Port Botany Residents Group Information Briefing
onMercury
Presented by: Hg Recoveries Pty. Ltd.
111th December, 2012
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MERCURYThe chemical symbol
for Mercury isHg
Hg: Chemical Forms & Physical Properties• Mercury - most toxic naturally occurring element known
with exception of radio-active substances.• It is the only element that exists as a liquid at normal
temperatures and pressure on earth.• Elemental (liquid) Mercury evaporates easily to
form a gas:At 200C 30% mass evaporates; at 600C >80% mass evaporates.
• Mercury’s unique physical properties and high reactivity causes extreme toxicity in all mammalian life:- by ingesting any chemical form, or from vaccines that contain Hg- from bioaccumulation & consumption of contaminated food/water
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Orica Chlor Alkali Plant• Operated 1944 to 2002• Depending on the operational cell numbers
– between 7 kg and 14 kg mercury per hour evaporating through the roof vents.
• Large amounts of metallic mercury spilled or lost into the soils
• 90+ tonnes minimum per year of anode sludge’s heavily contaminated with mercury dumped somewhere
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Orica Chlor Alkali Plant(CAP)
• Somewhere between 145 tons and 290 tonnes of gaseous mercury emitted
• Somewhere between 5200 tonnes and 10,400 tonnes of mercury contaminated sludge’s
• Unknown but obviously large amount of mercury contaminating the earth under the plant
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Gaseous Mercury• A % of the mercury lost from the CAP would
have gone into the stratosphere under some atmospheric conditions
• A large % would have formed into liquid mercury in the vicinity of the plant or within about 5km of the plant
• This liquid mercury then gets into water ways and soil and is subject to chemical reactions
• Some of the mercury would stay in the soil and over time can be transported as dust and soil into houses and cars. In confined spaces this mercury can be highly dangerous
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Confined Spaces• The U.S EPA Mercury Response guidebook gives
the following action levels for gaseous mercury in the air of confined spaces e.g a house or apartment;
• Level 3 1.0 µg/m3 or less - No action• Level 2 ≥ 1.0 µg/m3 but less than 10.0 µg/m3
schedule relocation ASAP• Level 3 10.0 µg/m3 or greater – Relocate
Immediately• 1.0 µg is 1/1,000,000th of a gram• There are 1000 grams in a Kg and 1000 Kg in a ton
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Resident Risk Issues• The Orica site is mainly exposed earth• A number of areas of waste land, and
portside storage areas• Significant construction and demolition
activity coupled with high truck movements• Significant wind turbulence in the area due
to proximity of the ocean.• Many other toxic materials and wastes on
the Orica site
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Health Risks• PBM – Particle Bound Mercury created
by releases of gaseous and liquid mercury from the CAP can be easily transported by humans into houses, offices, shops and schools.
• THE CAP has lost hundreds of tons of mercury and it only takes 10/1,000,000 of a gram in a cubic meter of air to cause problems in confined areas
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Bioaccumulation• The key issue with mercury is that it bio-
accumulates through the environment.• It is not unusual for fish in lakes, rivers &
streams and the ocean to have 3-6 million times the mercury level of the water & sediments in those sources
• Invertebrates, vertebrates and plants all bio-accumulate mercury
• There has been no detailed study of this issue in Australia – (unlike North America)
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Metallic Mercury• The key action to prevent
mercury bioaccumulation through the food chain is to remove all mercury from the environment
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Health Risks• There is an active recreational fishing
culture in the Port Botany area and the constant exposure of the recreational fish catch to mercury entails a serious health risk to the community but especially women of child bearing age and young children
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Environmental Risks• The mercury in the Port botany area will
be bio-accumulating through the land based food chain as well
• Mercury pollution of soil in gardens will impact the safety of vegetables and fruit grown in the area
• Predatory such a Sea Eagles, Wedge-tailed Eagles, Owls, Hawks, Falcons and Kookaburra’s will be unable to lay viable eggs due to mercury in their food
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Transformation of Mercury in Air, Water, and Sediment6607.sdr
HgO(s) HgO(aq)
Hg+(aq)
O3
SO3-2
Hg2+
(aq)
Cl- OH
-
Hg(OH)2
HgCl2
Hgo Hg(ll)HCl O3 H2O2 Hg
o+2CH3
•HCl O3H2O2
CH3HgOH+CH3
OH•
(CH3)2Hg
HgO(s)
AIR
Hgo Hg(ll)
CH3Hg-DOC
CH3Hg+ (CH3)2Hg
WATER
SEDIMENT
Hgo
Hg(ll) CH3Hg+
(CH3)2Hg
(CH3)2S-Hg
Bacteria
Shellfish
Fish
InorganicComplexes HgS
H2S
hu
Bacteria Microbes
Hyporheic Zone
Hg: Chemical Reactions in Biological and Environmental Systems
1. Hg0 (liquid or vapour) Hg2+
2. 2Hg0 2Hg1+ (Hg22+) Hg0 + Hg2+
3. Hg0 Hg2+ bacteria (CH3)Hg1+ bacteria (CH3)2Hg
4. (CH3)2Hg (CH3)Hg1+ Hg2+ Hg0
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The above reactions are a Scientist’s way of showing how a single form of mercury present in biological systems can be created from, or be converted into, any other mercury form. Biologically, these reactions can occur over and over in the same life form; explaining mercury’s extreme toxicity, and particularly in human beings.(CH3)Hg1+ & (CH3)2Hg – are different forms of Methylmercury; the most toxic of all mercury substances.
Molecular Mimicry of Hg CompoundsProteins form compounds which are crucial for larger protein synthesis, cell function, production & repair and toxin removal
R R R MeHg binds to sulphydryl groups on blood plasma proteins and is actively transported through cell walls bound to L-Cysteine bySH S S the large neutral amino acid carrier. SH Structurally, the Hg: L-Cysteine complex S Hg mimics the amino acid L-Methionine. R In blood Methyl Mercury (Normal process) R S attaches to cysteinyl residues
(Abnormal) on the haemoglobin molecule R and is slowly distributed from blood to the target organ.
R can be Glutathione (C10H17N3O6S); Cysteine (C3H7NO2S); Methionine
(C5H11NO2S)
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Hg Species & Target Organs in HumansHg Primary Target Absorption EliminationSpecies Organs Rate: Half-Time:Hg0
Liq. Skin, Gut L, L1.– 1% ?, XHg0
Vap. Brain, CNS, Epi Cells EH VH 2+Yrs, ≈60daysHg0
Vap. Lungs, Blood EH EH Spont MinsHg2+ Brain, CNS M H 2-10 yrs, ?Hg2+ Kidney, Liver3.VH H days monthsMethylHg Kidney, Liver, Intestine VH H ≈70 Days, ?MethylHg CNS, Brain; Lungs2 EH H ?; Spont.EthylHg Same as for MeHg ?, but >mobility <MeHg, All but Hg0
Liq. Placenta; Fetal BrainCrosses barriers ??; 2-5+ yrs(accumulates preferentially) Fetal Brain Concentrates 6-10,000 times.
1. Hg0Liq. Hg0
Vap.Not fully considered!2. MeHg salts ≈80%Lungs
3. Enterohepatic Circulation4. HgFetal
Brain cf HgOther Fetal Organs. EH = extremely high; VH = very high; M = moderate; L =
low
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A New Look at an Old Problem
‘Maternal Transfer of Hg to the Developing Embryo/Fetus:’ Is There a Safe Level?
(A Peer reviewed scientific paper published in UK Journal of Toxicological & Environmental Chemistry, September, 2012)
Ian A BrownB Sc (Ap Chem), Dip Ap Chem, Dip Ap Sc, Dip Gem FGAATechnical DirectorHg Recoveries Pty. Ltd.Warragul, Victoria. 3820& Associate Prof. David W Austin, PhDSwinburne Autism Bio-Research Initiative and Brain and Psychological Sciences Research CentreSwinburne University of TechnologyHawthorn, Victoria, 3122
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Mercury exposure is ubiquitous in modern society via vaccines, fish/crustacea, dental amalgam, food, water, and the atmosphere.
• Examines primary Hg exposure to pregnant women & secondary exposure experienced by their unborn babies.
• Babies in utero are at risk of higher mercury exposure than adults (on a dose/wt. basis) - through maternal mercury transfer via the placenta- are more vulnerable to toxic effects of mercury.
• Regulatory advisories around maximum ‘safe’ mercury exposures do not presently - account for pregnant women- or secondary exposure that children in utero can experience.
• Study focuses on embryonic and fetal mercury exposures via exposure to the pregnant mother of two common mercury sources:- parenteral vaccines- and dietary fish
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Fetal mercury exposure (µg/kg) as a function of maternal exposure and placental clearance following a single influenza vaccine administration or fish consumption event.
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1 2 4 8 12 16 20 24 28 32 36 380
0
1
10
100
1,000
10,000
100,000
1,000,000
10,000,000
0% Placental Elimination - 150g Fish Portion90% Placental Elimination - 150g Fish Portion99% Placental Elimination - 150g Fish Portion 0% Placental Elimination - Single Flu Injection90% Placental Elimination - Single Flu Injection99% Placental Elimination - Single Flu Injection
Gestation Period (Weeks)
Feta
l Mer
cury
Exp
osur
e (µ
g H
g/kg
)
US EPA RfD: MeHg 0.1µg / kg / day
ASNZ Fish Limit: 1mg Hg / kg
Lethal Dose for an Adult Human: 1g of Hg Salt
Excel glitch -should be 0.1
‘Maternal Transfer of Hg to the Developing Embryo/Fetus:’
Is There a Safe Level?• Current mercury exposure advisories do not account for
(or offer protection of) developing embryos and fetuses.• Data suggests fetal Hg exposure is intolerably high even
under conservative scenarios of maternal exposure and placental transfer.
• Critical perusal of data demonstrates that Hg passing the placenta throughout entire gestation period is orders of magnitude higher than US EPA Standard for MeHg even under the most conservative exposure and placental transfer scenarios.
• There is, therefore, no safe level of maternal transfer of mercury to a developing embryo/fetus.
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Australian Regulatory Limitsfor Mercury.
• Drinking Water (ADWG 2011)- Hg 1 µg/L max.
• Fish & Crustacea (ASNZ 141-2011)- Hg 1 mg/kg (w/w)1, 2. max.
1: Hg in Fish & Crustacea is present wholly (>95%) as Methyl Mercury 2: Hg in statistically sampled commercial fishing lots max. limit is 0.5
mg/kg. 3. 1 µg is 1/1,000,000 of a gram; 1 mg is 1/1000 of a gram
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Port Botany Residents
Can you really afford to continue ignoring
what is ‘hiding in plain sight’?The Hg issue will not go away by itself!It must, therefore, be totally removed
from the environment!As residents, YOU owe this to theHealth & Wellbeing of Our Future
Generations23