Overview of Environmental Contamination in Lao PDR

Dr. Kesiny Phomkeona

Department of Chemistry

Faculty of Science

National University of Laos

Department of Chemistry (DOC) was found

along with the establishment of National

University (05-11-1996).

DOC is a department member of Faculty of

Science (FOS).

Chemistry DepartmentEstablishment

Mrs. Sysavad LUANGSISUPHANHead of Chemistry Department

Analytical Chemistry

Environmental

Chemistry

General Chemistry

Inorganic Chemistry

Organic Chemistry

Physical Chemistry

Pesticide Residue and

water Quality

Researches

Chemistry DepartmentAcademic Distribution

Theoretical and practical works are distributed to not only chemistry students but also to other students from other institutes.

Chemistry DepartmentMain Research Facilities

HPLC/UV-Vis or RID and IC/CD

UV-Vis Spectrophotometers

AAS/Hydride Generation for As and Cold for Hg

TOC Analyzer

CO2 Analyzer

DI water production system and electric Balance GC-MS

Chemistry DepartmentPrevious Research activities

Water Quality research

Pesticide Residue Research

Research Activities in Chemistry Department, NUOL

• Pesticide Residues Analysis: Research is focused on contamination of organochlorine pesticides in foods and environmental samples (2005-2012).

• Water Qualities Analysis: Conduct research in water contaminations and water quality test for fresh and wastewater, and drinking water.

General Information• Land area:

236,800 km2

• Stocked forest land >40%

• Population: 6.5 million people (2012)

• Approx. 83% of population live in rural area.

Current Environment Issue in Lao PDR

The environment and natural resources of Lao PDR are being threatened by a number of factors associated with the mining sector, including hazardous chemicals, including heavy metals such as mercury, lead, cadmium, arsenic, chromium, copper, and zinc as well as persistent organic pollutants (POPs) such as dioxins and furans, PCBs, and various pesticides and herbicides.

Current and Future Interested Researches

•Water Quality.

•Pesticide Residue.

•Chemical Contaminants in Food and water.

•Renewable Energy-Biodiesel.

•Air pollution.

Previous Study on Pesticide Residue

• Department of Chemistry have had assistance from International Program in Chemical Science (IPICS)/ISP, Sweden, to set up capacity on pesticide residue analysis including laboratory and methods to be used since 2005.

• The primary focus of the project was qualitative analysis of organochlorine pesticides in samples, including evaluation of extraction methods by recovery tests, to get an idea of which pesticides can be found in the environment.

2008 (Department of Chemistry, NUOL)• The following organochlorine pesticides were found in sediments, water and

aquatic animals samples collected from Vientiane capital.

PesticidesAmount found, ng/g. Lowest-Highest

Dry season Rainy season

α-HCH 0.023 - 19.630 0.023 - 32.194

β-HCH 0.115 - 19.721 0.526 - 146.200

γ-HCH 1.865 - 424.87 10.362 - 274.611

Aldrin 0.584 - 52.164 2.589 - 89.9

Heptachlor-endo-epoxide 6.485 - 104.686 3.458 - 7.349

α-Endosulfan 0.387 - 76.997 4.842 - 75.329

β-Endosulfan 501.319 15.831-203.166

Dieldrin 60 ND

4,4’-DDE 0.218 - 245.441 0.051 - 132.385

4,4’-DDD 7.352 - 201.203 5.347 - 16.042

4,4’-DDT 0.134 - 91.133 1.691 - 128.078

2009 (Department of Chemistry, NUOL)• The following organochlorine pesticides were found in fruits and

vegetable samples collected from local markets in Vientiane capital.

Pesticides Highest amount found, μg/g.

α-HCH 5.99

β-HCH 0.721

γ-HCH 0.04

Aldrin 1.487

Dieldrin 6.107

4,4’-DDE 0.131

2,4’-DDT 14.876

4,4’-DDT 0.417

2012 (Department of Chemistry, NUOL)

Samples 2,4’ DDT (μg.kg-1) 2,4’ DDE (μg.kg-1) 2,4’ DDD (μg.kg-1)

Orange ND ND < LOQ

Mango ND ND < LOQ

Apple ND < LOQ < LOQ

Chinese pear ND ND < LOQ

Morning glory ND < LOQ < LOQ

Chinese cabbage ND < LOQ < LOQ

Chinese lettuce ND < LOQ < LOQ

Yard long bean < LOQ ND < LOQ

Fish(1) ND 0.48 < LOQ

Fish(2) ND < LOQ < LOQ

Fish(3) ND 0.49 0.47

Fish(4) ND < LOQ < LOQ

Previous Studies on Water Contamination by Heavy Metals

• Water Quality Unit of Chemistry Department has conducted researches on water contamination of heavy metals. The studies were done by staff members and together with supporting undergraduate students to undergo their final projects.

Analysis of heavy metals in samples were performed by Atomic Absorption Spectrophotometer (AAS) with suitable technique for each element.

• Hg : AAS with cold vapor generation• As : AAS with hydride generation• Zn, Cd, Fe, and others: AAS with flame

Hg Contamination in Aquatic Samples(2012)

1 2 3 4 MPL0

0.2

0.4

0.6

0.8

1

1.2

1.4

0.035 0.0420.121

1.18

0.001

Sample

Hg

conc

entr

atio

n, p

pm

MPL = Maximum Permissible Level

1 2 3 4 5 MPL0

0.02

0.04

0.06

0.08

0.1

0.12

0.030.02

0.08

0.1

0.03

0.002

Sample

Hg,

con

cent

rati

on, p

pm

Hg Contamination in Water Samples

MPL = Maximum Permissible Level

d1 d2 d3 d4 d50

0.005

0.01

0.015

0.02

0.025

0.01

0.007

0.011

0.02

0.005

Sample

Hg

conc

entr

atio

n, p

pm

Hg Contamination in Sediment Samples

MPL = Maximum Permissible Level

Arsenic Contamination in Ground Water(UNESCO 2011)

• River mouth & along Mekong River

B.Nam

San

B.Bua

khai

B.Dan

Nua

B.Dan

Taii

B.Paks

e(SV)

Paks

e(KM

)

B.Bun

g San

tha

Don

e Khe

o Nua

Don

e Khe

o Taii

0

20

40

60

80

100

120

10

25

100

50 50

100

10

25

100

As, ppb

As

STD = 10 ppb

Arsenic Contamination in Ground Water(ISP 2012)

s1 s2 s3 MPL0

2

4

6

8

10

12

8.025

6.5637.474

10

Sample

As

con

cen

trat

ion

, pp

b

MPL = Maximum Permissible Level

• Environmental samples in Laos are nowadays contaminated by toxic heavy metals (As and Hg) which exceed maximum permissable limit.

• Organophosphorus and Pyrethroid are nowadays widely used in Laos.

• Studies on Organophosphorus and Pyrethroid are not able to do. Due to the limitation of chemicals and equipments and human resourse.

Conclusion

Acknowledgement

Ms. S. Louangsysouphan

Ms. V. Chounlamany

Dr. P. Inthapanya

Mr. V. Phouthavong

Assoc. Prof. Dr. Peter Sundin Mr. Lars Lundmark

IPIC/ISP

Mr. S. Bouta

THANK YOU