Human arsenic exposure and risk assessment at the landscape level: a review

Abstract

Groundwater contaminated with arsenic (As), when extensively used for irrigation, causes potentially long term detrimental effects to the landscape. Such contamination can also directly affect human health when irrigated crops are primarily used for human consumption. Therefore, a large number of humans are potentially at risk worldwide due to daily As exposure. Numerous previous studies have been severely limited by small sample sizes which are not reliably extrapolated to large populations or landscapes. Human As exposure and risk assessment are no longer simple assessments limited to a few food samples from a small area. The focus of more recent studies has been to perform risk assessment at the landscape level involving the use of biomarkers to identify and quantify appropriate health problems and large surveys of human dietary patterns, supported by analytical testing of food, to quantify exposure. This approach generates large amounts of data from a wide variety of sources and geographic information system (GIS) techniques have been used widely to integrate the various spatial, demographic, social, field, and laboratory measured datasets. With the current worldwide shift in emphasis from qualitative to quantitative risk assessment, it is likely that future research efforts will be directed towards the integration of GIS, statistics, chemistry, and other dynamic models within a common platform to quantify human health risk at the landscape level. In this paper we review the present and likely future trends of human As exposure and GIS application in risk assessment at the landscape level.

Applications of Remote Sensing, Geographic Information System and Geostatistics in the Study of Arsenic Contamination in Groundwater

“…In GIS, these layers are used singly or are integrated to derive relevant information about the problem at hand. GIS basically acts as a platform to integrate the various spatial, demographic, social, field-based and analytical data (Khan et al 2009). In GIS, real-world objects or fields are stored and represented using projection system so that their shape, size, position and other characteristics remain intact.…”

“…Spatial distribution of a contaminant and its impact on human and physical environment can be better understood using visualization capabilities of GIS (Khan et al 2009). New probabilistic contamination layers can be generated from spatial analysis of different thematic layers (land use, land cover, drainage, vegetation, soil etc.)…”

“…All of them can be intigrated in the GIS platform. GIS has flexibility in dealing with data with different datum and projection (Khan et al 2009). …”

“…Groundwater is the main source of drinking water in these areas/countries, especially in rural areas. Although human beings are affected mostly through drinking of arsenic contaminated water (Smedley and Kinniburgh 2002), the water-soil-plant-human transfer pathway is also very important (Khan et al 2009). …”

Analytical approaches for arsenic determination in air: A critical review

“…The main concern about the determination of arsenic in environmental samples has been habitually related to its presence in groundwater [11,12], drinking water [9,13], biota [14], soils [15] and food [16]. However, air represents also an important route of dispersion, as it allows As to be transported globally [17,18].…”