Speciation and total determination of arsenic, chromium and selenium in freshwater bodies sediment

Arsenic (As) is generally known for its toxicity while chromium (Cr) and selenium (Se) at the appropriate amount are essential elements to man and becomes quite toxic in excessive amount. Anthropogenic activities such as industrialization, agricultural and urbanization have led to the contamination...

Full description

Saved in:

Bibliographic Details
Main Author:	Abdullah Salim, Nazaratul Ashifa
Format:	Thesis
Language:	English
Published:	2009
Subjects:	QD Chemistry
Online Access:	http://eprints.utm.my/id/eprint/11105/6/NazaratulAshifaAbdullahMFS2009.pdf
Tags:	Add Tag No Tags, Be the first to tag this record!

id	my-utm-ep.11105
record_format	uketd_dc
spelling	my-utm-ep.111052017-09-14T03:44:44Z Speciation and total determination of arsenic, chromium and selenium in freshwater bodies sediment 2009-11 Abdullah Salim, Nazaratul Ashifa QD Chemistry Arsenic (As) is generally known for its toxicity while chromium (Cr) and selenium (Se) at the appropriate amount are essential elements to man and becomes quite toxic in excessive amount. Anthropogenic activities such as industrialization, agricultural and urbanization have led to the contamination of toxic elements into aquatic that finally end up in the sediment system. Environmental process such as diagenetic process causes the toxic elements to migrate from the bedrock materials into the sediment surface and lastly into the water column. This process has been recognized to be the factor of As contamination in well water in several countries such as Bangladesh, Taiwan, USA and Canada. A number of samples of freshwater sediments from identified rivers and lakes in Johor Bharu area had been analyzed to determine the concentration level of As, Cr and Se using neutron activation analysis (NAA) technique. Certified reference material (CRM) namely IAEA Soil-7, Marine Sediment Reference Material BCSS-1 and PACS -2 were applied to provide good quality assurance control during analysis. The results obtained show that the concentrations of As in the rivers and lakes sediment fall between 10 to 34 ^g g"1 and 18 to 62 ^g g"1, respectively. The concentrations of Cr in the rivers ranged between 27 ^g g"1 to 125 ^g g"1, while in the lake sediments the concentrations ranged between 173 ^g g"1 to 301 ^.g g"1. The river sediment showed the Se concentration ranged between 0.56 ^g g"1 to 1.91 ^g g"1 and in lake sediment the concentration ranged between 0.31 ^g g"1 to 1.08 ^g g"1. The results of the As, Cr and Se concentrations were then compared to the ‘background value’ proposed by National Oceanic and Atmospheric Administration (NOAA), USA and several sediment quality guidelines. The As, Cr and Se concentrations were also correlated and normalized to iron content in order to evaluate and estimate the degree of contaminant enrichment in sediments. For speciation study, the inorganic species of As(III), As(V), Se(IV) and Se(VI) were studied by extracting the sediments using the microwave at the optimized time and power setting in the mild concentration of acid media. The As(III) and As(V) were preconcentrated and separated by ammonium pyrolidinedithiocarbamate (APDTC) into methyl isobuthyl ketone (MIBK) while the Se(IV) and Se(VI) were separated after co"precipitation of sodium dibenzyldithiocarbamate (Na"DBDTC) with phenolphthalein. The efficiencies of all extraction procedures were determined using standard solutions and several CRM. The results showed that As(V) and Se(VI) were the dominant species in the river and lake sediments. 2009-11 Thesis http://eprints.utm.my/id/eprint/11105/ http://eprints.utm.my/id/eprint/11105/6/NazaratulAshifaAbdullahMFS2009.pdf application/pdf en public masters Universiti Teknologi Malaysia, Faculty of Science Faculty of Science
institution	Universiti Teknologi Malaysia
collection	UTM Institutional Repository
language	English
topic	QD Chemistry
spellingShingle	QD Chemistry Abdullah Salim, Nazaratul Ashifa Speciation and total determination of arsenic, chromium and selenium in freshwater bodies sediment
description	Arsenic (As) is generally known for its toxicity while chromium (Cr) and selenium (Se) at the appropriate amount are essential elements to man and becomes quite toxic in excessive amount. Anthropogenic activities such as industrialization, agricultural and urbanization have led to the contamination of toxic elements into aquatic that finally end up in the sediment system. Environmental process such as diagenetic process causes the toxic elements to migrate from the bedrock materials into the sediment surface and lastly into the water column. This process has been recognized to be the factor of As contamination in well water in several countries such as Bangladesh, Taiwan, USA and Canada. A number of samples of freshwater sediments from identified rivers and lakes in Johor Bharu area had been analyzed to determine the concentration level of As, Cr and Se using neutron activation analysis (NAA) technique. Certified reference material (CRM) namely IAEA Soil-7, Marine Sediment Reference Material BCSS-1 and PACS -2 were applied to provide good quality assurance control during analysis. The results obtained show that the concentrations of As in the rivers and lakes sediment fall between 10 to 34 ^g g"1 and 18 to 62 ^g g"1, respectively. The concentrations of Cr in the rivers ranged between 27 ^g g"1 to 125 ^g g"1, while in the lake sediments the concentrations ranged between 173 ^g g"1 to 301 ^.g g"1. The river sediment showed the Se concentration ranged between 0.56 ^g g"1 to 1.91 ^g g"1 and in lake sediment the concentration ranged between 0.31 ^g g"1 to 1.08 ^g g"1. The results of the As, Cr and Se concentrations were then compared to the ‘background value’ proposed by National Oceanic and Atmospheric Administration (NOAA), USA and several sediment quality guidelines. The As, Cr and Se concentrations were also correlated and normalized to iron content in order to evaluate and estimate the degree of contaminant enrichment in sediments. For speciation study, the inorganic species of As(III), As(V), Se(IV) and Se(VI) were studied by extracting the sediments using the microwave at the optimized time and power setting in the mild concentration of acid media. The As(III) and As(V) were preconcentrated and separated by ammonium pyrolidinedithiocarbamate (APDTC) into methyl isobuthyl ketone (MIBK) while the Se(IV) and Se(VI) were separated after co"precipitation of sodium dibenzyldithiocarbamate (Na"DBDTC) with phenolphthalein. The efficiencies of all extraction procedures were determined using standard solutions and several CRM. The results showed that As(V) and Se(VI) were the dominant species in the river and lake sediments.
format	Thesis
qualification_level	Master's degree
author	Abdullah Salim, Nazaratul Ashifa
author_facet	Abdullah Salim, Nazaratul Ashifa
author_sort	Abdullah Salim, Nazaratul Ashifa
title	Speciation and total determination of arsenic, chromium and selenium in freshwater bodies sediment
title_short	Speciation and total determination of arsenic, chromium and selenium in freshwater bodies sediment
title_full	Speciation and total determination of arsenic, chromium and selenium in freshwater bodies sediment
title_fullStr	Speciation and total determination of arsenic, chromium and selenium in freshwater bodies sediment
title_full_unstemmed	Speciation and total determination of arsenic, chromium and selenium in freshwater bodies sediment
title_sort	speciation and total determination of arsenic, chromium and selenium in freshwater bodies sediment
granting_institution	Universiti Teknologi Malaysia, Faculty of Science
granting_department	Faculty of Science
publishDate	2009
url	http://eprints.utm.my/id/eprint/11105/6/NazaratulAshifaAbdullahMFS2009.pdf
_version_	1747814811882749952

Speciation and total determination of arsenic, chromium and selenium in freshwater bodies sediment

Similar Items