ABSTRACT
Arsenic (As), commonly recognized as a toxic metalloid, is widely
distributed in nature,1 and its background concentration in soils
is generally less than 15 mg As kg−1.2 However, the distribution of As can vary depending on the release of naturally occurring
As through activities such as volcanism, hydrothermal activity, and
weathering of parent materials containing As-bearing minerals.
Anthropogenic activities, such as air emissions, soil amendments,
mining operations, and wood preservation, have also led to elevated
As levels.2,3 Chronic exposure to As has caused a wide variety
of adverse health effects including dermatological conditions and
various cancers.4 Recent studies also indicate that As is a potent
endocrine disruptor, potentially relevant to human developmental
problems and disease risk.5,6 Health problems associated with
exposure to As are a global issue, most notably in Southeast Asia. In
Bangladesh alone, it is estimated that more than 57 million people
rely on drinking water that contains As in excess of theWorld Health
Organization (WHO) standard.7
