Elnor C. Roa
MSU-Naawan
1- occurs naturally in the environment and exists in a large
number of forms.
- a constituent element of the earth ( like lead or cadmium)
Mercury
2Mercury
-“heavy metal” because it is
very dense. A cup of
mercury, for example,
weighs more than three
kilograms; that’s nearly
fourteen-times heavier
than a cup of water
3
3Mercury Pollution
The Minamata tragedy
™ The hazards of methylmercury poisoning
received international attention in 1956 when
many of the residents of Minamata, Japan,
became seriously ill, or died, after eating the fish
and shellfish in Minamata Bay.
36
The Iraq Hg poisoning incident
-1971
-6,500 people were hospitalized and more
than 400 died after eating wheat grain
treated with a methylmercury fungicide
5Status of Mercury Pollution
‰ One of the biggest mining
operations in the Philippines is
located in Diwalwal, one of the
Barangays in the municipality of
Monkayo, in Compostela Valley.
Mercury pollution in the Philippines
-is mainly due to the presence of small-scale mining.
¾ the most controversial smallscale mining area in the
Philippines due to mercury
pollution.
39
6
¾ highly environmentally sensitive
because of its location.Status of Mercury Pollution
Figure 1 . Map showing the Agusan Marsh area
7
ƒ The creeks around Diwalwal
flow into the Mamunga and
Naboc rivers that in turn drain
into the Agusan River, which is
about 24 kilometers away
from the mining site
ƒ Hence, the impact of mercury
pollution due to mining in
Diwalwal extends far
beyond the site.
ƒ The provinces of Agusan del
Sur and Agusan del Norte that
are crossed by the Agusan River
to Butuan Bay are also
affected. Status of Mercury Pollution
Table 2. Estimated annual mercury consumption in various gold rush
areas in Davao Region
Gold Rush Area Estimated
Number of
Establish-
ments
Estimated
Monthly Hg
Consumption
Estimated
Monthly THg
Consumption
In kilogram
Estimated Total
Annual Mercury
Consumption
in kilogram
Diwalwal 318 1 to 1.5 477* 5,724*
Boringot 60 1 60 720
Biasong 50 1 50 600
Diat 199 1 199 2,388
Panganason 49 1 49 588
Gumayan 30 5.5 165 1,980
Bango 37 2 74 888
Lumanggang, Maco 7 1 7 84
Lumanggang,
Pantukan
21 1 21 252
Inopuan-Saravan 25 1 25 300
GRAND TOTAL 796 13,524
Source of Basic Data: Mines and Geoscience Bureau, Region XI, Davao City cited by Ed. B.
Prantilla & C. Martinez in Heavy Metals Contamination in Davao Region
Note: Asterisk means the figure uses the 1.5 kilograms average monthly consumption.
Estimated Total Annual Mercury Consumption
13,524 kg
9Table 3. Mercury levels (ppm) in fish samples from seven sampling stations,
Davao City, 1982
Status of Mercury Pollution
Station/
Sample
September October November
Fish Hg in ppm Fish Hg in ppm Fish Hg in ppm
Tibungko 1
2
3
Tabangko 0.175 Matambaka 0.027 Matambaka 0.018
Matambaka 0.202 Barilis 0.270 Matambaka 0.026
Tamban 0.147 Matambaka 0.026 Bilung-bilung 0.015
Ilang 1
2
3
Samin-samin 0.186 Manalangsi 0.474 Matambaka 0.201
Moro-moro 0.149 Tulingan 0.504* Biling-bilung 0.142
Dangit 0.371 Barilis 0.941* Bilung-bilung 0.182
COACO 1
2
3
Dangit 0.079 Timbungan 0.0.28 Moro-moro 0.032
Dangit 0.038 Matambaka 0.028 Matambaka 0.098
Dangit 0.023 Tulingan 0.134 Tulingan 0.055
Bucana 1
2
3
Tangigue 0.622* Barilis 0.776* Timbungan 0.449
Maya-maya 0.497 Barilis 0.922* Matambaka 0.224
Barilis 0.560* Barilis 0.936* Bilung-bilung 0.309
Times 1
2
3
Moro-moro 0.249 Matambaka 0.048 Timbungan 0.414
Pirit 0.202 Tulingan 0.064 Moro-moro 0.403
Matambaka 0.121 Matambaka 0.080 Tulingan 0.771*
Godo 1
2
3
Tangigue 0.230 Barilis 0.342 Barilis 0.177
Barilis 0.702* Barilis 0.164 Tulingan 0.154
Barilis 0.819* Barilis 0.294 Barilis 0.228
Guinoo 1
2
3
Buga-ong 0.178 Barilis 0.650* Moro-moro 0.416
Diwit 0.144 Diwit 0.628* Barilis 0.500
Tangigue 0.132 Diwit 0.549* Barilis 0.502*
Source: Rosita Fundador, “Environmental Quality of Coastal Waters of Davao City with Special Reference to Pollution”, Ph.D.
Dissertation, University of the Philippines, August 1984 (Unpublished), Table 17 as cited by Prantilla & Martinez Heavy Metals
Contamination in Davao Region
10Status of Mercury Pollution
Table 4. Mercury levels (ppm) in shellfish samples from seven sampling
stations, Davao City, 1982
Station/
Sample
September October November
Shellfish Hg,ppm Shellfish Hg, ppm Shellfish Hg, ppm
Tibungko 1
2
3
Trachycardium
egmontianum
0.158 Anadara cepoides 0.554* Lingula anatifera 0.074
Polinices sp. 0.122 - do - 3.378* Venus euglypta 0.095
Oliva sp 0.118 Gafrarium tumidium 1.931* Gafrarium tumidium 0.038
Ilang 1
2
3
Gafrarium tumidtum 0.162 Terebralia sp 0.766* Nerita sp 0.141
- do - 0.351 Turbo sp 0.760* Nerita sp 0.114
- do - 0.413 Nerita sp 0.664* Nerita sp 0.254
COACO 1
2
3
Cypreae arabica 0.063 Andara antiquata 0.060 Venus euglypta 0.103
- do - 0.028 - do - 0.107 Gafrarium tumidium 0.058
- do - 0.049 Gafrarium tumidium 0.026 Gafrarium tumidium 0.063
Bucana 1
2
3
Lingula anatifera 0.439 Tivela sp 0.084 Hydrobia sp 0.238
Tivela sp. 0.520* Tivela sp 0.085 Tellina sp 0.241
Tivela sp 0.504* Tivela sp 0.069 Tellina sp 0.142
Times 1
2
3
Venus mercenaria 0.066 Venus mercenaria 0.086 Venus mercenaria 0.046
Tivela sp 0.069 - do - 0.101 - do - 0.145
Venus mercenaria 0.081 - do - 0.120 - do - 0.150
Godo 1
2
3
Haliotis sp. 0.545* Haliotis sp. 0.291 Haliotis sp. 0.097
Haliotis sp. 0.535* Haliotis sp. 0.226 Haliotis sp. 0.175
Haliotis sp. 0.287 Haliotis sp. 0.257 Haliotis sp. 0.096
Guinoo 1
2
3
Nerita sp. 0.153 Terebralia sp 0.254 Tellina virgata 0.071
Tellina virgata 0.263 Terebralia sp 0.408 Tellina virgata 0.061
Anadontia sp. 0.250 Terebralia sp 0.272 Terebralia sp 0.016
Source: Rosita Fundador, “Environmental Quality of Coastal Waters of Davao City with Special Reference to Pollution”, Ph.D.
Dissertation, University of the Philippines, August 1984 (Unpublished), Table 17 as cited by Prantilla & Martinez Heavy Metals
Contamination in Davao Region
11Status of Mercury Pollution
Table 6. Mercury Levels in Human Population
Source:
a
Dr. Nelia C. Maramba (Consultant, Occupational Toxicology Program, DOH and Head, UP NPCIS) and Dr. Cristina S.
Dablo (MOH, Officer in Charge, NCDCS DOH), “Executive Summary on The Health and Toxicological Assessment Activities
Undertaken in Diwalwal and Apokon (Tagum City), Davao del Norte”, 1996
b
based on the presentation of Dr. Annabelle Yumang of DOH XI on the findings of the study conducted by DOH XI to the
Economic Development Committee (EDC) of the Regional Development Council (RDC), Region XI as recorded by the EDC
Secretariat on the levels of mercury contamination in the blood and hair samples of the miners living in Mt. Diwata and the soil
sediments in Mt. Diwata and fish samples from Davao Region[1].
Sample/Site Hg conc., ppb Remarks
Blooda
(114 school children)
0.48-13.68 24/114 – exhibited Hg
blood levels more than
10 ppb
Blooda
urine
a
(70- miners, field personnel &
residents in Diwalwal)
2.25-26.23
0.79-99.23
6/70 – registered Hg
blood levels more than
20 ppb
3/70 – exhibited
elevated Hg urine levels
<50 ppb
bloodb
(75 directly involved in gold
mining, 25 coming diff.
sectors)
3.51-299.99 60% of those who are
directly involved in gold
mining & 12% of those
w/ no direct exposure -
Hg blood levels <
15
ppb
13Status of Mercury Pollution
Table 7 . Mean concentrations and ranges of Hg in rice grains sampled in
the vicinity of the communal irrigation area (metal values are μg/g dry
weight, unless otherwise stated)
Rice grain Mean Range
Polished + cooked 0.015 0.006-0.037
Polished + no t
cooked
0.018 0.008-0.050
Unpolished 0.020 0.001-0.043
Dry weight 0.021 0.009-0.058
Wet weight 0.016 0.008-0.050
Source:Appleton et al. 2006
14
‰ Much lower Hg concentrations (0.05-0.99 mg/kg) within the range expected for
uncontaminated soils, characterize soils on which corn and bananas are cultivated,
largely because these are not irrigated with Hg-contaminated water from the
Naboc River.Status of Mercury Pollution
Venezuelan Miner burning amalgam to
separate gold from
mercury (Photo: UNIDO)
15
-The estimated total weekly MeHg intake for a person living in the Naboc
area related to the weekly consumption:
2.1 kg of rice = 15 ug MeHg
1 kg of fish = 220 ug MeHg
100 g of mussels = 50 mug MeHg
total = 285 ug MeHg
equivalent to 4.75 ug/kg bw for a 60 kg adult
(nearly three times the PTWI of 1.6 ug/kg bw) Status of Mercury Pollution
Sample Suspended
sediments
Bottom
sediment
Surface
sediment
Naboc
River
52-166
ppm
13 - 55
ppm
Agusan
River
above
Naboc
River
Agusan
River near
Butuan
Bay
<0.04-2
ppm
0.1 ppm
Mamunga
River &
Tributaries
5-84
ppm
2-51
ppm
Appleton et al., 2006
Roa, 2001
16
0.04-1.15
ppm
Comparison of Hg levels in sediments collected from upstream & downstream of
Agusan MarshTotal Hg concentration range in selected plants collected in Agusan River
(January 2001).
Cyperus alternifolius
(0.33 - 0.77 ppm THg)
Lumnitzera sp.
(0.16-0.22 ppm THg)
E. Crassipes
(38.32- 236.16 ppm THg)
17Johnius vogleri (dulama)
(0.19 ppm THg) Gobius guirus
(0.24 ppm THg)
Total Hg concentration range in selected fish species collected in Agusan River
(January 2001) & Butuan Bay.
Tuway = 0.056 ppm THg
19
Source: Resource & Ecological Assessment of Butuan Bay
MSU-Naawan
Mercury content of selected fish and aquatic plants in Agusan River & Estuary
Roa, EC, MSU-NaawanStatus of Mercury Pollution
An Initial Geochemical Assessment of
The Agusan Marsh in Mindanao
ƒ Uncorrected draft report, not official
reference
ƒ A project supportred by VSO &
Ecocaritas Association
Surface Sediment Samples (4/2 6)
Lapag Cr
Dinag
k – 1.07 ppm
at Lake – 0.37 ppm
20Status of Mercury Pollution
Gold Ore
Manual Crushing
Amalgamation/Rod milling
Lime + water
Hg
Amalgam separation
Blowtorching
Amalgam
Borax
Sponge Gold
(14-16 Carats)
Tailings
Hg Vapor
Diagram of the Amalgamation Process In Small-Scale Mining
21™ Mercury released to the atmosphere — either directly or
indirectly — may do one of three things
9It may fall out near the point where it is emitted
(local deposition)
9It may also be transported long distances before it is
deposited at some point downwind. If this takes place
within several hundred kilometers
- regional deposition
9Or it could be transported great distances and enters
to the global atmospheric mercury pool.
THE TRANSPORT and DEPOSITION OF MERCURY
22Effects of mercury
¾Mercury and methylmercury - are referred to as nerve toxicants or neurotoxicants
- affect the central nervous system, causing a number of serious disorders.
¾Neurological and behavioral disorders in humans
have been observed following inhalation of
elemental mercury vapor. Specific symptoms
include:
-tremors, emotional lability, insomnia, memory
loss, neuromuscular changes, and headaches.
11
23
¾ In addition, there are effects on the kidney
and thyroid.
¾ High exposures have also resulted in death.Ecological and wildlife effects: Biological conversion, uptake, and build-up of
mercury in food webs
There are three properties of methylmercury that makes it
particularly harmful to humans and other organisms
- it persists,
- and it bioaccumulates or builds up in organisms and up
along the food chain,
- it is toxic to most life forms
18
24Ecological and wildlife effects: Biological conversion, uptake, and build-up of mercury in
food webs
Bioaccumulation
Biomagnification
19
25Ecological and wildlife effects: Biological conversion, uptake,
and build-up of mercury in food webs
21
Bioaccumulation & Biomagnification
261. Natural
sources
2. Current
anthropogenic
releases from the
mobilization of Hg
in raw mat’ls
3. Current
anthropogenic
releases resulting
from Hg used
intentionally in
products &
processes
4. Re-mobilization
of historic
Anthropogenic
Hg
The releases of mercury to the
biosphere can be grouped in four
categories :
27
Ways for Hg Reductio Sources and cycling of mercury n in the Environment
Releases
Mostly beyond
Human control
Reduce consumption
Use alternate raw materials“pollution
prevention”
1. Reducing mercury m g and
consumption of raw materials and
products that generate releases;
2. Substitution of products
and processes containing or
using mercury;
3. Contro ing mercury
releases through end-ofpipe controls
4. Mercury waste
management.
Ways for Hg Reduction in the Environment
31
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