I  U  P  A  C

 

 

 

News & Notices

Organizations & People

Standing Committees

Divisions

Projects

Reports

Publications
. . CI
. . PAC
. . Macro. Symp.

. . Books
. . Solubility Data

Symposia

AMP

Links of Interest

Search the Site

Home Page

 

Pure Appl. Chem. 74(10), 1843-1850, 2002

Pure and Applied Chemistry

Vol. 74, Issue 10

Arsenic. An environmental problem limited by solubility*

M.Clara F.Magalh�es

Department of Chemistry, University of Aveiro, P-3810-193 Aveiro, Portugal

Abstract: Arsenic is a toxic element for animals and the majority of plants, in spite of evidence that it is also an essential element. The long-term intake of small doses of arsenic has a carcinogenic effect. There are well-identified regions where arsenic ground water concen- trations can reach values higher than 2 mg/L. Water purification and waste treatment techniques based on (1) precipitation of calcium, magnesium, and iron(III) arsenates, and/or (2) adsorption or coprecipitation of arsenic oxyanions are unlikely to produce aqueous solutions with arsenic concentrations below the guideline values proposed for arsenic dissolved in potable water and treated sewage effluents. As(III) species are more toxic than As(V) species. Arsenate species are predominant at moderate and high redox potentials, while arsenite species occur under more reducing conditions. Metal arsenites are much more soluble than the corresponding metal arsenates, and arsenites are adsorbed less by solid phases. Remediation techniques must consider the available information on solubility and adsorptive properties of As(III) and As(V). The less-soluble lead and barium arsenates are not suitable for arsenic decontamination. New remediation methods must consider solubility data for arsenic-containing materials and minerals.

> erratum

* Lectures presented at the 10th International Symposium on Solubility Phenomena, Varna, Bulgaria, 22 -26 July 2002. Other lectures are published in this issue, pp. 1785-1920.


Page last modified 27 February 2003.
Copyright ©2002-2003 International Union of Pure and Applied Chemistry.
Questions or comments about IUPAC, please contact, the Secretariat.
Questions regarding the website, please contact web manager.