Mercury pollution in the aquatic

environment of Suriname

Paul Ouboter

National Zoological Collection(NZCS)/

Environmental Research Center (CMO)

Anton de Kom University of Suriname

Small-scale gold mining

in Suriname

• First gold rush 1880-1910

• Present gold rush 1980-present

• 25,000 to 35,000 gold miners (est. GMD

2000)

• Production 10,000-20,000 kg gold/year (est.

Veiga, 1997)

• Many gold miners are mining illegally

• Most miners are Maroons and Brazilians

• Mining concentrated in Greenstone Belt

Small-scale gold mining

in Suriname

• Small-scale operations have recently

changed into medium-scale operations

• Mercury used for amalgamation, usually in

combination with sluice boxes or dredges

• Usually no tailing ponds used

• Mercury lost to environment 10,000-

20,000 kg (est Veiga, 1997)

• 55% of mercury lost to atmosphere, 45%

to streams

Method used in smaller streams

Environmental impacts

• Deforestation

• Destruction of hydrology

• Increase of insolation due to deforestation

• Increase of turbidity, metals and nutrients in stream

• Change in aquatic vegetation

• Change in fish community

• Mercury pollution

• Mercury accumulation in food chain

Mercury is

neurotoxic

Mercury remains in ecosystems for ages

Regular consumption of fish with elevated levels poses health

risk

Piscivorous wildlife impacted

Mercury bio-accumulates

Mercury is volatile

Mercury levels globally rising

Fish and wildlife in remote areas have

elevated levels

Mercury is

neurotoxic

Mercury bound to

fine sediments

What is the problem with mercury?

MERCURY RESEARCH IN

SURINAME

Mercury research other organizations/authors

• OAS project on introduction of retorts (incl. some

measurements) (Pollack, de Kom, Quik & Zuilen, 1998)

• Mercury levels in gold-miners (de Kom, van der Voet &

de Wolff, 1998)

• Mercury in communities at the Lawa River (Cordier,

Grasmick, Paquier-Passelaigue, Mandereau, Weber &

Jouan, 1998)

• Mercury in fish (Mol, Ramlal, Lietar & Verloo, 2001)

• Mercury in gold-mining sites (Arets, v.d. Meer, v.d. Brink,

Tjon, Atmopawiro & Ouboter, 2006)

Mercury research other organizations/authors

(cont.)

• Mercury in pregnant women and new-borns (Mohan,

Tiller, van der Voet & Kanhai, 2005)

• Mercury in communities in the interior (Peplow &

Augustine, 2007)

• Mercury in the coastal and urban atmosphere (Müller,

Wip, Warneke, Holmes, Dastoor & Notholt, 2012)

• Mercury in communities (Min. public health; to start?)

Projects NZCS/CMO • Mercury pollution in the Commewijne River

(Quik & Ouboter, 2000; WWF-Guianas)

• Mercury pollution in the gold mining areas

(Ouboter, Landburg, White, Mol, v.d. Lugt &

Quik, 2007; WWF-Guianas)

• Atmospheric transportation of mercury (Ouboter,

Mol & Quik, 2003; Schure-Beijerinck-Popping

Fund)

• Mercury source in the Fallawatra Formation

(Landburg, 2005; NZCS/CMO)

Projects NZCS/CMO (cont.)

• Mercury poisoning of Brownsweg villagers (Ouboter &

Landburg, 2010; WWF-Guianas)

• Mercury levels in Western Suriname (NZCS/CMO)

• Environmental and community levels of mercury in

Kwakoegron and Pikin Saron (e.g. Hawkins, Lichtveld &

Ouboter, 2011; Tulane University)

• Mercury levels in sediment cores of floodplain rivers

(NZCS/CMO)

• Mercury levels in mud flats before the coast of Suriname

(NZCS/CMO & Tulane University)

Publication incl. most of these projects: Ouboter, Landburg,

Quik, Mol & v.d. Lugt, 2012

Methods • Data based on 9 different projects carried out between 1998-

2013, including 60 localities: – 14 localities in Greenstone Belt

– 18 localities downstream Greenstone Belt

– 7 control localities upstream of gold mining

– 17 localities in central and western Suriname

– 4 localities at the coast of Suriname

• 5 communities, 3 in Greenstone Belt, 1 downstream of Greenstone Belt and 1 upstream of Greenstone Belt for fish consumption study and mercury in hair

• Measurement of water quality in the field (pH, conductivity, dissolved oxygen, temperature, turbidity)

• Sampling of water, sediment and fish tissue according to sampling protocol

• Fish caught using gill nets or bought from local fishermen

• Samples transported to laboratory on ice

• Mercury analyzed with mercury analyzer using cold-vapor atomic absorption

• Quality check for all analytic sessions

Hoplias aimara (anjoemara)

Serrasalmus rhombeus (piranha) Piranha (Serrasalmus rhombeus)

Why investigate mercury in aquatic

ecosystems ?

• Air and water are transportation

mechanisms; provide one-moment in time

data

• Terrestrial soil data spatially very variable

• Mercury bound to sediment in aquatic

environment

• Mercury bio-accumulated in fish

Mercury in water

Mercury in bottom sediment

Mercury in predatory fish

Serrasalmus rhombeus

0

0.5

1

1.5

2

2.5

3

3.5

0 5 10 15 20 25 30 35 40 45

Standard length (cm)

Hg

(m

g/k

g)

Gold mining areas

Brokopondo Reservoir

Piki Pada

Upstream gold mining

Western Suriname

Hoplias aimara

0

0.2

0.4

0.6

0.8

1

1.2

1.4

1.6

0 10 20 30 40 50 60 70 80 90

Standard length (cm)

Hg

(m

g/k

g)

Gold mining areas

Upstream gold mining

Western Suriname

WHAT IS THE SOURCE OF

THE MERCURY

Natural mercury emission sources

• Geologic weathering

• Volcanism

• Evaporation from waters

• Plant transpiration and decomposition

Anthropogenic mercury emission

sources

• Producers of mercury and its compounds

• Consumers of mercury and its compounds

• Burning of fossil fuels

• Pyrometallurgical processes

• Forest fires

Estimated annual anthropogenic Hg

emissions ( in 103 kg Hg yr-1)

Gold

mining

Biomass

burning

Industry

Brazil 1. Lacerda & Marins,

1997

2. Meech et al., 1995

77.91

70 - 1702

8.71

88 - 1042

28.91

Suriname 1. Mol et al., 2001

2. UNEP, 2008

201 0.31 0.15-0.62

Where does the mercury come

from in Suriname??

• Gold mining ?

• Naturally in base rock, sediment and soil ?

Roulet et al.(1998): “… the natural burden of the soils is much

more important than potential new inputs of anthropic Hg from

goldmining or biomass burning, representing more than 97%

of the Hg accumulated in soils. Consequently, the deposition

and incorporation of anthropic Hg is negligible and soils could

be considered as a major reservoir of natural Hg”.

Mercury in core samples from

floodplains

Mercury in core samples from floodplains

0 0.05 0.1 0.15 0.2 0.25 0.3 0.35 0.4

Saramacca1

Saramacca2

Saramacca3

Saramacca4

Coppename1

Coppename2

Coppename3

Coppename4

Nickerie1

Nickerie2

Nickerie3 0-5

5-10

10-15

15-20

20-25

25-30

30-35

35-40

40-45

45-50

Results show:

• Relatively high mercury levels in

undisturbed Western Suriname

• No correlation between mercury levels and

distance from Greenstone Belt

• No mercury source in Fallawatra formation

• Mercury in core samples indicate an

anthropogenic origin

• Mercury in floodplain of Coppename River

(undisturbed) on average higher than in

Saramacca River (gold mining)

WHY HIGH MERCURY LEVELS

IN UNDISTURBED AREAS?

Mercury evaporated

and transpirated

in gold mining areas

Mercury vapor

transported to SW by NE

tradewind

Wet and dry depositing of mercury in central and

SW Suriname

Mechanism 1:

• Most depositing occurs in areas with high

precipitation (windward side of mountain

ranges)

In polluted rivers much

of the mercury is

bound to the high load of suspended sediments

Mercury-sediment

complex will not easily

pass biological

membranes

Mercury is less

biological available

In pristine rivers the load of

suspended sediments is

less

Mercury is more

biological available

Higher mercury

levels in biota

Mechanism 2:

Predicted mercury levels

IMPACT ON PUBLIC HEALTH

Pikin Saron

Kwakugron

Brownsweg

Njun Jacobkondre

Pusugrunu

Mercury in hair

0

2

4

6

8

10

12

14

HG

(U

G/G

)

Women

Men

Adults

Children (5-12 y)

Fish consumption surveys Brownsweg

Conclusions on mercury levels in

aquatic ecosystems in Suriname

• Levels in predatory fish often above norm for human consumption in most of Suriname

• Levels in bottom sediments often high

• Highest levels in Brokopondo Reservoir

• Increased levels in human population

• Also high levels in shallow sea and “pristine” areas in Central and Western Suriname

• Small-scale gold mining is the main cause of increased mercury levels, also in pristine areas

• Pristine areas are polluted by atmospheric transportation of mercury, precipitation and biological availability.

Impacts of mercury on local

communities

• Drinking water usually below norm

(suspended sediments biggest problem)

• Predatory fish often above norm for

human consumption

• Mercury may remain in system for long

time

• Mercury may interfere with public health

and, in worst case scenario also with

development of communities in interior

WHAT CAN WE DO ABOUT

THE PROBLEM?

Phase 1:

• Additional research

• Increase awareness of population, esp.

local communities

• Advocate restricted consumption of large

predatory fish

Phase 2:

• Regulate and control gold mining

operations

• Train gold miners in methods without

mercury (and other environmental

measures)

• Prohibit the import and use of mercury

Phase 3:

• Rehabilitate mined-out areas

Present and future research on

mercury levels:

• Extension of human related projects to other

communities in the interior

• Investigate correlation between mercury in fish

and humans and water chemistry (turbidity, pH

and DOC)

• Investigate mercury levels in mud flats at the

coast

Acknowledgements

• All persons assisting in the field and laboratory

Financial support:

• WWF-Guianas

• Schure-Beijerinck-Popping Fund

• Tulane University

• Tropenbos

• Stinasu

Thank you!