View
219
Download
1
Category
Tags:
Preview:
DESCRIPTION
Polesello Alchilfenoli
Citation preview
Twinning Bulgaria Twinning Bulgaria ItaliaItaliaTraining 3.3Training 3.3
Simitli 17Simitli 17--19 February 200919 February 2009
Analytical Methods for PAH, PBDE, C10-13 Chloroalkanes andC10 13 Chloroalkanes and
alkylphenols
Stefano POLESELLOStefano POLESELLOStefano POLESELLOStefano POLESELLOIstituto di Ricerca sulle AcqueIstituto di Ricerca sulle Acque--CNRCNRSezione di BrugherioSezione di Brugherio
l ll @i itl ll @i itpolesello@irsa. cnr.itpolesello@irsa. cnr.it
ALKYLPHENOLS
Status
ALKYLPHENOLS
Priority Substance Standard Principle
inland otherinland waters
other waters
Nonylphenols3) ISO 18857-1:2005 GC/MS C C
Octylphenol (4-(1,1,3,3)-Tetramethylbutylphenol
ISO 18857-1:2005 GC/MS A D
LOQ = 0.1 g/L for NP and 0.0033 g/L for OPg/L for NP and 0.0033 g/L for OP
Blank interferences for NPBlank interferences for NP
At my knowledge, the only CRM available for NP is No validation for whole water
WWTP sludge (www.eurofins.dk).
Alkylphenols: analytical methodsAlkylphenols: analytical methodsAlkylphenols: analytical methodsAlkylphenols: analytical methods
zz Liquid chromatographyLiquid chromatography ESI (ESI (--) (LC) (LC--MS/MS) (MS/MS) (ASTM WK15211ASTM WK15211) Fluorimeter (Fluorimeter (IRSA method, ItalyIRSA method, Italy))
zz Gas chromatography with MS detection (Gas chromatography with MS detection (ASTM ASTM WK1521WK1521; ASTM D7065 06)
Wi h d i i i (Wi h d i i i (ISO 188ISO 188 1 2001 200 )) Without derivatisation (Without derivatisation (ISO 18857ISO 18857--1:20051:2005)) With derivatisation with MSTFA (With derivatisation with MSTFA (ISO 18857ISO 18857--2:draft2:draft))
ExtractionExtractionExtractionExtractionzz WaterWater
LLE with toluene (LLE with toluene (ISO 18857ISO 18857--1:2005; ASTM D70651:2005; ASTM D7065--0606)) Continuous LLE (Continuous LLE (ASTM WK1521ASTM WK1521) SPE with C18, SDVB (SPE with C18, SDVB (ISO 18857ISO 18857--2:draft ; ASTM 2:draft ; ASTM
WK15211WK15211)
zz Solid samples (SPM, sediment)Solid samples (SPM, sediment) Soxhlet or ASE extraction withSoxhlet or ASE extraction withzzMEOH (MEOH (IRSA method, Italy)IRSA method, Italy)zzAcetone/esanoAcetone/esano
zz LCLC:: single peak for each isomeric mixtures of a single single peak for each isomeric mixtures of a single
compoundcompound but often broad peaksbut often broad peaks Possibility to determine ethoxylatesPossibility to determine ethoxylates Columns: preferred polar embedded or reverse Columns: preferred polar embedded or reverse
phase such as pphase such as phenylhexylhenylhexyl
zz GCGC Different peaks for about every isomersDifferent peaks for about every isomers ...but integration must be the sum of a group of ...but integration must be the sum of a group of
peakspeaks Variability of NP without derivatisation (Adsorption?)Variability of NP without derivatisation (Adsorption?)
GC without derivatisation:GC without derivatisation:ISO 18857ISO 18857--1:20051:2005
zz Compounds:Compounds: 4n4n--NP, 4NP, 4--NP NP (branched)(branched), 4, 4--terttert--OPOPzz Range : Range : 0.005 to 0.2 g/L; drinking, surface 0.005 to 0.2 g/L; drinking, surface
d t td t tand waste watersand waste waterszz m/zm/z 135 + 107135 + 107zz Extraction: Extraction: LLE with tolueneLLE with toluenezz ClaenClaen--up: up: silica columnsilica columnzz Detection: Detection: GCGC--MS in SIM (m/z=107/135)MS in SIM (m/z=107/135)zz Quantification:Quantification: ESTD e ISTD: ESTD e ISTD: 1313CC66--ringring--labelled 4labelled 4--nn--66 gg
nonylphenol m/z 113nonylphenol m/z 113
ISO 18857ISO 18857 1 2005 Water quality1 2005 Water quality determination of selected alkylphenolsdetermination of selected alkylphenolsISO 18857ISO 18857--1, 2005, Water quality 1, 2005, Water quality determination of selected alkylphenols determination of selected alkylphenols PartPart 1: Method for non1: Method for non--filtered samples using liquid extraction and gas filtered samples using liquid extraction and gas chromatography with mass selective detection. chromatography with mass selective detection.
ISO 18857ISO 18857 1:20051:2005ISO 18857ISO 18857--1:20051:2005
GC GC withwith derivatizazionderivatizazion::ISO 18857ISO 18857--2:2:draftdraft
zz Analytes:Analytes: NP, OP, OP(1,2)EO, NP(1,2)EO and BPANP, OP, OP(1,2)EO, NP(1,2)EO and BPAzz Range:Range: 0 005 to 0 2 g/L (OP and OP(1 2)EO)0 005 to 0 2 g/L (OP and OP(1 2)EO)zz Range: Range: 0.005 to 0.2 g/L (OP and OP(1,2)EO)0.005 to 0.2 g/L (OP and OP(1,2)EO)
0.030 to 0.2 g/L (NP and NP(1,2)EO)0.030 to 0.2 g/L (NP and NP(1,2)EO)0 05 to 0 2 g/L (BPA)0 05 to 0 2 g/L (BPA)0.05 to 0.2 g/L (BPA)0.05 to 0.2 g/L (BPA)(drinking water, ground and surface water) (drinking water, ground and surface water)
zz Range :Range : 0.1 to 50 g/L (waste water)0.1 to 50 g/L (waste water)gg g ( )g ( )zz Extraction: Extraction: SPE (styreneSPE (styrene--divinylbenzene) without filtrationdivinylbenzene) without filtrationzz Derivatizazion: Derivatizazion: MSTFA TrifluoroMSTFA Trifluoro--NN--methylmethyl--NN--yy
(trimethylsilyl)acetamide(trimethylsilyl)acetamidezz Detection: Detection: selected ion monitoringselected ion monitoringzz Quantification:Quantification: ESTD and ISTD: ESTD and ISTD: 1313CC66--ringring--labelledlabelled
ISO 18857ISO 18857 2:2:draftdraft ((ESTD+ISTDESTD+ISTD))ISO 18857ISO 18857--2:2:draftdraft ((ESTD+ISTDESTD+ISTD))
ISO 18857ISO 18857--2:2:draftdraft((spikedspiked water water extract+ISTDextract+ISTD))
Intercalibration ISO 18857-1:2005
Bavarian Water Management Agency Munich, Germany according Bavarian Water Management Agency Munich, Germany according to ISO 5725to ISO 5725
17 labs from 6 countries 3 water samples (duplicate) 3 water samples (duplicate)
surface (0.005 to 0.05 g/L) surface (0.05 to 0.2 g/L)( g ) wastewater (0.1 to 25 g/L)
calibration solution
Intercalibration trial
matrix variables N NAP% X xrefREC
% SR CVR% ref % R R
1 surface 4-tert-OP 26 7.1 16.6 19.0 87.3 4.16 25.14-NP 22 15.4 28.7 23.0 124.9 16.4 57.2
2 surface 4-tert-OP 26 13.3 66.8 75.0 89.0 17.9 26.8
4 NP4-NP 22 26.7 82.8 90.0 92.0 15.6 18.8
3 waste 4-tert-OP 30 0 1400 1400 100 1 0 45 32 03 waste 30 0 1400 1400 100.1 0.45 32.0
4-NP 30 6.3 2020 1800 112.2 0.64 31.5
Octylphenol: 19 1400 ng/L ; reproducibility: 19 e 57 %Octylphenol: 19-1400 ng/L ; reproducibility: 19 e 57 %Nonylphenol: 23 -1800 ng/L; reproducibility: 25 e 32 %
PBDEPBDE
z Standardised method does not exist for water: Pentabromodiphenylether (PDBE) p y ( ) Method ISO: only for sediment (SPM?) Under development (CEN method) Under development (CEN method)
LOQ = 0.066 ng/L
POLYBROMINATED DIPHENYLETHERS (PBDEs)
Technical mixtures
) Penta-BDEMixture of tetra-, penta-, and hexabromodiphenylethers;BDE-47, BDE-99, BDE-100, BDE-153 and BDE-154 , , ,constitute more than 80% of the technical product
) Octa-BDE) Octa-BDEMixture of hepta-, octa- and nonabromodiphenylethers;BDE-183 can be used as indicator compound
) Deca-BDEDecabromodiphenylether makes up more than 97% Decabromodiphenylether makes up more than 97%
PBDE: sum of BDE-28, BDE-47, BDE-99, BDE-100, BDE-153, BDE-154
CAS Number: 32534-81-9 Log KOW: 6.57
z No standardised method for the determination of PBDE in z No standardised method for the determination of PBDE in water available! (CEN Method under development for whole water)
z ISO 22032:2006 Determination of selected polybrominated in sediment: diphenylethers (PBDE) in sediment and
l d sewage sludge Method using extraction and gas chromatography/mass
spectrometry
EQS = 0.5 ng/L; Other Surface Waters =0.2 ng/LLOQ = 0 066 ng/LLOQ = 0.066 ng/L
Methods for PBDE analysis in water are available:
z EPA Method 527 employs solid-phase extraction with analysis by gas chromatography/mass spectrometry MDL is fairly high (0.39 g/l)
z EPA Method 1614 2007 applies HRGC/HRMS for the z EPA Method 1614, 2007 applies HRGC/HRMS for the analysis of PBDE in water, soil, sediment and tissue. MDL for BDE 99 is 0.04 ng/l.
Large volume methods
There are a few reports on extremely low levels of PBDEs in surface water samples. The authors enriched 100 and 2500 L of water The authors enriched 100 and 2500 L of water, respectively, on XAD resin. SPME has been proposed to extract selected BDE congeners from water samples by Polo et al 2004 et al. 2004.
PBDEsAnalytical Methods
) Gas chromatography with electron capture detection (GC-ECD)) Gas chromatography with atomic emission detection (GC-AED)) Gas chromatography with electron impact mass spectro-
metric detection at low resolution (GC-LRMS)
g p y ( )
( )
) Gas chromatography with electron impact mass spectro-metric detection at high resolution (GC-HRMS)g ( )
) Gas chromatography with electron capture negative ionisation mass spectrometric detection (GC-ECNI-MS)p ( )
CEN-ISO Method for sedimentGC-ECNI-MS
Experimental Conditions:Experimental Conditions:
Matrix: Sediment, suspended particulate matter (SPM) Compounds: BDE 47 BDE 99 BDE 100 BDE 153Compounds: BDE-47, BDE-99, BDE-100, BDE-153,
BDE-154, (BDE-183, BDE-209)Limit of determination: 0.01 to 0.05 g/kg (test portion 10 g)Extraction: Soxhlet extraction with toluene orExtraction: Soxhlet extraction with toluene or
hexane/acetoneClean-up: Multi-layer column chromatography on silica gelDetection: GC-ECNI-MS in the selected ion monitoringDetection: GC ECNI MS in the selected ion monitoring
mode (m/z=79/81 for all congeners except BDE-209)
Quantification: ISTD: BDE-77, BDE-181 not occurringQuantification: ISTD: BDE 77, BDE 181 not occurring in technical mixtures; 13C12-labelled BDE-209
PBDEPBDEInterlaboratory studies on ISO Method
First interlaboratory study on PBDEs in 2000J de Boer and W P Cofino Chemosphere 46 (2002) 625-633J. de Boer and W. P. Cofino Chemosphere 46 (2002), 625 633
Results for the two sediment samples:
Congener RSD in % AssessmentBDE-47: 22/24 acceptableBDE-99: 36/45 further improvement necessary/ p yBDE-100: 20/20 acceptableBDE-153: 32/37 further improvement necessaryBDE-154: 35/45 further improvement necessaryBDE-209: 48/78 not under control
PAHPAH
Polycyclic aromatic hydrocarbons
AA-EQS:
Polycyclic aromatic hydrocarbons
z Anthracene 100 ng/Lz Fluoranthene 100 ng/Lz Fluoranthene 100 ng/Lz Benzo(a)pyrene 50 ng/Lz Benzo(b)fluoranthene+Benzo(k)fluoranthene 30 ng/L
z Benzo(g,h,i)perylene+ Indeno(1,2,3-cd)pyrene 2 ng/L
PAH: LOQ = from 0 6 ng/L to 16 ng/Lng/L to 16 ng/LPAH: LOQ = from 0. 6 ng/L to 16 ng/Lng/L to 16 ng/L
StatusPriority Substance Standard
Principle
Status
inland waters
other waters
Fluoranthene ISO 17993: 2002 HPLC/Fluo A A
ISO 17993:Naphthalene ISO 17993: 2002 HPLC/Fluo A A
EN ISO 15680:2003
Purge/Trap + Therm Desorp A A15680:2003 Therm. Desorp.
Benzo(a)pyrene ISO 17993: 2002 HPLC/Fluo C C
Benzo(b)fluoranthene4) ISO 17993: 2002 HPLC/Fluo C C
Benzo(k)fluoranthene4) ISO 17993: C CBenzo(k)fluoranthene4) 2002 HPLC/Fluo C C
Available Standard Method
EN ISO 17993: 2003Determination of 15 polycyclic aromatic hydrocarbons (PAH) p y y y ( )in water by HPLC with fluorescence detection after liquid-liquid extractionMatrix: Drinking, ground, waste and surface waterMatrix: Drinking, ground, waste and surface water
Method Descriptionhigh performance liquid chromatography (HPLC) with high performance liquid chromatography (HPLC) with fluorescence detection for the determination of 15 selected polycyclic aromatic.
Limit of Quantification (LOQ):Drinking and ground water: > 5 ng/L Surface water: > 10 ng/L
Oth A l ti l M th dOther Analytical Methods
EPA 8270c claims detection limit of 10 g/L EPA 8270c claims detection limit of 10 g/L which is obviously too high.
Other analytical methods based on this standard using modern GC/MS equipment however may tt i th i d l LOQ attain the required low LOQs.
R kRemarks
z The methods do not attain low enough LOQs and uncertainties for compliance checking with the AA-EQS for the sum of Benzo[b]fluoroanthene and Benzo[k]fluoroanthene as well as the sum of Benzo[g,h,i]perylene and Indeno[1,2,3-cd]pyrene.[g, , ]p y [ , , ]py
z In addition, not enough validation data are available di th l i f f t l i regarding the analysis of surface water samples in
particular samples containing substantial amounts of SPM.
z CEN Mandate for the development of analytical methods in progress!
Chemical Monitoring ActivityOn-Site WorkshopOn Site Workshop
Comparison of analytical approaches for WFD chemical monitoring: a field experimentg p
a JRC IES RWER Initiative
1st CMA On-Site Technical 1st CMA On-Site Technical Workshop
10-11 October 2006,in Ferrara Italyin Ferrara, Italy
River Po - Pontelagoscuro
2nd CMA On-Site Technical WorkshopWorkshop
17-18 September 2008in Budapest, Hungary
River Danube - Budapest
z Practical sampling exercise on the Po river;Sz Simultaneous bulk sampling by 8 teams with different methodologies(also from IWP Sofia BG);(also from IWP-Sofia-BG);
z Use of bulk sampling and shortterm integrating methods (large volume approaches);volume approaches);
z Homogeneity tests during exercise;
z Acquisition of accompanyingz Acquisition of accompanying data, as SPM, pH, temp.
CMAonsiteorganizedbyJRCIES(Ispra)andtheProvinceof( ) f h i l i fFerrara(Oct.2006)fortheimplementationofWFD.
7laboratoriesfrom7differentcountries Analytes:PBDEs,PAHs,nonylandoctylphenols 3samples
Standard extract water from the river :
Correspondingto14.6LofPoRiverwaterconcerningPBDEsandPAHs
d f f Correspondigto1LofwaterfromSevesoRiverconcerningalchilfenoli
S li d l i f P Ri SamplingandanalysisofPoRiver
AlkylphenolsCMA01 CMA03 CMA 06 CMA02 CMA05 CMA07 CMA04
Volume [L] 0.4 0.5 1.0 11.82 0.2 2.3 1.0 4150
Filtration no no yes yes yes no no n.a.
Extraction SPE SPE SPE Filtration SPE LLE SPE Centrifuge
SPE cart. /solvent
HLB 200 C18 C18 Randallextraction
HLB 60 DCM EnvichromP
Soxhlet
SPE elution EA MeOH +MTBE
Acetone SPM DCM/EA n.a. DCM SPM
Analytical LC-MS (tq) LC-MS (tq) LC-fluor LC-fluor GC-MS GC-MS GC-MS GC-MS (it)methodLC solvents H2O-ACN H2O-ACN H2O-MeOH H2O-MeOH n.a. n.a. n.a. n.a.
Column C18 C18 Phenylhexyl Phenylhexyl DB-5 DB-5 DB-1 ZB-5
Length 2.1150mm 2.1 100 mm 4.6250 mm 4.6 x 250 mm 30 m 30 m 60 m 30 m
Deriv. n.a. n.a. no no no no no MSTFA
Ions orwavelengthmonitored
219 > 133227 > 112205 > 106205 > 133
219 > 133219 > 106225 > 112205 > 133
230 nm exc.302 nm em
230 nm exc.302 nm em
149(for NP)135(forOP)121107
135 1351075722077
207 > 179221 > 179235 > 179278 > 179292 > 179107 77 292 > 179
IST 4n-NP d8 4n-NP d6 no no 4n-NP d8 4n-NPd8
Atrazine d5 4-Bromophenol
Alkylphenolsstandard solutionstandard solution
300
NPLC-FL
200
250
NP
n-OPLC-MSGC-MS
GC-MS
LC FL
150
200
n
g
/
m
L
GC-MS
100
n
LC-MS
0
50
CMA00 CMA01 CMA02 CMA03 CMA04 CMA05 CMA06 CMA07
RSD 5 labs 23-29%
AlkylphenolsRiver Seveso extractRiver Seveso extract
1200
1000 NPtert-OP
LC-MS
GC-MS
600
800
/
m
L
GC-MS GC-MSLC-FL
400
600
n
g
/
LC MS200
LC-MS
0
CMA00 CMA01 CMA02 CMA03 CMA04 CMA05 CMA06 CMA07
RSD 5 labs % 29 (NP)
AlkylphenolsAlkylphenolsriver Poriver Po
120 GC-MS
80
100
LC-MS LC-FL
60
80
n
g
/
L
GC MS40
< 22
LC-MS
GC-MS
GC-MS
GC-MS
0
20 < 10< 105.1
CMA00 CMA01 CMA02 CMA03 CMA04 CMA05 CMA06 CMA07
CMA on site field intercomparison:CMA on-site field intercomparison:PAH in river water
Methods used:CMA00: SPE- LC/MS/MS/ /CMA01: LLE-GC/MSCMA02: SPE-GC/MSCMA02: SPE GC/MSCMA03: LLE-GC/MSCMA04: ASE-GC/MS (only SPM)CMA04: ASE GC/MS (only SPM)CMA05: LLE-GC/MSCMA06: SPE-GC/MSCMA06: SPE GC/MSCMA07: SPE-GC/MS
CMA on-site field intercomparison:
CMA00 CMA01 CMA02 CMA03
PAH in river water
20.00
22.00
CMA00 CMA01 CMA02 CMA03CMA04 CMA05 CMA06 CMA07
89
14.00
16.00
18.00 value below LOQ
8.00
10.00
12.00
[
n
g
/
L
]
2.00
4.00
6.00
0.00
Anthr
acen
e
Fluora
nthen
e
zo(a)
pyren
e
)fluora
nthen
e
h,i)pe
rylen
e
2 3-cd
)pyren
e
A Fl
Benz
Benz
o(b+j+
k)fl
Benz
o(g,h
Inden
o(1,2,
3
Po river: PAH sum whole water results(SPM = 45 mg/L)
LLE40
1
3
5
30SPEEDISK
WITHOUT
/
L
SPECENTRIFUGE
SPM
AVERAGE OF 5
REFERENCE
20 SPEWITH
FILTRATION FILTR + LLE SPM+DISS
FILTRATION
n
g
/
LLEWITHOUT
FILTRATION
< 10 < 10
METHODS
SPM+DISS
10 DISSSPM+DISS
0CMA00 CMA01 CMA02 CMA03 CMA04 CMA05 CMA06 CMA07
Grey bars are the blank value determined LOQs of the labs.
CMA on site field intercomparison:CMA on-site field intercomparison:PBDE in river water
Methods used:CMA00: SPE- GC/MS/MS/ /CMA03: LLE-GC/MSCMA04: ASE-GC/MS (only SPM)CMA04: ASE GC/MS (only SPM)CMA05: LLE-GC/MSCMA06: SPE-GC/MSCMA06: SPE GC/MS
CMA on-site field intercomparison:CMA on site field intercomparison:
PBDE in river water
0.5
0.3
0.4
L
]
CMA00CMA03CMA04
0.2
[
n
g
/
L CMA05CMA06
0
0.1
0BDE-28 BDE-47 BDE-99 BDE-100 BDE-153 BDE-154
Po river: PBDE sum whole water results(SPM 45 /L)(SPM = 45 mg/L)
1 FILTR + LLE
0.8
1 SPM+DISS
0.6
L
]
SPEEDISK
WITHOUT FILTRATION
AVERAGE OF 5
REFERENCE
0.4[n
g
/
L
REFERENCE METHODS
SPM+DISSFILTR + LLECENTRIFUGE
0.2
FILTR + LLE SPM+DISS
CENTRIFUGE
SPM
0CMA00 CMA03 CMA04 CMA05 CMA06
Total PBDEsResults for river Po
2,5
3
3,5water expressed as total concentrations (ng/L)
1
1,5
2Grey bars are < LOD
0
0,5
Total PAHs
Conclusion:Further work is needed to develop suitable and
robust methods for PS monitoring in natural surface
120140160
Total PAHs
Total alkylphenols
robust methods for PS monitoring in natural surface waters and harmonise labs at EC level
6080
100120
80
100
120
02040
CMA00 CMA01 CMA02 CMA03 CMA04 CMA05 CMA06 CMA07 20
40
60
0
20
CMA00 CMA01 CMA02 CMA03 CMA04 CMA05 CMA06 CMA07
Participant
POLYCHLOROALKANES C to C Challenges 1POLYCHLOROALKANES C10 to C13 Challenges 1
) Complex mixture of many thousands of positional isomers6304 positional isomers assuming no more than one bound chlorine atom on any carbon atomatom on any carbon atom
) Incomplete chromatographic separationgas chromatograms of short chain PCAs show broad humps covering
) Lack of specificity when using GC ECNI MS at standard ion
gas chromatograms of short-chain PCAs show broad humps covering 10 to 15 minutes
) Lack of specificity when using GC-ECNI-MS at standard ion source operating conditions Monitoring of less charcteristic m/z = 70-73 ions (Cl2-; HCl2-)
POLYCHLOROALKANES C10 to C13 Challenges 2
) Lack of specificity when using GC-ECNI-MS detection at nominal mass
t ti l i t f f PCB t h d hl d l t d
) Lack of appropriate calibration standardspotential interferences from PCBs, toxaphenes, and chlordane related compounds
Lack of appropriate calibration standardsDepending on the degree of chlorination of the calibration standard results can differ from by a factor of ten
POLYCHOROALKANES C10 to C13 Methods10 13
) Dehydrochlorination of the PCAs and subsequent determination of the resulting aliphatic hydrocarbons
) Gas chromatography with electron impact ionisation mass spectrometric detection (GC-MS)
) Gas chromatography with electron capture negative ionisation mass spectrometric detection at high resolution (GC-ECNI-HRMS)
) Gas chromatography with electron capture negative ionisation mass spectrometric detection at low
resolution (GC-ECNI-HRMS)
ionisation mass spectrometric detection at low resolution (GC-ECNI-MS)
POLYCHLOROALKANES C10 to C13I t l b t t dInterlaboratory study
First interlaboratory study on PCAs in 1998G. T. Tomy et al. Analytical Chemistry 71 (1999), 446-451
Results:) Seven laboratories ) Two PCA solutions, two fish extracts, PCA-60 commercial
formulation of stated concentration) In case of the two PCA solutions deviations from of up to 74
and 310 %, respectively, were observed) Fish sample1 (only three results) RSD = 27%) Fish sample 2 RSD = 47%Conclusion:Conclusion:
) Analysis of PCAs is not under control
POLYCHLOROALKANES C10 to C13 StandardisationPOLYCHLOROALKANES C10 to C13 Standardisation
) Analysis of short-chain PCAs is just on the research level at the momenton the research level at the moment
) EC gives a mandate to CEN for developing a suitable method
Recommended