Partitioning of 232Th, 230Th and 228Th in the surface water of northwest peninsular Malaysia coastal waters as tracer for SPM sources

Nor Faizah M.M.K. Noorulhudha, Che Abd. Rahim Mohamed

Research output: Contribution to journalArticle

Abstract

Natural thorium radioisotopes (232Th, 230Th, 228Th, 234Th) are well known to be particle reactive, thus they are often used to study the geochemical process of particle reactive matter. In this study, water samples were collected from Langkawi Island and Pangkor Island from six and ten sampling stations respectively, to determine the activity of 232Th, 230Th and 228Th in dissolved (DISS) and suspended particulate matter (SPM) phases, and estimate the sources and origin of SPM into the marine environment. The results in terms of volume activity concentration (mBq/L) shows that the activity level of 228ThDISS was higher than 228ThSPM at all sampling stations possibly due to the behaviour of the 228Th parent, 228Ra which is easily desorbed from SPM. At several stations far from the coast; stations L4 (4.58km), P7 (3.16 km), P6 (2.1 km), P10 (1.38 km), the activity of 232ThDISS was higher compared to 232ThSPM. These stations behave the same way as the open ocean in which 232ThDISS is contributed by atmospheric dust. Indeed, the partition of thorium between dissolved and SPM phase can be used to detect anthropogenic organic pollution as in station L6 in which thorium activity in dissolved phase is higher compared to in SPM phase. Moreover, the use of the (232Th/230Th)SPM ratio is useful to detect lithogenic input to the marine environment in which the ratio ranges from 0.13 to 0.5 and 0.7 to 3.16 for stations that are far and near to the coast respectively, except for station P1. However the data analysis shows that there is no clear pattern of kd values at both sampling sites, probably due to the adsorption and desorption processes of 232Th and 230Th that occurs in the water column. Nevertheless, as the SPM concentration (mg/L) increases, the kd value decreases except for the activity of 228Th which shows a strong negative correlation with SPM.

Original languageEnglish
Pages (from-to)43-52
Number of pages10
JournalEnvironmentAsia
Volume10
Issue number2
DOIs
Publication statusPublished - 1 Jul 2017

Fingerprint

Particulate Matter
Malaysia
suspended particulate matter
Surface waters
coastal water
partitioning
tracer
surface water
Water
Thorium
thorium
Sampling
Islands
Coastal zones
marine environment
sampling
station
coast
Dust
open ocean

Keywords

  • Coastal water
  • Distribution coefficient
  • Thorium

ASJC Scopus subject areas

  • Toxicology
  • Environmental Science(all)

Cite this

Partitioning of 232Th, 230Th and 228Th in the surface water of northwest peninsular Malaysia coastal waters as tracer for SPM sources. / Noorulhudha, Nor Faizah M.M.K.; Mohamed, Che Abd. Rahim.

In: EnvironmentAsia, Vol. 10, No. 2, 01.07.2017, p. 43-52.

Research output: Contribution to journalArticle

@article{1d2efbb20f0f43cd97cfd0854ece1e80,
title = "Partitioning of 232Th, 230Th and 228Th in the surface water of northwest peninsular Malaysia coastal waters as tracer for SPM sources",
abstract = "Natural thorium radioisotopes (232Th, 230Th, 228Th, 234Th) are well known to be particle reactive, thus they are often used to study the geochemical process of particle reactive matter. In this study, water samples were collected from Langkawi Island and Pangkor Island from six and ten sampling stations respectively, to determine the activity of 232Th, 230Th and 228Th in dissolved (DISS) and suspended particulate matter (SPM) phases, and estimate the sources and origin of SPM into the marine environment. The results in terms of volume activity concentration (mBq/L) shows that the activity level of 228ThDISS was higher than 228ThSPM at all sampling stations possibly due to the behaviour of the 228Th parent, 228Ra which is easily desorbed from SPM. At several stations far from the coast; stations L4 (4.58km), P7 (3.16 km), P6 (2.1 km), P10 (1.38 km), the activity of 232ThDISS was higher compared to 232ThSPM. These stations behave the same way as the open ocean in which 232ThDISS is contributed by atmospheric dust. Indeed, the partition of thorium between dissolved and SPM phase can be used to detect anthropogenic organic pollution as in station L6 in which thorium activity in dissolved phase is higher compared to in SPM phase. Moreover, the use of the (232Th/230Th)SPM ratio is useful to detect lithogenic input to the marine environment in which the ratio ranges from 0.13 to 0.5 and 0.7 to 3.16 for stations that are far and near to the coast respectively, except for station P1. However the data analysis shows that there is no clear pattern of kd values at both sampling sites, probably due to the adsorption and desorption processes of 232Th and 230Th that occurs in the water column. Nevertheless, as the SPM concentration (mg/L) increases, the kd value decreases except for the activity of 228Th which shows a strong negative correlation with SPM.",
keywords = "Coastal water, Distribution coefficient, Thorium",
author = "Noorulhudha, {Nor Faizah M.M.K.} and Mohamed, {Che Abd. Rahim}",
year = "2017",
month = "7",
day = "1",
doi = "10.14456/ea.2017.20",
language = "English",
volume = "10",
pages = "43--52",
journal = "EnvironmentAsia",
issn = "1906-1714",
publisher = "Thai Society of Higher Eduation Institutes on Environment",
number = "2",

}

TY - JOUR

T1 - Partitioning of 232Th, 230Th and 228Th in the surface water of northwest peninsular Malaysia coastal waters as tracer for SPM sources

AU - Noorulhudha, Nor Faizah M.M.K.

AU - Mohamed, Che Abd. Rahim

PY - 2017/7/1

Y1 - 2017/7/1

N2 - Natural thorium radioisotopes (232Th, 230Th, 228Th, 234Th) are well known to be particle reactive, thus they are often used to study the geochemical process of particle reactive matter. In this study, water samples were collected from Langkawi Island and Pangkor Island from six and ten sampling stations respectively, to determine the activity of 232Th, 230Th and 228Th in dissolved (DISS) and suspended particulate matter (SPM) phases, and estimate the sources and origin of SPM into the marine environment. The results in terms of volume activity concentration (mBq/L) shows that the activity level of 228ThDISS was higher than 228ThSPM at all sampling stations possibly due to the behaviour of the 228Th parent, 228Ra which is easily desorbed from SPM. At several stations far from the coast; stations L4 (4.58km), P7 (3.16 km), P6 (2.1 km), P10 (1.38 km), the activity of 232ThDISS was higher compared to 232ThSPM. These stations behave the same way as the open ocean in which 232ThDISS is contributed by atmospheric dust. Indeed, the partition of thorium between dissolved and SPM phase can be used to detect anthropogenic organic pollution as in station L6 in which thorium activity in dissolved phase is higher compared to in SPM phase. Moreover, the use of the (232Th/230Th)SPM ratio is useful to detect lithogenic input to the marine environment in which the ratio ranges from 0.13 to 0.5 and 0.7 to 3.16 for stations that are far and near to the coast respectively, except for station P1. However the data analysis shows that there is no clear pattern of kd values at both sampling sites, probably due to the adsorption and desorption processes of 232Th and 230Th that occurs in the water column. Nevertheless, as the SPM concentration (mg/L) increases, the kd value decreases except for the activity of 228Th which shows a strong negative correlation with SPM.

AB - Natural thorium radioisotopes (232Th, 230Th, 228Th, 234Th) are well known to be particle reactive, thus they are often used to study the geochemical process of particle reactive matter. In this study, water samples were collected from Langkawi Island and Pangkor Island from six and ten sampling stations respectively, to determine the activity of 232Th, 230Th and 228Th in dissolved (DISS) and suspended particulate matter (SPM) phases, and estimate the sources and origin of SPM into the marine environment. The results in terms of volume activity concentration (mBq/L) shows that the activity level of 228ThDISS was higher than 228ThSPM at all sampling stations possibly due to the behaviour of the 228Th parent, 228Ra which is easily desorbed from SPM. At several stations far from the coast; stations L4 (4.58km), P7 (3.16 km), P6 (2.1 km), P10 (1.38 km), the activity of 232ThDISS was higher compared to 232ThSPM. These stations behave the same way as the open ocean in which 232ThDISS is contributed by atmospheric dust. Indeed, the partition of thorium between dissolved and SPM phase can be used to detect anthropogenic organic pollution as in station L6 in which thorium activity in dissolved phase is higher compared to in SPM phase. Moreover, the use of the (232Th/230Th)SPM ratio is useful to detect lithogenic input to the marine environment in which the ratio ranges from 0.13 to 0.5 and 0.7 to 3.16 for stations that are far and near to the coast respectively, except for station P1. However the data analysis shows that there is no clear pattern of kd values at both sampling sites, probably due to the adsorption and desorption processes of 232Th and 230Th that occurs in the water column. Nevertheless, as the SPM concentration (mg/L) increases, the kd value decreases except for the activity of 228Th which shows a strong negative correlation with SPM.

KW - Coastal water

KW - Distribution coefficient

KW - Thorium

UR - http://www.scopus.com/inward/record.url?scp=85024475860&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=85024475860&partnerID=8YFLogxK

U2 - 10.14456/ea.2017.20

DO - 10.14456/ea.2017.20

M3 - Article

AN - SCOPUS:85024475860

VL - 10

SP - 43

EP - 52

JO - EnvironmentAsia

JF - EnvironmentAsia

SN - 1906-1714

IS - 2

ER -