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Identity, Physical and Chemical Properties, Analytical Methods
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interlaboratory   comparison  programmes  for the determination of
environmental palladium are not yet available.
2.3.3
Analysis
Analytical methods are summarized in Table 5. Current measure-
ment techniques do not allow separate species of palladium (metal or
palladium(II) compounds) to be differentiated when more  than one form
is  present. Almost all measurements of palladium in environmental and
other samples to date have been for total palladium.
In analytical laboratories, physical methods have widely  replaced
wet chemical and colorimetric analytical methods for reasons of econ-
omy  and speed. Methods such as  neutron activation analysis, total
reflection X-ray fluorescence analysis  and, above all, ICP-MS and GF-
AAS are  used after appropriate enrichment procedures. If palladium is
brought into solution by appropriate separation methods, all PGMs can
be determined in the presence of each other by X-ray fluorescence or
ICP analysis, for example.
Using ICP-MS, it is  possible  to detect palladium in urine or blood
samples  of persons without occupational exposure, whereas  the detec-
tion limits of A A S methods are higher by a factor of about 3 or more
(see Table 5).

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Table 5. Analytical methods for palladium determination
Matrix/medium
Sample treatment
(decomposition/separation)
Determinatio
n method
a
Limit of detection
b
Comments
c
References
Air
Particulate matter
air filtration through Teflon
membrane
XRF
0.001 µg/m
3
 
d
 
Lu et al. (1994)
Particulate matter
air filtration through Teflon
membrane
XRF
0.0005 µg/m
3
 
d
 
Gertler (1994)
Car exhaust
Particulate matter
from exhaust pipe
of cars
bubbling through nitric acid
absorbent solution and filtering
through cellulose ester filter;
mineralization: acid-assisted
microwave digestion
quadrupole
ICP-MS
3.3 ng/litre
mathematical
corrections for spectral
interferences
Moldovan et al. (1999);
Gomez et al. (2000)
Water
Aqueous solution
extraction with 1-decyl-N,N
N
-diphenyl-
isothiouronium bromide in variety of
organic liquids
AAS
<0.1 mg/litre
co-extraction of noble
metals
Jones et al. (1977)
Aqueous solution
extracted by bismuth diethyldithio-
carbamate into chloroform at pH 3.5
NAA
0.4 ± 0.1 ng/litre
Pd(II); 5 litres of river
water were extracted
Shah & Wai (1985)
Water samples
2,2
N
-dipyridyl-3-(4-amino-5-
mercapto)-1,2,4-triazolylhydrazone,
supported on silica gel column
AAS
4 µg/litre
Pd(II); samples were
preconcentrated by a
factor of 100
Samara & Kouimtzis
(1987)

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Table 5 (contd).
Matrix/medium
Sample treatment
(decomposition/separation)
Determinatio
n method
a
Limit of detection
b
Comments
c
References
Spring water
sample
adsorption on sulfonated dithizone-
loaded resin; direct introduction into
the furnace
GF-AAS
22 ± 2 ng/litre
Chikuma et al. (1991)
Pure waters
acidification and adsorption onto
activated charcoal; palladium is
redissolved with aqua regia following
ashing of the charcoal
ICP-MS
0.3–0.8 ng/litre 
1-litre sample volume;
preconcentration factor
of 200
Hall & Pelchat (1993)
Groundwater
only filtration and acidification with
nitric acid
ICP-MS
5 ng/litre
convenient for
determination of
multimetals; strontium
interferes with 
105
Pd
Stetzenbach et al.
(1994)
Aqueous solution
preconcentration in a microcolumn
loaded with N,N-diethyl-N
N
-benzoyl-
thiourea
GF-AAS
13–51 ng/litre 
analysis of ethanol
eluate 
Schuster & Schwarzer
(1996)
Geological materials
Rock, water
extraction with selenium via a co-
precipitation technique
ZAAS
1–3 ng/ml
Eller et al. (1989)
Various
geological
materials
extraction with aqua
regia/hydrofluoric acid, co-
precipitation with tellurium
AAS
0.031 µg/ml
analyte solution
determination in
solution using an argon-
stabilized arc
Tripkovic et al. (1994)
Various
geological
materials
fire assay (nickel sulfide)
GF-AAS
2 µg/kg
Zereini (1996)

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Table 5 (contd).
Matrix/medium
Sample treatment
(decomposition/separation)
Determinatio
n method
a
Limit of detection
b
Comments
c
References
Soil and dust
Roadside dust
dissolution by wet ashing; isolation
by anion exchange
FAAS
15 µg/kg
d
Hodge & Stallard
(1986)
Roadside dust,
soil
fire assay (nickel sulfide); digestion
with hydrochloric acid
flameless
AAS
2 µg/kg
appropriate for
geological materials
Zereini et al. (1993)
Human blood and urine
Blood
wet ashing with nitric acid/perchloric
acid; extraction with tri-n-octylamine
from hydrochloric acid solution
flameless
AAS
0.4 µg/litre 
determinations on
spiked samples; quantity
15 ml
Tillery & Johnson
(1975)
Blood, urine
urine: evaporation of urine samples
blood: wet ashing with nitric acid/
perchloric acid; extraction with tri-n-
octylamine from hydrochloric acid;
aspiration into air–acetylene flame 
AAS
blood:
0.9 µg/100 ml; 
urine: 0.3 µg/litre
Johnson et al.
(1975a,b)
Whole blood,
urine
decomposition with nitric acid/
perchloric acid 
flameless
AAS
0.01 µg/g blood;
0.003 µg/g urine
rapid method
(5-g blood sample)
(50-g urine sample)
Jones (1976)
Urine
direct measurement
ICP-AES
16 ng/ml
5-µl samples
Matusiewicz & Barnes
(1988)

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