Fluoride contamination in groundwater and associated health risks in Karbi Anglong District, Assam, Northeast India.

Health hazards due to excess intake of fluoride via groundwater contamination are a major concern worldwide. This study provides a comprehensive report on the human health risks associated with the consumption of groundwater contaminated by fluoride. Several groundwater samples were collected across 8 blocks of Karbi Anglong district of Assam, India. The concentration of fluoride was observed in the range of 0.15-17.13 mg/L. In 4 out of 8 studied blocks, the mean fluoride level exceeded the permissible limit (1.5 mg/L) as prescribed by the World Health Organization. Elevated fluoride levels in some parts of the district may be attributed mainly to dissolution from fluoride-containing minerals in the granitic rocks and regional geological settings. The health risk of fluoride was assessed in terms of hazard quotient (HQ). The HQ was observed in the ranges of 0.06-10.7 (adult) and 0.2-35 (children). Mean HQ values exceeded the safe level (HQ > 1) for children in all blocks, except B-6 and B-8. For adult population, the HQ value was above the safe limits in 13-40% of the sampled locations in different blocks and HQ values were within safe limits in B-6 and B-8. These findings suggest that some sites in the district need serious attention in order to ensure the health safety of local residents.

Multivariate analysis and health risk assessment of heavy metal contents in foodstuffs of Durban, South Africa.

This study presented a comprehensive analysis of heavy metal contents in foodstuffs and the associated health risk for the residential population in Durban, South Africa. The concentrations of elements in fruits and vegetables, respectively, were (in mg kg-1 dry weight) Cu, 0.52-1.47 and 0.27-2.25; Zn, 0.30-3.05 and 0.56-6.24, Fe, 1.70-22.60 and 0.73-44.90; Mn, 0.37-28.50 and 0.67-13.70; Cr, 0.47-1.47 and 0.37-3.06; Ni 0.03-1.14 and 0.11-2.5;, and Pb, 1.52-3.45 and 1.57-4.52. Multivariate analysis revealed that pineapple in fruits and turnip and carrot in vegetables contained remarkable components of trace metals. The target hazard quotient (THQ) values for heavy metals were arranged in the order of Pb > Mn > Cu > Ni > Zn > Cr. No potential health risks were reported for individual elements over a lifetime of exposure, except children's exposure to Mn in pineapple and Pb in banana, orange small, guava, grape green, grape red, yellow-orange, and kiwifruit. The total THQ due to the dietary intake of multiple metals demonstrated unsafe limits in banana, pineapple, orange small, guava, grape green, grape red, yellow-orange, kiwifruit, and spinach leaf for children and pineapple for adults.

Evaluation of ecological risk of metal contamination in river Gomti, India: a biomonitoring approach.

The aim of this study was to evaluate the extent of heavy metal pollution in river Gomti and associated ecological risk. River water, sediments and locally abundant mollusk (Viviparus (V.) bengalensis) were sampled from six different sites and analyzed for seven metals: Cadmium (Cd), Chromium (Cr), Copper (Cu), Manganese (Mn), Nickel (Ni), Lead (Pb) and Zinc (Zn). Mean metal concentrations (mg/l) in river water were 0.024 for Cd, 0.063 for Cr, 0.022 for Cr, 0.029 for Mn, 0.044 for Ni, 0.018 for Pb and 0.067 for Zn. In river sediments, the concentrations (mg/kg dry wt) were 5.0 for Cd, 16.2 for Cr, 23.2 for Cr, 203.2 for Mn, 23.9 for Ni, 46.2 for Pb and 76.3 for Zn, while in V. bengalensis mean metal concentrations (mg/kg, dry wt) were 0.57 for Cd, 12.0 for Cr, 30.7 for Cu, 29.9 for Mn, 8.8 for Ni, 3.6 for Pb and 48.3 for Zn. Results indicated elevated concentrations of Cu, Zn and Mn in V. bengalensis as compared to other non-essential elements. Potential ecological risk (RI) in sediments showed high to very high metal contamination. Cluster analysis indicated that Pb, Zn, Cd and Ni in sediments may have anthropogenic sources. The findings thus suggest heavy metal contamination of river water and sediments have reached alarming levels, which is well corroborated by elevated level of metal accumulation in V. bengalensis.

Heavy metals assessment in urban soil around industrial clusters in Ghaziabad, India: probabilistic health risk approach.

Metal contamination in the urban soil in the industrial city of Ghaziabad district was investigated. Spatial distribution of Cu, Cr, Pb, Cd, Zn, Mn, Fe and Ni in the urban soil was produced. The mean Cu, Cr, Pb, Cd, Zn, Mn, Fe and Ni contents in the urban topsoil samples (122, 288, 147, 0.4, 187, 386, 21,433 and 147mg/kg, respectively) were compared with the mean concentrations for other cities around the world. Cu, Cr, Pb, Zn and Ni concentrations appears to be higher than many other cities in the world. Non-cancer risk (Hazard Index) and cancer risk of children and adults due to exposure to the urban soil were estimated using 95th percentile values of total metal concentrations. Cluster analysis classified the sampling sites into three groups. Group 1 sites near commercial, industrial or dumpsite showed relatively higher concentrations of metals as compared to group 2 and 3 that were basically commercial or residential sites. It clearly indicates significant effects of rapid urbanization and industrialization in the last few decades in Ghaziabad. Correlation analysis and principal component analysis indicated common industrial source for Cu, Pb and Zn for group 1 sites. Cr may have point anthropogenic source. Except for Zn and Ni in group 2 sites, other metals may have come from natural sources while in group 3, all metals may have lithogenic source. Combined (ingestion, dermal and inhalation) hazard index (HI) values for children exceeded the safe level (HI=1) for Cr (2.21) and Pb (0.67) close to 1. Cancer risk due to Cr, Pb, Cd and Ni were within acceptable range (1E-06 to 1E-04).

Heavy metals contamination in sediments of Bharalu river, Guwahati, Assam, India: A tributary of river Brahmaputra.

This study aimed to assess heavy metals in the surface sediments of the Bharalu river, India. Metal concentrations ranged from 6.65-54.6 mg/kg for Ni, 25.2-250.0 mg/kg for Zn, 83.3-139.1 mg/kg for Pb, and 11940.0-31250.0 mg/kg for Fe. The level of metal contamination was assessed using sediment quality guidelines, geo-accumulation index (Igeo), enrichment factor (EF), pollution Load Index (PLI),Nemerow's pollution index (PIN), and potential ecological risk index. Pb exceeded the sediment quality guidelines at all sites indicating a potential threat to the river ecosystem. (Igeo) and EF also showed moderate to severe enrichment for Pb. Potential ecological risk (RI) showed low risk in the sediments, and Pb is the major contributor to ecological risk. Overall, pollution indices revealed comparably higher contamination of the sediments in the downstream sites than in the upstream site. PCA and correlation matrix analysis indicated both anthropogenic and natural origins for metals. Among anthropogenic sources, urban discharges and waste dumping could be mainly attributed to metal contamination in the river sediments. These findings may aid in developing future river management methods explicitly aimed at tackling heavy metal pollution to prevent further damage to the river ecosystem.

Metal contamination in market based vegetables in an industrial region, India.

Concentrations of metals were determined in market vegetables in Ghaziabad industrial region. The average concentrations of metals (mg/kg dry wt.) in vegetables ranged from 0.57 to 9.77, 0.72 to 22.17, 2.76 to 46.63, 2.53 to 5.53, 28.87 to 65.94, 6.77 to 74.1, 8.43 to 161.1, 23.46 to 36.55 and 4.74 to 24.18 for Cu, Cr, Pb, Cd, Zn, Mn, Fe, Ni and Co, respectively. Pb, Cd and Ni were above the recommended limit in all the examined vegetables.

Heavy metal contamination in the complete stretch of Yamuna river: A fuzzy logic approach for comprehensive health risk assessment.

River Yamuna is one of the most sacred major tributaries of river Ganga. This study aimed to assess the level of heavy metals in monsoon and non-monsoon season in river Yamuna in Uttar Pradesh, India and to assess the possible source of contamination and its associated health risk. Except for iron (Fe), the mean levels of all metals were within drinking water safe limits in both seasons. Except for chromium (Cr), lower values were observed for other metals in the monsoon season could be attributed dilution effect. Multivariate analysis indicated that both geogenic and anthropogenic sources contribute to heavy metals in river Yamuna in monsoon and non-monsoon seasons. The health risk in terms of hazard index (HI) and fuzzy-logic hazard index (FHI) demonstrated that both HI and FHI values among children exceeded the safe limit in most of the sites in non-monsoon seasons and in few in monsoon season. For adults, HI and FHI values were within safe limit.

Heavy metal(loid)s contamination and health risk assessment of soil-rice system in rural and peri-urban areas of lower brahmaputra valley, northeast India.

The soil-rice system in rural and peri-urban areas of the lower Brahmaputra valley, northeast India was investigated for heavy metal(loid)s using Nemerow's pollution index (PIN) and potential ecological risk index (RI). Potential health risk due to rice consumption grown in the region was assessed in terms of carcinogenic and non-carcinogenic risks. Around 95% of the soil showed acidic nature that ranged from weakly acidic to strongly acidic soil. In terms of PIN, 27.3% of the sampling sites were heavily polluted (PIN≥3), 34.8% moderately, and 37.9% were slightly polluted. The Pb concentration was comparably higher in 57.1% of the rice grain samples and the mean As level (0.17 mg kg-1) was close to the WHO limit. The non-carcinogenic risk in terms of hazard quotient (HQ) was high primarily due to As (HQ > 1), whereas other metals had limited contribution (HQ < 1). The carcinogenic risk based on total cancer risk (TCR) values for adults and children ranged between 0.0039 - 0.019 and 0.0043-0.0211, respectively, exceeding the maximum acceptable level of 1 × 10-4. Among the rice varieties, for non-carcinogenic risks, the maximum hazard index (HI) was noticed for Bahadur and the minimum for Ranjit. Whereas for carcinogenic risks, the maximum TCR was observed for Mahsuri and the minimum for Moynagiri.

Water quality assessment of river Hindon at Ghaziabad, India: impact of industrial and urban wastewater.

River Hindon is a major source of water to the highly populated and predominantly rural population of western Uttar Pradesh, India. The main goal of the present study was to assess the impact of urban and industrial activities on the water quality of river Hindon at the Ghaziabad. For this, river water samples were collected from six different sites all along the route of Hindon main streamline and its branch and were analyzed for pH, turbidity, electrical conductivity (EC), total dissolved solids (TDS), total alkalinity (TA), total hardness (TH) and calcium hardness (Ca-H), chemical oxygen (COD) demand, biochemical oxygen demand (BOD), dissolved oxygen (D.O.), sulphate (as SO(4)(2-)), nitrate (as NO(3)(-)) and chloride (Cl-) levels. There were drastic variations for EC (0.83-5.04 ms), turbidity (28.7-109.3 NTU), TDS (222.2-2426.3 mg l(-1)), SO(4) (36.4-162.4 mg l(-1)), NO(3) (106-245 mg l(-1)), TA (347.0-596.3 mg l(-1)), TH (235.1-459.9 mg l(-1)), Ca-H (64.5-402.2 mg l(-1)), BOD (27-51 mg l(-1)) and COD (85.0-337.4 mg l(-1)) levels at different sites. Water pollution indicating parameters were manifold higher than the prescribed limit by the National Pollution Control Agency, i.e. CPCB. This is the first study on itself and the interrelationship of human activities and river water quality makes the study significant and interesting to assess the pollution load discharges in catchments of Hindon at Ghaziabad. Overall, the water quality of Hindon was relatively poor with respect to its use for domestic purposes.

Groundwater quality in Ghaziabad district, Uttar Pradesh, India: Multivariate and health risk assessment.

This study aimed to assess the quality of groundwater and potential health risk due to ingestion of heavy metals in the peri-urban and urban-industrial clusters of Ghaziabad district, Uttar Pradesh, India. Furthermore, the study aimed to evaluate heavy metals sources and their pollution level using multivariate analysis and fuzzy comprehensive assessment (FCA), respectively. Multivariate analysis using principle component analysis (PCA) showed mixed origin for Pb, Cd, Zn, Fe, and Ni, natural source for Cu and Mn and anthropogenic source for Cr. Among all the metals, Pb, Cd, Fe and Ni were above the safe limits of Bureau of Indian Standards (BIS) and World Health Organization (WHO) except Ni. Health risk in terms of hazard quotient (HQ) showed that the HQ values for children were higher than the safe level (HQ = 1) for Pb (2.4) and Cd (2.1) in pre-monsoon while in post-monsoon the value exceeded only for Pb (HQ = 1.23). The health risks of heavy metals for the adults were well within safe limits. The finding of this study indicates potential health risks to the children due to chronic exposure to contaminated groundwater in the region. Based on FCA, groundwater pollution could be categorized as quite high in the peri-urban region, and absolutely high in the urban region of Ghaziabad district. This study showed that different approaches are required for the integrated assessment of the groundwater pollution, and provides a scientific basis for the strategic future planning and comprehensive management.

Assessment of heavy metal contamination in Hindon River sediments: a chemometric and geochemical approach.

The aim of this study was to assess the level of heavy metals (Cd, Cr, Cu, Fe, Mn, Ni, Pb, and Zn) in the surface sediments of the Hindon River, India that receives both treated and untreated municipal and industrial discharges generated in and around Ghaziabad, India. Mean metals concentrations (mg kg(-1)) were in the range of; Cu: 21.70-280.33, Cd: 0.29-6.29, Fe: 4151.75-17318.75, Zn: 22.22.50-288.29, Ni: 13.90-57.66, Mn: 49.55-516.97, Cr: 17.48-33.70 and Pb: 27.56-313.57 respectively. Chemometric analysis was applied to identify contribution sources by heavy metals while geochemical approaches (enrichment factor and geo-accumulation index) were exploited for the assessment of the enrichment and contamination level of heavy metals in the river sediments. Chemometric analysis suggested anthropic origin of Cu, Cd, Pb, Zn, and Ni while Fe showed lithogenic origin. Mn and Cr was associated and controlled by mixed origin. Geochemical approach confirms the anthropogenic influence of heavy metal pollution in the river sediments. The study suggests that a complementary approach that integrates chemometric analysis, sediment quality criteria, and geochemical investigation should be considered in order to provide a more accurate appraisal of the heavy metal pollution in river sediments. Consequently, it may serve to undertake and design effective strategies and remedial measures to prevent further deterioration of the river ecosystem in future.

Assessment of metals in water and sediments of Hindon River, India: impact of industrial and urban discharges.

The aim of this study was to assess the level of heavy metals (Cd, Cr, Cu, Fe, Mn, Zn and Pb) in water and sediments of Hindon River in industrialized city Ghaziabad, India. A total of 6 stations, covering the upstream and downstream sites of Hindon, were selected for this study. Metal concentration (mgkg(-1)) ranged: Cd, 1.15-3.47; Cu, 9.42-195.1; Cr, 42.9-250.4; Fe, 221.2-237.9; Mn, 61.0-201.7; Zn, 3.98-85.0; and Pb, 5.07-59.1 in river sediments. The enrichment factor (%) for sediment ranged from 0.05 to 99.8% at point and non-point polluted stations of Hindon. The geoaccumulation index (I(geo)) suggested "unpolluted to moderate pollution" of Mn, Pb and Zn (I(geo)<1), "moderate pollution" of Cu, Cr, Fe (I(geo)<2), and "very strong pollution" of Cd (I(geo)>5) in River Hindon at Ghaziabad city. The industrial and urban discharges in river catchment areas were the major sources of heavy metals in river.