Monitoring Ambient Air 2013

ORAL - Arsenic Speciation in Atmospheric Pm2.5 and PM10

Authors: Dr Bin Chen, Dr Matt A Dexter, Dr Warren T Corns (PSA) V Oliveira, J L Gomez-Ariza and D Sanchez Rodas (Huelva Uni)

Air quality is of great concern to human health.  Atmospheric pollution caused by metal in particulate matter has a major impact.  This is particularly true for arsenic due to its high toxicity.  Arsenic is released to the atmosphere by both anthropogenic and natural sources.  Sources include metal smelting, combustion of fuels and the use of pesticides, with volcanic activity as the main natural source.  Airborne particles are typically classified according to their size distribution.  Studies have typically focussed between the total mercury concentration in total suspended particulate (TSP) and particles of a particular size, e.g. PM2.5sub and PM10.

Arsenic speciation is of particular interest as its toxicity varies with both oxidation state and molecular structure.  Inorganic arsenic species such as arsenite – As(III) – and arsenate – As(V) – are more toxic than methylated species such as monomethylarsonate (MMA) and dimethylarsinate (DMA).  Inorganic arsenic(III) is more toxic than arsenic(V) by both ingestion and inhalation.

An extraction procedure has been developed and optimised to extract arsenic species from air filters.  Arsenic speciation was then determined by high performance liquid chromatography-hydride generation-atomic fluorescence spectrometry (HPLC-HG-AFS).
Data are present from monthly air monitoring at an industrialised urban site in Huelva, Spain, showing seasonal variation in both total arsenic concentration and speciation.

To request a copy of this oral presentation click here.

Written by Dr Warren T Corns:

Organized by the AAMG (Automation and Analytical Management Group) a special interest group of the RSC (Royal Society of Chemistry) - Monitoring Ambient Air 2013.

Dr Warren T Corns and Ralph Cochrane attended the RSC Air Quality AAMG Conference in London on the 10th and 11th December 2013. The meeting had almost 200 delegates from 10 different countries. One of the hot topics of the meeting was the health effects of small particles (PM 2.5 and PM10). These very small particles are emitted into the atmosphere by combustion sources and abrasion. They are so small that when inhaled they remain in the lungs. It is estimated that a 10µg/m3 increase of an ambient annual average level of PM 2.5 is associated with a 6% increase in death rates.Our presentation took this issue one step further. We have developed a method in association with Huelva University in Spain for determining  Arsenic Speciation in PM 2.5 and PM10. To understand the health effects of PM it is essential to understand the composition of the fine particles that we breath. In this study we found that the PM consisted of approx. 0.3% Arsenic. The Arsenic was present predominantly as As(V) which is less toxic than As(III). Arsenic however is known to cause cancer so establishing the composition of PM is of high importance. The study was done in the city of Huelva which is an industrial area with a copper smelter and petrochemical plant. You may request a copy of the presentation by filling out our Information Request. page.