| 1. |
- Bhowmick, S., et al.
(författare)
-
Arsenic mobilization in the aquifers of three physiographic settings of West Bengal, India : Understanding geogenic and anthropogenic influences
- 2013
-
Ingår i: Journal of Hazardous Materials. - : Elsevier BV. - 0304-3894 .- 1873-3336. ; 262, s. 915-923
-
Tidskriftsartikel (refereegranskat)abstract
- A comparative hydrogeochemical study was carried out in West Bengal, India covering three physiographic regions, Debagram and Chakdaha located in the Bhagirathi-Hooghly alluvial plain and Baruipur in the delta front, to demonstrate the control of geogenic and anthropogenic influences on groundwater arsenic (As) mobilization. Groundwater samples (n=90) from tube wells were analyzed for different physico-chemical parameters. The low redox potential (Eh=-185 to -86mV) and dominant As(III) and Fe(II) concentrations are indicative of anoxic nature of the aquifer. The shallow (<100m) and deeper (>100m) aquifers of Bhagirathi-Hooghly alluvial plains as well as shallow aquifers of delta front are characterized by Ca2+HCO3 - type water, whereas Na+ and Cl- enrichment is found in the deeper aquifer of delta front. The equilibrium of groundwater with respect to carbonate minerals and their precipitation/dissolution seems to be controlling the overall groundwater chemistry. The low SO4 2- and high DOC, PO4 3- and HCO3 - concentrations in groundwater signify ongoing microbial mediated redox processes favoring As mobilization in the aquifer. The As release is influenced by both geogenic (i.e. geomorphology) and anthropogenic (i.e. unsewered sanitation) processes. Multiple geochemical processes, e.g., Fe-oxyhydroxides reduction and carbonate dissolution, are responsible for high As occurrence in groundwaters.
|
|
| 2. |
- Nriagu, J. O., et al.
(författare)
-
Arsenic in soil and groundwater : an overview
- 2007. - 9
-
Ingår i: Arsenic in Soil and Groundwater Environment. - Amsterdam, The Netherlands : Elsevier. - 9780444518200 ; , s. 3-60
-
Bokkapitel (övrigt vetenskapligt/konstnärligt)abstract
- Contamination of the environment with arsenic (As) from both anthropogenic and natural sources has occurred in many parts of the world and is recognized as a global problem. Principal anthropogenic sources of As include base metal smelters, gold mines, power plants that burn As-rich coals or treated lumber, disposal sites for wastes from As-processing plants, as well as industrial and municipal dump sites. In many areas, the levels of As in the environment have become one of concern and epidemiological studies have documented various adverse health effects on local populations. Arsenic poisoning episodes from exposure to industrial sources have been reported all over the world; for instance, in Japan, where cases have been associated with pollution around As mines and pollution of groundwater around As-using industries and industrial waste burial sites. Other examples of contaminated environments with increased risk for As poisoning include agricultural lands treated with arsenical pesticides, urban areas, war zones defoliated or sprayed with As compounds, and the superfund sites in the United States and other countries. Although a lot of people get exposed, most often, however, it is not possible to associate the exposure to elevated As levels with adverse human health effects. Nevertheless, long-term cumulative exposure to As in these contaminated environments should be a matter of public health concern and scientific interest.
|
|
| 3. |
- Bhowmick, S., et al.
(författare)
-
Saliva as a biomarker of arsenic exposure
- 2014
-
Ingår i: One Century of the Discovery of Arsenicosis in Latin America (1914-2014). - : CRC Press. - 9781138001411 ; , s. 540-542
-
Konferensbidrag (refereegranskat)abstract
- Saliva is a biofluid that has not been used extensively as a biomonitoring tool in epidemiological studies. This study presents the arsenic (As) concentrations in saliva samples collected from populations of West Bengal, India. We found a significant (p < 0.05) association between the Log transformed Daily Ingestion of As (μg day-1) and the As concentration in saliva (r = 0.68). Additionally, As concentration of saliva and urine also had a significant positive correlation (r = 0.60, p < 0.05). Male participants, smokers and cases of skin lesion were independently and significantly associated with increase in salivary As. Thus our findings show that saliva is a useful biomarker of As exposure in the study population.
|
|
| 4. |
- Halder, Dipti, et al.
(författare)
-
Arsenic exposure and health risk from consumption of brown rice in rural Bengal, India
- 2012
-
Ingår i: Understanding the Geological and Medical Interface of Arsenic, As 2012 - 4th International Congress: Arsenic in the Environment. - : Taylor & Francis Group. - 9780415637633 ; , s. 505-507
-
Konferensbidrag (refereegranskat)abstract
- This study investigates the Arsenic (As) concentration in different types of brown rice grain and assesses As exposure and non-cancer health risk from rice consumption. Daily Intake (DI rice) and Hazard Quotient (HQ) from rice were calculated for the people who are consuming these type of rice. Daily intake value of As from rice was compared with previous WHO recommended Provisional Tolerable Daily Intake value (PTDI) of 2.1 ÎŒg/day/kg bw to understand which kind of rice may pose potential health risk. Hazard quotient (HQ) was determined to understand the potential non-cancer health risk of the people who are consuming these rice. This study indicates that for SB brown rice consumer in 29% cases DI rice exceeds the previous PTDI value and 100% cases HQ value exceeds 1.
|
|
| 5. |
- Halder, Dipti, et al.
(författare)
-
Risk of arsenic exposure from drinking water and dietary components : Implications for risk management in rural Bengal
- 2013
-
Ingår i: Environmental Science and Technology. - : American Chemical Society (ACS). - 0013-936X .- 1520-5851. ; 47:2, s. 1120-1127
-
Tidskriftsartikel (refereegranskat)abstract
- This study investigates the risk of arsenic (As) exposure to the communities in rural Bengal, even when they have been supplied with As safe drinking water. The estimates of exposure via dietary and drinking water routes show that, when people are consuming water with an As concentration of less than 10 μg L-1, the total daily intake of inorganic As (TDI-iAs) exceeds the previous provisional tolerable daily intake (PTDI) value of 2.1 μg day-1 kg-1 BW, recommended by the World Health Organization (WHO) in 35% of the cases due to consumption of rice. When the level of As concentration in drinking water is above 10 μg L-1, the TDI-iAs exceeds the previous PTDI for all the participants. These results imply that, when rice consumption is a significant contributor to the TDI-iAs, supplying water with an As concentration at the current national drinking water standard for India and Bangladesh would place many people above the safety threshold of PTDI. We also found that the consumption of vegetables in rural Bengal does not pose a significant health threat to the population independently. This study suggests that any effort to mitigate the As exposure of the villagers in Bengal must consider the risk of As exposure from rice consumption together with drinking water.
|
|
