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To quantify the occurrence of ingested plastic in fish species caught at different geographical positions in the North Sea, and to test whether the fish condition is affected by ingestion of plastics, 1203 individual fish of seven common North Sea species were investigated: herring, grey gurnard, whiting, horse mackerel, haddock, Atlantic mackerel, and cod. Plastic particles were found in 3.2 % of the examined fish and in five of the seven species. In most cases only one particle was found per fish, ranging in sizes from 0.04 to 4.8 mm, with a median size of 0.6 mm. The frequency of fish with a plastic particle was significantly higher (7.2%) in the southern North Sea, than in the northern North Sea above 55°N (1.3%). The highest frequency (>33%) was found in cod from the British Channel. In addition, small fibres were initially detected in most of the samples, but their abundance sharply decreased when working under special clean air conditions. Therefore these fibres were considered to be artefacts related to air born contamination and were excluded from the analyses. No relationship was found between the condition of the fish and the ingested small plastic particles.
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Plastic in North Sea Fish
Edwin M. Foekema,*
Corine De Gruijter,
Mekuria T. Mergia,
Jan Andries van Franeker,
AlberTinka J. Murk,
and Albert A. Koelmans
IMARES Wageningen UR, Department Experimental Ecology, P.O. Box 57, 1780 AB Den Helder, The Netherlands
Wageningen University, Division of Toxicology, Tuinlaan 5, 6703 HE Wageningen, The Netherlands
Wageningen University, Aquatic Ecology and Water Quality Management Group, Department of Environmental Sciences, P.O. Box
47, 6700 AA Wageningen, The Netherlands
IMARES Wageningen UR, Department Ecosystems, P.O. Box 167, 1790 AD Den Burg (Texel), The Netherlands
SSupporting Information
ABSTRACT: To quantify the occurrence of ingested plastic in sh species caught
at dierent geographical positions in the North Sea, and to test whether the sh
condition is aected by ingestion of plastics, 1203 individual sh of seven common
North Sea species were investigated: herring, gray gurnard, whiting, horse mackerel,
haddock, atlantic mackerel, and cod. Plastic particles were found in 2.6% of the
examined sh and in ve of the seven species. No plastics were found in gray
gurnard and mackerel. In most cases, only one particle was found per sh, ranging
in size from 0.04 to 4.8 mm. Only particles larger than 0.2 mm, being the diameter
of the sieve used, were considered for the data analyses, resulting in a median
particle size of 0.8 mm. The frequency of sh with plastic was signicantly higher
(5.4%) in the southern North Sea, than in the northern North Sea above 55°N
(1.2%). The highest frequency (>33%) was found in cod from the English
Channel. In addition, small bers were initially detected in most of the samples, but
their abundance sharply decreased when working under special clean air conditions. Therefore, these bers were considered to be
artifacts related to air born contamination and were excluded from the analyses. No relationship was found between the
condition factor (sizeweight relationship) of the sh and the presence of ingested plastic particles.
The amount of marine litter is ever increasing, and consists up
to 60 to 80% out of plastics.
Accumulation of plastic is
therefore recognized as one of todays major marine water
quality problems,
and it is assumed that the amount disposed
will increase due to land-based sources as well as to maritime
As most plastic debris is buoyant,
it can be
transported by currents and winds, resulting in a widespread
occurrence across the oceans.
The distribution is very patchy,
as it is aected by local wind and current conditions, coastal
geography, and by the way plastic enters the system.
Plastics are very persistent
but are known to degrade into
smaller pieces.
Degradation in water is particularly slow due
to reduced UV exposure and lower temperatures in the water
compared to land.
Therefore, especially low density plastic
types that oat can be broken down by UVB radiation and
become brittle, and break down into microplastics (dened as
<5 mm
and probably even smaller (nano) particles.
Small fragments (<10 mm) are the most common size fractions
in the ocean gyres.
The actual lifetime of plastic fragments
in the marine environment is unknown; estimates range from
years to centuries, dependent on the polymers physical and
chemical properties.
Over the past 40 years, microplastics in
the North Pacic increased by 2 orders of magnitude.
Large objects of plastic can pose a threat to marine organisms
by entanglement, whereas smaller items are available for
ingestion by many marine organisms including sh. The
occurrence of plastic debris in sh was noticed as early as 1972
by Carpenter et al.
More recently, plastic particles were
encountered in dierent species.
It is suggested that sh
ingest mainly those plastic fragments that have similar color and
shape as their food particles
as is also the case with sea
turtles for which plastic bags resemble jelly sh.
Because of the
wide variety of colors, sizes, and shapes of plastic fragments,
they will probably mimic a wide range of natural food sources.
Several studies described the presence of ingested plastics in
sh (refs 1721, and 2224 but only one
studied plastic in
North Sea sh. The North Sea is among the seas most
intensively used for shing and shipping, so plastic waste is to
be expected. Monitoring studies with Northern Fulmars
revealed ingested plastics in 95% of these birds following a
clear spatial pattern. Northern Fulmars in the Channel area had
the highest plastic burden, and this gradually decreased in
northward direction.
For sh, a relationship between the
Received: February 28, 2013
Revised: June 16, 2013
Accepted: June 18, 2013
© XXXX American Chemical Society |Environ. Sci. Technol. XXXX, XXX, XXXXXX
geographical position on the amount of ingested plastics has
never been studied.
It has been suggested that ingestion of plastics can adversely
impact the condition of animals
by reducing food uptake due
to false feelings of satiation or by causing internal injury or
blockage of the intestinal tract. In addition, it has been
suggested that plastics could enhance the transfer of persistent
organic pollutants to the animals.
As far as we know, the
Table 1. Sampling Dates and Positions, Sample Size, Average Weight and Length, And the Numbers and Percentage of
Individual Herring with Ingested Plastic
catch-date position sample size avg W (g) stdev W(g) avg L(cm) stdev L (cm) ind with plastic % ind with plastics
15-feb-11 51.2N1.46E 42 132 24 27 1.6 1 2
15-feb-11 51.44N1.53E 18 142 35 28 2.0 0 <6
31-jan-11 52.23N2.50E 12 12 4 13 1.3 0 0
31-jan-11 52.23N3.16E 44 17 5 14 1.1 3 7
10-aug-10 56.16N0.33E 25 140 35 25 1.8 0 <4
13-jul-10 56.54N1.53E 25 151 36 25 1.9 0 <4
17-jul-10 58.54N3.46E 25 146 36 25 1.9 0 <4
16-jul-10 59.07N3.44E 25 147 35 25 1.9 1 4
31-jul-10 59.11N0.22E 25 260 69 30 1.9 1 4
11-aug-10 59.19N3.22E 25 136 35 25 1.8 0 <4
12-aug-10 59.36N3.51E 25 215 37 28 1.6 0 <4
29-jul-10 59.42N3.41E 25 272 57 30 1.8 0 <4
13-aug-10 59.44N3.53E 25 212 36 28 1.6 0 <4
14-jul-10 60.10N1.53E 25 151 38 25 1.9 0 <4
4-aug-10 60.11N2.14E 25 277 59 30 1.8 0 <4
19-jul-10 60.14N2.12E 25 261 58 30 2.0 1 4
15-jul-10 60.16N2.22E 25 256 51 30 1.8 0 <4
3-aug-10 60.23N1.54E 25 272 64 30 2.0 0 <4
30-jul-10 60.23N2.06E 25 288 60 30 1.7 0 <4
19-jul-10 60.26N2.12E 25 264 66 30 2.1 0 <4
2-aug-10 60.33N0.27E 25 255 57 30 1.9 0 <4
2-aug-10 60.37N0.31E 25 257 63 30 1.9 1 4
all herring 566 198 95 27 5.2 11 2
Table 2. Sampling Dates and Positions, Sample Size (n), Average Weight and Length, And the Numbers and Percentage of
Individual Fish with Ingested Plastic Per Species for Grey Gurnard, Mackerel, Cod, Whiting, Haddock and Horse Mackerel
catch-date position sample size avg W (g) stdev W(g) avg L(cm) stdev L (cm) ind. with plastic % ind. with plastics
gray gurnard
9-sep-10 55.21N00.65E 62 55 27 17 3.5 0 <2
9-sep-10 55.23N00.52E 26 64 42 18 3.9 0 <4
9-sep-10 55.37N00.45E 83 100 50 21 4.2 0 <1
all gray gurnard 171 0 <1
16-feb-11 50.32N0.34E 48 368 254 33.8 30.7 4 8
14-okt-10 52.45N3.40E 57 134 78 3.6 2.7 2 4
all whiting 105 306 121 32.1 3.5 6 6
horse mackerel
29-sep-10 49.30N3.00W 100 79 16 20.9 1.2 1 1
2-feb-11 56.16N1.26E 48 183 43 27.8 2.0 3 6
7-feb-11 57.13N1.33W 49 202 75 28.3 3.1 3 6
all haddock 97 192 75 28.1 3.1 6 6
1-sep-10 57.14N1.18E 84 226 79 29 3.8 0 <1
17-feb-11 50.56N1.34E 12 3529 2629 64 22.5 1 8
21-feb-11 51.29N3.8E 7 5112 1375 77 8.9 1 14
17-feb-11 51.40N2.37E 28 4280 3512 69 23.7 2 7
17-feb-11 51.8N2.9E 7 1795 1447 52 16.8 1 14
31-jan-11 52.23N2.50E 2 5436 1392 76 10.6 1 50
31-jan-11 52.23N3.16E 11 4 36
2-feb-11 55.49N0.35E 13 472 342 37 7.3 0 <8
all cod 80 3312 3019 61 23.0 10 13
Environmental Science & Technology Article |Environ. Sci. Technol. XXXX, XXX, XXXXXXB
eects of ingested marine plastics on the condition of sh have
never been investigated.
The aims of this study were to quantify the occurrence,
number, and size of plastic particles in sh caught at dierent
geographical positions in the North Sea, and to test the
hypothesis that ingested plastic adversely aects the condition
of the sh. In total 1203 individual sh were sampled covering
seven species: cod (Gadus morhua), whiting (Merlangius
merlangus), haddock (Melanogrammus aeglefinus), herring
(Clupea harengus), horse mackerel (Trachurus trachurus), gray
gurnad (Eutrigla gurnardus), and atlantic mackerel (Scomber
scombrus). Size and weight of the sh were recorded for
calculation of the condition index. Plastic was isolated from the
shesdigestive tract and size and appearance was determined.
The polymer type of a selection of particles was characterized
by infrared spectrometry.
Sampling and Processing. The sh used for this study
were sampled using a Grand Ouverture Verticale (GOV) trawl
with a minimum (cod-end) mesh size of 10 mm during daylight
hours at two periods. Between July and October 2010, 18
samples of herring, three samples of gray gurnard, one sample
of whiting, and one sample of mackerel were collected from the
northern part of the North Sea, between 55°and 60°N. In
January and February 2011, four samples of herring, seven
samples of cod, two samples of haddock, and a single sample of
whiting were collected from the southern part of the North Sea,
between 49°and 56°N. At least 80 individuals from each
species were collected for investigation of the intestines for
plastics, the sampled numbers of individuals per location ranged
between 2 (cod) and 100 (horse mackerel). Sampling locations
and numbers of the collected species are presented in Tables 1
(herring) and 2 (other species).
During the 2010 surveys, the sampled sh was stored directly
at 20 °C. After thawing in the laboratory, length and weight
was determined, and all of the contents of the esophagus,
stomach, and intestines was collected in a jar that was then
lled with a 10% KOH solution (analytical reagent grade,
Fisher Chemical). The amount of KOH added was at least 3
times the volume of the biological material. The jars were
stored at room temperature for 2 to 3 weeks until dissolution of
the organic material was observed to be complete. Jars were not
stirred in order to prevent damage to plastic particles caused by
hard stomach constituents (e.g., shells). Previous tests
conrmed the resistance of plastic particles against 10% KOH
(Mergia, unpublished data). During the 2011 surveys, length
and weight of the sh were measured on board ship and the
complete digestive tract (esophagus, stomach and intestines)
was removed, put in a jar and stored at 20 °C. In the
laboratory, after thawing, 10% KOH solution was added and
the jars were stored for 23 weeks similar to the 2010 samples.
Once the organic material was degraded, the jars content was
sieved (0.2 mm) to collect the nondigestible residue, which was
searched using a stereomicroscope. Plastic particles were
counted per individual sh, and color and shape was described.
Particle size was measured at their largest cross-section. In
2010, this was done roughly using 1 mm as smallest unit, while
in 2011 more accurate measurements were made applying an
ocular micrometer. To get an impression of the polymer
composition of the particles, a selection of six particles
representing the major visually distinguishable classes was
analyzed using Fourier transform infrared spectroscopy (FTIR;
IR-spectrum 4004000 cm1)byTU
̈V-Rheinland Nederland
Five particles smaller than the sieve diameter (0.2 mm) were
discovered, with a minimum size of 0.04 mm, but these were
not included in the analyses. Apart from these particles, very
thin and often less than 1 mm long colored textile bers were
detected in almost every sample. As it was speculated that these
bers could be airborne contamination from clothing, further
sample processing was performed in a clean air ow cabinet
after which the occurrence of these bers strongly declined.
This indicates that utmost precautions are needed to prevent
air borne sample contamination during the whole process of
sample collection and laboratory analysis.
These textile bers
were at least partly considered artifacts and therefore further
excluded from data analysis.
Data Analysis. The frequencies of sh with ingested
plastics in the samples were not normally distributed per area.
In order to test the statistical signicance of dierences between
the Northern and the Southern North Sea the nonparametric
MannWhitney test was applied using the software package
GraphPad PRISM V5.04.
Condition index (K) was calculated from sh weight (W; g),
and body length (L; cm) using Fultons Condition Factor
100 3
The nonparametric MannWhitney test was also applied to
test the signicance of the dierences in body weight, length,
and condition factor between sh with and without ingested
plastics. Dierences were considered signicant at p< 0.05.
Occurrence of Plastics in North Sea Fish. Plastic
particles were detected in ve of the seven sampled species
(Tables 1 and 2). No plastics were found in gray gurnard and
mackerel. Assuming the samples as representative for the
sampled locations this indicates that less than 0.6% of the local
gray gurnards and less than 1.2% of the mackerel contain
ingested plastic. The highest frequency was observed in cod
(13% of the examined individuals), and the lowest in herring
(2%) and horse mackerel (1%). For whiting and haddock,
plastic was found in 6% of the individuals.
Of the 1203 individual sh that were investigated, 33 (2.6%)
contained plastic (Table 3). The highest frequency of sh with
plastics was sampled in the southern North Sea, especially
around 50°N and 52°N. No samples were collected around 53
Table 3. Percentage of Fish with Ingested Plastic As Sampled
in the Southern and Northern, And the Whole North Sea,
Presented Per Species and for All Species Together
area 4955°N5660°N4960°N
n% plastic n% plastic n% plastic
herring 116 1.7 450 0.4 566 1.4
gray gurnard 0 171 0.0 171 <1
whiting 105 5.7 0 105 5.7
horse mackerel 100 1.0 0 100 1.0
haddock 0 97 6.2 97 6.2
mackerel 0 84 0.0 84 <1
cod 67 14.9 13 0.0 80 13
all species 388 5.4 815 1.2 1203 2.6
Environmental Science & Technology Article |Environ. Sci. Technol. XXXX, XXX, XXXXXXC
and 54°N, but from 55°N and further to the north the
frequency of sh with ingested plastics in our samples
decreased (Figure 1). The data show a peak in the frequency
of sh containing plastics in the English Channel. Since the
species composition of the samples varied per area, the
inuence of species or area on the frequency of sh containing
plastics is not clear. For instance, the fact that no plastics were
found in mackerel and gray gurnard that were only sampled in
the northern North Sea, does not imply that these species are
also free of plastics in the southern North Sea.
If all species are included we found ingested plastic in 5.4% of
the sh from the southern North Sea, against 1.2% in the
northern North Sea (Table 3) a dierence that was signicant
(p=<0.001; Figure 2). Herring was the only species for which a
broad set of adequate samples was available for the whole range
of North Sea locations: within this single species the frequency
of individuals with plastics was on average lower in the
northern North Sea without being statistically signicant. Cod
was also sampled in both the southern (5053°N, 6 samples,
67 individuals) and the northern North Sea (55°N, 1 sample,
13 individuals). In all six southern samples plastics were found
in 7 to 50% of the sampled sh (Table 2); none of 13
individuals from the single northern location was found to
contain plastics. In spite of its small number, the cod samples
support the idea that frequency of plastic ingestion is lower in
the northern North Sea. Except for one cod sample, the
northern North Sea samples were all collected in 2010, whereas
the samples from the southern North Sea were collected in
2011. We assumed that no strong annual dierences occurred.
The aforementioned methodological dierences between 2010
and 2011 sample processing may have aected the detection of
the most inconspicuous, especially ber-like plastics. However,
for reasons mentioned earlier, such bers were not included in
our analyses. Therefore, we conclude that the higher frequency
of sh with ingested plastics in the southern North Sea
represents the higher local plastic pollution level. This
observation is in line with ndings from the monitoring of
stomach contents of Fulmars.
The percentage of individual sh containing plastics in our
study ranges per species between 0 and 13% for all North Sea
locations combined, and between 1.2% for all species combined
in the north to 5.4% for those in the south. Such levels compare
roughly to the 9.2% ingestion rate for mesopelagic shes in the
plastic soup of the North Pacic Gyre reported by Davison and
Their sample sizes were too low to report ingestion
rates for separate species, but they noted a dierence of 11.6%
for vertically migrating species to 4.8% for those that do not
regularly migrate to the more polluted surface. Boerger et al.
reported 35% frequency of ingestion in mesopelagic sh from
the gyre, but in their samples cod-end feeding could not be
excluded and may thus overestimate actual frequency of
All our sh samples were obtained from nets
with minimum mesh sizes of 10 mm, which excludes the risk of
cod-end feeding of particles of sizes relevant in our study. A
recent study investigated the presence of ingested plastics in
sh from the English Channel at the southern border of the
area that was sampled for the present study (Latitude 50°16
In that study plastics were encountered in 36.5% of the
sh, which is ve times higher than the frequency we
determined in the Southern North Sea. However, Lusher and
reported that 68% of all encountered particles
consisted of bers, while the smallest bers were excluded in
our study for the reasons stated. It is not clear to what extent
the contribution of such bers was underestimated in our
samples, or was overestimated as a result of air-borne
contamination in the samples of Lusher and colleagues. We
recommend that future research on ingested plastics in sh, as
well as in other organisms, is performed with special
precautions to avoid air-borne contamination with small bers.
The handling of the biological sample (in our case the sh)
Figure 1. Numbers of sh sampled per species in bars, and the percentage of the sh (all species) that contained ingested plastics grouped per degree
N latitude (49 = 49°50°N).
Figure 2. Percentage of sh containing ingested plastics in the samples
from the southern (4954 N) and the northern North Sea (5560
N). For all sampled species (herring, gray gurnard, whiting, horse
mackerel, haddock, mackerel, and cod) together, and for only herring.
Presented are median (horizontal line), 2575 percentiles (box) and
range (bars) of the particles encountered. Statistical signicance
dierences are indicated by *** for p< 0.001.
Environmental Science & Technology Article |Environ. Sci. Technol. XXXX, XXX, XXXXXXD
should then preferably commence with rinsing the outside of
the specimen, while further processing, including dissection
should be done in a clean-air cabinet using dust-free clothing/
Number and Size of the Particles. Of the 33 sh with
plastics, only 6 individuals contained more than 1 particle. The
maximum numbers of particles discovered in one sh was 4
(Table S1 in Supporting Information, SI). All plastic particles
that were encountered were less than 5 mm in size. This is in
line with studies performed in the North Pacic Ocean that
reported microplastics in a size class of 13mminthesh,
and with recent work on sh from the English Channel where
12 mm was the most common size class of ingested
The median size of the particles we found was 0.8
mm. In our North Sea samples, there were no signicant
dierences between particle size classes in the dierent sh
species (Figure 3).
There was no clear relation between particle size and size of
the sh. Particles smaller than 1 mm were found in all size
classes of sh that ranged from 10 cm (herring) to almost 1 m
(cod) (Figure 4). Particles above 1.5 mm were only found in
sh above 20 cm in length, especially whiting and cod.
Dierences between species might be expected due to
dierences in diet, feeding behavior, and size. As planktivorous
species, herring
and horse mackerel
collect their food
primarily by ltering seawater. The fact that only particles
smaller than 1.5 mm were found in the intestine of these
species could indicate that these were ltered from the water
column and ingested with food items. The gadoid species,
and whiting,
are primarily piscivorous and
contained also particles that were larger than what was found in
the planktivorous species. However, since the planktivorous sh
were also smaller than the piscivorous sh, it was not possible
to discriminate the inuence of length from feeding behavior.
However, it is unlikely that the piscivorous sh actively ingested
the particles considering them as food items. The cod in which
plastic particles were discovered ranged in body length between
50 and 90 cm but contained only particles of less than 3 mm.
This is only a fraction of the size of a normal food items for
these shes
and suggests that plastics of such sizes in their
body may reect ingestion by coincidence or secondary
ingestion of plastics incorporated in their prey.
The observation that more than 80% of the sh with plastic
contained only a single particle, suggests that microplastics do
not accumulate inside the digestive tract of these sh for very
long periods.
Types of Plastics. The six plastic particles that were
analyzed with FTIR all were encountered in sh from the
southern North Sea. Two particles consisted of polyethylene
(PE), two particles of polypropylene (PP), and the two other
particles were polyethyleentereftalaat (PET) and styrene-
acrylate (SA), respectively. These results are indicative only,
because the sample size was too small to draw conclusions
about the relative contribution of the individual polymer types
in the ingested particles. Lusher et al.
also found those
polymer types in sh from the English Channel but identied
the bulk of their particles as the semi synthetic cellulosic
material rayon (58%), and polyamide (35%). The high
proportion of such polymers in their results must be linked
to the high proportion (68%) of textile bers in their samples.
Relation with Fish Size and Condition. For most of the
species investigated, the condition factor was comparable for
the sh with and without ingested plastics (Table S2 of the SI).
Only in the case of haddock was the condition factor
signicantly lower for the sh in which plastics were
encountered (p= 0.01). We argue that this observation is
insucient to conrm the hypothesis that plastic aects the
condition index of sh. First, although the dierence for
haddock was signicant, the dierence in the magnitude of the
condition index was marginal (0.85 ±0.06 vs 0.78 ±0.05).
Second, the dierence was found for only one out of 5 species.
Furthermore, the very small size of the plastic particles found
and the limited occurrence suggest that the plastic does not
accumulate in the intestinal tract. The presence of plastics at
the moment of sampling than only indicates that this individual
sh has recently ingested plastic but does not mean it is
structurally more exposed than others. Also, the particles were
too small to expect they can cause feelings of satiation,
intestinal blockage, or play a relevant role as a carrier of
pollutants. In conclusion, it appears unlikely that the amounts
of plastics that we encountered will aect the condition of the
This may be inuenced by particle size relative to sh size.
Impact of the type of plastic particles that we encountered may
be relevant to early life stages of sh, where a particle size of 1
mm is in theory large enough to cause eects like mentioned
above. Early literature, reviewed by Hoss
indicates that
sometimes high ingestion rates have been observed in wild
larval sh, but also mentions laboratory experiments that
suggest that larval and juvenile sh either rejected plastic
particles or passed them through the gut without obvious
Figure 3. Particle size distribution of microplastic detected in North
Sea sh. Presented are median (horizontal line), 2575 percentiles
(box), and range (bars) of the particles encountered.
Figure 4. Size of the ingested plastic particles plotted against body
weight of the sh per species.
Environmental Science & Technology Article |Environ. Sci. Technol. XXXX, XXX, XXXXXXE
damage. Our study cannot shed light on this and further
investigations are recommended.
SSupporting Information
Tables showing additional information. This material is
available free of charge via the Internet at
Corresponding Author
*Phone: +31 317 487122; e-mail:
The authors declare no competing nancial interest.
The authors thank Ingeborg de Boois and the crew of the
research vessel Tridens for assisting in the sh sampling, Andre
Meijboom for his help with identication of plastics, and Ellen
Besseling for her comments on an earlier version of the
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... Kibria (2022) reviewed and compiled a global list of fish species contaminated with MPs, which shows that 09 fish species from the North Sea were contaminated with MPs. Out of 09 species, the following commercial fish species were contaminated with MPs: Atlantic cod, Gadus morhua (piscivorous/carnivorous) (31.4 % of fish ingested MPs) (Lenz et al., 2016); Atlantic herring, Clupea harengus (planktivorous) (23 % of fish ingested MPs) (Lenz et al., 2016); Atlantic horse mackerel, Trachurus trachurus (planktivorous) (1.0 % of fish ingested MPs) (Foekema et al., 2013); Atlantic mackerel, Scomber scombrus (planktivorous) (13.2 % of fish ingested MPs) (Rummel et al., 2016); Common dab, Limanda limanda (carnivorous) (5.4 % of fish ingested MPs) (Rummel et al., 2016); European sprat, Sprattus (planktivorous) (0.005 MPs/fish; 0.25 % fish ingested MPs) (Hermsen et al., 2017); Grey gurnard, Eutrigla gurnardus (carnivorous) (1.0 % of fish ingested MPs) (Foekema et al., 2013); Haddock, Melanogrammus aeglefinus (piscivorous/carnivorous) (6.2 % of fish ingested MPs) (Foekema et al., 2013) and Whiting, Merlangius merlangus (piscivorous/carnivorous) (5.7 % of fish ingested MPs) (Foekema et al., 2013). The MPs ingestion in fish varies between 0.25 % and 31.4 % which may denote low plastic pollution in the North Sea area. ...
... Kibria (2022) reviewed and compiled a global list of fish species contaminated with MPs, which shows that 09 fish species from the North Sea were contaminated with MPs. Out of 09 species, the following commercial fish species were contaminated with MPs: Atlantic cod, Gadus morhua (piscivorous/carnivorous) (31.4 % of fish ingested MPs) (Lenz et al., 2016); Atlantic herring, Clupea harengus (planktivorous) (23 % of fish ingested MPs) (Lenz et al., 2016); Atlantic horse mackerel, Trachurus trachurus (planktivorous) (1.0 % of fish ingested MPs) (Foekema et al., 2013); Atlantic mackerel, Scomber scombrus (planktivorous) (13.2 % of fish ingested MPs) (Rummel et al., 2016); Common dab, Limanda limanda (carnivorous) (5.4 % of fish ingested MPs) (Rummel et al., 2016); European sprat, Sprattus (planktivorous) (0.005 MPs/fish; 0.25 % fish ingested MPs) (Hermsen et al., 2017); Grey gurnard, Eutrigla gurnardus (carnivorous) (1.0 % of fish ingested MPs) (Foekema et al., 2013); Haddock, Melanogrammus aeglefinus (piscivorous/carnivorous) (6.2 % of fish ingested MPs) (Foekema et al., 2013) and Whiting, Merlangius merlangus (piscivorous/carnivorous) (5.7 % of fish ingested MPs) (Foekema et al., 2013). The MPs ingestion in fish varies between 0.25 % and 31.4 % which may denote low plastic pollution in the North Sea area. ...
... Kibria (2022) reviewed and compiled a global list of fish species contaminated with MPs, which shows that 09 fish species from the North Sea were contaminated with MPs. Out of 09 species, the following commercial fish species were contaminated with MPs: Atlantic cod, Gadus morhua (piscivorous/carnivorous) (31.4 % of fish ingested MPs) (Lenz et al., 2016); Atlantic herring, Clupea harengus (planktivorous) (23 % of fish ingested MPs) (Lenz et al., 2016); Atlantic horse mackerel, Trachurus trachurus (planktivorous) (1.0 % of fish ingested MPs) (Foekema et al., 2013); Atlantic mackerel, Scomber scombrus (planktivorous) (13.2 % of fish ingested MPs) (Rummel et al., 2016); Common dab, Limanda limanda (carnivorous) (5.4 % of fish ingested MPs) (Rummel et al., 2016); European sprat, Sprattus (planktivorous) (0.005 MPs/fish; 0.25 % fish ingested MPs) (Hermsen et al., 2017); Grey gurnard, Eutrigla gurnardus (carnivorous) (1.0 % of fish ingested MPs) (Foekema et al., 2013); Haddock, Melanogrammus aeglefinus (piscivorous/carnivorous) (6.2 % of fish ingested MPs) (Foekema et al., 2013) and Whiting, Merlangius merlangus (piscivorous/carnivorous) (5.7 % of fish ingested MPs) (Foekema et al., 2013). The MPs ingestion in fish varies between 0.25 % and 31.4 % which may denote low plastic pollution in the North Sea area. ...
This review paper collected, collated, analysed, interpreted, synthesised, and documented the research investigations conducted on microplastic (MPs) pollution impacts on seafood organisms (including fish, sharks, shrimps, lobsters, crabs, oysters, mussels, and seaweeds) during the last ten years (2012−2022) covering fifty-seven locations/countries in the world. MPs contaminated 926 seafood species comprising 895 finfish, 09 crustaceans, 20 molluscs and 02 seaweeds. Seafood from Asia was found to be most contaminated with MPs. High MP contamination/ingestion was revealed in several seafood organisms. The ingestion of MPs can reduce fish growth and fish fitness, leading to reduced yield/fish production. Fish and seafood play a significant role in supporting the economy, employment, food sources, and livelihoods of people across the globe, which can be threatened due to the contamination of seafood organisms with MPs. MPs have bioaccumulated in fish skin, gills, stomachs, liver, intestine, and muscles as well as dry fish and canned fish. Hence, the consumption of MP-contaminated fresh fish, whole fish, dried fish or canned fish poses risks as it may be a pathway of MP transfer to humans. MPs can increase the health risks to seafood fish consumers since there is a probability that high risks pollutants adsorbed on MPs (heavy metals, pesticides, and oil compounds) can transfer to humans via the food chain. Several of the chemicals (heavy metals, DDT, PAHs) adsorbed onto MPs are carcinogenic. MPs have also been detected in fish meals, therefore, farmed livestock such as aquaculture fish and chicken fed to fish meals can be exposed to MPs and ultimately to humans. Preventive and safety measures are suggested to reduce the exposure of MPs to humans. In addition, several policy strategies are recommended to reduce the impacts of plastic waste and plastic pollution on the environment, aquatic biota, wildlife, seafood and human health.
... Seguidamente los individuos fueron disectados y los tractos gastrointestinales fueron removidos y separados individualmente en tubos de ensayo, cuya boca se cubrió con papel aluminio. La extracción de MP se rea-lizó mediante digestión alcalina seguida por filtrado, siguiendo el protocolo propuesto por Foekema et al. (2013) y modificado por Dehaut et al. (2016). Cada tubo con muestra fue llenado hasta tres veces del volumen del tejido con una solución de KOH al 10% e incubado durante 24 h a 60 °C para digerir la materia orgánica. ...
... Los MP retenidos en los filtros fueron contabilizados y caracterizados según su categoría (fragmento, fibra, espuma, film y pellet) (Crawford y Quinn, 2017), tamaño y color (Foekema et al., 2013). Los MP fueron identificados mediante inspección visual a través de un estereoscopio, confirmados mediante el test de la aguja caliente (Devriese et al., 2015) y agrupados según tipo y color. ...
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Microplastics (MP) have been recorded in marine ecosystems around the world; however, little is known about the temporal and spatial variation of PM on marine beaches in Peru. In this work, PM were evaluated in Emerita analoga (Crustacea: Hippidae) and in the sediments of eight sandy beaches, north and south of the city of Lima, in two seasons. Thirty individuals of E. analoga and sediment samples were collected from each of the eight beaches for each season (winter and summer). The PM were extracted, counted and characterized. An abundance of 0.02 ± 0.13 to 1.82 ± 6.31 PM items/individual was observed in E. analoga and in the sediments they varied from 41 ± 31.07 to 5353 ± 4013 PM items/kg. Fragments were the predominant type in the sediments, whereas fibres were the predominant type in E. analoga. Transparent was the most frequent color. Particle sizes in the sediment ranged mainly between 1000 and 3000 μm, and in E. analoga less than 1000 μm. It can be affirmed that spatio-temporal variation plays a more important role in the dynamics of PM in sediments compared to E. analoga. The abundance of PM in the beach sediment was not related to the proportion of individuals in E. analoga that ingested them, nor with the amount ingested.
... In literature, various effective methods for sample digestion to separate MPs from the biological matrix without destroying MPs have been reported. As reported previously, four groups of agents have been used to digest bio-tissues of aquatic organisms, including acid (De Witte et al., 2014;Van Cauwenberghe and Janssen, 2014;Van Cauwenberghe et al., 2015), bases (Foekema et al., 2013;Rochman et al., 2015), and other strong oxidants (Collard et al., 2015;Nuelle et al., 2014) or enzyme (Cole et al., 2014). A study on appropriate conditions for the removal of bio-tissues without compromising the integrity of MPs is deemed necessary. ...
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In this study, the composition and characteristics of microplastic and artificial fibers in the edible tissue of seven common marine fishes collected from Central Vietnam were evaluated for the first time. The average numbers of micro-debris determined in spined anchovy, whipfin silver-biddy, round scad, stingray, real tuna, daggertooth pike conger, and narrow-barred Spanish mackerel were 0.6 ± 0.2, 0.8 ± 0.3, 1.0 ± 0.4, 0.8 ± 0.2, 1.0 ± 0.4, 0.7 ± 0.3, and 1.0 ± 0.2 per g-ww, respectively. The fiber was the dominant shape (62–77% of total items), and white transparent (40%) was the most common color of the items found. About 75% of the micro-debris found in edible tissue was smaller than 250 μm, and the remaining 25% was about 250–500 μm. Chemical composition analysis confirmed that rayon and polyethylene terephthalate were the two major components among micro-debris found in the fish tissues, accounting for 45 and 34%. Consequently, the estimated annual micro-debris intake based on fish consumption of people in Central Vietnam might range from 33,000 to 50,000 items/person/year. This study provides valuable information on microplastics and nonplastic microfibers in the marine environment, which contributes to the development of strategies for eliminating pollution caused by marine anthropogenic debris.
... To remove the organic content, each gastrointestinal tract content was put in a beaker adding 200 ml of 10% KOH and leaving 24-48 h at 55 • C in the water bath (Foekema et al., 2013;Lusher et al., 2013). ...
Microplastics, as an emergent pollutant, have garnered substantial attention within aquatic environments, yet a significant knowledge gap persists regarding the interplay of organism size and pollution impacts on microplastic uptake in freshwater ecosystems. The main aim of the current study is to assess the microplastic ingestion by aquatic organisms across diverse trophic levels. To achieve this objective, zooplankton, mussels (Anodonta anatina), and fish (Carassius gibelio) were collected from the highly polluted Susurluk River Basin in Türkiye. The size distribution encompassed 160.8 ± 56.9 μm for the prevailing zooplankton, 6.9 ± 2.2 cm for mussel, and 20.4 ± 3.1 cm for fish, respectively. While no microplastic ingestion was observed among zooplankton, the finding highlights the influence of body-size and pollution on microplastic ingestion. In contrast, A. anatina and C. gibelio contained 617 and 792 microplastic particles, respectively. Predominantly, fibers emerged as the most prevalent microplastic type across trophic levels (except zooplankton) followed by films. Notably, only fish exhibited fragments within their gastrointestinal tract. A substantial correlation emerged between microplastic abundance and mussel size and weight, but no such correlation manifested for fish. The study also revealed a positive link between microplastic count and turbidity (phosphate and high Chl a level), impacting mussel ingestion capacity due to the variability in the food availability and potential shifts in feeding preferences. Conversely, no distinct pattern emerged for fish concerning water quality parameters and ingested microplastics. Consequently, our study underscores diverse microplastic uptake patterns in freshwater ecosystems, with a predominant frequency of microplastics falling with the 0.3 mm-3.0 mm range, emphasizing the significance of size-selective uptake by organisms.
... The GIT was then transferred to the bottle samples for the digestion process. The GIT samples of each O. marmorata individual were then added by the potassium hydroxide (20%) for alkaline digestion, about three times the sample volume (Foekema et al., 2013;Rochman et al., 2015). The samples were then incubated at room temperature (≈ 27°C) for 14 days to let the organic matter of the sample digested. ...
... Plastics that enter seas and oceans are converted to macroplastics, mesoplastics, and microplastics following chemical and biological reactions, including solar degradation, biodegradation, etc. (Jambeck et al., 2015). Due to the small size (1 µm to 5 mm) and global occurrence in coastal-marine waters (Alimba and Faggio, 2019;Amelia et al., 2021;Fatema et al., 2023;González-Ortegón et al., 2022;Napper et al., 2021;Sutton et al., 2016), microplastic (MP) are readily available to different aquatic biota in all water columns (Foekema et al., 2013;Mathalon and Hill, 2014). ...
Fish inhabiting various trophic levels are affected differently as the presence of microplastic (MP) in the water column and their ingestion by fish varies. Walking catfish (Clarias batrachus) inhabits the bottom of the water bodies. To understand the effects of MP, we exposed C. batrachus to two types of MP - polyethylene terephthalate (PET) and low-density polyethylene (LDPE) for 60 days. After exposure, hematological indices, mainly red blood cells and hemoglobin levels decreased, and white blood cells increased significantly compared to the control group (p<0.05). A significant increase in the levels of blood urea and glucose was observed, and serum glutamic pyruvate transaminase and serum glutamyl oxaloacetic transaminase activity remained elevated (p<0.05). Histopathological examination of the liver, kidney, intestine, and gills showed morphological alterations. Moreover, MP exposure caused growth retardation (p<0.05) in C. batrachus. Widespread pollution of water bodies by MP may impose serious ecological risks to bottom-feeding fish in Bangladesh.
... The number of plastic particles per fish was 1-15 pieces (Lusher et al., 2013). MPs intake of marine fish captured in the wild (benthic and pelagic fish) from the north sea (Foekema et al., 2013) and the north-eastern Atlantic (Neves et al., 2015). Eastern pacific ocean (Rochman et al., 2015), and the English Channel (Lusher et al., 2013) was recorded in field trials. ...
Micro (nano)plastics (MNPs) are pollutants of worldwide concern for their ubiquitous environmental presence and associated impacts. The higher consumption of MNPs contaminated commercial food can cause potential adverse human health effects. This review highlights the evidence of MNPs in commercial food items and summarizes different sampling, extraction, and digestion techniques for the isolation of MNPs, such as oxidizing digestion, enzymatic digestion, alkaline digestion and acidic digestion. Various methods for the characterization and quantification of microplastics (MPs) are also compared, including μ-Raman spectroscopy, μ-Fourier transform infrared spectroscopy (FTIR), thermal analysis and Scanning electron microscopy with energy-dispersive X-ray spectroscopy (SEM-EDX). Finally, we share our concerns about the risks of MNPs to human health through the consumption of commercial seafood. The knowledge of the potential human health impacts at a subcellular or molecular level of consuming mariculture products contaminated with MNPs is still limited. Moreover, MNPs are somewhat limited, hard to measure, and still contentious. Due to the nutritional significance of fish consumption, the risk of exposure to MNPs and the associated health effects are of the utmost importance.
The marine finfish and crustaceans contribute immensely to human nutrition. Harvesting marine food‐fish to meet the global demand has become a challenge due to reduction of the fishery areas and food safety hazards associated with increased pre‐harvest and post‐harvest contaminations. The causes of low fish availability and contaminations were reviewed following the published literature from 2000 to 2023. The marine fish yields are stressed due to spread of contaminants triggered by rising sea temperatures, transport of microorganisms by marine vessels across the oceans, anthropogenic activities leading to increase in the toxic microorganisms, and the entry of toxic chemicals and antibiotic residues into the seawater through rivers or directly. Processing adds pyrogenic chemicals to foods. The hazardous materials may accumulate in the food‐fish, beyond tolerance limits permitted for human foods. While the research and control measures focus on minimizing the hazards due to pathogenic microorganisms and chemicals in market fish, there is less discussion on the unhealthy changes occurring in the oceans affecting the quantity and quality of food‐fish, and the origins of microbial and chemical contaminations. This review examines the factors affecting availability of wild food‐fish and increased contaminations. It aims to bridge the knowledge gaps between the spread of hazardous agents in the marine environment, and their effects on the food‐fish. Meeting the future human food security and safety through marine fish and fish products may need marine cage farming, introduction of genetically modified high yielding food‐fish, and cultured contaminant free finless fish muscles as options.
Microplastics are plastic debris smaller than 5 mm in size. In recent decades, the issue of microplastics contamination in marine organisms from the marine environment has gained more attention. This study focuses on the occurrence of microplastics in the gastrointestinal tract (GIT) of the crescent perch (Terapon jarbua). Sixty-two crescent perch were collected from four locations in Malaysia: Sungai Besar and Kuala Selangor on the west coast of Peninsular Malaysia, Kuantan on the east coast of Peninsular Malaysia, and Mukah in East Malaysia. Microplastics were found in the GIT in 82% of the samples with a mean value ranging from 1.46 ± 0.60 to 2.25 ± 1.26 particles/ind. Microplastics contamination in samples from Mukah was significantly higher than in samples from Kuala Selangor. The increased number of ingested microplastics could be attributed to the higher levels of microplastics contamination present in the coastal waters of Mukah due to the anthropogenic activities taking place there. The extracted particles were predominantly fibres, followed by fragment, and film. The microplastics ingested by crescent perch were primarily blue and black. µ-FTIR tests showed that the most common polymers found in crescent perch were rayon, polyethylene terephthalate, and polyethylene. The findings from this study provide initial evidence that microplastic contamination is emerging as a threat to crescent perch and the Malaysian water ecosystem. Further investigations into microplastics contamination in fish in Malaysia are required, as microplastics exposure to fish can induce adverse effects on the species and the food web.
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The oceanic convergence zone in the North Pacific Subtropical Gyre acts to accumulate floating marine debris, including plastic fragments of various sizes. Little is known about the ecological consequences of pelagic plastic accumulation. During the 2009 Scripps Environmental Accumulation of Plastics Expedition (SEAPLEX), we investigated whether mesopelagic fishes ingest plastic debris. A total of 141 fishes from 27 species were dissected to examine whether their stomach contents contained plastic particles. The incidence of plastic in fish stomachs was 9.2%. Net feeding bias was evaluated and judged to be minimal for our methods. The ingestion rate of plastic debris by mesopelagic fishes in the North Pacific is estimated to be from 12 000 to 24 000 tons yr–1. Similar rates of plastic ingestion by mesopelagic fishes may occur in other subtropical gyres.
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Twaite shad Alosa fallax (12–48 cm total length) from the Gulf of Gdansk feed on Mysids: Mysis mixta, Neomysis integer, and fish: Sprattus sprattus, Osmerus eperlanus, and Pomatoschistus sp.. In the stomachs of A. fallax there also occur Hydrobia sp., Diptera and small stones, particles of wood and plastic. The food of inshore twaite shad measured from 12 to 21 cm centered on M. mixta. Fish are the main prey for A. fallax from the class length 22–31 cm from the Vistula River mouth and for all shads longer than 32 cm.
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Predators face decisions about which prey to include in their diet in order to maximize fitness. The foraging tactics used to capture prey and the resulting profitability of prey influence these decisions. We present the first evidence of prey-dependent foraging tactics and prey profitability in a free-ranging pinniped. We studied 39 adult male harbour seals Phoca vitulina at Sable Island, Nova Scotia using an animal-borne video system. Each male wore the camera system for 3 d during which 10 min video samples were recorded every 45 min from 06:00 h, resulting in approximately 3 h of videotape per male and a total of 1094 capture attempts of identified prey. Males foraged mainly on sand lance Ammodytes dubius and flounders (Pleuronectids), but salmonid and gadoid fishes were occasionally pursued. Foraging tactics differed among and within prey types based on differences in prey behaviour. Sand lance was both a cryptic prey, when in the bottom substrate, and a conspicuous schooling prey. Seal swimming speed, handling time and capture success differed between cryptic and conspicuous sand lance. The highest capture success and handling time was recorded for flounders. Estimated profitability, i.e. net energy intake per unit time, also differed with prey type and prey size. Our results suggest that diet selection may have important implications on the foraging energetics of pinnipeds.
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The diet of the large pelagic fish, the southern opah Lampris immaculatus was examined along the Patagonian Shelf in the Falkland Islands region. Stomachs were available for 69 fish collected in 1993 and 1994. Surprisingly, this fish had a relatively narrow range of prey items. The single most frequent prey item was the onychoteuthid squid Moroteuthis ingens (predominantly juveniles) which was eaten by 93% of the fish. The other important prey were the loliginid squid Loligo gahi, the myctophid fish Gymnoscopelus nicholsi and the southern blue whiting Micromesistius australis. There was no evidence of larger individuals of L. immaculatus ingesting larger individuals of any of the 4 main prey species. An unexpected finding was the relatively high incidence of plastic ingestion (14 % of fish). The plastic came from a variety of sources including food, napkin and cigarette wrappers and various pieces of plastic line and straps used in securing boxes. In several instances, there was evidence of feeding on fishing boat discards. The findings reveal a significant impact of plastic pollution in this region of the Southwest Atlantic.
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Results show that the weight of cod (Gadus morhua) stomach contents sampled in the North Sea varies significantly within 24 h. To determine whether feeding varied with time, over 1100 cod stomachs were collected around the clock between 7 and 18 May 1984 in two areas in the central North Sea thought to be representative for feeding studies. Here we investigate temporal feeding patterns based on the analysis of stomach-content data, using generalized additive models (GAMs). Results show significant variation of content weight and indicate morning and evening peaks. The relative peak importance differed between and within areas. We propose that differences are due to diet composition, namely, prey size and diel availability. Cod fed primarily on molluscs, mainly ocean quahog (Cyprina islandica), crustaceans, sandeels (Ammodytes spp.), haddock (Melanogrammus aeglefinus), herring (Clupea harrengus), and several flatfish species. In one area, the diet was dominated by fish, relatively large prey that perform diel vertical migration, and in the other by invertebrates, smaller prey that are digested faster. The diel pattern was more pronounced where invertebrate prey were dominant. Generalisation of results and implications for predation-mortality estimates based on data from the North Sea Stomach Content Database, used to implement multispecies models in the region, are discussed.
This study analyses data from over 20 000 haddock stomachs collected during the 1981 and 1991 Stomach Sampling Projects of the North Sea. Sampling was within the framework of the Multispecies Virtual Population Analysis (MSVPA) for fisheries stock assessment. In 1981 stomachs were collected to calculate input feeding parameters from main predators. During 1991 the sampling exercise was repeated to test stability of the parameters in the region. We investigate stability of haddock stomach content weight between years accounting for ontogenic, spatial and temporal variations within the scope of the survey resolution. Analysis using generalized linear and additive models is performed for weight of the stomach content including and excluding empty stomachs and also for proportion of stomachs without food. Results indicate that haddock stomach contents varied significantly between years, quarters and North Sea roundfish areas. Content weights were overall higher in 1981 than in 1991. In 1981 levels were high from spring to fall and in 1991 mostly in spring. During both years levels were lowest in the central North Sea and in winter. Most of the deviance in modelling the stomach weight is explained by the length of the predator. Stomachs sampled in 1981 were most frequently empty in spring and those sampled in 1991 in winter. In both years, proportions decreased with fish length except in winter when levels increased. Proportion of empty stomachs was highest in the central region of the North Sea. Most of the proportion variation is explained by quarterly fluctuation. Variation of content weight can be related to prey composition found in the stomachs. High stomach contents are generally associated with high contribution of fish prey to the total stomach content, mainly sandeels. We propose that sandeels were more vulnerable to predation in 1981 than in 1991 due to colder temperatures.
During 1974 to 1978 population dynamics of the harbour seal population in the Dutch Wadden Sea have been studied. Frequent aerial surveys provided data upon the size of the population. During boat trips information about the age composition was obtained by measuring track widths. These data have been used in a simulation model to calculate the birth rate and the initial juvenile mortality.It was found (1.) that the initial juvenile mortality in the Dutch population is higher than that in Schleswig Holstein; (2.) that pup production in the Dutch population is low compared to the population in Schleswig Holstein if the ratio adult females to males in the Dutch population is supposed to be equal to that in Schleswig Holstein, or that mortality amongst adult females in the Dutch population is higher than in Schleswig Holstein; (3.) that the number of subadults in the Dutch population is relatively high compared to a stable population (Schleswig Holstein) and that apparently immigration from elsewhere occurs; (4.) that the reproductive rate was higher or the juvenile mortality lower during 1974 to 1978 than in the preceding decennium.
Domestic chickens Gallus domesticus were fed polyethylene pellets to test whether ingested plastic impairs feeding activity. When food was temporally limited, plastic-loaded birds ate less than control birds, apparently as a result of reduced gizzard volume. When given food ad libitum, plastic-loaded birds also ate less and grew slower than did control birds. It is concluded that ingested plastic reduces meal size and thus food consumption when plastic reduces the storage volume of the stomach. This reduced food consumption may limit the ability of seabirds with large plastic loads to lay down fat deposits, and thus reduce fitness.
It has been speculated that marine microplastics may cause negative effects on benthic marine organisms and increase bioaccumulation of persistent organic pollutants (POPs). Here, we provide the first controlled study of plastic effects on benthic organisms including transfer of POPs. The effects of polystyrene (PS) microplastic on survival, activity, and bodyweight as well as the transfer of 19 polychlorinated biphenyls (PCBs), were assessed in bioassays with Arenicola marina (L.). PS was pre-equilibrated in natively contaminated sediment. A positive relation was observed between microplastic concentration in the sediment and both uptake of plastic particles and weight loss by A. marina. Furthermore, a reduction in feeding activity was observed at a PS dose of 7.4% dry weight (DW). A low PS dose of 0.074% increased bioaccumulation of PCBs by a factor 1.1 - 3.6, an effect that was significant for ΣPCBs and several individual congeners. At higher doses, bioaccumulation decreased compared to the low dose, which however, was only significant for PCB105. PS has statistically significant effects on the organisms' fitness and bioaccumulation, but the magnitude of the effects was not high. This may be different for sites with different plastic concentrations, or plastics with a higher affinity for POPs.