and 2 mg/L) had limited effect on the structure and functional Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway of gut microbiota. Furthermore, the low dosage of fluoride could promote the growth of beneficial gut microbiota, including Faecalibacterium and Lactobacillus. Whereas, the high dosage of fluoride (10 and 15 mg/L) significantly changed the composition and functional KEGG pathway of gut microbiota. Moreover, the high dosage of fluoride could also reduce the beneficial gut microbiota, including Faecalibacterium and Phascolarctobacterium, and increase the harmful bacterium including Proteobacteria and Enterobacteriaceae. Both low and high dosages of fluoride showed limited effect on the productions of short-chain fatty acids (SCFAs). Thus, the beneficial or detrimental fluoride to gut microbiota depends on its dosages. The fluoride is expected to serve as a food additive in suitable dosage to improve human health through modulation of the gut microbiota. Moreover, more attention should be paid to toxicity of fluoride with high dosage to gut microbiota.


Asunto(s)
Fluoruros/toxicidad , Microbioma Gastrointestinal/efectos de los fármacos , Contaminantes Químicos del Agua/toxicidad , Bacterias/metabolismo , Ácidos Grasos Volátiles/análisis , Ácidos Grasos Volátiles/química , Ácidos Grasos Volátiles/metabolismo , Heces/química , Fermentación , Fluoruros/análisis , Humanos , Lactobacillus/metabolismo
16.
Ecotoxicol Environ Saf ; 207: 111512, 2021 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-33254392

RESUMEN

This study investigated 324 groundwater samples collected from the southwest plain of Shandong Province during the dry and wet seasons. Groundwater fluoride in the study area and the influencing factors were characterized and discussed using statistical analysis, ion ratios, Piper diagrams, the saturation index (SI) and ArcGIS software. In addition, the risk posed by groundwater fluoride to human health was assessed. The results showed that groundwater in the study area had elevated fluoride concentrations, with average dry and wet season concentrations of 1.15 mg·L-1 and 1.08 mg·L-1, respectively. Groundwater fluoride showed consistent spatial variations during the dry and wet seasons, with a significant regionalization pattern of low concentrations in the east and high concentrations in the west. Groundwater F- was significantly negatively correlated with Ca2+ and positively correlated with pH, HCO3- and Na+. Important factors identified as having an effect on groundwater F- in the study area included the balance of dissolution of fluorite and calcite, the weakly alkaline environment and cation exchange. In addition, hydrochemical types of high-fluoride groundwater in the study area were identified as mainly HCO3-Na and SO4·Cl-Na. The assessment of the risk of high groundwater fluoride to human health showed that children are more at risk compared to adults, with the risk during the dry season exceeding that over the wet season. It is recommended that water quality management in the study area prioritize the formulation of measures to mitigate high concentrations of fluoride in groundwater .


Asunto(s)
Monitoreo del Ambiente , Fluoruros/análisis , Contaminantes Químicos del Agua/análisis , Adulto , Carbonato de Calcio/química , Niño , China , Agua Subterránea/química , Salud , Humanos , Minerales/análisis , Sodio/análisis , Calidad del Agua
17.
Georgian Med News ; (306): 57-61, 2020 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-33130647

RESUMEN

The aim of study was to assess prevalence, severity, and associated risk-factors for Dental Fluorosis in Pre-School children (1-6 years) in Fluoride deficient regions (1) Tbilisi (F=0.08-0.22 mg/l) and (2) Akhaltsikhe, (F<0.4 mg/l) Georgia, having different geographic location and socio-economic conditions. A cross-sectional study was carried out on 570 pre-school aged children (1-6 years) attending public kindergartens of Tbilisi and Akhaltsikhe region. Descriptive analysis was performed for Dental Fluorosis prevalence and severity using Thylstrup-Fejerskov Index (TFI). Correlative analysis was done to assess information about possible acquired risk-factors through questionnaire including biological and social variables. To differentiate genuine Dental fluorosis from other non-carious resembling defects ECEL method was introduced. For Fluoride concentration determination in potable water (2) ISO 10359-1:1992 Electrochemical probe as ion-selective electrode method was used. Information about F concentration in Tbilisi tap water (1) was obtained by GWP. (Georgian Water and Power, 2019). The overall Prevalence of Dental Fluorosis in study group was 6.3% (36 Children) (95% CI;(4.3 - 8.3)). There was no statistically significant difference in the level of Dental Fluorosis prevalence between rural and urban residents (P>0.05). Dental Fluorosis prevalence was similar in both gender groups. 6.0% of girls had dental fluorosis (95% CI 2.2% - 8.8%), whereas DF prevalence in boys was 6.5% (95% CI3.7% - 9.3%), respectively. Regular brushing and dentifrices ingestion were not effecting DF prevalence and severity (p>0.05). Indoor coal-burning environment increasing airborne Fluoride absorption during pregnancy was recognized as a risk-factor for dental fluorosis occurrence in children (OR=5.8 (95% CI; 2.1-15.9)). High tea consumption (≥2 cups/day) was increasing Odds of DF occurrence (OR=17.3 (95% CI; 7.4-40.7)). Exposure to diverse fluoride sources like indoor coal-burning and high tea consumption in non-fluoridated areas is a risk-factor of Dental Fluorosis in study community.


Asunto(s)
Fluoruros , Fluorosis Dental , Niño , Preescolar , Estudios Transversales , Femenino , Fluoruros/efectos adversos , Fluoruros/análisis , Fluorosis Dental/epidemiología , Fluorosis Dental/etiología , Georgia (República)/epidemiología , Humanos , Lactante , Masculino , Prevalencia , Factores de Riesgo
18.
Environ Monit Assess ; 192(11): 712, 2020 Oct 18.
Artículo en Inglés | MEDLINE | ID: mdl-33070268

RESUMEN

A major public health concern in Mexico is the natural contamination of groundwater with fluoride and arsenic. Therefore, this work aimed to evaluate the magnitude of human health risk after determining fluoride and arsenic concentrations in groundwater samples (n = 50) from the Metropolitan area of the city of San Luis Potosi, Mexico. Fluoride levels in water were determined via a potentiometric method using an ion-selective electrode. Arsenic concentrations in water samples were determined with an Atomic Absorption technique. Subsequently, a probabilistic health risk assessment was developed (Monte Carlo Analysis). Fluoride levels in water ranged from 0.20 to 3.50 mg/L. For arsenic, the mean level found in the assessed water samples was 15.5 ± 5.50 µg/L (range: 2.50-30.0 µg/L). In addition, when the probabilistic health risk assessment was completed, a mean HI (cumulative hazardous index) of higher than 1 was detected, indicating a high NCR (non-carcinogenic risk) for children and adults. According to the results found in this study, exposure protection campaigns are imperative in the Metropolitan area of the city of San Luis Potosí, Mexico, to successfully diminish exposure to arsenic and fluoride and, as a consequence, decrease the NCR in the population living in that region of Mexico.


Asunto(s)
Arsénico , Agua Potable , Adulto , Arsénico/análisis , Niño , Ciudades , Agua Potable/análisis , Monitoreo del Ambiente , Fluoruros/análisis , Humanos , México , Medición de Riesgo
19.
Sci Total Environ ; 741: 140460, 2020 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-32886997

RESUMEN

Too little and too much fluorine are potentially hazardous for human health. In the Jiaokou Irrigation District, ionic concentrations, hydrogeochemistry, and fluoride contaminations were analyzed using correlation matrices, principal component analysis (PCA), and health risk assessment. The patterns for the average cation and anion concentrations were Na+ > Mg2+ > Ca2+ > K+ and SO42- > HCO3- > Cl- > NO3- > CO32-. The fluoride concentrations ranged between 0.29 and 8.92 mg/L (mean = 2.4 mg/L). 5% of the samples displayed lower than the recommended limit of 0.5 mg/L fluoride content, while 69% exceeded the allowable limits of 1.5 mg/L for drinking. The low F- content is distributed in a small part of the southeast, while elevated F- mainly in the central area of the study region. The PCA results indicated three principal components (PC), PC1 having the greatest variance (45.83%) and affected by positive loadings of TDS, Cl-, SO42-, Na+, and Mg2+, PC2 accounting for 17.03% and dominated by Ca2+, pH, HCO3-, and K+, and PC3 representing 12.17% and mainly comprising of CO32-. High fluoride groundwater is of the SO4-Cl-Na type, followed by HCO3-Na type. Evaporation and ion exchange play important roles in producing high fluoride groundwater. Furthermore, saturation index and anthropogenic activities also promote the high fluoride concentrations. The values of the total hazard quotient of 93% groundwater samples were greater than 1 for infants, followed by 85% for children, 68% for teenagers, and 57% for adults. Non-carcinogenic health risks to infants may occur over the entire study area, while for adults, health risks are mainly found in Weinan and Pucheng. High fluorine may have a potential negative influence on neurodevelopment, especially for infants and children. Adults in this region have serious dental fluorosis and skeletal fluorosis because of long-term drinking of high fluoride groundwater. Therefore, measures, including using organic fertilizers, strengthening defluoridation process, and optimizing water supply strategies, are necessary in this area.


Asunto(s)
Agua Subterránea , Contaminantes Químicos del Agua/análisis , Adolescente , Adulto , Niño , China , Monitoreo del Ambiente , Fluoruros/análisis , Humanos , Medición de Riesgo
20.
Vet Clin North Am Food Anim Pract ; 36(3): 581-620, 2020 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-32948413

RESUMEN

Water is the most important nutrient for rangeland livestock. However, competition with municipalities, industry, and other water users often results in grazing livestock being forced to use water supplies that are less than perfect. Surface water in western rangleands are often contaminated by mineral extraction, irrigation runoff and other human activities. Mineral contaminants in drinking water are additive with similar contaminants in feedstuffs. The goal of this article is to provide producers and veterinarians with the basic background to make informed decisions about whether a given water supply is "safe" for livestock.


Asunto(s)
Enfermedades de los Bovinos/inducido químicamente , Enfermedades de los Bovinos/prevención & control , Metales/análisis , Metales/envenenamiento , Calidad del Agua , Agua/normas , Animales , Arsénico/análisis , Intoxicación por Arsénico/prevención & control , Intoxicación por Arsénico/veterinaria , Bovinos , Intoxicación por Flúor/prevención & control , Intoxicación por Flúor/veterinaria , Fluoruros/análisis , Humanos , Agua/análisis , Abastecimiento de Agua/normas
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