Environmental Science & Technology 
may leach into the environment.” In the case of LC-HRMS, no 
MS/MS data were collected for approximately S0% of the 
compounds, rendering their identification impossible, indicating 
‘hat even more compounds remain unknown (data-dependent 
mode). 
In the BPNS, a clear distinction is observed between OWFSs A 
and B, even though both OWFS are located close to each other. 
The difference could be (partly) explained by the use of different 
technologies for corrosion protection, such as the use of ICCP 
(OWF A) vs sacrificial anodes (OWF B) or the different use of 
coatings like “International” (OWF A) vs “Hempel” (OWF B). 
In the GPNS (Figure 4), most of the features were found in 
more than one OWF, but each OWF also had unique 
compounds that were not identified in other OWFs where 
more stations were sampled. The lowest number of features was 
found in the OWFs with only two stations, where, from a 
statistical point of view, the variation will have a bigger influence 
compared to the other OWFs; therefore, only OWFSs with a 
similar number of stations should be compared. A higher 
emission might thus be expected in OWF C compared with 
OWF G and F, as more compounds are detected in OWF C, 
despite the same number of sampling stations between the three 
impact areas. OWF D counted a lower number of features 
compared to OWF E and H. Here, OWF D was built in 2016, 
more recent than OWF E (2015) and H (2015). A similar 
observation was made in the BPNS, where more compounds 
were detected in the older OWF B compared to OWF A. This 
could indicate that chemical emissions might increase during the 
life stage of the OWFSs and/or that the use of older technology 
might result in higher emissions. Either way, further research is 
needed to fully understand the chemical impact of OWFs 
“hroughout their entire life cycle, taking into account the lifetime 
extension and decommissioning process. 
The higher number of compounds detected in the older 
OWFSs may also indicate that current OWF fingerprints are not 
strongly influenced by chemicals released during the con- 
struction phase, given that these chemicals would disperse over 
me. Additionally, in the BPNS, S0% of the OWF samples were 
collected in the area near a turbine along the residual current, 
where sedimentation can be expected. Taking into account the 
compounds that were more abundantly present in the OWFs, no 
significant increase (Kruskal-Wallis; p > 0.05) was observed in 
:he number of contaminants at samples taken in the 
sedimentation area compared to samples taken perpendicular 
:o the residual current. 
The tentatively identified compounds in the OWFSs are listed 
ın Table S2. An overview of the top-9 chemical families is given 
in Figure 6. Most of the identified compounds belong to diols, 
ollowed by alcohols, carboxylic acids, and amines. These 
chemicals can be released from polyurethane coatings applied to 
wind turbines for corrosion protection.” Organophosphorous 
compounds were also detected, which could be related to the use 
of certain plasticizers or the use of flame retardants (e.g., Castro- 
Jimenez et al.°*). 
3.7. Chemical Fingerprint of the Shipping-Related Area 
The ship ref area is located in the northern part of the BPNS. 
This area is close to shipping lanes with no other anthropogenic 
activities in the vicinity. This resulted in a lower number of 
compounds compared to the high ref area. In total, 143 
compounds were detected with a higher intensity (compared to 
: he low and high ref areas) in the ship ref area in the BPNS. 
Different types of chemicals can be emitted by ships, especially 
pubs.acs.org/est 
NEE 
Amide 
Organophosphonate 
Steroid 
Dial 
Hydroxy u 
Fr 
Peptide 
Amine 
”Alcohol 
Carboxylic a 
Figure 6. Donut chart showing the relative percentage of the top-9 
chemical groups that were tentatively identified (n = 430) in the NTS 
using both GC-MS and LC-HRMS. 
from the coatings used to protect the vessels, whether or not in 
combination with booster biocides.”““° There might also be 
accidental leakages of oils or chemicals transported at sea. In a 
study conducted by Jonkers et al.” nonylphenol ethoxylate, a 
surfactant used to clean cargo ships at open sea, was detected in 
high intensities offshore the Dutch coast. Similarly, undecyl 
hydrogen sulfate (compound LC-MS ESI— 9882), with 
applications as an industrial cleaner, was identified at the ship 
ref (Figure S, compound 9882). Additionally, other similar 
compounds such as 1-decanesulfonoperoxoic acid and 7-octene- 
1,2-diol were detected with a potential application as a bleaching 
agent and antifreeze additive, respectively. In total, 24 out of the 
143 compounds were identified with a predicted applicability in 
polymers and resins, surfactants, household products, and 
pharmaceuticals (Table S2). 
3.8. Chemical Fingerprint in a Near-Shore Related Area 
The near-shore impact samples (high ref area) are situated in the 
<12 nautical mile area, close to different anthropogenic 
activities. Compounds detected at the high ref area have 
potential applications in polymer resins, surfactants, cosmetic 
formulations, or as contraceptives and other pharmaceuticals 
(see Table S2). Most of these compounds are released during 
human activities (household waste, industry, etc.) and are often 
transported by rivers to the marine environment.” This 
process can further be expedited when contaminated sediments 
from ports, harbors, and shipping lanes are dredged and 
disposed of at sea.° A representative profile is provided by 
compound 893, detected by GC-MS and identified as chrysene 
‘Figure S, compound 893), which is a PAH that is mainly 
released during combustion processes. This compound is 
strongly present in industrial ports and their respective dredge 
disposal site.“ Although this compound was also detected in 
OWF A and B in the BPNS, the largely increased peak intensity 
in the high ref area would thus indicate that the main source is 
situated outside the OWFs. Nevertheless, it is not excluded that 
these PAHs can be partly released within the OWFs. 
Naphthalene, for example, is mentioned as an accidental release 
when a leak at the auxiliary emergency generators occurs. >61 
3.9. Natural Occurring Chemicals 
Different steroids (Figure 6 and Table S2), such as cholesterol, 
desmosterol, campesterol, etc., were identified in high 
abundance in the OWFs compared to the reference areas in 
both the BPNS and GPNS. The presence of these steroids in the 
marine sediments of OWFs could be the result of a more 
abundant or different benthic community, resulting in a different 
pattern of metabolites compared to the reference areas. 
nttps://doi.org/10.1021/acs.est.5c17939 
Environ. Sci, Technol, XXXX, XXX, XXX XXX