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Blake International Blake International LimitedLimited
Conventional Ammunition, Conventional Ammunition,
Alternative MaterialsAlternative Materials
& Risk& Risk
Lead AmmunitionLead AmmunitionLead’s density, malleability and casting characteristics make it an ideal material for use in the mass manufacture of projectiles and it has been used for this application since at least the time of the ancient Greeks.
Today, lead still remains the primary material of choice for bullet and shot manufacture.
0
5
10
15
20
25
0 5 10 15 20
Pb-SbPb
Bi
Cu
Cu-SnSn
Zn
Cu -Poly
Steel
W
W-Poly
W-SnW-Steel (TNI)W-Bronze
Rel
ativ
e C
ost
Density
Projectile Materials
The Alternatives to Lead-Antimony Alloys
COST vs PERFORMANCE
Pb-Zn
Lead is DurableLead is DurableEly Cathedral:
The central tower collapsed in the reign of Henry IV. It was replaced by a hexagonal lantern tower, constructed of oak clad with lead 1322 ~1342.
Lead is DurableLead is DurableRoman Baths at Bath, Somerset.:
Built on a pre-roman pagan site, the Roman baths were constructed 100-300AD.
The lead plumbing is still in place and in working condition after over 1,700 years!
Original plumbing
Development of Lead-Antimony AlloysDevelopment of Lead-Antimony Alloys
© Copyright 2004 Cylenchar Limited© Copyright 2004 Cylenchar Limited
► Corrosion; electrolytic processes / Corrosion; electrolytic processes / redox effects.redox effects.
► Batteries are controlled redox Batteries are controlled redox corrosion systems.corrosion systems.
► Faure invention 1881 Faure invention 1881 improved improved reliability of the redox corrosion reliability of the redox corrosion process through; ‘process through; ‘initiationinitiation’ (Pb0 / ’ (Pb0 / PbOPbO22 / PbSO / PbSO44) and improved ) and improved
‘‘electron yieldelectron yield’ of the plate (Pb-Sb ’ of the plate (Pb-Sb alloy) alloy) Automotive Battery Automotive Battery
► Downside Downside increased corrosion on increased corrosion on +ve Plate. (ANODIC CORROSION)+ve Plate. (ANODIC CORROSION)
Construction of Lead-Acid BatteriesConstruction of Lead-Acid Batteries►Connecting stems and posts - 4% Sb.Connecting stems and posts - 4% Sb.►Negative Plates - 2% Sb Lead alloy.Negative Plates - 2% Sb Lead alloy.►Positive Plates have 0% Sb or low Sb + other Positive Plates have 0% Sb or low Sb + other
metals; Ca, Se, As, Ag, Al, Sn, etc.metals; Ca, Se, As, Ag, Al, Sn, etc.►Recycled Battery Lead contains ~2% Sb. For Recycled Battery Lead contains ~2% Sb. For
positive plate production positive plate production of limited use as it’s of limited use as it’s too corrosivetoo corrosive
►~1.4 M tonne p.a. surplus Pb-Sb alloy ~1.4 M tonne p.a. surplus Pb-Sb alloy ►World wide ~300,000 tonnes p.a. Pb-Sb alloy World wide ~300,000 tonnes p.a. Pb-Sb alloy
used in projectile manufacture.used in projectile manufacture.
Comparative Corrosion of 2mm Pure Lead Shot Comparative Corrosion of 2mm Pure Lead Shot vs US No.8 Lead- (1.25%w/w)Antimony Shotvs US No.8 Lead- (1.25%w/w)Antimony Shot
© Copyright 2004 Cylenchar Limited© Copyright 2004 Cylenchar Limited
No.8 Lead-Antimony Shot and Pure Lead shot (2mm), Corrosion in Acid Rain vs Time
-10
-5
0
5
10
15
20
0 20 40 60 80 100
Days Leaching
Pb
mg/
L
Pb-1.25%Sb Alloy y=0.228x-5.29 Pb 99.999%w/w y=0.0129x+0.382
Roman Lead Sling ShotRoman Lead Sling Shot
Excavated from Roman sites on the Danube. May date from ~100BC, and are no older than Trajan’s Dacian campaign ~100AD. Slow corroding Pb-4%As alloy.
UK-No7.5 Shot; 4% Sb, >1%O UK-No7.5 Shot; 4% Sb, >1%O Polished un-etched cross-sections Polished un-etched cross-sections
© Copyright 2004 Cylenchar Limited© Copyright 2004 Cylenchar Limited
US-#8 Shot ~1.25% Sb, 2.2%OUS-#8 Shot ~1.25% Sb, 2.2%O
Polished un-etched cross-Polished un-etched cross-sectionssections
© Copyright 2004 Cylenchar Limited© Copyright 2004 Cylenchar Limited
The Contents and Structure of The Contents and Structure of ‘Commercial’ Lead Shot‘Commercial’ Lead Shot
► Lead-antimony alloy shot isn’t homogeneous, it’s a Lead-antimony alloy shot isn’t homogeneous, it’s a heterogeneous material, made up of:-heterogeneous material, made up of:-
► Lead-antimony poor alloy granules separated by lead-Lead-antimony poor alloy granules separated by lead-antimony rich (>10%Sb) brittle, ‘porous’ dendritic antimony rich (>10%Sb) brittle, ‘porous’ dendritic eutectic alloy. eutectic alloy. (Pb-As / Pb-Sn alloys have lower redox (Pb-As / Pb-Sn alloys have lower redox potential, with coarser and tighter crystal structure)potential, with coarser and tighter crystal structure)
► High levels of antimony at the surface.High levels of antimony at the surface.► Other metals, (As, Ag, Al, Cu, Sn, Zn) in dendritic Other metals, (As, Ag, Al, Cu, Sn, Zn) in dendritic
zone.zone.► Contains ~6-12%w/w lead oxide and sulphate, from Contains ~6-12%w/w lead oxide and sulphate, from
secondary lead secondary lead (result of crudely melted old batteries!)(result of crudely melted old batteries!)
Summary of Corrosion Rates for Shot
SampleLinearSlope
mg/Litre/day
Approx. Corrosion
Ratemg/m2/day
RelativeCorrosion
Rate
Pure Lead(~2mm dia)
0.0129 0.486 0.045 / 1.00
No8 Lead-Antimony Shot
0.228 10.868 1.00 / 22.4
No 6 Steel Shot 5.52 224.4 20.6 / 462.5
No8 Lead-Antimony Shot +
Steel Shot1.430 68.163 6.27 / 140.3
No8 Lead-Antimony Shot +
1% IFS0.00018 0.0086 0.0008 / 0.018
No.8 Lead-Antimony Shot and No.6 Steel ShotSoluble Metals in Diluted Corrosion Product
0
0.05
0.1
0.15
0.2
0 10 20
x Dilution
Disso
lved
mg/
L
Pb Sb
© Copyright 2004 Cylenchar Limited© Copyright 2004 Cylenchar Limited
Heavy Metals Released on Dilution of Heavy Metals Released on Dilution of Steel Shot Corrosion ProductSteel Shot Corrosion Product
Electrochemical Series of Selected Ammunition Metals and their Contaminants - Thermodynamic issues
Eq.No Redox ReactionRedox Potential
Eo (volts)
1 Ag+(aq) + e- Ag(s) +0.7996
2 Bi3+(aq) + 3e- Bi(s) + 0.381
3 Cu2+(aq) + 2e- Cu(s) +0.3419
4 Sb3+(aq) + 3e- Sb(s) +0.11
5 W3+(aq) + 3e- W(s) +0.1
6 Pb2+(aq) + 2e- Pb(s) -0.1262
7 Sn2+(aq) + 2e- Sn(s) -0.1375
8 As3+(aq) + 3e- As(s) -0.32
9 Fe2+(aq) + 2e- Fe(s) -0.44
10 Ni2+(aq) + 2e- Ni(s) -0.4257
11 Zn2+(aq) + 2e- Zn(s) -0.7618
12 Mn2+(aq) + 2e- Mn(s) -1.185
Redox Corrosion MechanismRedox Corrosion Mechanismof Lead-Antimony Alloy – of Lead-Antimony Alloy – Kinetic IssuesKinetic IssuesMETAL-WATER INTERFACE METAL
ANODIC REGION
METAL
CATHODIC REGION
Pb(s) Pb2+ (aq) + 2e- Anodic Region:
Pb2+ Pb(OH)2 / PbOHCO3 PbO / PbO2
Cathodic Region:
O2 (g) + 2H2O + 4e- 4OH- (aq)
H2CO2(aq) + 2OH-(aq) CO3-(aq) + H2O
PbO2 + H2O+ 2e- PbO +2OH-
e- generated at anodic region released at the
cathodic region
Surface Area Increases due to porosity / frangibility
Sb(s) Sb3+(aq) + 3e-
Sb3+ (aq) Sb(OH)3 mildly acidic + High Redox potential ~2.0eV
Fe Fe2+ + 2e- fast Fe2+
+ O2 Fe3+ fast, Acidic Aq ion + high redox potential ~2.5eV
Sb3+(aq) + 3e- Sb(s)Fe2+ + 2e- Fe Fe3+
(aq) + e- Fe2+(aq)
CORROSION ACCERATED BY > ACIDITY, > SURFACE AREA &
< PASSIVATION
INITIAL CORROSION SLOWED BY PbO PASSIVATION
IRON >> CORROSIONIRON >> CORROSION
UK-5.56 Core; UK-5.56 Core; nominally nominally 10% Sb, 3.8%O 10% Sb, 3.8%O Polished un-etched cross-section Polished un-etched cross-section
© Copyright 2004 Cylenchar Limited© Copyright 2004 Cylenchar Limited
© Copyright 2004 Cylenchar Limited© Copyright 2004 Cylenchar Limited
US-5.56 Core; <1% Sb, >7-18%O US-5.56 Core; <1% Sb, >7-18%O Polished un-etched Polished un-etched
cross-sectioncross-section
Lead/Steel - Environmental Risk FactorsLead/Steel - Environmental Risk Factors►Lead shot and bullets from ‘secondary lead’ Lead shot and bullets from ‘secondary lead’
contain ‘Toxic’ lead oxide / sulphate.contain ‘Toxic’ lead oxide / sulphate.►Antimony and other impurities increase Antimony and other impurities increase
corrosion rates.corrosion rates.►Steel shot fired onto legacy lead Steel shot fired onto legacy lead High Redox High Redox
material + lower pH material + lower pH increases Pb and Sb increases Pb and Sb corrosion + Fe contaminants; e.g. Ni, Mn.corrosion + Fe contaminants; e.g. Ni, Mn.
►Steel shot Steel shot fast corrodingfast corroding Fe and Mn oxides Fe and Mn oxides ‘transport metal’ for heavy metals; e.g. Pb, ‘transport metal’ for heavy metals; e.g. Pb, Sb, As, etc.Sb, As, etc.
What should be the Risk status ofWhat should be the Risk status ofLead Projectiles,Lead Projectiles,
harmful irritant metalharmful irritant metal
or Toxic oxide?or Toxic oxide???
Does Steel solve or compound Does Steel solve or compound the problem?the problem?
The Properties of TungstenThe Properties of Tungsten►High density metal 19g/ccHigh density metal 19g/cc►m.pt >3,400m.pt >3,400ooC C W-Powder Technology W-Powder Technology►Inert, Insoluble and Non-toxic ???Inert, Insoluble and Non-toxic ???►Noble metal Noble metal High redox potential. High redox potential.►W readily oxidized in air at RT, rapid W readily oxidized in air at RT, rapid
oxidation above 200oxidation above 200ooCC## ►W powder is W powder is PYROPHORIC!PYROPHORIC!#"#"Tungsten, Properties, Chemistry, Technology of the element, Alloys, and Chemical Compounds" Tungsten, Properties, Chemistry, Technology of the element, Alloys, and Chemical Compounds"
by Erik Lassner and Wolf-Dieter Schubert, Kluwer Academic/Plenum Publishers 1999 by Erik Lassner and Wolf-Dieter Schubert, Kluwer Academic/Plenum Publishers 1999 ISBN 0-306-45053-4ISBN 0-306-45053-4
► Insoluble! – Low solubility in acids, Insoluble! – Low solubility in acids, soluble to alkali, soluble to alkali, and aqueous oxygenating environmentsand aqueous oxygenating environments: : Anodic Oxidation; (i) W + 8OHAnodic Oxidation; (i) W + 8OH-- WO WO44
2-2- + 6e + 6e-- + 4H + 4H22O O Cathodic reduction; (ii) OCathodic reduction; (ii) O2 2 + 2H + 2H22O + 4eO + 4e-- 4OH 4OH--
► Dissolution rate slow (30Dissolution rate slow (30µµm) pure W powder at 10%w/v m) pure W powder at 10%w/v in pure water in pure water ~10mgW/litre/day. ~10mgW/litre/day.
► Aqueous solubility of W metal Aqueous solubility of W metal 75mg/Litre at 38 75mg/Litre at 38ooC C equilibrium, i.e. pH 3.2. Passivates only below pH 4.equilibrium, i.e. pH 3.2. Passivates only below pH 4.
► HH22WOWO44.H.H22OO - pKa 3.6 and very soluble and colloidal.- pKa 3.6 and very soluble and colloidal.► Soil based electrolytes, Fe and Pb Soil based electrolytes, Fe and Pb increase solubility increase solubility
and dissolution significantly! E.g. FeOH.WOand dissolution significantly! E.g. FeOH.WO44(5H(5H220) 0) and PbWOand PbWO4 4 (Stolzite) sink effects.(Stolzite) sink effects.
#"#"Tungsten, Properties, Chemistry, Technology of the element, Alloys, and Chemical Compounds" Tungsten, Properties, Chemistry, Technology of the element, Alloys, and Chemical Compounds" by Erik Lassner and Wolf-Dieter Schubert, Kluwer Academic/Plenum Publishers 1999 by Erik Lassner and Wolf-Dieter Schubert, Kluwer Academic/Plenum Publishers 1999
ISBN 0-306-45053-4ISBN 0-306-45053-4
The Properties of TungstenThe Properties of Tungsten##
The Properties of TungstenThe Properties of Tungsten
SR Instrumentation Engineering Group Report, "Erosion/Corrosion of Machinable Tungsten in Water“, SR Instrumentation Engineering Group Report, "Erosion/Corrosion of Machinable Tungsten in Water“, Jeff T. Collins, Advanced Photon Source Experimental Facilities Division, SR Instrumentation Engineering Jeff T. Collins, Advanced Photon Source Experimental Facilities Division, SR Instrumentation Engineering
Group, November 30, 2000Group, November 30, 2000
Corrosion of Corrosion of machinable machinable tungsten steel tungsten steel by oxygenated by oxygenated water water
WW
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W
W
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W W
W
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WWW
W
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W
Redox Corrosion of Tungsten Powder in Alloy
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W W
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WWW
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W
M+
M+
M+
M+
M+
M+
M+
Redox Corrosion of Tungsten Powder in Alloy
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W03
WW
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W
W
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W
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W
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W
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W
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W W
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WW
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W
M+
M+
M+
M+
M+
M+
M+
W03
WO3
WO3
Redox Corrosion of Tungsten Powder in Alloy
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W03
WW
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W W
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WW
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W
M+
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M+
M+
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W03
WO3
WO3
M+
M+
Redox Corrosion of Tungsten Powder in Alloy
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W03
WW
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W W
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WW
W
M+
M+
M+
M+
M+
M+
M+
M+
M+
M+
M+
M+
W03
WO3
WO3
WO3
WO3
M+
M+
Redox Corrosion of Tungsten Powder in Alloy
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W
W
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W
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W W
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WW
W
M+
M+
M+
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M+
M+
M+
M+
M+
M+
M+
M+
W03
WO3
WO3
WO3
WO3
M+
M+
M+
M+
M+
M+
M+
M+
M+
H2W0
4
Redox Corrosion of Tungsten Powder in Alloy
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W W
W
W
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WW
WO3
M+
M+
M+
M+
M+
M+
M+
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M+
M+
M+
M+
W03
WO3
WO3
WO3
M+
M+
M+
M+
M+
M+
M+
M+
M+
W03
W03
W03
H2WO
4
H2W0
4
Redox Corrosion of Tungsten Powder in Alloy
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WO3
M+
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M+
W03
WO3
WO3
M+
M+
M+
M+
M+M+
M+
M+
M+
W03
W03
W03
H2WO
4
H2WO
4
H2W04
Redox Corrosion of Tungsten Powder in Alloy
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W W
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WO3
M+
M+
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M+
M+
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M+
M+
M+
M+
WO3
WO3
M+
M+
M+
M+
M+M+
M+
M+
M+
W03
W03
W03
WO 3
WO3
WO3
W03
W03
H2WO
4
H2WO
4
H2W0
4
H 2W0 4
Redox Corrosion of Tungsten Powder in Alloy
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WO3
WO 3
WO3
WO3
W03
Base metal matrix dissolves via redox induced corrosion.
Colloidal tungsten exposed and rendered soluble via oxidation.
pH falls giving deposition of non-protective WO3 and soluble isotungstates. If pH remains neutral or alkali, corrosion continues apace releasing tungstates.
WO42- salts formed with
matrix corrosion products and soil contaminants.
Redox Corrosion of Tungsten Powder in Alloy
Dissolution & Decay of Tungsten Polymer composite
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W03
WO3
Dissolution & Decay of Tungsten Polymer composite
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WO3
Dissolution & Decay of Tungsten Polymer composite
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W03
W03
WO3
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WO3
Dissolution & Decay of Tungsten Polymer composite
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WO3
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Dissolution & Decay of Tungsten Polymer composite
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WO3
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WO3
WO3
Dissolution & Decay of Tungsten Polymer composite
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W03
WO3
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WO3
Dissolution & Decay of Tungsten Polymer composite
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W03
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W03
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W03
W03
WO3
WO3
WO3
WO3
WO3
H 2WO 4
H2W0
4
Dissolution & Decay of Tungsten Polymer composite
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W03
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W03
H2W04
WO3
H2WO
4
WO 3
WO3
H2WO
4
H 2WO 4
H2W04
Dissolution & Decay of Tungsten Polymer composite
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W03
W03
W03
W03
W03
W03
WO3
WO3
WO3
WO3
WO3
WO3
H2W04
H2W04
H2W0
4
H 2WO 4
H2WO
4
H2WO
4
H 2WO 4
Dissolution & Decay of Tungsten Polymer composite
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W03
WO3
WO3
WO3
WO3
Oxidation and dissolution of tungsten
Assisted by physical rupture of matrix by reactive W oxides
Coincidental with, or preceded by decay of the polymer matrix.
Dissolution & Decay of Tungsten Polymer composite
WW
W
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W03
WO3
WO3
WO3
WO3
R1-CH2-CO-NH-CH2-R2 + H3O+
R1-CH2-CO2H + H2N-CH2-R2
R1-CH2-CO-NH-CH2-R2
R1-CH2-CO-NH-*CH-R2 + O2
R1-CH2-CO-NH-CO-R2 + H2O
Acid Hydrolysis
W / Cu free-radical induced oxidation
(Plastics Cancer)
Dissolution & Decay of Tungsten Polymer composite
Inherent Redox Instability of Tungsten Powder Inherent Redox Instability of Tungsten Powder Technology – Technology – e.g. Chang et al (1998)e.g. Chang et al (1998)
► ““When W was coupled to FeWhen W was coupled to Fe##, CDA , CDA (Cu-Ni Bronze)(Cu-Ni Bronze) and and Invar Invar (Ni-iron),(Ni-iron), significantly large current densities significantly large current densities were measured. This suggest that corrosion protection were measured. This suggest that corrosion protection schemes will need to be developed for W-alloys using schemes will need to be developed for W-alloys using these materials in the matrix.”these materials in the matrix.”
► Similar materials have been approved for sale in the US Similar materials have been approved for sale in the US as ‘NON-TOXIC” under US Fish & Wildlife as ‘NON-TOXIC” under US Fish & Wildlife Department regulations. (Submissions cite limited Department regulations. (Submissions cite limited duration in-vivo studies on waterfowl.)duration in-vivo studies on waterfowl.)
Ref: Galvanic Corrosion of Tungsten Coupled With Several Metals/Alloys; Chang F.C., Beatty J.H., Kane M.J., Beck J;
Army Research Lab, Aberdeen Proving Ground, MD
Inherent Redox Instability of Tungsten Powder Inherent Redox Instability of Tungsten Powder Technology – Technology – e.g. Meijer et al (1998)e.g. Meijer et al (1998)
► W-Ni alloys with Fe, Cu, Co, Mn and Ta studied in relation to use W-Ni alloys with Fe, Cu, Co, Mn and Ta studied in relation to use at Elgin AFB. 10 year projection/assumption: Average 0.55% w/w at Elgin AFB. 10 year projection/assumption: Average 0.55% w/w W and 0.036% w/w Ni over surface area to a depth of 1cm, with W and 0.036% w/w Ni over surface area to a depth of 1cm, with average particle size 0.5cm.average particle size 0.5cm.
► Bare alloy Bare alloy (Stock Rod, not heat treated)(Stock Rod, not heat treated) discs, (26-33 mm dia) in discs, (26-33 mm dia) in rainfall event model ‘drip tests’ over a ~6 hour period, yielded: rainfall event model ‘drip tests’ over a ~6 hour period, yielded:
WW at 8.9 - 98.1 mg/L (no soil) at 8.9 - 98.1 mg/L (no soil) NiNi at 5.4 - 33.7 mg/L (no soil) at 5.4 - 33.7 mg/L (no soil) NiNi at 4.5 - 247 mg/L (in soil) at 4.5 - 247 mg/L (in soil)
► Likely corrosion products include Cu-Ni and Ni Tungstates.Likely corrosion products include Cu-Ni and Ni Tungstates. Ref: Environmental Effects of Tungsten & Tantalum Alloys;
Mejier A, Wroblicky G, Thrung S & Marcell MW; GCX Albuquerque NM; 1998
Inherent Redox Instability of Tungsten Powder Inherent Redox Instability of Tungsten Powder Technology – Technology – e.g. Meijer et al (1998)e.g. Meijer et al (1998)
W in Bonze alloy subject to sea water. Bronze matrix preferentially dissolves.
W in Bonze alloy subject to ground water.
Tungsten particles preferentially dissolve and
give increased acidity.
WO3
W Grains
Ref: Environmental Effects of Tungsten & Tantalum Alloys;
Mejier A, Wroblicky G, Thrung S & Marcell MW; GCX Albuquerque NM; 1998
Inherent Redox Instability of Tungsten Powder Inherent Redox Instability of Tungsten Powder Technology – Technology – e.g. Meijer et al (1998)e.g. Meijer et al (1998)
W in Bonze alloy subject to ground water. Tungsten particles preferentially dissolve.
With increasing acidity get formation of a Yellow scale NB: H2WO4.H2O (Yellow), W03.2H20 (white)
WO3?
Ref: Environmental Effects of Tungsten & Tantalum Alloys;
Mejier A, Wroblicky G, Thrung S & Marcell MW; GCX Albuquerque NM; 1998
Inherent Redox Instability of Tungsten Powder Inherent Redox Instability of Tungsten Powder Technology – Technology – e.g.e.g. Meijer et al (1998) Meijer et al (1998)
► ““Tantalum and tungsten are strongly bound on mineral grains in Tantalum and tungsten are strongly bound on mineral grains in the soil zone and will remain in this zone indefinitely”the soil zone and will remain in this zone indefinitely”
► Unlikely to remain immobile, in our experience. Possibility of Unlikely to remain immobile, in our experience. Possibility of ‘soil saturation’ and/or ‘facilitated transport’ not considered. ‘soil saturation’ and/or ‘facilitated transport’ not considered. Dissolution tests done in absence of iron. Leach model sample Dissolution tests done in absence of iron. Leach model sample seriously flawed!seriously flawed!
► ““Tungsten and tantalum appear to have minimal human and Tungsten and tantalum appear to have minimal human and ecological impact based on the current available data” ecological impact based on the current available data”
► Scant evaluation of available tox. data!Scant evaluation of available tox. data!► ““Analysis of potential ecological risks indicates no unacceptable Analysis of potential ecological risks indicates no unacceptable
risks will result from use of tantalum and / or tungsten alloys in risks will result from use of tantalum and / or tungsten alloys in the testing of penetrator munitions”the testing of penetrator munitions”
► Independent comment: Independent comment: “largely inconclusive with regards to the “largely inconclusive with regards to the geochemical behaviour of tungsten and tungsten alloys”geochemical behaviour of tungsten and tungsten alloys”
Ref: Environmental Effects of Tungsten & Tantalum Alloys;
Mejier A, Wroblicky G, Thrung S & Marcell MW; GCX Albuquerque NM; 1998
► Rapid dissolution of W from both W-Nylon an W-Tin bullet Rapid dissolution of W from both W-Nylon an W-Tin bullet residues in sand column leaching studies:residues in sand column leaching studies:
deionised water, to 15.6 mg/L W. deionised water, to 15.6 mg/L W. simulated sea water, to 66 mg/L W.simulated sea water, to 66 mg/L W. simulated rain water, to 105 mg/L W.simulated rain water, to 105 mg/L W.► On aging 130On aging 130ooC, 48 days leach rates to 9,510 mg/L W. C, 48 days leach rates to 9,510 mg/L W. ► W-Nylon residues with iron piercing tips faired least well.W-Nylon residues with iron piercing tips faired least well.► Mixed W and WOMixed W and WO33 in rainwater, to 462 mg/L W. in rainwater, to 462 mg/L W. ► Mixed W, WOMixed W, WO33 and H and H22WOWO44 in rainwater, to 2,660mg/L W. in rainwater, to 2,660mg/L W.► ““It appeared that the tungsten powder oxidizes to form tungsten It appeared that the tungsten powder oxidizes to form tungsten
oxide, which is insoluble in water and thus relatively stable in oxide, which is insoluble in water and thus relatively stable in the environment.” the environment.”
Inherent Redox Instability of Tungsten Powder Inherent Redox Instability of Tungsten Powder Technology – Technology – e.g.e.g. Middleton (1998) Middleton (1998)
Ref: Elimination of Toxic Heavy Metals from Small Caliber Ammunition. Middleton J., SERDIP Report, ARDEC Picatinny 1998
Inherent Redox Instability of Tungsten Powder Inherent Redox Instability of Tungsten Powder Technology – Technology – e.g.e.g. Middleton (1998) Middleton (1998)
► W uptake by Beans and Rye Grass, Growth stunted. W uptake by Beans and Rye Grass, Growth stunted. Possibilities for phyto-remediation?Possibilities for phyto-remediation?
► Earthworm toxicity study shows weight loss. W-Tin Earthworm toxicity study shows weight loss. W-Tin fared better than Pb fared better than Pb - Worms on walls of the W test bin!- Worms on walls of the W test bin! “Earthworms were not adversely affected” “Earthworms were not adversely affected” Worm aversion test FAIL! Worm aversion test FAIL!
► W-Nylon effect on earthworms not studied. W-Nylon effect on earthworms not studied. Too acidic?Too acidic?► Earthworms in long term study contained 213ppm W:- Earthworms in long term study contained 213ppm W:-
Risk to food chain?Risk to food chain?► W binds strongly to soils/biomass. W binds strongly to soils/biomass. ‘Twin edged ‘Twin edged
sword.’ Other metals may bind strongly to colloidal W!sword.’ Other metals may bind strongly to colloidal W! Ref: Elimination of Toxic Heavy Metals from Small Caliber Ammunition.
Middleton J., SERDIP Report, ARDEC Picatinny 1998
Inherent Redox Instability of Tungsten Powder Inherent Redox Instability of Tungsten Powder Technology Technology
Corroding W-Nylon round in situ. Massachusetts Military Reservation.
Picture courtesy of Mark Begley Commonwealth of Massachusetts Environmental Management Commission
© Copyright 2004 Cylenchar Limited© Copyright 2004 Cylenchar Limited
ECOMASS 10002D95, Tungsten ECOMASS 10002D95, Tungsten in polyamide copolymer, 11g/cc in polyamide copolymer, 11g/cc
Fresh Surface, injection moulded Fresh Surface, injection moulded tile. Mole Ratio W:O 1:3.5tile. Mole Ratio W:O 1:3.5
© Copyright 2004 Cylenchar Limited© Copyright 2004 Cylenchar Limited
ECOMASS 10002D95 Aged Surface, ECOMASS 10002D95 Aged Surface, Water 98Water 98ooC 3 hr. Mole Ratio W:O 1:4. C 3 hr. Mole Ratio W:O 1:4.
Erosion & Oxidation. Carbon Matrix Erosion & Oxidation. Carbon Matrix disappears. Ca detecteddisappears. Ca detected
Tungsten – ToxicityTungsten – Toxicity► Oral Toxicity:Oral Toxicity:
W – Irritant, LDW – Irritant, LD5050 Rat 2-5g/Kg, WO Rat 2-5g/Kg, WO33 LD LD5050 Rat Rat 840-1,050mg/Kg. - Mildly Toxic840-1,050mg/Kg. - Mildly Toxic
► Soluble W compounds are Toxic.Soluble W compounds are Toxic. Sub-acute effects include; Sub-acute effects include; weight loss, breathing problems, blood changes, decreased sperm weight loss, breathing problems, blood changes, decreased sperm motility with genetic changes, non-specific neurological motility with genetic changes, non-specific neurological disorders including tremors, adverse effects on the liver, spleen disorders including tremors, adverse effects on the liver, spleen and kidneys, molybdenum deficiency, non-specific metabolic and kidneys, molybdenum deficiency, non-specific metabolic changes.changes. (Lit. Rev. Haneke 2003)(Lit. Rev. Haneke 2003)
► Cancer:Cancer: - Mildly Carcinogenic – Females at Greater Risk. - Mildly Carcinogenic – Females at Greater Risk. 5ppm W in drinking water over lifetime 5ppm W in drinking water over lifetime produced tumours in 65% of female rats and 15% male rats. produced tumours in 65% of female rats and 15% male rats. (Schroder & Mitchener 1975)(Schroder & Mitchener 1975) Lung cancer mortality in tungsten miners Lung cancer mortality in tungsten miners has been attributed to silicosis. Recent studies indicate no link has been attributed to silicosis. Recent studies indicate no link between the silicosis and lung cancer. between the silicosis and lung cancer. (Chen et al 1994)(Chen et al 1994)
Tungsten – ToxicityTungsten – Toxicity►Cancer promoterCancer promoter::
Mammary cancer promoting effect of tungsten, an antagonist of Mammary cancer promoting effect of tungsten, an antagonist of molybdenum, noted in mice molybdenum, noted in mice (Wei et al 1987).(Wei et al 1987). Mixed metal Tungsten Mixed metal Tungsten ore increases the growth rate of leukemia cellsore increases the growth rate of leukemia cells (Witten et al 2005)(Witten et al 2005)
►Synergistic effectsSynergistic effects: : The toxicity of Co is increased by the presence of WC. The toxicity of Co is increased by the presence of WC. ((RoesemsRoesems et al et al
1997)1997) WC-Co is more genotoxic than Co and WC alone. WC-Co is more genotoxic than Co and WC alone. (De Boeck et (De Boeck et al 2003)al 2003)
►DNA AffecterDNA Affecter:: TTungsten particle bombardment used to cleave DNA in creation ungsten particle bombardment used to cleave DNA in creation of GM organisms. of GM organisms.
► Tungsten metal particles in suspension promote breakage of Tungsten metal particles in suspension promote breakage of Cellular DNA, The rate of DNA self repair, not high enough to Cellular DNA, The rate of DNA self repair, not high enough to restore all genome functions. restore all genome functions. potential for adverse effects potential for adverse effects (Krysiak et al 1999).(Krysiak et al 1999).
Tungsten – Toxicity DataTungsten – Toxicity Data►Reproductive Affecter / TeratogenReproductive Affecter / Teratogen : :
Oral Rat, 1.2 mg/kg (30- 35 week prior to copulation Oral Rat, 1.2 mg/kg (30- 35 week prior to copulation and 1-2 weeks pregnant)and 1-2 weeks pregnant), , Musculoskeletal defects and Musculoskeletal defects and embryonic lethality.embryonic lethality. ((Mezhdunarodnaya Kniga, 1936 and Mezhdunarodnaya Kniga, 1936 and 1939 1939 respectively)respectively) / / Dangerous Properties of Industrial Materials, 7th Ed., by N. Irving Sax Dangerous Properties of Industrial Materials, 7th Ed., by N. Irving Sax and Richard J. Lewis. and Richard J. Lewis.
► ““There is anecdotal evidence of tungsten being a There is anecdotal evidence of tungsten being a teratogen or a substance which causes deformities in teratogen or a substance which causes deformities in developing fetus. However, other dietary and cultural developing fetus. However, other dietary and cultural factors could not be ignored in these studies. Thus factors could not be ignored in these studies. Thus tungsten is considered to be an experimental teratogen tungsten is considered to be an experimental teratogen that has experimental reproductive effectsthat has experimental reproductive effects””
Toxicity of tungsten, molybdenum and tantalum and the environmental and occupational laws associated with their manufacture, use and disposal. Kerwien S.C., ARDEC
Picatinny Arsenal NJ, Management Engineering 1996
Tungsten Powder Technology Projectile Toxicity Tungsten Powder Technology Projectile Toxicity Miller et al (2005)Miller et al (2005)
► Rats implanted with, high and low Rats implanted with, high and low dose W-Ni alloy and Ni alloy.dose W-Ni alloy and Ni alloy.
► Noticeable changes in the animals Noticeable changes in the animals blood and liver function after 1 blood and liver function after 1 month.month.
► Aggressive tumours around the Aggressive tumours around the implant within 5 months.implant within 5 months.
► 100% of test subjects developed 100% of test subjects developed tumours.tumours.
► Cancers metastasised to the lungs.Cancers metastasised to the lungs.► High dose W alloy implants High dose W alloy implants
developed tumours faster than low developed tumours faster than low dose, and faster than nickel, a dose, and faster than nickel, a known carcinogenknown carcinogen..
Kalinic FJ, Emond CA, Calton TK, Mog SR, Colemen GD, Kordell JE, Miller AC, McClain DE, Embedded Weapons-Grade Tungsten Alloy Shrapnel Rapidly Induces Metastatic High Grade Rhabdomyosarcomas in F344 Rats (2005)
Tungsten – EcotoxicityTungsten – Ecotoxicity► Soluble W toxic to red worms , plants, microbes. Soluble W toxic to red worms , plants, microbes.
0.01μg/L in soil microbial yield reduce 8%. 0.01μg/L in soil microbial yield reduce 8%. ‘Volume of Toxic Influence’.‘Volume of Toxic Influence’. Tungsten particles had Tungsten particles had ability to affect microbial communities at >10 times the ability to affect microbial communities at >10 times the radius of the particle. radius of the particle. (Strigul et al, 2003)(Strigul et al, 2003)
► 3% (NH3% (NH44))22WOWO44/WO/WO33 incubated in soil for 3 months, 95% incubated in soil for 3 months, 95%
death of soil microbe population. death of soil microbe population. (Dermatas et al, 2004)(Dermatas et al, 2004) ► 1% W incubated in soil for 1 year significant death of soil 1% W incubated in soil for 1 year significant death of soil
microbe population 68%. Toxic to nematodes, mites and microbe population 68%. Toxic to nematodes, mites and ticks. ticks. (Braida et al, 2004)(Braida et al, 2004)
► NB:Tungstates - KNOWN PESTICIDES & BIOCIDES.NB:Tungstates - KNOWN PESTICIDES & BIOCIDES.
W - Environmental Risk FactorsW - Environmental Risk Factors►W-Powder technology potentially unstable.W-Powder technology potentially unstable.►‘‘INSOLUBLE’, irritant W powder readily oxidises INSOLUBLE’, irritant W powder readily oxidises
to harmful and toxic ‘SOLUBLE’ W oxides.to harmful and toxic ‘SOLUBLE’ W oxides.►Current W-materials contaminated?Current W-materials contaminated?►Frangible rounds Frangible rounds maximise risk. maximise risk.►Redox effect Redox effect corrosion of legacy metals. corrosion of legacy metals.►Lower pH Lower pH faster corrosion and leaching. faster corrosion and leaching.►Colloidal W, a potential ‘transport metal’.Colloidal W, a potential ‘transport metal’.
W - Environmental Risk FactorsW - Environmental Risk Factors►W not fully toxicologically evaluated. However, W not fully toxicologically evaluated. However,
significant data implicating W as a reproductive significant data implicating W as a reproductive affecter and cancer promoter.affecter and cancer promoter.
►Toxic to flora and fauna.Toxic to flora and fauna.►Uptake by plants and invertebrates Uptake by plants and invertebrates Food Chain. Food Chain.►Prior risk appraisals flawed and inconclusive. Prior risk appraisals flawed and inconclusive.
Probability and severity of risk understated Probability and severity of risk understated ►Promotion of W as Promotion of W as insolubleinsoluble, , inertinert and and non-toxicnon-toxic
has lead to inappropriate and widespread use.has lead to inappropriate and widespread use.
Tungsten,Tungsten,
inert, insoluble and non-toxicinert, insoluble and non-toxic
or the New Asbestos?or the New Asbestos?
??
For further information contact:For further information contact:
Dr Peter J. HurleyDr Peter J. Hurley
Blake International LimitedBlake International Limited
Tel: +44-(0)1484-517417Tel: +44-(0)1484-517417
Fax: +44-(0)1484-516098Fax: +44-(0)1484-516098
e-mail: [email protected]: [email protected]
