Miljø- og Fødevareudvalget 2021-22
MOF Alm.del Bilag 717
Offentligt
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HITLIST4
Non-targeted and
suspect screening of
sewage sludge
[Serietype og nummer]
August 2022
MOF, Alm.del - 2021-22 - Bilag 717: Orientering om resultaterne af projekt om undersøgelse af miljøfarlige forurenende stoffer i slam
Publisher: The Danish Environmental Protection Agency
Editors: Martin Hansen, Mulatu Y. Nanusha, Emil Egede Frøkjær, Martin Mørk Larsen &
Jens Søndergaard
This scientific report has been reviewed by four Steering Group Members from the Danish
Environmental Protection Agency: Maj-Britt Bjergager, Ida Rasmussen, Jakob Bruun Nico-
laisen and Helle Rüsz Hansen.
Graphics: Department of Environmental Science, Aarhus University
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Contents
Abstract
Acronyms
1.
2.
2.1
2.2
2.3
2.4
3.
3.1
3.2
3.3
3.4
3.5
4.
5.
Introduction
Methodology
Sewage sludge samples
Analytical platforms
Sample preparation
Data analysis
Results and discussion
Inorganic elements
NTS dataset
Identified organic substances
Suspects
Multivariate data analysis and data exploration
Conclusion
References
Sample overview
Methods
Internal standards
ICP-MS dataset
NTS dataset
4
5
6
7
7
7
7
7
9
9
12
12
13
15
17
18
19
20
26
30
31
Appendix 1.
Appendix 2.
Appendix 3.
Appendix 4.
Appendix 5.
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Abstract
This project applied non-targeted and suspect screening to activated sludge from five Danish
wastewater facilities. In addition, the concentrations of 61 elements were also determined in
the sludge.
The sludge concentrations showed relatively high levels of mercury (0.4-1.4 mg/kg) and
cadmium (0.4-1.4 mg/kg), compared to natural levels in arable soils. Also, a high copper (203-
571 mg/kg) and zinc (502-1616 mg/kg) concentrations in sludge relative to arable soil show
that the use of sludge is likely to increase the level of copper and zinc over time in sludge
amended fields.
Five non-targeted screening platforms were applied to analyse the sewage sludge. After
data analysis, thousands of substances were discovered in the non-targeted dataset. Search-
ing the data against in-house and international databases 41 substances were determined at
the highest annotation level (1), 1,751 molecules were identified at the second highest level
(2), 7,091compounds at level 3, and a total of 15,471 combined at level four and five. Exam-
ples of confirmed substances are 1H-benzotriazole, 2,6-dichlorophenol, bisphenol S,
methylparaben, terbutryn and prosulfocarb.
By applying novel semi-quantitative concepts, it was possible to predict concentrations of
513 substances, e.g. PFOS was detected at all five sites with concentrations ranging from 2.4-
47.4 µg/kg sludge, while 6PPD-quinone was only found in three sites (14-74 µg/kg). Endoge-
nous or natural metabolites were found, e.g. bile acids as deoxycholate (58-3247 µg/kg) and
peptides as Gly-Leu-Lys (53-938 µg/kg).
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Acronyms
dw
EI
ESI
GC
HLB
HRMS
ICP-MS
LC
LOD
MFS
MS
nLC
NTS
PFAS
PFCs
ppb
ppm
QC
SPE
Dry weight
Electron impact ionization (GC)
(Heated) electrospray ionisation (LC)
Gas chromatography
Hydrophilic-lipophilic balanced polymer
High-resolution mass spectrometry
Inductively coupled plasma mass spectrometry
Liquid chromatography
Limit of detection
Miljøfarlige stoffer (substances of emerging concern)
Mass spectrometry
nano-liquid chromatography
Non-targeted screening analysis
Per- and polyfluoroalkyl substance
Perfluorochemicals
Parts-per-billion (ng/mL, µg/L)
Parts-per-million (µg/mL, mg/L)
Quality control
Solid phase extraction
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1. Introduction
Sewage sludge is rich in nutrients and can be applied to agricultural soils (BEK nr 1001 af
27/06/2018). However, sludge may also contain elevated levels of contaminants such as heavy
metals that can have adverse effects on the environment and pose a health risk for human
consumption of the agricultural produce. Organic micropollutants, or substances of environmen-
tal concern (termed MFS in Danish) is another category of contaminants that may enter the
environment via agricultural sludge amendment to exert unwanted public and environmental
health side-effects.
Recently, it was demonstrated that, holistic non-targeted screening analysis (NTS) provides
the means to perform mass suspect screening and go beyond to discover previously unknown
molecular entities in environmental samples. NTS is revolutionary and fundamentally different
from targeted monitoring strategies and has a large potential for effective evaluation of water
quality regulations. NTS is based on high-resolution mass spectrometry (HRMS), that rapidly
profile thousands of (unknown) substances in complex environmental samples [1]–[3]. The NTS
strategy is used when former unknown compounds are detected in a sample and data is inves-
tigated without any presumptions or knowledge of the sample [4]. Suspect screening is another
strategy used for searching HRMS data for known chemicals, i.e. by using a reference list of
pesticides and biocides which are expected to be present in the sample [4]. As such, NTS is
used to describe this entire field of research.
The NTS concept was recently developed and applied in a research project (HITLIST1) un-
der the Danish Environmental Protection Agency’s Pesticide Research Program [1]. The work
was followed by a recent Danish EPA research project (HITLIST2) that mapped the detectable
chemical space and further validated the NTS methodology, so it can be used as a reliable
monitoring method for the NOVANA water quality program. Finally, a third research report is
currently under review (HITLIST3) on applying the NTS concept on Danish surface water sam-
ples.
The aim of the present project ‘HITLIST4’ was to apply NTS and ICP-MS methodologies to
determine inorganic and organic micropollutants in sewage sludge. A secondary objective was
to compile a list of substances identified at each location, make concentration estimations based
on novel semi-quantitative approaches and use multivariate statistics for in-depth data explora-
tion.
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2. Methodology
2.1
Sewage sludge samples
A total of five facilities provided activated sludge samples in November and December 2021
(Table 1). In all cases sludge were stored in anaerobic digesters following by dewatering. All
sludges are approved for use on agricultural soils (grade A).
Table 1.
Overview of studied wastewater sludge samples and facility details. PE, actual per-
son equivalents burden.
Facility
Type
PE
Digestion
Roskilde
Måløv
Ejby Mølle
Egå
Herning
Biodenipho
Biodenipho
Biodenipho
Biodenipho (modified)
Biodenipho
125.000
70.000
225.000
90.000
150.000
3 weeks anaerobic digestion
3-4 weeks anaerobic digestion
4 weeks anaerobic digestion
3 weeks anaerobic digestion
Thermophilic digestion (2 weeks) fol-
lowed by mesophilic digestion (2
weeks)
2.2
Analytical platforms
Five high-resolution mass spectrometry NTS analytical platforms were used to analyse the sam-
ples for organic micropollutants. In addition, an accredited inductively coupled plasma mass
spectrometry (ICP-MS) methodology was used to determine concentrations of 61 inorganic el-
ements in the sludge. The five NTS platforms were reverse-phase nano-liquid chromatography
electrospray ionisation high-resolution tandem mass spectrometry (nLC-ESI-HRMS/MS in pos-
itive and negative ionisation modes), cap-flow cLC-ESI-HRMS/MS methods (in positive and neg-
ative ionization mode) directed towards detecting e.g. perfluorochemicals and gas chromatog-
raphy electron impact ionisation high-resolution mass spectrometry (GC-EI-HRMS) and are fur-
ther detailed in Appendix 2.
1)
2)
3)
4)
5)
6)
nLC-ESI(+)-HRMS/MS
nLC-ESI(-)-HRMS/MS
cLC-ESI(+)-HRMS/MS
cLC-ESI(-)-HRMS/MS
GC-EI(+)-HRMS
ICP-MS
2.3
Sample preparation
Samples were collected in Rilsan bags and immediately stored in cooler box (5
o
C) and trans-
ported to the analytical lab and stored at -20
o
C. Sample aliquots of 0.20 grams for inorganic
element analysis were acid extracted using microwave extraction and analysed by ICP-MS ac-
cording to EPA method 3051A. Sample aliquots of 0.20 grams for organic micropollutant analy-
sis were spiked with isotope-enriched internal standards and extracted using pressurized liquid
extraction in a two-way workflow (one for LC and another for GC). Sample extracts for GC-
HRMS workflows were analysed directly, while extracts for LC-HRMS workflows were further
purified using solid-phase extraction (for details see Appendix 2).
2.4
Data analysis
The LC and GC-HRMS raw data were processed using Compound Discoverer 3.3 (Thermo
Fisher) for peak detection, retention time alignment and peak picking for non-target screening.
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An overview of the Compound Discoverer and non-target data processing workflow can be
found in (Appendix 2.6). The output of this is a feature list, i.e. a table with m/z and retention
time pairs (features) and their peak area, which were further processed for the identification and
structural elucidation of contaminants. The detected peaks were prioritized based on the criteria
such as peak intensity threshold, blank subtraction, reasonable peak symmetry (sharp peak
apex), molecular formula predicted from the exact mass and the isotopic pattern as well as
structural similarity match with the analytical reference standard. The data analysis filtration and
decision tree(s) are available in detail in Appendix 2.7. The features/compounds were confirmed
to different identification levels (level 1 to 5) as suggested by Schymanski et al. [5]. In short, a
level 1 substance has been confirmed by a reference standard on the same NTS platform (MS,
MS/MS and retention time matching). A level 2 substance is a highly probable structure matched
to literature and/or public MS/MS spectral libraries, and may further be supported by retention
time predictions. A level 3 substance is tentative candidate structure where no MS/MS libraries
exist, however the experimental evidence is supported by in silico MS/MS fragmentation predic-
tions. A level 4 substances is when an unequivocal chemical formula can be assigned from MS
spectral data (e.g. adduct, isotopic pattern). A level 5 substance is when only the exact mass
(m/z) can be assigned. Concentrations of level 1 and 2 identified substances were performed
by novel semi-quantitative approaches [6], and are described in detail in Appendix 2.8. Statistical
analyses were performed using GraphPad Prism 9.3 and MetaboAnalyst 5.0.
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3. Results and discussion
3.1
Inorganic elements
The ICP-MS analyses included screening of 61 elements of the five sludge samples (Figure
1). Specific element concentrations across the five sites were relatively similar, e.g. arsenic
(As) varied from 2.99 in Roskilde to 8.26 mg/kg dw in Ejby Mølle and mercury (Hg) from 0.41
in Ejby Mølle to 1.41 mg/kg dw in Måløv. Iron (Fe) was observed in the highest concentration
(46.2 g/kg dw in Måløv), while rhenium (Re) was found at the lowest levels (0.002 mg/kg dw in
Ejby Mølle and Måløv). A complete and detailed dataset of all 61 elements is available in Ap-
pendix 4.
Figure 1.
Concentrations of 61 inorganic elements in wastewater activated sludge (mg/kg dry
weight) determined with ICP-MS.
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A comparison with limit values in BEK nr 1001 of 27/06/2018 for inorganic elements in waste
applied for agricultural or private gardens use are compiled in Table 2. As shown, all five
sludge samples comply with the safety limit values. The limit values expressed on a dry weight
basis were exceeded for cadmium and/or mercury (and just exceeded for nickel) in three of
the samples but were below the limit value expressed per amount phosphorus. According to
BEK nr. 1001, the waste must comply with the limit values expressed on either dry weight ba-
sis or phosphorus basis, so all samples comply with this criterion. However, the results indi-
cate that the metals of particular concern in the waste are cadmium and mercury, which
should be monitored closely especially if large amounts of waste are spread or if a significant
variation in composition is expected.
Comparison with average levels from 430 samples of arable soil [7] in 1992 and 1993 indicate
levels in the sludge is within a factor of two for arsenic, between 1.4 and 7 times higher for
cadmium, chromium, nickel and lead, whereas mercury is a factor of 8-28 times higher in
sludge than in arable soil. Copper and zinc are used in many household products and leaks
from plumbing, so levels are 17-73 times higher in sludge than arable soils. It has been ar-
gued, that the sludge amendment leads to increasing levels of copper and zinc in arable land
topsoil (0-25 cm) of respectively 0.16 and 0.96 mg/kg/y, or 1.7 and 3% increase per year from
1998 to 2014, and slightly less below the ploughing zone (25-50 cm) at 1.6 and 2.8% increase
per year [8].
Compared to the levels in the Earth’s Crust particularly bismuth and gold are concentrated
in the sludge samples (270-610 resp. 45-110 times above Earth Crust levels), but also anti-
mony, selenium, phosphorous, silver, zinc, mercury and platinum are present in up to 10-40
times the level in the earth crust (in declining order). Bismuth present at very low levels in the
Earth Crust (around 0.009 mg/kg), but is used both for medicine, in personal care products, as
a catalyst for rubber and fibers, in alloys and have been used in shot and bullets as replace-
ment for lead. The use of gold in electronics, medical treatments and nano-gold are potential
sources for the sludge. Antimony is also used in electronics, as alloys (mainly with lead), and
antimony compounds are used for flame-retardant materials, paints, glass and pottery. Sele-
nium is used as additive to glass and in photocells, solar cells and photocopiers, it is toxic and
used in anti-dandruff shampoos, but it is also an essential element needed in small amounts,
with both carcinogenic and teratogenic effects at raised levels. Silver is used in jewelry and
utensils, in mirrors and solder, electrical contacts and batteries. It was previously used in pho-
tography, and now as antibacterial nano-particles in e.g. clothes, foot ware and touchscreen-
enabled gloves. Platinum is also used for jewelry, but today mainly as catalytic converters for
cars, trucks and busses. Also, other industrial catalytically uses, in electronics including optical
fibers and LCDs, and in chemotherapy drugs. All uses are cited from the Royal Society of
Chemistry [9]. The high ratio metals can mostly be attributed to industrial, therapeutic or
household product use of rare metals or metalloids, whereas the more ordinary elements like
phosphor and zinc are used in large quantities by households, farmers and industry to give the
overrepresentation in sludge. Mercury is supposed to be more or less banned, and the high
levels in sludge are mainly attributed to legacy usage. In Europe it is probably mainly used in
fluorescence lighting, the majority is from long range transport from artisan goldmining in Af-
rica, together with pollution from coal burning in powerplants in Eastern Europe and Asia.
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Table 2.
Limit values of inorganic elements in waste for agricultural use and private gardens in
BEK no. 1001 of 27/06/2018 in comparison to measured values in the five sludge samples.
The sludge must comply with either the limit value for an element in mg kg
-1
dry weight or the
limit value in mg kg
-1
total phosphorus (P). Limit values for inorganic elements in soil in BEK no
1001 and the average concentrations in Danish soils are listed in the bottom of the table for
comparison. A detailed table is available in Appendix 4.
Concentrations in mg kg
-1
dry weight
Cr
Safety limit values for
waste used for agricul-
ture (BEK no. 1001,
27/06/2018)
Safety limit values for
waste used for private
gardens (BEK no.
1001, 27/06/2018)
N001 Roskilde (n=2)
N004 Ejby Mølle
N007 Egå
N010 Måløv
N013 Herning (n=2)
Safety limit values for
soil (BEK no. 1001,
27/06/2018)
Average soil level
1992/3 N=430 (Larsen
et al, 1996)
Ni
Cu
Zn
As
Cd
Hg
Pb
Concentrations in mg kg
-1
total P
Ni
Cd
Hg
Pb
100
30
1000
4000
-
0.8
0.8
120
2500
100
200
10000
100
57
20
23
47
68
30
19
10
14
19
31
1000
335
203
348
571
214
4000
926
502
693
736
1616
25
3
8
6
6
8
0.8
1.4
0.4
0.8
0.7
1.1
0.8
1.0
0.4
0.6
1.4
0.6
60
38
18
17
18
35
2500
605
363
410
556
1061
100
44
15
23
20
37
200
31
14
18
42
22
5000
1235
640
491
550
1228
30
15
40
100
0.5
0.5
30
12
6
8
30
4
0.2
0.05
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3.2
NTS dataset
After data analysis pipelines were applied (Appendix 2.6) to the NTS HRMS dataset (LC and
GC), nearly half a million features were observed, and they could be grouped into thousands of
substances. After lab procedural blank background filtration, the GC EI dataset was assembled
into
c.
2,300 substances whereas 1,056 substances were annotated at level 2, 189 compounds
at level 3 and 1027 compounds at level 5. The combined LC datasets contained over 20,000
features across both positive and negative ionization modes. Nearly 15,000 of these could only
be annotated as either m/z or as a calculated chemical formula (levels 5 and 4 respectively).
6,902 compounds (not taking duplicates into account) were annotated at level 3 across both
platforms, i.e. with proposed chemical structure based on MS2 fragments. A total of 725 unique
compounds were identified at level 2 across both platforms, with 546 detected in positive mode,
215 in negative mode, and 36 compounds detected in both platforms. 29 compounds were de-
tected at level 1 using positive ionization and 15 using negative, with a combined total of 41
unique level 1 compounds across the two platforms (LC negative and LC positive).
The current state-of-the-art semi-quantitative methods can predict concentrations of LC (ESI)
data, however not GC (EI) data and more research efforts are urgently needed in this area.
3.3
Identified organic substances
The identity of 41 substances were confirmed (level 1) across the dataset (Table 2). See Ap-
pendix 2.8 for a detailed description of data curation for level 1 annotation. The complete dataset
with level 1-5 annotations is available through Appendix 5.
Table 3.
Substances identified at the highest level (1) with observed minimum and maximum
sludge concentrations (across all identified platforms) and detection frequencies (D
f
). n.c. de-
noted concentration not calculated by the semi-quantitation algorithm.
Name
C
min
(µg/kg)
Industrial substances
1H-Benzotriazole
4-Methyl-1H-benzotriazole
5-Methyl-1H-benzotriazole
Bisphenol S
Dimethyl phthalate
Ethylparaben
Methylparaben
Tributyl phosphate
Triisobutyl phosphate
Tris(2-butoxyethyl) phosphate
Vanillin
57
204
31
25
189
287
287
93
n.c.
127
639
Pesticides and biocides
2,6-Dichlorophenol
Clomazone
Prosulfocarb
Terbutryn
n.c.
n.c.
81
73
Pharmaceuticals
Aspartame
Azithromycin
Caffeine
Carbamazepine
90
11
103
n.c.
685
2807
9075
n.c.
60
40
40
100
n.c.
n.c.
305
654
40
40
60
60
3283
617
1577
116
964
952
952
343
n.c.
750
17431
100
100
100
60
80
100
100
100
100
40
100
C
max
(µg/kg)
D
f
(%)
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Cetirizine
Citalopram
Cotinine
Fexofenadine
Furosemide
Lamotrigine
Losartan
Metoprolol
Miconazole
Nicotine
Propranolol
Salicylic acid
Sertraline
Venlafaxine
Diclofenac
Ibuprofen
16
114
n.c.
17
31
n.c.
69
82
n.c.
104
19
99
9
4
4
15
Natural products
52
1120
n.c.
189
85
n.c.
496
1020
n.c.
809
449
4048
362
599
70
90
80
80
60
100
100
80
100
80
60
60
80
100
100
100
100
80
Daidzein
Genistein
19
42
PFAS substances
2962
70
80
20
Perfluorodecanoic acid (PFDA)
Perfluorooctanesulfonic acid (PFOS)
Perfluorononanoic acid (PFNA)
Perfluorooctanesulfonamide (PFOSA)
2
3
1
1
11
53
2
3
100
100
60
40
3.4
Suspects
A list of suspects was used for screening throughout the dataset. The combined dataset also
revealed the tyre residues 6PPD and 6PPD-quinone were present in sludge samples. The two
substances were detected using two platforms, i.e. demonstrating the importance of combining
NTS platforms to obtain a more complete chemical fingerprint.
It is expected the applied NTS platforms will be able to detect all listed suspects of interest
(Table 3), however substances could be present below detection limits or hampered by matrix
interference. Some substances are identified to level 2 as no in-house reference standard was
available. Other substances as level 3 (tentative candidates), as the obtained MS/MS-frag-
mentation spectral score was low.
Table 4.
Suspects extracted from the NTS dataset.
Compound name
Industrial substances
6PPD
6PPD-Quinone
1,2,4-Triazole
Pesticides and biocides
Trimethoprim
Pyrethrin
Cypermethrin
Yes
Yes
No
3
2
Yes
Yes
No
2
2
Found
Annotation level
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Permethrin
Deltamethrin
Lamda-cyhalothrin
Spinosad A
Pharmaceuticals
beta-Estradiol
(+)-Estrone
Azithromycin
Citalopram
Clarithromycin
Diclofenac
(-)-Erythromycin
Naproxen
Ibuprofen
2-hydroxyibuprofen
Propranolol
Tramadol
Carbamazepine
Telmisartan
Metformin
Metoprolol
Sertraline
Ciprofloxacin
Venlafaxine
PFAS substances
Trifluoroacetic acid
Heptafluorobutyric acid (PFBA)
Perfluoropentanoic acid (PFPeA)
Perfluorohexanoic acid (PFHxA)
Perfluoroheptanoic acid (PFHpA)
Perfluorooctanoic acid (PFOA)
Perfluorononanoic acid (PFNA)
Perfluorodecanoic acid (PFDA)
Perfluorododecanoic acid (PFDoA)
Perfluorotridecanoic acid (PFTrDA)
Perfluorobutanesulfonic acid (PFBS)
Perfluorohexanesulfonic acid (PFHxS)
Perfluoroheptanesulfonic acid (PFHpS)
Perfluorooctanesulfonic acid (PFOS)
Perfluorodecanesulfonic acid (PFDS)
Perfluorooctanesulfonamide (PFOSA)
6:2 FTSA (1h,1h,2h,2h-perfluorooctanesulfonic acid)
No
No
No
No
Yes
Yes
Yes
Yes
Yes
Yes
Yes
No
Yes
Yes
Yes
Yes
Yes
Yes
No
Yes
Yes
No
Yes
2
3
1
1
2
1
2
2
1
1
3
1
2
1
1
1
No
No
No
No
No
No
Yes
Yes
Yes
No
No
No
No
Yes
No
Yes
No
1
1
1
1
3
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3.5
Multivariate data analysis and data exploration
The analysed NTS data revealed very different molecular fingerprints between wastewater treat-
ment plants (Figure 2). Clearly, the sewage sludge samples fall into three groups having very
similar molecular signatures; Zealand (Roskilde, N01-02 and Måløv, N10-12); Fuenen (Ejby
Mølle, N04-06) and Jutland (Egå, N07-09 and Herning, N13-15).
Figure 2:
Scores (red) and loadings (blue) in biplot using multivariate principal component anal-
ysis is used for data exploration of the samples (red) and concentrations of 513 substances
(blue). Samples clustered in proximity to each other has very similar chemical profiles, whereas
samples far from each other are very dissimilar. Substances in proximity with specific samples
are highly associated with its occurrence at this site. For simplicity substances has been num-
bered from 1-513 and table with substance names are found in Appendix 5.
Evidently, some chemicals are highly associated with sewage sludge from specific sites. E.g.
the industrial chemical 1-Methyl-1H-benzotriazole (substance no. 74 in proximity to sample
N10) is in high abundance in Roskilde and Måløv sludges (305-504 µg/kg), yet still occurring in
the Herning sludge, albeit at lower concentrations (140-181 µg/kg, Appendix 5). Some chemi-
cals are common across the samples and located at the centre region of the PCA biplot, e.g.
Mono(2-ethylhexyl) phthalate (MEHP, substance no. 402 and is present in all samples at simi-
lar levels; 20-57 µg/kg, Appendix 5).
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2622966_0016.png
Figure 3:
Scores and loadings plot in multivariate principal component analysis is used for data
exploration of the samples analysed in GC EI dataset. Each sample is displayed in the scores
plot (left). Samples clustered in proximity to each other has very similar chemical profiles,
whereas samples far from each other are very dissimilar. The loadings plot (right) displays every
detected substance present in the given dataset (1,056 substances annotated at level 2 for GC
IE). Overlaying the two plots the association between substance and sample is visualised. One
sample (Roskilde) were omitted as outlier.
Figure 4:
Differential analysis between Herning and Ejby Mølle for GC-EI dataset. Each dot is
a substance and analysis are performed with n=3 for each group. Substances on left side (blue
area) is in higher abundance in Herning when compared to Ejby Mølle. Substances on right side
(red area) is in lower abundance in Herning when compared to Ejby Mølle. The higher (vertical
y-axis) adjusted -log p value to more significant. 238 substances (blue) are at significantly higher
abundance in Herning and another 227 substances (ren) are significantly higher abundance in
Ejby Mølle, while 168 substances (grey) are not significantly different in abundance between the
two sites. One of the encircled substances (red ring) is sertraline (GC-2103, see Appendix 5 for
substance names).
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4. Conclusion
In terms of inorganic elements, all sludge samples complied with the criterion in the current BEK
no. 1001 on waste applied for agriculture. The metals causing most concern in sludge are rela-
tively high levels of mercury and cadmium, compared to natural levels in arable soils. But also
interesting to see the high levels of particular rare metals as bismuth and antimony, and precious
metals like gold, silver and platinum, all of which with many uses in both industry, as catalysts
and alloys, as therapeutic products in hospitals and in house hold products like jewellery, elec-
tronics, nano-particles in clothes and cosmetic products. The high copper and zinc concentra-
tions in sludge relative to arable soil show that the use of sludge is likely to increase the level of
copper and zinc over time in sludge amended fields, both in the top soil and below the ploughing
zone.
The NTS dataset revealed that a great number of micropollutants are present in waster sludge
and the chemical fingerprint varies across wastewater sites. Combined with suspect screening
and semi-quantitative concentration determinations it was possible to estimate sludge concen-
trations of more than 500 chemicals. To name a few substances observed at all sites, diclo-
fenac with concentrations ranging 4-70 µg/kg, ethylparaben (287-953 µg/kg), perfluorodeca-
noic acid (PFDA, 2-11 µg/kg), azithromycin (11-2807 µg/kg) and tributyl phosphate (93-343
µg/kg). The chemical identity and occurrence were very different between sites, exemplified by
the herbicide prosulfocarb observed at three out five sites at 61-305 µg/kg. Several parent
chemicals and associated metabolites were also observed, such as venlafaxine and O-
desmethyl-venlafaxine. The dataset also revealed five different per- and polyfluoroalkyl sub-
stances are present in sewage sludge. Especially, PFOS and PFDA were omnipresent and
detected in all samples at 2-53 µg/kg.
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5. References
[1]
[2]
“Danish EPA pesticide and biocide research programme, project: HITLIST, grant no.
MST-667-00207, project period: June 2018 to December 2019.”
T. K. O. Gravert, J. Vuaille, J. Magid, and M. Hansen, “Non-target analysis of organic
waste amended agricultural soils: Characterisation of added organic pollution.,” Under
review, 2021.
N. L. Ma
et al.,
“Body mass, mercury exposure, biochemistry and untargeted
metabolomics of incubating common eiders (Somateria mollissima) in three Baltic
colonies,”
Environ. Int.,
vol. 142, no. January, p. 105866, 2020.
J. R. Sobus
et al.,
“Integrating tools for non-targeted analysis research and chemical
safety evaluations at the US EPA,”
J. Expo. Sci. Environ. Epidemiol.,
vol. 28, no. 5, pp.
411–426, 2018.
E. L. Schymanski
et al.,
“Identifying small molecules via high resolution mass
spectrometry: Communicating confidence,”
Environmental Science and Technology,
vol. 48, no. 4. pp. 2097–2098, 2014.
J. Liigand, T. Wang, J. Kellogg, J. Smedsgaard, N. Cech, and A. Kruve,
“Quantification for non-targeted LC/MS screening without standard substances,”
Sci.
Rep.,
vol. 10, no. 1, p. 5808, Dec. 2020.
M. M. Larsen, J. Bak, and J. Scott-Fordsmand, “Monitering af tungmetaller i danske
dyrknings- og naturjorde : Prøvetagning i 1992/93.”
J. Jensen, M. M. Larsen, and J. Bak, “National monitoring study in Denmark finds
increased and critical levels of copper and zinc in arable soils fertilized with pig slurry
*,”
Environ. Pollut.,
vol. 214, pp. 334–340, 2016.
“Royal Society of Chemistry.” .
J. P. Koelmel
et al.,
“Acquisition With Automated Exclusion List Generation,”
J Am Soc
Mass Spectrom.,
vol. 28, no. 5, pp. 908–917, 2018.
A. Schlosser and R. Volkmer-Engert, “Volatile polydimethylcyclosiloxanes in the
ambient laboratory air identified as source of extreme background signals in
nanoelectrospray mass spectrometry,”
J. Mass Spectrom.,
vol. 38, no. 5, pp. 523–525,
2003.
J. V. Olsen
et al.,
“Parts per million mass accuracy on an orbitrap mass spectrometer
via lock mass injection into a C-trap,”
Mol. Cell. Proteomics,
2005.
[3]
[4]
[5]
[6]
[7]
[8]
[9]
[10]
[11]
[12]
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2622966_0019.png
Appendix 1.
Sample overview
Table 5.
Overview of sludge samples and locations. The legends/names used in data analysis
are underlined.
Site
FORS Roskilde Spildevand A/S
Vandcenter Syd, Ejby Mølle
Århus vand, Egå renseanlæg
Novafos Måløv Renseanlæg
Herning Vand
Sample ID (n)
N001, N002, N003
N004, N005, N006
N007, N008, N009
N010, N011, N012
N013, N014, N015
Sampling date
November 24, 2021
December 14, 2021
December 14, 2021
December 13, 2021
December 14, 2021
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Appendix 2.
Appendix 2.1
Methods
Liquid chromatography high-resolution mass spectrometry
This system was used for two NTS platforms (nLC-ESI(+)-HRMS/MS and nLC-ESI(-)-
HRMS/MS). Nano-liquid chromatographic separation was performed on a Dionex Ultimate 3000
NCS-3500RS Nano Proflow system (Thermo Scientific). Ready samples were stored in glass
96-well plates in a Dionex WPS-3000 TPL RS autosampler at 8°C. Sample were loaded (1 µL)
onto a nanoflow UHPLC column (PepMap RSLC, C18, 2 µm, 100 Å, 50 µm x 150 mm, Thermo
Scientific) equipped with a titanium inline filter frit (0.5 µm). The flow rate of mobile phases was
300 nL/min. Chromatographic separation was achieved using a gradient beginning at 10 % mo-
bile phase B (98 % acetonitrile, 2 % water, and 0.1 % formic acid) and 90 % mobile phase A (2
% acetonitrile, 98 % water, and 0.1 % formic acid) kept for 2 minutes. Thereafter the gradient
increased to 95 % over 15 minutes. This level of 95 % B was kept for another 10 minutes. The
conditions were restored to 10 % mobile phase B over 0.5 minutes followed by 12.5 minutes of
equilibration time, leading to a total runtime of 40 minutes. In between each injection the needle
and fluidics were washed with 200 µL of 80 % acetonitrile and 0.1 % formic acid in water. The
pump systems were rinsed every hour with a seal wash solution of 10 % methanol and 0.1 %
formic acid in water. All solvents used were of UHPLC-MS grade. The mass spectrometric anal-
ysis was performed on a high-resolution tandem mass spectrometer (Q Exactive HF, Thermo
Scientific). Analytes were ionised by electrospray ionisation using an EASY-Spray ion source.
The applied spray voltage was 1.50 kV during positive polarity and1.70 kV during negative po-
larity with a capillary temperature of 250 °C and an S-lens RF level of 50. No sheath, aux, and
sweep gas was used.
HRMS acquisition was done in either full scan mode for quantification or iterative data-depend-
ent fragmentation (ddMS
2
) mode for identification [10]. Both the positive and negative polarity
modes were used. Full scan acquisition was recorded using a resolution of 240K at m/z 200, an
automatic gain control (AGC) target of 1e6, a maximum injection time of 100 ms, and a scan
range of 70-1050 m/z for positive mode and 100-1500 m/z for negative mode. ddMS
2
acquisition
was done using full scan settings with a resolution of 240K, AGC target of 1e6, maximum IT of
100 s, and scan range of 120-1500 m/z at m/z 200 for positive mode, and 100-1500 m/z at m/z
200 for negative mode. ddMS
2
settings used a resolution of 15K, maximum IT of 50 s, an isola-
tion window of 1.0 m/z, AGC target of 5e4, loop count of 5, and stepped collision energies of 30,
70, and 120 NCE. The acquisition was performed with a dynamic exclusion of 5 s, minimum
AGC target of 500, charge exclusion of >2, and an apex trigger between 2-6 s. An estimated
chromatic peak width (FWHM) was set to 3 s. Sub-ppm mass accuracy was ensured by real
time calibration of a lock mass of 371.10124 (polysiloxane from air) during positive polarity and
112.98563 (sodium formate cluster) during negative polarisation [11], [12]. Calibration of the
mass spectrometer was performed with Pierce™ LTQ Velos ESI Positive and Negative Ion Cal-
ibration Solutions (Thermo-Fisher Scientific).
Instrumental performance was ensured by regular monitoring of an in-house laboratory quality
control sample prepared from fetal bovine serum.
Appendix 2.2
Gas chromatography high-resolution mass spectrometry
GC-HRMS analysis was achieved using an Orbitrap mass spectrometer (Exactive GC, Ther-
moFisher Scientific) with a TriPlus autosampler and a TraceGOLD TG-5MS analytical column
(30 m, 0.25 µm, 0.25 mm, 5% phenyl - 95% dimethyl polysiloxane phase, ThermoFisher Scien-
tific) installed in a TRACE 1310 GC (ThermoFisher Scientific). As described in the HITLIST2
report, one-microliter sample extract was injected sandwiched with air using a split-splitless
mode at 280 °C and 70 mL/min split flow after 60 sec. The column was operated with high purity
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helium at 1.00 mL/min and a temperature program; initial 60 °C with 2 min hold and ramped (5
°C/min) to 240 °C and further (10 °C/min) to 300 °C with a final holding time of 16 min. Analytes
were transferred using a MS-transferline at 280 °C and ionized using electron impact ionisation
(EI) at 70 eV with a 12 minutes filament delay. The Orbitrap HRMS system was operated in full
scan mode (m/z 50 to 750) at a 60,000 resolution in centroid mode and an automatic gain-
control target of 1e6 ions. The Q Exactive HRMS system was tuned and calibrated on a daily
basis using FC43.
Appendix 2.3
CapLC-HRMS/MS for PFC analysis
Same system as described under Appendix 2.1 was utilized, however retrofitted with micro-bore
UHPLC analytical column for PFC analysis. Chromatographic separation was performed on a
Dionex Ultimate 3000 NCS-3500RS high-flow system (Thermo Scientific). Ready samples were
stored in plastic vials in a Dionex WPS-3000 TPL RS autosampler at 8°C. Sample were loaded
(1 µL) onto an UHPLC column (Phenomenex, C18, 3 µm, 100 Å, 75 µm x 150 mm) equipped
with a 20 mm guard column with same material and inner diameter. The flow rate of mobile
phases was 1000 nL/min. Chromatographic separation was achieved using a gradient beginning
at 10 % mobile phase B (10 mM NH
4
Ac in 60 % MeCN) and 90 % mobile phase A (10 mM
NH
4
Ac in 10% MeCN) kept for 2 minutes. In between each injection the needle and fluidics were
washed with 200 µL of 80 % acetonitrile and 0.1 % formic acid in water. The pump systems
were rinsed every hour with a seal wash solution of 80 % methanol and 0.1 % formic acid in
water. All solvents used were of UHPLC-MS grade. The mass spectrometric analysis was per-
formed as described in Appendix 2.1.
Appendix 2.4
Sample preparation for inorganic element analysis (ICP-MS)
Sample aliquots of 0.2 grams for inorganic element analysis were acid extracted using inverse
aqua regia (6 ml Merck Suprapure HNO
3
+ 2 ml Merck Suprapure HCl) in an Anton Paar Multi-
wave 7000 microwave oven according to EPA method 3051A and subsequently diluted with MQ
water and analysed by an Agilent 7900 ICP-MS for 61 elements. For quality assessment and
control, 3 procedural blanks, 2 duplicate samples (for Roskilde and Herning sludge) and 6 Cer-
tified Reference Material samples (3 ERM-CC144 and 3 IMEP-21) were digested and measured
with the samples. Elemental analysis under the NOVAVA programme is done by ICP-MS and
includes the whole periodic table from lithium (third element) to uranium (92
nd
element). Ele-
ments above uranium; neptunium, plutonium and americium are radioactive but the first two can
be found in low concentrations in uranium ores, and the remaining elements from 95 to 118
have only been synthesised in labs or during nuclear fission testing. Some elements is not ana-
lysed by ICP-MS due to use as internal standards (typically rhodium, iridium and indium), or
used as plasma source and collision cell (argon, helium) or as digestion acids (hydrogen, oxy-
gen, nitrogen, chloride and for total dissolution fluoride and boron). The elements normally mon-
itored in NOVANA are mercury, cadmium, lead, nickel, chromium, arsenic, copper, silver (in
biota) and zinc.
Appendix 2.5
Sample preparation for organic micropollutant analysis
Sample aliquots of 0.2 grams were mixed with 5 grams of pre-washed diatomaceous earth and
placed in 10 mL pressurized liquid-extraction cells pre-fitting with glass fibre filters. Cells were
spiked with internal standards. Capped PLE cells were extracted twice in two extracts; two cy-
cles with methanol:water (1:1) followed by two cycles with dichloromethane:hexane (1:1). Pre-
heat time was 5 minutes, purge volume 60% and purge time 60 seconds. Methanol:water ex-
tracts were directed towards LC-HRMS analysis, while DCM:hexane extracts were prepared for
GC-HRMS analysis. Methanol:water extracts were prior to LC-analysis purified using 500 mg
HLB solid-phase material.
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Appendix 2.6
Quality control samples
Four types of quality control samples were prepared; 1) laboratory procedural blanks by per-
forming entire sample preparation workflow without adding any sample matrix. These samples
would be used for background filtration. 2) A pooled sample by combining all sample extracts.
3) A composite sample were made by aliquoting 0.5 grams of each sample into a pool. 4) Two
certified reference materials of ICP-MS analyses; ERM-CC144 and IMEP-21. Calibration stand-
ards were prepared by adding 0, 50, 100, 150, and 200 ng internal standards (see Table 7) into
five aliquots of 200 µL total pooled quality control sample respectively. A calibration blank was
prepared by adding 50 ng of internal standards into 200 µL methanol.
Appendix 2.7
Post-processing
After acquiring NTS raw data for non-target screening, the bottleneck was the identification or
assigning the correct chemical structure for the features. Here, the feature (the combination of
m/z and retention time) represents a particular compound in the sample. Compound Discoverer
version 3.3, a commercial software package developed by Thermo Fisher Scientific, was used
for peak detection, retention time alignment and peak picking. The workflow displaying the se-
lected processing nodes and the associated workflow connections is given in Figure 4. The
general overview of the NTS workflow used in
Compound Discoverer
for the raw data pro-
cessing.. The raw files obtained in full scan mode (samples, blanks and pooled QCs) and data-
dependent, MS/MS, mode (pooled QCs) were processed. In the workflow, the pooled QCs were
labelled as “identification only” which were used as a source of fragmentation data. The main
preliminary data processing workflow nodes includes input files, select spectra, align retention
times, detect compound and mark backgrounds nodes. The list of features for the ionized com-
pounds present in the samples, blanks and pooled QCs were created by the “Detect Com-
pounds” node. Then, the generated ion list was used by the “Group Compounds” node which
combines chromatographic peaks across the raw files by using their molecular weight and re-
tention time. Afterwards, the “Predict compositions” node predicts elemental compositions for
all features/compounds, which are subsequently annotated against compounds whose chemical
information was previously recorded in mzCloud, ChemSpider (exact mass or formula) and local
database searches against Mass Lists (exact mass with or without RT). “Assign compound an-
notation” node performs spectral similarity search against mzCloud (online database, ddMS2
and/or DIA) and mzVault (inhouse spectral database), for compounds with ddMS2. Finally, the
“Mark Background Compounds” node incorporates blanks to trace features/compounds arising
from sample preparation.
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2622966_0023.png
Figure 5.
The general overview of the NTS workflow used in
Compound Discoverer
for the
raw data processing.
The output of this was a feature list, i.e. a table with m/z and retention time pairs (features) and
their peak area as well as other necessary parameters depending on the nodes used. The fea-
ture was subject to peak prioritization for the purpose of identification and structural elucidation
of contaminants. Peak intensity threshold, blank subtraction, reasonable peak symmetry (sharp
peak apex), reasonable elemental composition predicted from the exact mass and the isotopic
pattern as well as structural similarity match were among the feature prioritization criteria used
(nontarget data processing workflow, Figure 4). Every step of the nontarget workflow leads from
lower identification confidence (level 5) to higher (level 1) suggested by Schymanski et al., 2014.
Briefly, the identification journey was started with the HRMS features with exact masses (level
5), whose unequivocal chemical formulas were computed based on the isotopic pattern of peaks
and adducts (level 4). The plausibility of computed formulas was evaluated by searching against
the online chemical data (e.g. ChemSpider) and in-house-mass list. To move on to level 3, the
tentative chemical structure was searched against the online spectral library through compound
discoverer (e.g. mzCloud) and manual search against MetFrag, SIRUIS and MassBank), and
in-house library (mzVault) using triggered MS2 fragmentation data. Here, tentative candidates
that match MS1 accurate mass and the MS2 fragmentation spectra were identified. The diag-
nostic MS/MS fragment masses and/or ionization behaviour together with the information on
parent compounds were used to categorize the tentative candidates to the plausible/probable
chemical structure (level 2). Then, the identity of the compound was confirmed by comparing it
with MS/MS fragmentation spectra of the analytical reference standard (level 1).
GC EI HRMS were search against NIST and NORMAN libraries. Substances with total spec-
trum scores above 70 were assigned as level 2 identifications, while scores below this value are
assigned as level 3. Substances without chemicals formulas were assigned as level 5.
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2622966_0024.png
Figure 6.
Nontarget data processing workflow for the categorization and confirmation of fea-
tures to identification confidence levels.
Appendix 2.8
Quality assurance of level 1 data
Before compounds were confidently annotation at level 1, these entries were manually curated
according to the workflow below:
1.
2.
A signal-to-noise ratio greater than 5 between at least 1 sample and a corresponding
procedural blank.
Matching retention time (Δt
R
< 0.1 min) between the compounds identified in a quality
control sample and spiked quality control sample as well as a larger peak area in the
spiked quality control sample compared to the unspiked quality control sample.
Matching MS
2
data between sample and the spectral reference entry.
No ambiguity between the compound of interest and isobaric compounds. In the case
where a compound peak cannot be precisely defined on the basis of both retention
time and MS
2
spectrum due to isobaric interferences, its annotation must be down-
graded to at least level 2.
3.
4.
Appendix 2.9
Semi-quantitative predictions
The concentration of identified compounds was estimated by employing the Semi-Quantifica-
tion tool. The ionization efficiency prediction approach that accounts for structural similarity
with standard compounds was used. The CSV file containing SMILES, retention time, signal
(peak area), and standard compounds with known concentrations were subject to the semi-
quantification software. Here, a representative sample (a quality control sample) with a high
number of detects was selected for the concentration estimation. Candidate compounds not
detected in the selected quality control sample were not quantified. Thereby, a total of 513
compounds were subjected to quantification. The concentration for unknown compounds in
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2622966_0025.png
the samples was calculated based on the estimated concentration for the quality control sam-
ple using equation (1).
����
������������
����
=
������������
equation (1)
����
������������
����
������������
Where concentration estimated by Semi-Quant, max peak area used for concentration estima-
tion, concentration of the compound in the individual sample and peak area of the compound in
the sample.
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2622966_0026.png
Appendix 3.
Internal
standards
For use in semi-quantification and as quality assurance of the implemented acquisition work-
flows, several isotope labelled extraction and internal standards were used in the study. An ab-
solute amount of 50 ng of each isotope labelled extraction standards (see Table 4) were added
to each of the 15 PLE packed soil samples before extraction. Only 10 ng of GC-EI standards
were added. After PLE, an additional 50 ng of internal standards (Table 5) were added to the
extracts of all samples. A pooled composite sample was used as post, pre, and non ES-spiked
sample respectively to calculate total (PLE+SPE) extraction recoveries.
Table 6.
Recoveries of isotope labelled extraction standards. N.D., not detected.
Platform
GC-EI
Standard
1,3,6,8-Tetrachloro(13C12)dibenzo-p-dioxin
2,3,7,8-Tetrachloro(13C12)dibenzo-p-dioxin
1,2,3,7,8-Pentachloro(13C12)dibenzo-p-dioxin
1,2,3,4,7,8-Hexachloro(13C12)dibenzo-p-dioxin
1,2,3,6,7,8-Hexachloro(13C12)dibenzo-p-dioxin
1,2,3,7,8,9-Hexachloro(13C12)dibenzo-p-dioxin
1,2,3,4,6,7,8-Heptachloro(13C12)dibenzo-p-dioxin
*Octachloro(13C12)dibenzo-p-dioxin
2,3,7,8-Tetrachloro(13C12)dibenzofuran
1,2,3,7,8-Pentachloro(13C12)dibenzofuran
2,3,4,7,8-Pentachloro(13C12)dibenzofuran
1,2,3,4,7,8-Hexachloro(13C12)dibenzofuran
1,2,3,6,7,8-Hexachloro(13C12)dibenzofuran
1,2,3,7,8,9-Hexachloro(13C12)dibenzofuran
2,3,4,6,7,8-Hexachloro(13C12)dibenzofuran
1,2,3,4,6,7,8-Heptachloro(13C12)dibenzofuran
1,2,3,4,7,8,9-Heptachloro(13C12)dibenzofuran
Octachloro(13C12)dibenzofuran
3,3',4,4'-Tetrachloro(13C12)biphenyl
3,4,4',5-Tetrachloro(13C12)biphenyl
2,3,3',4,4'-Pentachloro(13C12)biphenyl
2,3,4,4',5-Pentachloro(13C12)biphenyl
2',3,4,4',5-Pentachloro(13C12)biphenyl
2,3',4,4',5-Pentachloro(13C12)biphenyl
2,3',4,4',5-Pentachloro(13C12)biphenyl
2,3,3',4,4',5-Hexachloro(13C12)biphenyl
2,3,3',4,4',5'-Hexachloro(13C12)biphenyl
2,3',4,4',5,5'-Hexachloro(13C12)biphenyl
3,3',4,4',5,5'-Hexachloro(13C12)biphenyl
2,2',3,3',4,4',5-Heptachloro(13C12)biphenyl
Retention
time (min)
40.69
42.35
45.44
48.14
48.24
48.46
50.91
N.D.
41.90
44.54
45.17
47.45
47.56
48.00
48.72
49.98
51.3
53.51
39.19
39.57
40.33
40.48
40.83
41.37
42.62
43.24
44.02
44.21
45.41
44.62
43%
58%
57%
58%
31%
56%
33%
25%
40%
10%
42%
44%
49%
47%
45%
42%
48%
44%
47%
49%
54%
41%
Recovery
(%)
50%
50%
49%
11%
19%
22%
<1%
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2,2',3,4,4',5,5'-Heptachloro(13C12)biphenyl
2,3,3',4,4',5,5'-Heptachloro(13C12)biphenyl
nLC-pos
13C3-Caffeine
13C6-Thiabendazole
DEET-D7
Diuron-D6
Imidacloprid-D4
Pirimicarb-D6
nLC-neg
2,4-D-D3
Dicamba-D3
Diuron-D6
Imidacloprid-D4
Mecoprop-D3
cLC-neg
Perfluoro-n-(2,3,4-[13]C3)butanoic acid (
13
C
3
-PFBA)
Perfluoro-n-(1,2-[13]C2)octanoic acid (
13
C
2
-PFOA)
Perfluoro-n-1-(1,2,3,4-[13]C4)octanesulfonate (
13
C
4
-
PFOS)
Perfluoro-n-(1,2-[13]C2)decanoic acid (
13
C
2
-PFDA)
45.6
46.65
14.47
13.81
22.80
23.13
17.87
16.07
22.76
21.10
23.20
17.84
24.08
4.93
5.70
6.44
6.45
36%
42%
88%
69%
68%
82%
87%
76%
94%
<1%
105%
88%
109%
<1%
76%
148%
174%
Table 7.
Signal stability (%RSD) of isotope labelled internal standards. The instrumental %RSD
is calculated from peak areas of repeated injections (n=12) of quality control samples, measured
every 4th injection throughout the instrument acquisition.
Platform
nLC-pos
Standard
13C3-Testosterone-2,3,4
13C4-15N2-Riboflavin
Retention time (min)
23.78
14.89
%RSD
2.67
5.60
The Danish Environmental Protection Agency / HITLIST2
27
MOF, Alm.del - 2021-22 - Bilag 717: Orientering om resultaterne af projekt om undersøgelse af miljøfarlige forurenende stoffer i slam
2622966_0028.png
Appendix 3.1
Signal stability of extraction and internal standards
The signal stability was calculated from the total average of normalised values of all standards
measured in each sample:
1
����
����
− ����
∑(
)
����
����
max ����
����=1
����
Where
x
i
is the peak area of standard
j
in sample
i, µ
is the mean area of standard
j
across all
samples respectively,
x
max
is the maximum peak area for standard
j
across all samples, and N
is the number of standards identified.
100
80
60
40
20
0
-20
-40
-60
-80
-100
ESTD signal deviation from QC mean (%)
Procedural blank
Ejby_1
Ejby_2
Ejby_3
Egå_1
Egå_2
Egå_3
Måløv_1
Måløv_2
Måløv_3
QC_01
QC_02
QC_03
QC_04
QC_05
QC_06
QC_07
QC_08
QC_09
QC_10
QC_11
Herning_1
Herning_2
Roskilde_1
Roskilde_2
Herning_3
Post_spike
Pre_spike
Figure 9.
Average signal difference of the six isotope labelled extraction standards in each
sample from the mean of twelve QC injections on the LC-pos system (13C3-caffeine, DEET-
D7, 13C6-thiabendazole, diuron-D6, pirimicarb-D6, and imidacloprid-D4). Error bars cor-
respond to 1���½�.
28
The Danish Environmental Protection Agency / HITLIST2
Non-spike
QC_12
MOF, Alm.del - 2021-22 - Bilag 717: Orientering om resultaterne af projekt om undersøgelse af miljøfarlige forurenende stoffer i slam
2622966_0029.png
100
80
60
40
20
0
-20
-40
-60
-80
-100
ISTD signal deviation from QC mean (%)
Procedural blank
Ejby_1
Ejby_2
Ejby_3
Egå_1
Egå_2
Egå_3
Måløv_1
Måløv_2
Måløv_3
QC_01
QC_02
QC_03
QC_04
QC_05
QC_06
QC_07
QC_08
QC_09
QC_10
QC_09
QC_11
QC_10
Herning_1
Herning_2
Roskilde_1
Roskilde_2
Herning_3
Post_spike
Pre_spike
Figure 10.
Average signal difference of the two isotope labelled internal standards in each
sample from the mean of twelve QC injections on the LC-pos system (13C3-Testosterone-
2,3,4 and 13C4-15N2-Riboflavin(-)). Error bars correspond to 1���½�.
100
ESTD signal deviation from QC mean (%)
80
60
40
20
0
-20
-40
-60
-80
-100
Procedural blank
Egå_1
Egå_2
Ejby_1
Ejby_2
Roskilde_1
Roskilde_2
Ejby_3
Egå_3
Måløv_1
Måløv_2
Måløv_3
Herning_1
Herning_2
Herning_3
Non-spike
QC_01
QC_02
QC_03
QC_04
QC_05
QC_06
QC_07
QC_08
QC_11
QC_12
QC_12
Pre_spike
Post_spike
Figure 11.
Average signal difference of the four isotope labelled extraction standards in each
sample from the mean of twelve QC injections on the LC-neg system (Diuron-D6, imidacloprid-
D4, mecoprop-D3, and 2,4-D-D3). Error bars correspond to 1���½�.
Non-spike
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MOF, Alm.del - 2021-22 - Bilag 717: Orientering om resultaterne af projekt om undersøgelse af miljøfarlige forurenende stoffer i slam
Appendix 4.
ICP-MS dataset
A complete ICP-MS dataset for 61 elements is available via …MST.dk.
30
The Danish Environmental Protection Agency / HITLIST2
MOF, Alm.del - 2021-22 - Bilag 717: Orientering om resultaterne af projekt om undersøgelse af miljøfarlige forurenende stoffer i slam
Appendix 5.
NTS dataset
The complete NTS dataset is available via …MST.dk.
File “Appendix 5-HITLIST4-GCEI.xlsx” contains all substances from the GC-EI-HRMS dataset.
File “Appendix 5-HITLIST4-LC.xlsx” contains all substances from the LC-HRMS/MS datasets
(nLC and cLC).
The Danish Environmental Protection Agency / HITLIST2
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MOF, Alm.del - 2021-22 - Bilag 717: Orientering om resultaterne af projekt om undersøgelse af miljøfarlige forurenende stoffer i slam
2622966_0032.png
HITLIST4: Non-targeted and suspect screening of sewage sludge
The Danish Environmental
Protection Agency
Tolderlundsvej 5
DK - 5000 Odense C
www.mst.dk