Mobility and bioaccessibility of arsenic (As) bound to titanium dioxide (TiO) water treatment residuals (WTRs).

This work systematically describes arsenic mobility and potential bioaccessibility of arsenic-enriched titanium dioxide water treatment residuals (TiO WTRs) by employing a suite of wet chemical experiments and spectroscopic measurements. Specifically, Environmental Protection Agency (EPA) digestion method 3051a indicated <3% of total arsenic in the solid phase was released, and arsenic assessed by EPA method 1340 for bioaccessibility was below detection limits. A novel finding is while the arsenic appeared to be stable under highly acidic digestion conditions, it is in fact highly mobile when exposed to simple phosphate solutions.

Heavy metal and trace metal analysis in soil by sequential extraction: a review of procedures.

Quantification of heavy and trace metal contamination in soil can be arduous, requiring the use of lengthy and intricate extraction procedures which may or may not give reliable results. Of the many procedures in publication, some are designed to operate within specific parameters while others are designed for more broad application. Most procedures have been modified since their inception which creates ambiguity as to which procedure is most acceptable in a given situation.