Documents\Palladium-contents. Pdf

EHC 226: Palladium
iv
3.
SOURCES OF HUMAN AND ENVIRONMENTAL EXPOSURE 30
3.1
Natural occurrence
30
3.2
Anthropogenic “sources” of palladium
30
3.2.1
Production levels and processes for 
palladium metal
30
3.2.1.1 Production processes
31
3.2.1.2 Recycling
32
3.2.2
Processes for the production of important 
palladium compounds
32
3.2.3
Uses of palladium metal
33
3.2.3.1 Electronics and electrical
technology
33
3.2.3.2 Dental materials and other 
medical materials
35
3.2.3.3 Automobile exhaust catalysts
35
3.2.3.4 Catalysts in chemical processes
36
3.2.3.5 Fine jewellery and (optical) 
instruments
36
3.2.4
Uses of important palladium compounds
37
3.3
Emissions during production and use
38
3.3.1
Emissions into air
38
3.3.1.1 Production and fabrication losses
38
3.3.1.2 Losses from automotive exhaust emission
control catalysts
39
3.3.1.3 Experimental results with 
platinum-type automobile catalysts
to estimate palladium emissions
40
3.3.2
Emissions into water
41
3.3.3
Emissions into soil
41
4.
ENVIRONMENTAL TRANSPORT, DISTRIBUTION
AND TRANSFORMATION
42
4.1
Transport and distribution between media
42
4.2
Transformation and removal
43
4.2.1
Abiotic
43
4.2.2
Biotic
43

---

v
4.3
Bioaccumulation
44
4.3.1
Aquatic organisms
44
4.3.2
Terrestrial organisms
44
4.4
Ultimate fate following use
45
5.
ENVIRONMENTAL LEVELS AND HUMAN 
EXPOSURE
46
5.1
Environmental levels
46
5.1.1
Air
46
5.1.2
Dust
47
5.1.3
Soil
47
5.1.4
Sludges
50
5.1.5
Sediments
50
5.1.6
Water
51
5.1.6.1 Fresh water
51
5.1.6.2 Seawater
52
5.1.7
Biota
52
5.1.7.1 Plants
52
5.1.7.2 Animals
54
5.2
Exposure of the general population
55
5.2.1
Levels found in the general population
55
5.2.2
Food
56
5.2.3
Drinking-water
59
5.2.4
Iatrogenic exposure
60
5.2.4.1 In vitro studies
60
5.2.4.2 Clinical studies
62
5.3
Occupational exposure during manufacture, 
formulation or use
64
5.3.1
Workplace concentrations
64
5.3.2
Human monitoring data
65
6.
KINETICS AND METABOLISM IN LABORATORY ANIMALS
AND HUMANS
67
6.1
Absorption
67
6.1.1
Absorption in animals
67
6.1.1.1 Salts or complexes of palladium
67
6.1.1.2 Palladium metal or metal oxides
68
6.1.2
Absorption in humans
68

---

EHC 226: Palladium
vi
6.2
Distribution
68
6.2.1
Animal studies
68
6.2.1.1 Distribution in organs and blood
68
6.2.1.2 Transfer to offspring
72
6.2.1.3 Subcellular distribution
73
6.2.2
Human studies
73
6.3
Metabolic transformation
73
6.4
Elimination and excretion
74
6.5
Retention and turnover
75
6.6
Reaction with body components
76
7.
EFFECTS ON LABORATORY MAMMALS AND
IN VITRO TEST SYSTEMS
78
7.1
Single exposure
78
7.2
Short-term exposure
83
7.3
Long-term exposure
87
7.4
Irritation and sensitization
89
7.4.1
Skin irritation
89
7.4.2
Eye irritation
90
7.4.3
Sensitization
90
7.5
Reproductive and developmental toxicity
97
7.6
DNA interactions and mutagenicity
97
7.6.1
Interaction with DNA 
97
7.6.2
Mutagenicity
98
7.7
Carcinogenicity
 98
7.8
Effects on cellular functions
101
7.8.1
Miscellaneous cytotoxic effects
101
7.8.2
Antineoplastic potential
103
7.8.3
Enzyme inhibition
104
7.9
Other special studies
104
7.9.1
Nephrotoxicity
104
7.9.2
Neurotoxicity
107
7.10
Toxicity of metabolites
107
7.11
Mechanism of toxicity/mode of action
107

---

vii
8.
EFFECTS ON HUMANS
109
8.1
General population exposure
109
8.1.1
Effects due to exposure to palladium 
dust emitted from automobile catalytic 
converters
109
8.1.2
Effects after iatrogenic exposure
109
8.1.2.1 Dentistry
109
8.1.2.2 Cancer therapy
117
8.1.2.3 Other therapeutic uses
117
8.1.3
Effects after exposure from other sources
118
8.1.4
Characteristics of palladium sensitivity
118
8.2
Occupational exposure
129
8.2.1
Health effects due to metal (PGM) refinery processes
129
8.2.2
Health effects due to use or processing of 
palladium-containing products
129
8.2.2.1 Dental technicians
129
8.2.2.2 Automobile industry workers
130
8.2.2.3 Others
130
8.3
Subpopulations at special risk
132
8.4  
Carcinogenicity and other effects
132
9.
EFFECTS ON OTHER ORGANISMS IN THE LABORATORY
AND FIELD
133
9.1
Laboratory experiments
133
9.1.1
Microorganisms
133
9.1.2
Aquatic organisms
134
9.1.2.1 Plants
134
9.1.2.2 Invertebrates
134
9.1.2.3 Vertebrates
135
9.1.3
Terrestrial organisms
136
9.1.3.1 Plants
136
9.1.3.2 Invertebrates
137
9.1.3.3 Vertebrates
137
9.2
Field observations
137

---