E alua ion o Pu e PFAS Dec ease in Con olled Se ings
Ma co Mancini, Valen ina Gioia, Fede ica Simone i, Alessand o F ugis, and S e ano Cin i*
Ci e This: h ps://doi.o g/10.1021/acsmeasu esciau.3c00027
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ABSTRACT: Since 1940, poly- o pe luo ina ed alkyl subs ances (PFAS)
ha e been la gely used in many applica ions, including pain s, i e oaming,
household i ems, p oduc packaging, and ab ics. Because o hei
ex emely high pe sis ency, hey ha e been de ined as “ o e e chemicals”.
Al hough he EU is aking ac ion o educe hei use, hei widesp ead
occu ence in en i onmen al ma ices and hei ha m ul e ec s on human
heal h equi e he use o highly pe o ming analy ical me hods o e icien
moni o ing. Fu he mo e, no el PFAS a e cons an ly e ealed by bo h EU
and Na ional en i onmen al agencies. The objec i e o his wo k is o
in es iga e he cause o he signal dec ease du ing he analysis o a s anda d
PFAS mix u e in wa e -based ma ices, by p oposing an e icien echnical
p ocedu e o labo a o y specialis s. The analyses we e ca ied ou on a
mix u e o 30 PFAS, including bo h egula ed and unknown subs ances
(which a e expec ed o be in oduced in he guidelines), cha ac e ized by di e en chemical ea u es, using LC- ials o wo di e en
ma e ials, namely, glass and polyp opylene, and dissol ed in wo sol en s, namely, wa e and wa e −me hanol. The empe a u e o
analysis and he concen a ion o PFAS we e also conside ed h ough LC-MS analyses a di e en imes, in he 0−15 h ange.
Depending on he chemical s uc u e and leng h o he PFAS, sampling and ea men p ocedu es may be adop ed o ackle he
dec ease and he elease om he con aine s, educing he isk o unde es ima ing PFAS also in eal wa e ma ices.
KEYWORDS: PFAS, mass spec ome y, adso p ion, d inking wa e , con aine s
■INTRODUCTION
Poly- o pe luo ina ed alkyl subs ances (PFAS) a e a class o
compounds o mo e han en housand chemicals, consis ing o
a pa ially o ully luo ina ed hyd ophobic alkyl chain wi h
a ying leng h and a unc ional g oup, usually hyd ophilic.
1
These subs ances ha e long been used in a wide ange o
indus ial and comme cial applica ions (e.g., Te lon, Sco ch-
ga d, ood packaging, cosme ics, wa e p oo ex iles, e c.).
2
Howe e , due o hei ex eme pe sis ence and high chemical
s abili y, hey a e now widesp ead e e ywhe e, becoming
known as “ o e e chemicals”.
3−5
As men ioned abo e, PFAS
encompass housands o chemicals, bu en i onmen al s udies
ha e p ima ily ocused on pe luo oalkylsul onic acids (PFSA),
such as he well-known pe luo ooc anesul onic acid (PFOS),
and pe luo oalkylca boxylic acids (PFCA), including pe luo -
ooc anoic acid (PFOA). PFSA and PFCA a e low molecula
weigh su ac an s, consis ing o homologous se ies o
molecules ha di e in he leng h o he luo ina ed alkyl
chain ( ypically C4−C14). Due o hei pe sis ency and
bioaccumula ion, hey ha e been ound in wa e , land, ai ,
ood, and e en human samples.
6−8
In addi ion, due o hei
po en ial oxici y, egula o y ac i i ies a bo h he na ional and
in e na ional le els a e inc easing along wi h he de elopmen
o no el s a egies o bo h de ec and ea con amina ed
ma ices. Pa icula ly, he de elopmen o no el and accu a e
analy ical p ocedu es o de ec ing PFAS is o essen ial
impo ance in e alua ing hei anspo and a e. Va ious
me hods, including ch oma og aphy, mass spec ome y, and
po able senso s, a e cu en ly being de eloped.
9−12
Al hough
all hese app oaches a e highly e icien and sensi i e, PFAS
sampling, s o age, and analysis con inue o ep esen a
challenge.
13−16
The PROMISCES
17
p ojec , en i led P e en ing Recalci-
an O ganic Mobile Indus ial chemicalS o Ci cula
Economy in he Soil-sedimen -wa e sys em, in ends o
iden i y how indus ial pollu ion p e en s he deploymen o
he ci cula economy (CE) in he EU and which s a egies help
o e come key bo lenecks o deli e he ambi ions o he
Eu opean G een Deal and Ci cula Economy Ac ion Plan. As a
consequence o his, new analy ical me hods and oxicological
ools a e equi ed o p o ide da a on pe sis en mobile
subs ances (i.e., PFAS and o he indus ial chemicals) in
complex en i onmen al ma ices eleased om (i) soil, (ii)
sedimen , (iii) land ills, and (i ) was ewa e ea men plan s
and ( ) ia u ban uno in o ele an en i onmen al
Recei ed: June 23, 2023
Re ised: Augus 19, 2023
Accep ed: Augus 28, 2023
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compa men s. As pa o his p ojec , he de elopmen and
alida ion o analy ical me hods o de ec ing and quan i ying
selec ed PFAS compounds in e e se osmosis and nano-
il a ion concen a es, leacha es, sewage sludges, and con-
amina ed sedimen s a e included. As es ablished by analy ical
guidelines, PFAS p o ocols de eloped by he EPA, ASTM, and
o he s ecommend he use o polyp opylene con aine s o
s o age and analysis (including LC ials) and a oidance o
con ac be ween samples and glass su aces.
18
In pa icula , as
epo ed in EPA 8327, one o he o icial LC-MS/MS s anda d
p o ocols o analyzing PFAS in su ace wa e , g oundwa e ,
and was ewa e ma ices, he loss o PFAS was obse ed du ing
he s o age o s anda d solu ions in 50% me hanol using glass
con aine s. To p e en undesi ed dec eases in PFAS
concen a ion, he use o polyp opylene (PP) and high-densi y
polyp opylene (HDPP) con aine s is ecommended.
19
How-
e e , in a ecen wo k, au ho s showed ha he beha io o he
adso p ion o pe luo ooc anoic acid (PFOA) o a ious
con aine s is lowe on glass han on polyp opylene,
espec i ely, 14−23% and 32−42%.
20
Mo eo e , his phenom-
enon was obse ed in long- ime expe imen s o PFAS
emedia ion in eal wa e samples, demons a ing ha sal s
can signi ican ly inc ease he adso p ion.
21
Also, i should be
conside ed ha he p esence o long ca bon chains has a
ele an e ec on he adso p ion on he wall o con aine s, e.g.,
glass, polyp opylene, and he p esence o nonaqueous sol en
migh a oid his issue.
22
Howe e , he adop ion o high-
con en o o ganic sol en s o conduc analysis is no always
p ac icable e en conside ing some s udies ocused on oxici y
o hese species.
23,24
The opic is o high in e es , and a ious
s udies ha e been epo ed in he li e a u e, conside ing he
known PFAS o main in e es .
25−27
In addi ion o he
con aine s and he sol en s used o sampling and s o age,
empe a u e and ime seem o ha e a ole as indica ed by he
es ablished guidelines o he EPA.
28
Howe e , i should be
no ed ha a unique consensus is s ill missing and he lis o
PFAS and ela ed-species is inc easing; hus, new p ocedu es
will need o be de eloped.
29
In his wo k, we applied an
acc edi ed LC/MS/MS me hod, based on EPA 533 and EPA
537.1, o he analysis o 30 PFAS, including bo h
pe luo oalkyl sul onic (PFSA) and ca boxyl compounds
(PFCA). All he analyses ha e been ca ied ou while
conside ing di e en ials ma e ials (glass and polyp opylene),
sol en s (wa e and wa e −me hanol), and empe a u e
condi ions (15 and 25 °C), ac o s ha may a ec PFAS
beha io and which a e mo e equen ly selec ed by acc edi ed
labo a o ies o PFAS analysis. Samples we e eshly p epa ed
di ec ly in he designa ed LC ials, all he same geome ical
shape, and analyzed o e a du a ion o 15 h. Adop ing a
sys ema ic app oach, all PFAS ha e been kine ically cha ac-
e ized in o de o unde s and how di e en expe imen al
condi ions may a ec hei a ailabili y by a oiding alse
nega i e esul s du ing measu emen s. In addi ion, hese
kine ic s udies p o ided p elimina y da a on he di e en
analyzed species, which a e s ic ly dependen on hei
chemical s uc u es, allowing o he de elopmen o mo e
e icien analy ical p o ocols o PFAS s o age and analysis.
This a icle could ep esen a s a ing poin owa d he
de elopmen o analy ical me hods also o eme gen PFAS,
expec ed o be in oduced in he o icial me hods (i.e., EPA,
EU, na ionals) as ecommended in he PROMISCES p ojec
objec i es.
■MATERIALS AND METHODS
Reagen s and Ins umen s
Op ima LC-MS g ade ace oni ile, ul apu e wa e , and me hanol
we e pu chased om Biosol e. LC-MS g ade (>99%) ammonium
ace a e was pu chased om VWR. Vials (Phenomenex: pa no. AR0-
3611-12) we e pu chased by Phenomenex. Ce i ied S anda ds lis :
PFAS (C4−C10 mix u e) ES-5576 b and CIL, PFCA (C4−C14
mix u e) ES-5587 b and CIL, S anda d PFAS Mix u e (7
componen s), and C6O4 di luo o((2,2,4,5- e a luo o-5-( i luo ome-
hoxy)-1,3-dioxolan-4-yl)oxy)ace ic acid (pu chasing p ocedu e wi h
pe mission, ce i ica e no a ailable) we e pu chased om Ul a
Scien i ic (CAS single analy es 757124-72-4,27619-97-2, 39108-34-4,
2991-50-6, 754-91-6, 13252-13-6, 2355-31-9); L-PFUdS 441296-91-
9, L-PFDoS 1260224-54-1, L-PFT DS 174675-49-1, NaDONA
2250081-67-3 and MPFAC-24-ES mix u e we e pu chased by
Welling on Lab. Excep o MPFAC-24-ES (sol en Me hanol/
Isop opanol 2%/wa e 1%), all o he s anda ds lis ed a e in me hanol.
All sol en s and consumables we e moni o ed o PFAS con ami-
na ion in each new lo used.
The UHPLC-MS/MS ins umen se up comp ises a The mo
Scien i ic UHPLC Ul iMa e 3000 sys em equipped wi h pumps, a
e ige a ed au osample , a he mos a ed column compa men , and a
degasse . I is coupled wi h a The mo Scien i ic TSQ Al is iple
quad upole mass spec ome e ea u ing an ESI sou ce. The
ch oma og aphic column used is a Luna Omega 1.6 μm PS C18
100 Å, wi h dimensions o 100 ×2.1 mm, om Phenomenex o an
equi alen . The delay column employed is a Luna 5 μm C18(2) 100
Å, sized a 30 ×3 mm (Phenomenex; Pa No: 00A-4252-Y0). Fo
LC-MS analysis, wo dis inc mobile phases we e chosen: mobile
phase A consis s o wa e wi h 5 mM ammonium ace a e, while
mobile Phase B is composed o ace oni ile (all he ins umen al and
expe imen al condi ions a e ca e ully desc ibed in he Suppo ing
In o ma ion ile, Tables S1−S3).
Expe imen al Se up
Fou ials we e p epa ed o each expe imen and shaken manually
(we obse ed ha he use o o ex sys ems migh acili a e he
adhesion o he PFAS on he su ace o he con aine s). All he
solu ions ha e been p epa ed using bo h di e en sol en s and
con aine s, speci ically: 200 ng/L in polyp opylene ials using wa e as
he sol en , 200 ng/L in polyp opylene ial using wa e −me hanol
70:30 as he sol en , 200 ng/L in glass ials using wa e as he sol en ,
and 200 ng/L in glass ial using wa e −me hanol 70:30 as he sol en .
The same expe imen s ha e also been pe o med using a highe
concen a ion o PFAS, namely, 1 μg/L, and he au osample
empe a u e was se up a 15 and 25 °C. To ob ain a kine ic p o ile
o measu emen s, each solu ion was analyzed a a ious imes,
including 0, 3, 6, 9, 12, and 15 h, as schema ized in Figu e 1.
All ials es ed ha e he same su ace a ea. A delay column was
employed o p e en PFAS elease om he ins umen . Addi ionally,
in o de o assess he po en ial p esence o PFAS in he wo king
ma e ials and in he UPLC sys em (in pa icula PTFE), a
backg ound signal was eco ded be o e each analy ical session.
Acco ding o he EPA guidelines o PFAS analysis, he backg ound
signal should be smalle o 1/3 o he LOQ (Limi o Quan i ica ion).
In ou case, all he analy es in wa e and in wa e −me hanol p esen a
backg ound concen a ion o ze o o a mos <5 ng/L, which is 40
and 200 imes lowe han he concen a ions we a e analyzing (200
ng/L and 1 μg/L, espec i ely) and all cases lowe o ou LOQ (15
ng/L).
■RESULTS AND DISCUSSION
The a ionale o he p oposed s udy was ocused on p o iding
signi ican indica ions on how o handle PFAS compounds
du ing hei sampling and quan i ica ion. PFAS a e gene ally
adso bed on con aine s, causing a majo sou ce o e o in bo h
he sampling and analysis phases. Al hough he EPA and o he
agencies mainly sugges he use o PP con aine s, he deba e is
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s ill ongoing, and da a o jus i ica ion a e sca ce. Since he
chemical composi ion o PFAS, hei concen a ion, he
analy ical empe a u e, he s o ing/wo king sol en and he
con aine s ep esen impo an a iables o be conside ed, all
he measu emen s ha e been pe o med using a alida ed LC-
MS me hod on a mix u e o 30 PFAS. In o de o ha e a
clea e discussion o he esul s, he lis o analyzed PFAS ha e
been classi ied unde i e g oups depending on he occu ing
simila i ies o hei s uc u es, as epo ed in ollowing Table 1.
As desc ibed in Expe imen al Se up, all he analyses ha e
been ca ied ou a ying di e en ac o s (e.g., empe a u e,
sol en s, con aine s, and concen a ion). The changing in
PFAS signal o e 15 h analysis has been epo ed in he
Suppo ing In o ma ion ile (SI), Figu es S1−S20. A e ha ing
ca e ully obse ed all he signal a ia ion o he species
in ol ed in he s udy, al hough some di e ences appea ed,
h ee majo g oups migh be iden i ied wi h espec o he
a ia ion o quan i a ion MS peaks in he 0−15 h ange: G oup
I (no a ia ion), G oup II (baseline a ia ion), and G oup III
(dec ease wi h ime), as epo ed in Table 2.
Wi h ega d o G oup I, which includes he majo i y o
PFAS ha ha e been analyzed, he beha io epo ed in Figu e
2A is consis en wi h simila MS a eas a bo h he s a ing ime
and end ime (15 h), highligh ing how he choice o sol en ,
con aine , concen a ion, and empe a u e does no co e a
majo ole in he adso p ion p ocess, as shown o NaDONA.
Wi h ega d o PFAS analyzed and inse ed in G oup II, he
occu ence o a di e en baseline was obse ed, e en i he
signal did no show signi ican a ia ion o e he analy ical
sec ion, as shown in Figu e 2B. Fo all he concen a ions and
empe a u es ha ha e been conside ed in he s udy, he
measu emen s ca ied ou in he wa e −me hanol mix u e
we e cha ac e ized by he highes MS quan i a ion peaks as
highligh ed o FOSA. As con i med in a ecen s udy,
29
in
hese cases he beha io migh be a ibu ed o he inc eased
pe cen age o me hanol wi h espec o he o he measu e-
men s ha ha e been ca ied ou in wa e , which show a low
signal a he s a ing poin o he measu emen s wi hou any
signi ican dec ease du ing he 15 h. Wi h ega d o G oup III,
he ypical beha io is shown in Figu e 2C. These measu e-
men s a e cha ac e ized bo h by he p esence o a di e en
baseline and he p esence o a signal dec ease du ing ime.
Wi h ega ds o he o me , i can be obse ed how he s a ing
alues a e lowe when wa e is used as he sol en , indica ing
he exis ence o a sol en -e ec on he solubiliza ion o PFAS.
Wi h ega ds he la e , he di e en con aine ha has been
used seems o be esponsible o a di e en in e ac ion wi h he
PFAS in solu ion, and i is demons a ed by he a ia ion o
Figu e 1. Schema ic ep esen a ion o he LC-MS wo k low o
e alua e dec ease o signal du ing 15 h PFAS analysis, and ea men
o educe adso p ion phenomena ha depends on he speci ic
s uc u e o PFAS, he con aine , and he sol en .
Table 1. PFAS “Classi ica ion” Depending on Composi ion/
S uc u e
PFAS
“classi ica ion” lis o analyzed
sul ona es PFBS, PFPeS, PFHxS, PFHpS, PFOS, PFNS, PFDS,
PFUdS, PFDoS, PFT S
ca boxylic acid PFBA, PFPeA, PFHxA, PFHpA, PFOA, PFNA, PFDA,
PFUdA, PFDoA, PFT DA, PFTeDA
elome 4-2 FTS, 6-2 FTS, 8-2 FTS
sul onamides FOSA, N-MeFOSAA, N-E FOSAA
C−O−C GENX, NaDONA, C6O4
Table 2. PFAS “Classi ica ion” Depending on he Va ia ion
o he A ea o he P oduc (Exp essed as Coun s·min)
Calcula ed in he 0−15 h Range
PFAS
“classi ica ion” lis o analyzed
G oup I PFBS, PFPeS, PFHxS, PFHpS, PFOS, PFNS, PFBA, PFPeA,
PFHxA, PFHpA, PFOA, PFNA, PFDA, PFUdA, GENX,
NaDONA, C6O4, 4-2 FTS, 6-2 FTS, 8-2 FTS, N-
MeFOSAA.
G oup II PFDoA, PFDS, FOSA, N-E FOSAA.
G oup III PFT DA, PFTeDA, PFUdS, PFDoS, PFT S.
Figu e 2. E alua ion o quan i a ion MS peak o 1 μg/L (A)
NaDONA, (B) FOSA, and (C) PFT DA. All he LC-MS expe imen s
ha e been conduc ed using a empe a u e o 25 °C up o 15 h. The
expe imen al se up is ep esen ed by wo ypes o con aine s, i.e., glass
and PP, and by wo sol en s, i.e., wa e and wa e −me hanol, as
epo ed in he inse o Figu e 2A.
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signal in he ange o ime in es iga ed. In addi ion o his, o
all he PFAS ha showed his beha io , he dec ease o signal is
as e when he measu emen is ca ied using wa e as he
sol en and PP as he con aine , eaching he lowes signal a e
he i s 3 h and emaining cons an o he es o he
expe imen . This beha io has been obse ed o all he PFAS
ha ha e been inse ed in G oup III, and o all he
concen a ion and empe a u e es ed. Table 3 displays he
signal pe cen age o eco e y ha has been obse ed using 1
μg/L PFAS a 25 °C.
Table 3 displays he a ia ion o MS peak a eas a e 3 and
15 h, by measu ing he lis ed PFAS a 1 μg/L le els. The
pe cen age o eco e y (R%) has been calcula ed by using he
ollowing o mula: (S x/S 0)×100, whe e S 0 ep esen s he
MS quan i a ion peak a ime 0 ( e e ence ime be o e s a ing
analysis) and S x ep esen s he MS quan i a ion peak measu ed
a e a ixed ime o in e es du ing expe imen (Table 3 has
been ob ained using 3and 15, espec i ely, o 3 and 15 h). As
obse ed, when he PFAS we e analyzed in PP, he R% apidly
eached he lowes alue (al eady a e 3 h), while he p esence
o glass con aine showed a slowe adso p ion p ocess,
demons a ing an ac i e ole o he con aine ’s ma e ial owa d
he adso p ion p ocess. The same expe imen s ha e been also
ca ied ou using wa e −me hanol as he wo king sol en ,
highligh ing how his sys em was cha ac e ized by a good R%
o all he 30 PFAS in glass con aine s, ne e lowe han 84%.
In PP con aine s, he sys em was cha ac e ized by a good R%
o all he PFAS excep o PFT S (69%). Mo eo e , he
s eng h o he adso p ion phenomena has been also con i med
by adding a manually mixing s ep o he di e en solu ions
a e he end poin o he s udy, namely 15 h, by measu ing he
Table 3. Pe cen age o Reco e y o PFAS (G oup 3) ±S anda d De ia ion (n= 3) in Wa e Using Glass and PP as he
Con aine s
condi ion/PFAS PFT DA PFTeDA PFUdS PFDoS PFT S
3 h H2O/glass 82% ±10% 80% ±10% 85% ±3% 83% ±5% 84% ±3%
3 h H2O/PP 40% ±5% 20% ±8% 58% ±1% 28% ±17% 30% ±22%
15 h H2O/glass 27% ±1% 16% ±3% 42% ±6% 19% ±4% 25% ±5%
15 h H2O/PP 31% ±1% 20% ±5% 43% ±7% 28% ±3% 17% ±5%
Table 4. Pe cen age o Reco e y ±S anda d De ia ion (n= 3) o PFAS (G oup 3) a e Mixing he Con aine s
condi ion/PFAS PFT DA PFTeDA PFUdS PFDoS PFT S
mixing H2O/glass 81% ±5% 47% ±3% 99% ±3% 52% ±3% 44% ±1%
mixing H2O-MeOH/glass 98% ±7% 93% ±8% 97% ±8% 102% ±15% 100% ±8%
mixing H2O/PP 64% ±3% 28% ±3% 76% ±5% 42% ±3% 20% ±3%
mixing H2O-MeOH/PP 104% ±8% 88% ±7% 100% ±3% 87% ±3% 69% ±15%
Figu e 3. Pe cen age eco e ies (R%) o PFAS mix u e in a concen a ion o 200 ng/L using empe a u es o 25 °C (A) and 15 °C (B) o PFCA
and 25 °C (C) and 15 °C (D) o PFSA.
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pe cen age o eco e y (R%). The esul s a e epo ed in Table
4.
R% has been calcula ed by using he ollowing ela ionship,
(S mix/S 0)×100, whe e S mix ep esen s he MS quan i a ion
peak measu ed ollowing a manual shaking o he con aine s.
The esul s highligh how he only way o ob ain a quan i a i e
eco e y is ep esen ed by he use o glass con aine s and a
wa e −me hanol mix u e as he sol en . In addi ion, i should
be no ed ha he chemical s uc u e o he in ol ed PFAS
(especially he leng h o he chain) s ongly a ec s he
calcula ed alue o R% (Table 4). In ac , wha is obse ed is
he ollowing: a e he inal mixing s ep, he R% calcula ed o
PFT DA is highe han ha o PFTeDA (PFCA); he R%
calcula ed o PFUdS is highe han ha o PFDoS and PFT S
(PFSA).
To in es iga e he con ibu ion o hyd ophobici y o he
su icial bindings o con aine s, he pe cen ages o eco e y (R
%) o pe luo osul onic (PFSC) and pe luo oca boxylic acids
(PFCA) ha e been epo ed as a unc ion o ca bon chain
leng h, as calcula ed in p e ious wo ks.
29
The g aphs we e
cons uc ed using wo se s o da a collec ed a di e en
empe a u es (25 and 15 °C) o he lowe concen a ion o
PFAS mix u e (200 ng/L), as shown in Figu e 3.
Obse a ions e eal ha he adso p ion o PFAS o he
con aine s inc eases o long-chain compounds (>10 ca bon
a oms), esul ing in smalle R% alues. O e all, he da a
con i m a highe adso p ion in wa e , as i p omo es
hyd ophobic in e ac ions.
30
Rega ding he choice o bo h con aine s and sol en s, i is
e y impo an o conside he s uc u e o he wo king
ma e ial. As discussed, like o he mine al su aces, he main
mechanism h ough which hyd ophobic silica acqui es a cha ge
is h ough eac ion wi h H+and OH−ions p esen in he
aqueous solu ion.
30
The isoelec ic poin o silica is a pH 2, so
o highe pH alues, as in his case, i is nega i ely cha ged.
PFAS ha e nega i ely cha ged head g oups; he e o e, he
Coulombic epulsion be ween cha ges should discou age
adso p ion. Ins ead, as shown in Figu e 3, adso p ion occu s.
One possible explana ion may be ela ed o he sol en e ec :
pe luo oalkyl compounds a e cha ac e ized by a luo ina ed
hyd ophobic chain, and hus, hey unde go hyd ophobic
in e ac ions ha educe he high en opy associa ed wi h he
sol a ion e ec o wa e . Despi e he nega i e cha ge, glass is a
hyd ophobic ma e ial capable o binding PFAS. As he chain
leng h inc eases, he hyd ophobici y o PFAS inc eases, making
hem less soluble. This inc ease in hyd ophobici y d i es he
PFAS owa d he solid−liquid in e ace. By agg ega ing on he
su ace o silica h ough hei ails, he exposed su ace a ea o
wa e is educed, and hey agg ega e wi h hyd ophobic silanol
b idges, eo ien ing hemsel es in a hai pin-like mecha-
nism.
30,31
As he solubili y o PFAS dec eases, he PFAS−
PFAS a ini y inc eases, p omo ing he o ma ion o a
monolaye and educing he a e o he dissocia i e p ocess,
which can be neglec ed.
Rega ding he adso p ion o PFAS on PP in an aqueous
solu ion, conside ing he slow pe cen age o eco e y in Table
3, i is easily obse ed ha he p ocess occu s e y apidly. In
his case, PP is a mo e hyd ophobic ma e ial (con ac angle >
90°), and consequen ly, i is mo e a ac i e o long-chain
PFAS. As a esul , in con as o wha is ecommended by
o icial me hods, PP con aine s may no be he bes ma e ials
o analyses.
In bo h cases, me hanol appea s o delay he adso p ion o
PFAS, wi h inc easing solubili y in he o ganic phase.
Rega ding he e ec o empe a u e, i seems o no
signi ican ly a ec he adso p ion, as con i med by p e ious
s udies.
29
Conce ning he e ec o he mix u e’s concen a ion,
eco e ies appea lowe o highe concen a ions, as shown in
Figu e 4, whe e inc eased adso p ion is mainly obse ed o
PFCA.
Figu e 4. E ec o mix u e concen a ion on pe cen age eco e ies o long-chain PFAS.
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In gene al, i was obse ed ha adso p ion is in luenced by
he unc ional headg oup, indica ing ha highe concen a ions
o sul ona es (−SO3−) we e emo ed om he aqueous phase
han ca boxyla es (−CO2−) wi h simila chain leng hs,
p obably due o hei highe hyd ophobici y.
In o de o in es iga e he adso p ion mechanism, kine ic
da a o wo PFAS, namely, pe luo idecansul onic acid
(PFT S) and pe luo o idecanoic acid (PFT DA), wi h simila
chain leng hs bu di e en head g oups we e eco ded a a
highe ime equency. Fo hese wo PFAS, which appea ed o
each equilib ium du ing he expe imen , he adso bed amoun
o so ba e qeq (ng/cm−2) a equilib ium was calcula ed, as
epo ed in Figu e 5.
Since he a ge compounds can only be assessed based on
changes in peak a eas
( )
S
S
C
C
0 0
, he classical kine ics equa ion
o he pseudo-second-o de kine ics (eq 1) was no malized by
C0, whe e C0is he ini ial concen a ion (200 ng/L) (eq 2).
Subsequen ly, he a io /(1 −C /C0) was plo ed agains ime.
q q K q
1 1
eq 2eq
2
= +
(1)
1
1
1
1
cons an
C
C
C
C
0
eq
0
= +
(2)
A linea eg ession was used o i he plo o /(1 −C /C0)
e sus ime, inding excellen linea i y (R2> 0.99) as shown in
Figu e 5B. This demons a es ha PFAS adso p ion o PP
ollows a pseudo-second-o de kine ics, e en wi hin a small
ime window. The e o e qeq was e alua ed om he slope and
he esul ing amoun was no malized o he su ace a ea o he
ials.
32
(The su ace a ea was calcula ed as 2π 1h+ 2π 2l+π 12,
whe e 1and 2a e he diame e s o he ial and hand la e he
heigh and he neck heigh , espec i ely. In ou case, i was
ound o be 10.78 cm2.)
The de e mined amoun s o so ba e a equilib ium (0.026 ±
0.002 ng/cm2 o PFT DA and 0.028 ±0.001 ng/cm2 o
PFT DS) a e unexpec edly high, e en wi hin a sho ime
window, especially o PFT S. This con i ms he signi icance o
selec ing an app op ia e con aine o such s udies, aking in o
accoun he chemical p ope ies o hese molecules.
■CONCLUSION
The aim o he p esen wo k was o p o ide an e ec i e
me hod o e alua e he op imal expe imen al condi ions o
accu a ely measu e PFAS. To do his, 30 PFAS ha e been
selec ed and analyzed wi h a alida ed LC-MS me hodology.
The lis o analyzed PFAS con ains bo h he ones desc ibed by
Eu opean and Na ional agencies and eme gen species. The
main aim o he wo k was o p o ide labo a o y specialis s
some insigh s ega ding he selec ion o he p ope
expe imen al se up when quan i ying PFAS in eal ma ices.
The whole s udy di ided PFAS in o h ee majo g oups,
namely, 1, 2, and 3. In pa icula , while G oups 1 and 2 we e
no signi ican ly a ec ed by he choice o con aine /sol en ,
PFAS belonging o G oup 3 displayed o be s ongly
dependen on he combina ion o con aine and sol en
Figu e 5. (A) Signal a ia ion o e ime (S /S0) eco ded in a ime ange o 0−21 h (±s anda d de ia ion (n= 3)) (con inuous line) and
heo e ically calcula ed kine ic end (in do s). (B) Linea i o PFT DA and PFT S acco ding o a pseudo-second-o de model and (C) so ba e
amoun pe uni su ace a ea (qeq) o each PFAS. Theo e ical calcula ion and i ing we e pe o med h ough MATLAB e sion 2022.
ACS Measu emen Science Au pubs.acs.o g/measu eau A icle
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F
used. As obse ed, he u iliza ion o ce ain sol en /con aine
combina ions migh esul in a loss o PFAS om he wo king
solu ion, hus yielding an unde es ima ion o he eal le el,
e en a e shaking he con aine s. This beha io is s ic ly
dependen on he chemical s uc u e o he PFAS o be
quan i ied; hus, sligh ly di e en p ocedu es should be
adop ed. Fo ins ance, he use o PP con aine s in combina ion
wi h wa e as sol en esul s in a as e adso p ion o PFAS
wi h espec o he use o glass con aine s, mos o all o long-
chain PFAS. The majo a ini y o PFAS o PP con aine s
compa ed o glass is also con i med by he lowe eco e y o
PFAS a e he inal mixing s ep. The esul s ob ained in he
p esence o a 30% amoun o me hanol highligh ed he
dec ease o adso p ion phenomena and he inc ease o
edissolu ion using bo h PP con aine s (good R%) and glass
con aine s (excellen R%). Fo he empe a u e and concen-
a ion e ec s, hey seem o sligh ly a ec he pe cen age
eco e ies (R%). The high pe sis ence o PFAS, pa icula ly in
he en i onmen , makes hem a op p io i y o socie y as a
whole, especially when conside ing hei heal h e ec s.
The e o e, he p ima y aim o his s udy is o shed ligh on
he impo ance o selec ing app op ia e con aine s, empe -
a u es, and sol en s. Sampling and ea men a e c ucial s eps
ha mus be ca e ully conside ed p io o analysis, and i could
be concluded ha i only PFAS om G oup 1 a e analyzed,
wa e samples in bo h glass and PP can be used as is, while i
PFAS om G oups 2 and/o 3 ha e o be analyzed, he
p e e ed me hod is o use a 70/30 wa e −me hanol mix u e in
a glass con aine .
■ASSOCIATED CONTENT
*
sı Suppo ing In o ma ion
The Suppo ing In o ma ion is a ailable ee o cha ge a
h ps://pubs.acs.o g/doi/10.1021/acsmeasu esciau.3c00027.
Expe imen al se up, MS ansi ions, ime analysis du ing
15 h o all he PFAS and conside ing concen a ions,
namely, 200 and 1 μg/L, and empe a u es, 15 and 25
°C (PDF)
■AUTHOR INFORMATION
Co esponding Au ho
S e ano Cin i −Depa men o Pha macy, Uni e si y o
Naples “Fede ico II”, 80131 Naples, I aly; BAT Cen e -
In e uni e si y Cen e o S udies on Bioinspi ed Ag o-
En i onmen al Technology, Uni e si y o Naples “Fede ico
II”, 80055 Naples, I aly; o cid.o g/0000-0002-8274-
7452; Email: [email p o ec ed]
Au ho s
Ma co Mancini −Depa men o O ganic Mic opollu an s,
Acea Elabo i, 00191 Rome, I aly
Valen ina Gioia −Depa men o O ganic Mic opollu an s,
Acea Elabo i, 00191 Rome, I aly
Fede ica Simone i −Depa men o Chemis y and D ug
Technologies, Sapienza Uni e si y o Rome, 00185 Rome,
I aly
Alessand o F ugis −Depa men o Resea ch, Acea Elabo i,
00191 Rome, I aly
Comple e con ac in o ma ion is a ailable a :
h ps://pubs.acs.o g/10.1021/acsmeasu esciau.3c00027
Au ho Con ibu ions
The manusc ip was w i en h ough con ibu ions o all
au ho s. All au ho s ha e gi en app o al o he inal e sion o
he manusc ip . CRediT: Ma co Mancini concep ualiza ion,
da a cu a ion, me hodology, esou ces; Valen ina Gioia
concep ualiza ion, da a cu a ion, o mal analysis; Alessand o
F ugis esou ces, w i ing- e iew & edi ing; S e ano Cin i
concep ualiza ion, da a cu a ion, supe ision, w i ing-o iginal
d a , w i ing- e iew & edi ing.
No es
The au ho s decla e no compe ing inancial in e es .
■ACKNOWLEDGMENTS
The esul s o his s udy a e a p oduc o he PROMISCES
P ojec unded by Eu opean Union’s Ho izon 2020 esea ch
and inno a ion p og am unde G an Ag eemen No
101036449.
■REFERENCES
(1) Gluge, J.; Sche inge , M.; Cousins, I. T.; DeWi , J. C.;
Goldenman, G.; He zke, D.; Wang, Z.; e al. An o e iew o he uses
o pe -and poly luo oalkyl subs ances (PFAS). En i onmen al Science:
P ocesses &Impac s 2020,22 (12), 2345−2373.
(2) Gaines, L. G. His o ical and cu en usage o pe -and
poly luo oalkyl subs ances (PFAS): a li e a u e e iew. Ame ican
Jou nal o Indus ial Medi-cine 2023,66 (5), 353−378.
(3) Joudan, S.; Lundg en, R. J. Taking he “F” ou o o e e
chemicals. Science 2022,377 (6608), 816−817.
(4) Mi anda, D. D. A.; Leonel, J.; Benskin, J. P.; Jo-hansson, J.;
Ha je, V. Pe luo oalkyl sub-s ances in he wes e n opical A lan ic
ocean. En i on. Sci. Technol. 2021,55 (20), 13749−13758.
(5) Wang, Y.; Kim, J.; Huang, C. H.; Hawkins, G. L.; Li, K.; Chen,
Y.; Huang, Q. Occu ence o pe -and poly luo oalkyl subs ances in
wa e : a e iew. En i onmen al Science: Wa e Resea ch &Technology
2022,8(6), 1136−1151.
(6) Ghisi, R.; Vame ali, T.; Manze i, S. Ac-cumula ion o
pe luo ina ed alkyl subs ances (PFAS) in ag icul u al plan s: A
e iew. En i onmen al esea ch 2019,169, 326−341.
(7) B own-Leung, J. M.; Cannon, J. R. Neu o ansmission a ge s o
pe -and poly luo oalkyl subs ance neu o oxici y: mechanisms and
po en ial implica ions o ad e se neu ological ou comes. Chem. Res.
Toxicol. 2022,35 (8), 1312−1333.
(8) Zhi, Y.; Lu, H.; G iege , K. D.; Munoz, G.; Li, W.; Wang, X.; He,
Q.; Qian, S. Bioaccumula ion and ansloca ion o 6:2 luo o elome
sul ona e, GenX, and pe luo oalkyl acids by u ban spon aneous
plan s. ACS ES&T Enginee ing 2022,2(7), 1169−1178.
(9) Dodds, J. N.; Hopkins, Z. R.; Knappe, D. R.; Bake , E. S. Rapid
cha ac e iza ion o pe -and poly luo oalkyl subs ances (PFAS) by ion
mobili y spec ome y-mass spec ome y (IMS-MS). Analy ical
chemis y 2020,92 (6), 4427−4435.
(10) Munoz, G.; Liu, J.; Vo Duy, S.; Sau e, S. Analysis o F-53B,
Gen-X, ADONA, and eme ging luo oalkyle he subs ances in
en i onmen al and biomoni o ing samples: A e iew. T ends in
En i onmen al Analy ical Chemis y 2019,23, No. e00066.
(11) A eia, M.; Alsbaiee, A.; Ka an il, T.; Dich el, W. E icien PFAS
emo al by amine- unc ionalized so ben s: c i ical e iew o he
cu en li e a u e. En i onmen al Science &Technology Le e s 2019,6
(12), 688−695.
(12) Singh, S.; Wang, J.; Cin i, S. An o e iew on ecen p og ess in
sc een-p in ed elec oanaly ical (bio) senso s. ECS Senso s Plus 2022,
1, 023401.
(13) Shoemake , J. A. D. T.; Te enho s , D. Me hod 537.1:
de e mina ion o selec ed pe -and poly luo ina ed alkyl subs ances in
d inking wa e by solid phase ex ac ion and liquid ch oma og aphy/
andem mass spec ome y (LC/MS/MS); Na ional Cen e o
En i onmen al Assessmen : Washing on, DC, 2018.
ACS Measu emen Science Au pubs.acs.o g/measu eau A icle
h ps://doi.o g/10.1021/acsmeasu esciau.3c00027
ACS Meas. Sci. Au XXXX, XXX, XXX−XXX
G
(14) Woudneh, M. B.; Chand amouli, B.; Hamil on, C.; G ace, R.
E ec o sample s o age on he quan i a i e de e mina ion o 29
PFAS: obse a ion o analy e in e con e sions du ing s o age. En i on.
Sci. Technol. 2019,53 (21), 12576−12585.
(15) Ko onaiou, L. A.; Nannou, C.; Xan hopoulou, N.; Se e oudi,
G.; Bikia is, D.; Lamb opoulou, D. A. High- esolu ion mass
spec ome y-based s a egies o he a ge analysis and suspec
sc eening o pe -and poly luo oalkyl subs ances in aqueous ma ices.
Mic ochemical Jou nal 2022,179, 107457.
(16) Teymoo ian, T.; Munoz, G.; Vo Duy, S.; Liu, J.; Sau é, S.
T acking PFAS in D inking Wa e : A Re iew o Analy ical Me hods
and Wo ldwide Occu ence T ends in Tap Wa e and Bo led Wa e .
ACS ES&T Wa e 2023,3(2), 246−261.
(17) PROMISCES: P e en ing Recalci an O ganic Mobile Indus ial
chemicalS o Ci cula Economy in he Soil-sedimen -wa e sys em;
H2020-LC-GD-2020-3 (RIA) Numbe 101036449. DOI: 10.3030/
101036449. Webpage EU: h ps://co dis.eu opa.eu/p ojec /id/
101036449 (accessed 7 Augus 2023).
(18) Simon, J. A.; Ab ams, S.; B adbu ne, T.; B yan , D.; Bu ns, M.;
Cassidy, D.; Wice, R.; e al. PFAS Expe s Symposium: S a emen s on
egula o y policy, chemis y and analy ics, oxicology, anspo / a e,
and emedia ion o pe -and poly luo oalkyl subs ances (PFAS)
con amina ion issues. Remedia ion 2019,29 (4), 31−48.
(19) Denly, E.; Mo in, K. A e iew o d a En i onmen al
P o ec ion Agency Me hod 1633: A da a use ’s pe spec i e.
Remedia ion Jou nal 2022,32 (1−2), 91−95.
(20) La h, S.; Knigh , E. R.; Na a o, D. A.; Kookana, R. S.;
McLaughlin, M. J. So p ion o PFOA on o di e en labo a o y
ma e ials: Fil e memb anes and cen i uge ubes. Chemosphe e 2019,
222, 671−678.
(21) Al es, A. V.; Tsianou, M.; Alexand idis, P. Fluo ina ed
su ac an adso p ion on mine al su aces: implica ions o PFAS
a e and anspo in he en i onmen . Su aces 2020,3(4), 516−566.
(22) Sö engå d, M.; Os blom, E.; Köhle , S.; Ah ens, L. Adso p ion
beha io o pe -and poly luo alkyl subs ances (PFASs) o 44 ino ganic
and o ganic so ben s and use o dyes as p oxies o PFAS so p ion.
Jou nal o En i onmen al Chemical Enginee ing 2020,8(3), 103744.
(23) Zhang, C.; McEl oy, A. C.; Libe a o e, H. K.; Alexande , N. L.
M.; Knappe, D. R. S abili y o pe -and poly luo oalkyl subs ances in
sol en s ele an o en i onmen al and oxicological analysis. En i on.
Sci. Technol. 2022,56 (10), 6103−6112.
(24) Libe a o e, H. K.; Jackson, S. R.; S yna , M. J.; McCo d, J. P.
Sol en sui abili y o HFPO-DA (“GenX” pa en acid) in
oxicological s udies. En i onmen al science & echnology le e s 2020,
7(7), 477−481.
(25) Tang, C. Y.; Fu, Q. S.; Gao, D.; C iddle, C. S.; Leckie, J. O.
E ec o solu ion chemis y on he adso p ion o pe luo ooc ane
sul ona e on o mine al su aces. Wa e esea ch 2010,44 (8), 2654−
2662.
(26) Bhagwa , G.; T an, T. K. A.; Lamb, D.; Sena hi ajah, K.;
G ainge, I.; O’Conno , W.; Juhasz, A.; Palanisami, T. Bio ilms
enhance he adso p ion o oxic con aminan s on plas ic mic o ibe s
unde en i onmen ally ele an condi ions. En i on. Sci. Technol.
2021,55 (13), 8877−8887.
(27) Liu, Y. L.; Sun, M. Ion exchange emo al and esin egene a ion
o ea pe -and poly luo o-alkyl e he acids and o he eme ging PFAS
in d inking wa e . Wa e esea ch 2021,207, 117781.
(28) Ta asoli, E.; Luek, J. L.; Malley, J. P.; Mouse , P. J. Dis ibu ion
and a e o pe -and poly luo oalkyl subs ances (PFAS) in was ewa e
ea men acili ies. En i onmen al Science: P ocesses &Impac s 2021,
23 (6), 903−913.
(29) Zenobio, J. E.; Salawu, O. A.; Han, Z.; Adeleye, A. S.
Adso p ion o pe -and poly luo oalkyl subs ances (PFAS) o con ain-
e s. Jou nal o Haza dous Ma e ials Ad ances 2022,7, 100130.
(30) Sha ique, U.; Do n, V.; Paschke, A.; Schuu mann, G.
Adso p ion o pe luo oca boxylic acids a he silica su ace. Chem.
Commun. 2017,53 (3), 589−592.
(31) Du, Z.; Deng, S.; Bei, Y.; Huang, Q.; Wang, B.; Huang, J.; Yu,
G. Adso p ion beha io and mechanism o pe luo ina ed compounds
on a ious adso ben s�A e iew. Jou nal o haza dous ma e ials 2014,
274, 443−454.
(32) Xiao, X.; Ul ich, B. A.; Chen, B.; Higgins, C. P. So p ion o
poly-and pe luo oalkyl subs ances (PFASs) ele an o aqueous ilm-
o ming oam (AFFF)-impac ed g oundwa e by biocha s and
ac i a ed ca bon. En i on. Sci. Technol. 2017,51 (11), 6342−6351.
ACS Measu emen Science Au pubs.acs.o g/measu eau A icle
h ps://doi.o g/10.1021/acsmeasu esciau.3c00027
ACS Meas. Sci. Au XXXX, XXX, XXX−XXX
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