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SOUTHAMPTON SOLENT UNIVERSITY

A comparative study of the spatial distribution of marine microplastics in the Solent area and East Anglia. The study of Microplastics in marine sediments Aldous Rees, Jean-Pascal Beecroft, Rory Hill and Georgie Frary 3/1/2012


Contents page List of Figures and Graphs

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List of Tables

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Abstract

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Acknowledgements

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1. Introduction 1.1 Background microplastics 1.2 Background investigation 1.3 Hypothesis

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2. Method 2.1 Data collection 2.2 Data analysis 2.3 Retrieval rate experiment 2.4 Limitations and problems 2.5 Risk Assessment

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3. Results 3.1 Graphs 3.2 Statistical tests

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4. Discussion 4.1 Levels of microplastic found 4.2 Statistical tests 4.3 Retrieval experiment 4.4 Potential routes of microplastic to beaches – Longshore drift 4.5 Potential routes of microplastics to beaches – Tides 4.6 Future changes to experiment and future of microplastic

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5. Conclusion 6. References

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Appendix 1

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Appendix 2

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Appendix 3

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Appendix 4

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List of Figures and Graphs Figure 1 - Location maps for each area surveyed

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Figure 2 – Image showing measuring of a transect down beach

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Figure 3 – Model of transect layout on beaches

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Figure 4 – Shape classification of microplastics

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Graph 1 – Retrieval rate experiment

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Graph 2 – Microplastic distribution along transect lines

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Graph 3 – Shapes of microplastics found

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Graph 4 – Box and whisker diagram

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List of tables Table 1 – Beaches surveyed

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Table 2 – Potential sources in each area

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A comparative study of the spatial distribution of marine microplastics in the Solent area and East Anglia.

Article info Keywords Microplastics, Essex Coast, Norfolk Coast, Southampton Water, Poole Bay

Abstract: Microplastics are pieces of plastic less than 5mm in size. They have become common in the marine environment in recent years within the water column and in beach sediments. All studies conducted thus far have found microplastics. This study looked at the levels of microplastic within estuarine sediments and beach sediments at a number of locations within Southampton Water, Poole Bay, the Norfolk coast and the Essex coast. 20 beaches were surveyed with three transect lines being used on each beach. Sediment samples were taken from high water, mid water and low water. The microplastic was floated out of the sediments using super saturated saline solution and examined under a microscope. All of the 20 beaches surveyed had plastic present, with 160 out of the 174 samples having plastic within them. The most common shape was fibres, which is thought to come from clothes. This study showed that marine microplastics are wide spread but more research is still needed to show the true distribution.

Acknowledgements: The authors would like to thank Dr Paul Wright for guidance and support throughout the project. We would also like to thank all those that helped with data collection and processing. Finally like to thank Kevin Thatcher and Polly Schoolcraft for allowing us use of the laboratory and using up all their sodium chloride and Petri dishes and the support they gave us during the project.

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1. Introduction 1.1 Background microplastics Microplastics are pieces of plastic under the size of 5mm. They were first identified as a problem in the 1970s (Frais et al 2010). There are two main sources of microplastic: larger pieces of plastic being broken up by waves and sunlight, from industrial processes and sewage works (Thompson et al 2004 and Browne et al 2011). Fibres make up most of the plastic found in the marine environment. An experiment by Browne et al (2011) collected waste water from a washing machine and this research showed that a piece of clothing can shed 1900 bits of polymer fibres per wash. The majority of these particles then enter into water courses. More clothes are worn in winter, so more washes occur meaning higher fibre levels area released during the winter period (Browne et al 2011). They cause many problems in the marine environment as many animals ingest them. The effects on these animals are not yet properly understood and very little research has been carried out on the spatial distribution of marine microplastics (Murray and Cowie 2011 and Fendall and Sewell 2009). Little is known about the amount of microplastics compared to macro plastics as it is harder and more time consuming to collect the data. Another major source of microplastics apart from washing are facial cleaners; originally organic materials were used such as almond husks or pumice, but more recently plastic beads have been used, due to their small size they get through waste water treatment plants and end up in the oceans. Recent research has shown that they are one of the main sources of microplastics in the oceans and fibres make up most of the plastic in sediments (Fendall and Sewell 2009 and Browne et al 2011). Anthony (2011) looked at where plastics are used in the marine environment, 18% of which come from the fishing industry. Marysia (2009) tries to come up with solutions to microplastic in the marine environment by identifying the main sources and then identifying ways to limit them, such as better public awareness and better filters. Microplastics have an impact on marine life, as they ingest plastic thinking it is food which either blocks up their guts or deprives them of nutrients they would gain from other food sources. Murray and Cowie (2011) carried out research on the effects to decapods crustacean Nephrops norvegicus and 83% of the nephrops sampled contained plastics in their guts. This study shows that a large number of crustaceans are consuming plastics. The true extent and 4


how far up the food chain plastics travel is as yet unknown. Some indications show it could even affect humans (Gordon 2000). Microplastics can also release Persistent Organic Pollutants (POPs), these are organic compounds that are resistant to environmental degradation. They include PAH and PCBs (Noren 2010). This leads to further problems for marine life and the wider environment (Zaffl et al 2011). A number of investigations have been carried out on the amount of microplastics present in marine sediments across the world. Every beach sampled seems to have some microplastics within the sediment. An investigation carried out off the Belgian coast (Claessens et al 2011) looked at sediment cores to see the build up over time, the problems with this method are that sand is disturbed through tides and tourist activity. The paper did highlight this; the samples seemed to show an increase over time. All of the samples collected were found to contain microplastics. The levels were high for studies in the area, only investigations in India near to a ship breaking yard yielded higher results to date. In Belgium the concentrations of microplastics were higher in coastal waters and a trend appeared to show that as plastic production increases in general the levels found on the beaches as microplastics also increase. An investigation of the Portuguese coast (Frias et al 2010) surveyed two beaches both near to ports and a wide range of plastic was found in the sediment samples. Investigations off the Singapore coast (Ng and Obbard 2006) showed large amounts of plastic were present. It is thought that this plastic comes from Asian countries such as India. The data were collected from beaches and also the water column, both were found to have microplastics present. Corcorana et al (2009) surveyed 18 beaches in Hawaii and these all contained plastic. Studies by Zarfl and Matthies (2010) indicated that plastics have reached the Arctic and it is thought ocean gyres transport plastic to the region. A survey in Malta carried out by Turner and Holmes (2011) on sandy beaches of which there are only a small percentage in Malta and a few rocky shores. Most of the plastics found were at the backshore, rather than the swash zone. On the rocky shores, pellets were found embedded in tar deposits. What the currents investigations show is that large amounts of microplastics are present, but there is no standardised method to collect data. This makes it hard to compare results from different investigations. In the future a method that works and can be used worldwide need to be created, (NOAA 2008). These investigations also show that more research is needed to better understand the spatial distribution of microplastics.

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1.2 Background investigation This investigation studied the levels of microplastics present within sediment at a number of different sites in the Solent area and East Anglia (See table 1 and figure 1). This will show the spatial distribution of marine microplastics and will help to determine how much of a problem they are in the marine environment. A number of different beaches and mudflats were surveyed. The Solent area was split into two groups: estuarine sediments within Southampton Water and beach sediments on South coast in Poole Bay and Christchurch Bay between Bournemouth and Milford on Sea. Data were also collected on the Norfolk and Essex (see table 1). Table 1: Survey areas and beaches/mudflats sampled Southampton water

Northam Chessel bay Nature reserve Netley Hythe Warsash

South Coast between Bournemouth and Milford on sea Bournemouth Boscombe

Norfolk coast

Essex coast

Mundesley Old Hunstanton

Walton Frinton on Sea

Frairs Cliffe Avon Milford on Sea

Caistor on Sea Sea Palling East Runton

Clacton on Sea Brightlingsea East Mersea

1.3: Hypothesis There will be more plastic on beaches than estuaries, due to it being transported out of river systems by tides and currents and onto the beaches. The majority of the plastics found will fibres, as this is mainly what other investigations have found.

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Figure 1: Maps to show sample areas (Edina Digimaps 2012 and Broadland storage 2012).

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2. Method 2.1 Data Collection A total of four areas were investigated for the concentration of micro-plastics. These were: Southampton Water and estuaries Poole Bay North Norfolk coast Essex coast

Figure 2: Measuring a transect line on Boscombe beach (Author, 2011).

At each area 5 different beaches were visited and at each beach a total of 9 sediment samples were collected. On each beach, three transect lines were taken: one on the right, one in the centre and one on the left (see Figure 2 and 3). The difference between the transects varied on each beach depending on the total length. For example on Bournemouth beach the samples were 300 metres apart whereas on Chessel beach they were only 50 metres. This method was adapted from Thompson et al (2004) who sampled at high water on a number of beaches. Ng and Obbard (2006) used a different method by collecting 0.5 metres from the tide line. At each transect, the position was logged by GPS and the length of the transect was recorded. 3 sediment samples were taken down the transect line: at the mean high water mark, halfway down the transect and at the mean low water mark. Sediment was collected using a trowel which was cleaned after each sample, and the sample was placed in a sterile sample bag, sealed and labelled. This was done to avoid the contamination of the sample.

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Figure 3: Diagram showing an example beach with transect lines.

Mean Low Water

Transect 3

Transect 1

Transect 2

Mean High Water

2.2 Data analysis The samples were then analysed in a laboratory to establish the levels of microplastic present within them. Firstly the samples were taken out of the sample bags and placed into trays and if the samples were damp they were left to dry out. The samples were then coned and quartered to ensure that a representative part of the sample was used in analysis. A 250 gram portion of the coned and quartered sediment was then mixed in a beaker with 250 millimetres of super saline solution (distilled water with Sodium Chloride added to the saturation point). This was 540 grams per 1.5 litres. The sample was mixed for 30 seconds and then left to stand until the sediment had settled. The time varied between samples, muddy sediments took several hours to settle whereas stony or sandy samples only took minutes. Mixing with a super-saline solution would cause any plastic within the sample to float to the surface as it has a lower density. Thompson et al (2004) suggested this method. His study may have used a different technique for dissolving Sodium Chloride in water, as the same levels of salinity (1.2kg NaCl l-1) could not be achieved in this study. The level of salinity suggested by Thompson isn’t possible, as the maximum saturation of Sodium Chloride in water is 360 grams of Sodium Chloride per litre of water. Another explanation for this could be a printing error.

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Once the sediment had settled, the top layer of water was extracted using a pipette. This was then filtered using a funnel and Whatman GF/A filter paper. The rest of the water was then also poured through the filter. The pipette was used so that any plastics floating on the surface would be gathered. The filter paper was then placed in a dish, labelled and left to dry. The remaining sediment was disposed of. Once the sample had dried, it was examined under a microscope. This was done in a systematic way so that the whole sample was viewed. Any objects that weren’t salt crystals, sediment or organic matter were measured using a ruler and their characteristics, such as colour and shape were recorded (see Figure 4). The potential sources in each area were identified (see Table 2).

Figure 4: Microplastics classification system (authors 2011).

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Table 2: Potential sources of plastics each region Source Classification Natural

Southampton Water

Industrial

Shipping activity: Marchwood Military port, Fawley Oil terminal, Southampton Port. Industrial park, Scrap yard, Fishing activity Sewage works @ St Denys, Woolston, Hamble Le Rice, Marchwood, Hythe, Eastleigh, Lower Swanwick, Milbrook

Fishing activity,

Debris off roads, Boat yards, Marinas, Outfall pipes

Debris off roads, Holiday parks, Marinas, Boat yards, Outfall pipes

Residential

Infrastructure

Rivers, Itchen, Test and Hamble, Beaulieu and Lymington

Poole and Christchurch Bay River Stour, Avon and Mude. Passford Water

Sewage works @ Bournemouth, Ensbury (edge of Bournemouth), Lymington, East Boldre,

Essex

Norfolk

River Colne, Chelmer, Blackwater, Crouch, Roach Felixstowe port, Fishing activity

River Great Ouse, Breydon water, Burn

Sewage works @ Colchester, Maldon, Clacton and Holland on Sea, Fingringhoe, Tollesbury, West Mersea, Salcott, Brightlingsea, Great Wigborough Debris off roads, Boat yards, Outfall pipes, Marinas

Sewage works @ Mundesley, Hunstanton, Caistor on Sea, Corton, Great Yarmouth, Cromer, Heacham, Kings Lynn

Fishing activity, Kings Lynn port, Bacton gas works, Kings Lynn Chemical works

Tourists Debris off roads Outfall pipes

2.3 Retrieval rate experiment This experiment aimed to determine if the type of sediment had an effect on the amount of microplastic retrieved. This was of interest as it could have an effect on the overall results of this investigation. Three types of sediment were used in this investigation: sand, shingle and mud. These were chosen as they were the main types of sediment encountered over the course of this investigation. Ten brightly coloured microplastic beads were placed in 250g of each sediment, 250ml of super saline solution was added and the mixtures were stirred to suspend the sediment in the solution. These were then left to settle out. Once the sediment and solution had settled, the beads were visually identified and removed from each test sample. If not all beads had been retrieved, the samples were re-suspended and left to settle once again, and the process was repeated (see graph 1 and Appendix 3).

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Graph 1: Retrieval rate experiment

Retrieval rate (%)

Retrieval rate of microplastic beads from different types of sediment 90 80 70 60 50 40 30 20 10 0 Sand

Shingle

Mud

Sediment type

Graph 1 shows that 80% of microplastic beads inserted into the sand and shingle were retrieved, whereas only 40% of beads inserted into the mud were retrieved. 2.4 Limitations and problems During sample collection, there were sometimes difficulties in defining where the beach began and ended. This was especially found in Poole Bay. On Friars Cliff, for example, the beach had many access points and stretched for a long distance; the transects were taken down the beach at the access point and then 100 metres on either side. Another problem found whilst sample collecting was the tide, although the method states that a sample was collected at the mean low water mark, this was only true for a number of beaches. This occurred especially on the North Norfolk beaches where the inter-tidal zone is long and relatively flat. This caused the tide to come in quickly and so at each beach, the low water sample was taken further up the transect. To try and counter this, the sampling started an hour and a half before high water and finished around an hour and a half after. In the first few laboratory sessions the levels of salt being dissolved was too much, due to Thompson’s method. Once this was changed it worked better as an error meant it wasn’t possible to dissolve that much salt in water.

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For the sample processing, the filtering method was changed during the investigation. At first the filter paper was in a Coors Buchner funnel, but it was found that the filter paper would lift and consequently water and micro-plastics were potentially flowing down the edges. This was then changed to the filter paper being folded into a conventional conical funnel. Another flaw in the method was that when pouring particularly silty sediments, the sediment could end up on the filter paper and this then made it hard to distinguish any plastics through the microscope. 2.5 Risk assessment When collecting the samples there was always more than one person present and at least one person had a mobile telephone. Due to the nature of the collecting, the tidal times were known and the height of the water was observed. All of the collectors wore sensible footwear. At Chessel bay, towards the low water mark there was thick mud. Here a platform was used to stand on and on one transect; the final sample was collected a little way from the low water mark due to the nature of the ‘beach’. In the laboratory, whilst working with the super-saline solution, laboratory coats and safety glasses were worn.

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3. Results 3.1 Graphs Graph 2: Distribution of microplastics along transect lines at each site

Graph showing the distribution of Microplastics along transect lines at sample sites 35 Microplastic Count

30 25 20 15 10

High Water

5

Mid Water

0

Low Water

Estuary

Location Type

Open Sea beach

Graph 2 - Graph showing the distribution of Microplastics along transect lines at sample sites. Anomalies: Low water at Warsash shows a significantly higher count of microplastics than other sites, as does high water at Walton on the Naze. Due to tidal restrictions, there is only data for high water at Milford.

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Graph 3: Frequency of microplastics shapes

Number

Graph showing the total frequency of shapes of Microplastics across all sample sites 700 600 500 400 300 200 100 0

639

22

52

Rounded

Irregular

17 Fibre

Straight edged

Microplastic type

Graph 3 - Graph showing the total frequency of shapes of Microplastics across all sample sites. This shows the total number of microplastics found and their shape. The total found was 730 pieces. As it’s clearly shown in the graph, fibrous plastics were by far the most common making up 87.5% of all found. The next highest was irregular pieces accounting for 7.1% of all plastic found. Appendix 2 shows the raw data with the totals for each individual sample site.

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Graph 4: Box and Whisker plot

Box and Whisker Diagram showing spread of data 35

Number of Microplastics

30 25

q1

20

Min Mean

15

Max 10

q3

5 0 Estuaries

Beaches

3.2 Statistical tests The standard deviation results for the two areas:

Standard Deviation Coefficient of Variation

Estuaries Beaches 6.93 6.17 66.80%

47.80%

T-test P = 0.027 The T Test demonstrates the validity of the hypothesis. If the probability (P), result is lower than 0.05 then the hypothesis can be accepted. The hypothesis can be viewed on Page 7. The P result shows that there were more Microplastics found on Open water beaches then those in an estuarine setting. This result is however insignificant.

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4. Discussion 4.1 Levels of microplastic found Microplastics can cause many problems in the marine environment and are a major source of marine pollution (Murray and Cowie 2011). There are a number of sources of microplastics: the breakdown of macroplastics already present in the environment, or from industrial and domestic uses (Noren 2011). This investigation looked at microplastic levels within estuaries and on beaches on the South Coast in comparison to the East Coast. Every beach sampled had microplastic present. Out of 174 transect samples, 160 contained microplastics. The shape classification data shows that irregular and straight edged pieces made up 9.4% of the total plastic count. This type of microplastic is more likely to have stemmed from the breakdown of macroplastics. The data shows that a greater percentage (10.7%) of this type of microplastic was found in a beach setting in comparison to estuarine environments (6.3%) (see graph 3). This could be due to wave action being more prominent on open beaches than in estuaries, breaking down macroplastics at a greater rate. Rounded microplastics made up 3% of the total plastic count. These are likely to have resulted from the industrial use of plastic beads as stock for the production of plastic goods. Other potential sources include facial scrubs and beauty products with plastic beads to rejuvenate and revitalise (because you’re worth it). In estuaries, these microplastics made up 4.1% of the total plastic count, and 2.5% of the total plastic count on beaches. The levels may be higher in an estuarine setting due to the higher frequency of sewage and water treatment works in the locality (see Table 2 and appendix1 and 2). In studies by Thompson (2004) and Browne et al (2011) these were relatively common after fibres. Most of the plastic found in this study were of a fibrous nature (87.5%). Research has shown that most fibrous microplastics result from domestic sources such as the breakdown of polymers from clothes in washing machines. Macroplastics such as ropes, fishing lines and nets can also breakdown into fibrous microplastics (Browne et al 2011). These are generally polypropylene, nylon and polyester (Thompson 2004 and Browne et al 2011). On beaches, fibres made up 86.6% of the total plastic count, and 93.8% in estuaries. This could be again due to the sewage and water treatment works in the areas (see table 2), discharging water from washing machines.

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4.2 Statistical tests The Box and Whisker diagram (see Graph 4) shows how spread the data is away from the mean. From this it can be seen that the range of plastic count for the two different regions is not that different (Estuaries – 31, Beaches -29). However the boxes, which show 50% of the data, are quite different. For the estuarine data, the box spans from 6 to 12 items found whereas for the beach data it covers from 9 to 19. This difference means that for estuaries, the data in more concentrated around the mean. This implies that for the samples collected in locations on an estuary there is more consistency on the number of pieces of microplastics found. However as the mean for open water beaches is higher, the total plastic found on each beach is greater. Standard Deviation demonstrates the distribution of the data around then mean. If the standard deviation result is lower than the data is more closely grouped to the mean. The results show that the estuarine beaches had a value of 6.93 and the open water beaches had a value of 6.17. This result contradicts the results of the box and whisker test. However the negative of using this test is that it doesn’t take the sample size into account. But this doesn’t mean that the data/ statistical tests are wrong. A conclusion can be gathered from this: The open water beaches had a greater number of plastics found on each site in comparison to estuarine beaches. But, the amount of microplastics found on estuarine beaches was more consistent. This could have several implications to the distribution of microplastic: More is found in open water however its distribution is not consistent with more being found in some locations compared to others. Within an estuarine environment, less is found but the amounts are more consistent. Explanations for this pattern could be explained by the sources of microplastics shown in Table 2 (Page 11). This shows how many of the possible sources are situated in the estuarine environment, such as the sewage works on the Itchen, a key source of microplastics originating from washing machines etc. This would cause a greater concentration of microplastics as seen in the standard deviation result. The reason there were averagely fewer pieces found could be due to the retrieval rate as discussed in the next section. Coefficient of Variation is similar to Standard Deviation but is not influenced by the sample size and range; this makes it useful in this study. However the results in this case came to the same conclusions as the standard deviation tests so nothing new can be interpreted.

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The final test used was the T Test; this measures how the means of two groups are statistically different from each other. The result of the T Test gives a probability of achieving the result. If this probability value is below 0.05 then it can be stated that there is a significant difference between the two means. The result for the microplastic data was a probability value of 0.027, this is below 0.05 therefore there is a significant difference between the two means. 4.3 Retrieval rate experiment The retrieval rate investigation has shown that there is a greater retrieval rate of microplastics from sand and shingle than there is from mud (see graph 1 and appendix 3). This could be due to the fact that sand and shingle are looser and therefore less dense, so sink back to the bottom of the solution at a lesser rate than mud, allowing more time for the microplastics to float to the top and be retrieved. In contrast to this, as mud is more dense than sand and shingle, it would sink to the bottom of the solution faster, therefore trapping the microplastic beads at the bottom and preventing them from rising to the top. This could have effects on this experiment, as samples taken from areas of mud (such as Warsash) could actually have had less than half of their actual microplastic content counted. The majority of estuarine sediments collected were of a finer particle size, so could potentially have a lower retrieval rate than the beach sediments. 4.4 Potential transport routes for microplastic to beaches - longshore drift Microplastics could reach the beaches via Longshore drift with the sediment being deposited on the beaches. This would indicate that plastic is also present in the water column. Studies in a number of regions have shown this (Thompson et al 2005 and Browne et al 2011). The sediment cells for each area show how the microplastic could reach the beach sediments. The main sediment cell for Poole bay and the Solent has boundaries between Portland bill in the west and Selsey Bill in the east. This is split into sub cells with their own sedimentary budgets. On the East coast the sediment cell boundaries are from the River Humber to the Thames, with sub cells around Clacton on Sea and the Norfolk Coast around Happisburgh (see appendix 4) (Wallingford et al 2002 and Solent Forum 1996). In Poole and Christchurch Bay there seems to be a gradual rise in sample one from Bournemouth to Milford on Sea. This could be due to long shore drift taking sediment and plastics within it down the coast. It is hard to see this trend properly as not a full data set is available for Milford on Sea. The other beaches don’t seem to follow this trend. This could be due to the Norfolk and Essex 19


coast being less built up or that long shore drift has little effect on the movements of microplastics. Even though this is hard to prove, it is clear that microplastics are being brought to beaches via the sea and land based sources, so longshore drift will play some part in where the microplastic is deposited. More investigation into this would help to determine if this is the case (see Appendix 4). 4.5 Potential transport routes for microplastic to beaches - Tides Tides have a similar effect to longshore drift moving water and sediment around the coast. Their biggest influence is within the estuarine environment where they replenish the water every six hours. This tidal action could also be used to transport microplastics. The estuaries studied in this report: Southampton Water and the River Colne and Blackwater both have strong tidal conditions with a mesotidal range in Southampton and a macrotidal range on the Rivers Colne and Blackwater (Posey 2010 and Townsend 2008). In both cases the tidal system is ebb dominated; this is when the out going tide has a higher velocity. In relation to transportation of Microplastics, this tidal condition will cause plastic, which may have sourced further up the estuary, to be taken seawards. This process could be used to explain the larger number of plastic found at Warsash which was the furthest seaward sampling site taken on Southampton Water. 4.6 Future changes to experiment and the future of microplastic If this study were to be replicated in the future, improvements which could be made include the use of cotton only clothing so that there is a smaller chance of sample contamination when out in the field furthermore the use of laboratory coats when participating in the experiment will again reduce the risk of contamination. For a wider range of results, a larger sample area could be used. The study could have extended to the Isle of Wight and the other side of Portsmouth. This would increase reliability of the average and also create a larger view of microplastic distribution. Different types of sample areas can be used which can then be compared to each other, for example the use of sandy beaches compared to shingle beaches, or mud flats compared to salt marshes.

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The study can progress further by not just sampling sediment from beaches but from the water column of the beaches and in rivers and estuaries. This would show if there is a correlation between microplastic offshore and onshore. Methods to stop microplastics getting into the environment need to be implemented. This can be done through beach cleanup operations, better filtering methods of wastewater and finer filters on washing machines. Fines could be given to persistent offenders.

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5. Conclusions This report investigated the levels of microplastics on Estuarine and Open water beaches along the South and East Anglian coasts. Microplastics were present on every beach sampled but there were discrepancies between Estuaries and Open water. The results and subsequent statistical tests confirmed the hypothesis: That more plastics would be found on Open water beaches in comparison to estuarine. Whilst the total microplastics found on open water beaches was greater; the individual beaches had a greater variance in amounts found in comparison to estuarine beaches. This was proven in the box and whisker which showed that the results for estuarine beaches were grouped closer around the mean. Microplastics are a major source of pollution in the marine environment, the true extent of their distribution is not fully understood. Further studies using similar methods are required to help further understand the distribution of microplastics both in the UK and on a global scale. Further studies are also required to investigate the environmental impacts of microplastics. Due to the large level present plans need to be put in place to limit the levels of microplastics, as preliminary studies have shown them to be harmful to the environment. This could be improved through better filtering methods in wastewater treatment plants or better controls on beach litter. These will help to control the levels of microplastic released into the marine environment.

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6. References Anon, 15 October 2010, Appendix C, baseline processes, Essex and Suffolk SMP, available online: http://www.tendringdc.gov.uk/NR/rdonlyres/E15F3091-9B2B-4D74-B61A41DAF3167B3F/0/AppendixCSMPDevelopmentDraftFinalversion.pdf last accessed on 28 February 2012 Anthony L., A., 2011, Microplastics in the marine environment: Marine Pollution Bulletin, v. 62, p. 1596-1605. Broadland storage, 2012, Specialists in secure storage for Caravans, Boats & Trailers, available online: http://broadlandcaravanstorage.co.uk/ last accessed on 30th January 2012 Browne M, Crump P, Niven S J,Teuten E, Tonkin A, Galloway T and Thompson R, September 2011, Accumulation of Microplastic on shorelines worldwide: sources and sinks, Environmental science and technology, available online: http://www.plasticsoupfoundation.org/wp-content/uploads/2011/08/Browne_2011-ESTAccumulation_of_microplastics-worldwide-sources-sinks.pdf last accessed on 28 January Claessens, M., Meester, S. D., Landuyt, L. V., Clerck, K. D., and Janssen, C. R., 2011, Occurrence and distribution of microplastics in marine sediments along the Belgian coast: Marine Pollution Bulletin, v. 62, p. 2199-2204. Corcoran, P. L., Biesinger, M. C., and Grifi, M., 2009, Plastics and beaches: A degrading relationship: Marine Pollution Bulletin, v. 58, p. 80-84. Fendall, L. S., and Sewell, M. A., 2009, Contributing to marine pollution by washing your face: Microplastics in facial cleansers: Marine Pollution Bulletin, v. 58, p. 1225-1228. Frias, J. P. G. L., Sobral, P., and Ferreira, A. M., 2010, Organic pollutants in microplastics from two beaches of the Portuguese coast: Marine Pollution Bulletin, v. 60, p. 1988-1992. Gordon R.P, June 2000, The Vertical and Horizontal Distribution of Microplastics in the Caribbean and Sargasso Seas along the W-169 Cruise Track, May-June, 2000, available online: http://people.oregonstate.edu/~gordonr/Ryan_Gordon/DownloadsRyan_Gordon_files/Gordon_SEA_2000.pdf last accessed on 29 January 2012 Marysia, 2009, Environmental risks of microplastics, available online: http://www.cleanupsa.co.za/Images/Environmental_Risks_Microplastics.pdf last accessed on 2 November 2011 Murray, F., and Cowie, P. R., 2011, Plastic contamination in the decapod crustacean Nephrops norvegicus (Linnaeus, 1758): Marine Pollution Bulletin, v. 62, p. 1207-1217. Ng, K. L., and Obbard, J. P., 2006, Prevalence of microplastics in Singapore’s coastal marine environment: Marine Pollution Bulletin, v. 52, p. 761-767.

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NOAA, 2008, Proceedings of the International Research Workshop on the Occurrence, Effects, and Fate of Microplastic Marine Debris, available online: http://marinedebris.noaa.gov/projects/pdfs/Microplastics.pdf last accessed on 2 November 2011 Norén, F, 2008, Small plastic particles in coastal Swedish waters, N-Research report, Available online: http://www.kimointernational.org/Portals/0/Files/Small%20plastic%20particles%20in%20Sw edish%20West%20Coast%20Waters.pdf last accessed on 28 January 2012 O’Brine, T., and Thompson, R. C., 2010, Degradation of plastic carrier bags in the marine environment: Marine Pollution Bulletin, v. 60, p. 2279-2283. Posey V, 2 March 2010, Essex and south Suffolk SMP, appendix c, available online: http://publications.environment-agency.gov.uk/PDF/GEAN0110BREI-E-E.pdf last accessed on 7 March 2012 Redfern, 24 June 2005, Coastal defences in Norfolk, available online: http://www.geocases1.co.uk/printable/Coastal%20defences%20in%20Norfolk.pdf last accessed on 28 February 2012 Solent Forum, 1996, Sediment and tidal currents in the Solent, Map, available online: http://www.geodata.soton.ac.uk/solent/gifs/st5.gif last accessed on 21 February 2012 Scopac, 2011, Poole and Christchurch Bay, Sediment transport, available online: http://www.twobays.net/our_shoreline.htm last accessed on 21 February 2012 Thompson R, Olsen Y, Mitchell R, Davis A, Rowland S,. John A, McGonigle D and Russell A, 2004, Lost at sea: where is all the plastic, Sceince direct Townsend I, 2008, A CONCEPTUAL MODEL OF SOUTHAMPTON WATER, DEFRA, available online: http://www.estuar-guide.net/pdfs/southampton_water_case_study.pdf last accessed on 12 January 2012 Turner, A., and Holmes, L., 2011, Occurrence, distribution and characteristics of beached plastic production pellets on the island of Malta (central Mediterranean): Marine Pollution Bulletin, v. 62, p. 377-381. Wallingford. H, Haskoning . P and D’Olier . B, August 2002, Southern North Sea Sediment Transport Study, Phase 2, available online: http://www.sns2.org/Output%20files/EX4526SNS2-main%20report-ver2.pdf last accessed on 21 February 2012 Zarfl, C., Fleet, D., Fries, E., Galgani, F. o., Gerdts, G., Hanke, G., and Matthies, M., 2011, Microplastics in oceans: Marine Pollution Bulletin, v. 62, p. 1589-1591. Zarfl, C., and Matthies, M., 2010, Are marine plastic particles transport vectors for organic pollutants to the Arctic?: Marine Pollution Bulletin, v. 60, p. 181

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Appendix 1 – Raw data showing total counts of microplastics for each site

Site

High Water

Mid Water

Low water

Northam

12

12

10

Hythe

13

5

5

Warsash

5

10

32

Netley

19

6

12

East Mersea

6

8

6

Chessel Bay

6

7

1

Brightlingsea

16

7

20

Boscombe

2

11

6

Friar's Cliff

2

23

20

Bournemouth

6

22

11

Avon

9

13

15

Sea Palling

12

22

18

Caistor on Sea

22

15

21

East Runton

12

12

12

Mundesely

23

17

23

Old Hunstanton

17

7

11

Clacton on Sea

19

11

6

Frinton on Sea

18

9

8

Walton on the Naze

31

8

9

Milford

16

25


Appendix 2 – Classified raw data Site

Fibre

Northam

34

Hythe

22

Warsash

45

2

Netley

36

1

East Mersea

14

3

6

Chessel Bay

7

3

3

Brightlingsea

39 Total:

197

Straight edged

Rounded

Irregular

1

1

1 3

9

11

Boscombe

15

1

1

Friar's Cliff

39

1

1

Bournemouth

35

2

2

Avon

37

Sea Palling

41

1

2

Caistor on Sea

57

1

East Runton

30

Mundesely

54

Old Hunstanton

26

4

1

Clacton on Sea

34

1

1

Walton on the Naze

28

Frinton on Sea

30

Milford

16

1

3

2 7

2 1

2

18 4

Total:

442

14

13

41

Total Count

639

17

22

52

87.5%

2.3%

3.0%

7.1%

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Appendix 3 – Retrieval rate experiment Sediment type Sand Shingle Mud

Retrieval rate (%) 80 80 40

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Appendix 4 - Sediment cells, to show possible transport routes of plastics to the sediment 1A: Southampton Water

This shows the movement of sediment and tidal streams within the Solent. This shows how plastic could be deposited in the sediments, within Southampton Water. Currents also come into Southampton Water from the Solent, which could bring in more plastic. To the west of the Isle of Wight tides and sediment flows out of the Solent, towards Poole Bay, contributing more to this area (Solent Forum 1996). 1B: Poole Bay and Christchurch Bay This shows the sediment moving from Bournemouth along to Hurst point. This is a sub cell between Portland Bill and Selsey Bill. It shows the regions plastic could be transported from and suggests a reason why levels increase towards Milford on Sea. The sediment moves along the coast to Milford on Sea, meaning more plastic should be present (scopac 2011).

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1C: Norfolk and Essex Coast

This shows the sediment transport on the East coast, it moves from Essex towards Norfolk (Wallingford et al 2002). There are also sub cells around Clacton and on the Norfolk coast at Happisburgh. This shows that half of the sediment moves towards the Thames while the other half towards The Wash, the divide is at Happisburgh.

1D: Sub cell for Essex coast

This diagram of sediment transport shows sediment moves down the Essex coast towards the Thames estuary, showing the movement around the sample areas (Anon 2010).

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Journal test