The consequences of microplastics spreading from surfaces made from molded rubber granules has a negative impact on our ecosystems, plants, and other living organisms. As our understanding of these negative environmental impacts grows, the need to shape and enforce effective measures to reduce this spread also increases. This creates a challenge for the political environmental management on both a national and municipal level. This study investigates the condition of Swedish municipalities and the possibilities they have to take effective measures to reduce the spread of microplastics in facilities that use molded rubber granules, in a time when both knowledge and experience of molded rubber granules is still limited. The study also examines whether the municipality’s participation during the forming of new environmental policies impacts the final outcome. The theory is based on implementation and participitation in management and politics. The results are based on interviews with representatives from nine Swedish municipalities, all geographically spread out and of varying size. Even if the accountable party at the municipalities admitted that their surfaces made from molded rubber granules spread microplastics, they lacked knowledge on the spread’s environmental impact. Both lack of sufficient resources and possibility to take effective action due to politically conflicting goals, confirmed several of the challenges connected to participation and implementation within politics. The study finds that the lack of knowledge on the environmental impact of molded rubber granules, the municipalities’ limited resources and the conflicting goals between the requirements of accessibility and environmental requirements affect the municipalities’ possibilities to implement measures through an environmental policy. Through an increased cooperation between state and municipalities during the forming and implementation of environmental policies the goal fulfillments would likely improve. / Effekterna av mikroplastspridning från ytor av gjutet gummigranulat påverkar både ekosystem, växter och levande organismer negativt. I takt med att förståelsen för mikroplasters negativa miljöpåverkan ökar växer behovet av att utforma och vidta effektiva åtgärder för att minska mikroplastspridningen. Detta utmanar den politiska miljöstyrningen på både statlig och kommunal nivå. Studien undersöker svenska kommuners förutsättningar för att vidta åtgärder som motverkar spridning av mikroplast från anläggningar med gjutet gummigranulat. Denna studie undersöker också hur kommuners deltagande vid utformning av nya miljöpolicys kan påverka måluppfyllnaden. Den teoretiska ramen utgörs av genomförande och deltagande inom politik och förvaltning. Resultatet baseras på intervjuer med representanter för nio geografiskt spridda svenska kommuner av varierande storlek. De ansvariga på kommunerna var medvetna om att deras ytor av gjutet gummigranulat sprider mikroplast men saknade djupare kunskap om miljöeffekterna av mikroplastspridningen. Otillräckliga ekonomiska resurser och politiska målkonflikter är några av de utmaningar som är kopplade till deltagande och genomförande inom politik och förvaltning. Kommunernas inställning till alternativa material såsom gjutet korkgranulat och åtgärder genom granulatfällor var positiv. Studien finner att bristen på kunskap om gjutet gummigranulats miljöeffekter, kommunernas resursbegränsningar och målkonflikten mellan tillgänglighetskrav och miljökrav påverkar kommunernas förutsättningar att implementera åtgärder genom en miljöpolicy. Med ett ökat deltagande genom samverkan mellan statlig och kommunal nivå vid utformning och implementering av miljöpolicys skulle måluppfyllnaden sannolikt förbättras.

Mikroplast är ett begrepp som förekommer allt mer frekvent i media och medför stor förvirring kring var det kommer ifrån och varför det är skadligt. Naturvårdsverket har listat de sju största faktorerna till emission av mikroplast i Sverige, där hushållstvätt av syntetfiber är en utav dem. Mikroplast är små plastfragment (1 nm- 5 mm) och härstammar inte bara från syntetfiber, utan från bland annat däckslitage, allmän nedskräpning och fiskeverktyg. Vid hushållstvätt sprids partiklarna via avloppsvattnet, genom reningsverk och hamnar till slut i havet där de drar till sig miljöfarliga kemikalier och skadar vattenlevande organismer. Den här studien utreder textilföretags miljökommunikation angående mikroplast gentemot kund samt vad det finns för råd och direktiv från organisationer och myndigheter för textilföretag att tillgå vid dess generering av mikroplast. Studiens ambition är att kunna förmedla samlade riktlinjer till textilföretag som kan appliceras till deras verksamhet. Studien stöds utav RISE IVF och MinShed projektet och kommer genomföras med hjälp av litteratur-, enkät-, och intervjustudier. Resultatet som tagits fram genom uppsatsen visar att textilföretag generellt inte kommunicerar mikroplast gentemot kund. Det här beror på den, än så länge, bristfällig forskning som finns tillgänglig angående emission av mikroplast. Textilföretag upplever att de inte har tillräckligt med information för att ta långsiktiga beslut som kan förbättra dess hantering av mikroplast. Avsaknaden av standardiserade testmetoder över hur mycket olika syntetfiber fäller är det som textilföretag upplever saknas. Resultatet visar också att organisationer och myndigheter överlag inte ger några råd och direktiv till specifikt textilföretag. Utifrån de resultat som presenteras från det underlag som grundat sig från litteratur-, enkät-, och intervjustudier, kan författarna dra slutsatsen att rapporten inte kommer bidra med rekommendationer till textilföretag. Författarna uppmanar till vidare forskning inom ämnet, främst angående utveckling av filter i tvättmaskiner, som skulle kunna hindra mikroplast att spridas ut i havsmiljön via avloppsvattnet. / Microplastic waste is something that is featured more and more frequently in media today. There is a lot of confusion, due to the focus in the media, on what microplastic waste actually is and in what way it is harmful to the environment. The Environmental Protection Agency has listed the seven biggest sources to microplastic shedding and it shows that household laundry of synthetic fibers is one of them. Microplastic waste, or microplastics, are small plastic fragments (1 nm- 5 mm) and originate not only from synthetic fibers, but from tire wear, general plastic waste and fishing tools. During household laundry, the synthetic fibers shed microplastic that travels through the wastewater and sewage treatment plants before it finally ends up in the ocean where they have the potential to attract hazardous chemicals and damage aquatic organisms.    This study examines textile companies environmental communication regarding microplastics towards their customer and what kind of guidelines different organizations, institutes and authorities offer to textile companies regarding their generation of microplastics. The ambition of the study is to gather overall guidelines to textile companies that can be applied to their businesses. The study is supported by RISE IVF and the MinShed project and has been accomplished by literature-, questionnaire-, and interview studies. The outcome of the study shows that textile companies generally do not communicate about microplastics to their customer. This is due to the, so far, inadequate research regarding microplastic shedding. Textile companies experience that they do not have enough information to make long-term decisions that can improve their microplastic management, since there is no standardized test methods for fabrics available. The result also shows that organizations and authorities generally do not provide guidelines specific to textile companies. Based on the result from the study, the writers will not accomplish to gather guidelines to textile companies regarding microplastic management. The writers request further research on microplastics, primarily regarding the development of filters in washing machines, which could prevent microplastics from spreading out into the marine environment via the wastewater.

Synthetic polymers are one of the most significant pollutants in the aquatic environment, because of abilities such as buoyancy and extreme persistency. Serious effects are expected from so-called microplastics (particle size <5 mm) that are reported in rivers, lakes as well as the ocean and that accumulate in sediments worldwide. In this thesis the abundance of microplastics in river shore sediments in the Rhine-Main area of Germany was studied. Therefore, a new method was developed that is based on a sodium chloride density separation with subsequent destruction of natural debris, and identification of the plastic particles by microscopy or Fourier transform infrared spectroscopy (FTIR). Using the improved density separation, microplastics were separated from river shore sediments of 12 sites originating from the river Rhine, the river Main, and the stream Schwarzbach. Large amounts of microplastic particles of up to 1 g kg-1 or up to 4000 particles kg-1 were detected in the shore sediments. The identification by FTIR showed that polyethylene, polypropylene, and polystyrene were the most abundant polymer types in the sediments, covering over 75% of all plastics identified. Transport of microplastics from tributaries to main streams was indicated by the detection of identical pellets in the River Rhine and in the Main mouth. Comparable concentrations detected by sampling one site over a period of two years suggest a constant pollution of the river shore sediments with microplastics. For deeper insights into the sorption process of organic contaminants to synthetic polymers in freshwater systems, batch experiments in synthetic freshwater were conducted to determine sorption kinetics and sorption isotherms for four selected glass state polymers (polycarbonate, poly(methyl methacrylate), polystyrene, and polyvinyl chloride) and six different model substances (carbamazepine, hexachlorocyclohexane (β/γ), 17α-ethynilestradiol, chlorpyrifos, and o,p-dichlorodiphenyltrichlorethane). Sorption to the polymer particles was observed for all contaminants increasing with the KOW values of the contaminants. Because of losses of contaminants in control samples, sorption reaction models could be applied to four out of six contaminants, and isotherms were calculated for three contaminants. Furthermore, influences of the different polymer types used were observed in the experiments. Finally, microplastics separated from sediments were extracted and analyzed by GC/MS and LC-MS/MS using target screening methods and non-target approaches. Different pesticides were identified in the polymer particles, suggesting that microplastics can act as a sink for hydrophobic contaminants. Moreover, several plastic additives such as phthalates or chlorinated flame retardants were identified. For this reason, it is very likely that microplastics act as a direct source for these chemicals in aquatic systems. The results of this thesis stress the urgency for the mitigation of the plastic particles in the aquatic environment.

Mikroplastik (Kunststoff-Partikel < 5 mm) wurde in den vergangenen Jahren vermehrt in verschiedenen marinen Ökosystemen nachgewiesen und erreicht regelmäßig wissenschaftliche und öffentliche Aufmerksamkeit. Es wird als potentielle Gefahr für die marine Umwelt angesehen. Aufgrund der geringen Größe kann Mikroplastik von marinen Organismen mit der Nahrung verwechselt werden und infolge dessen in den Magen-Darm-Trakt gelangen. Ob die so aufgenommenen Partikel zu einer Schädigung der Organismen führen und welche Wirkungsmechanismen dabei eine Rolle spielen, ist derzeit noch nicht umfassend geklärt. In diesem Zusammenhang wird Mikroplastik beispielsweise als Transportvehikel für enthaltene Kunststoffadditive, für adsorbierte persistente organische Schadstoffe sowie für potentiell pathogene Mikroorganismen diskutiert. Für eine Risikobewertung sind in erster Linie zuverlässige Daten über die Mikroplastik-Gehalte in verschiedenen Umweltkompartimenten nötig. Dazu werden geeignete und sichere analytische Verfahren zur Identifizierung und Quantifizierung von Mikroplastik in Umweltproben benötigt. Ziel dieser Arbeit war es bestehende Wissenslücken im Bereich der Mikroplastik-Analytik zu schließen und Möglichkeiten und Grenzen der FTIR- und Raman-Spektroskopie für die analytische Untersuchung von marinen Mikroplastik-Proben aufzuzeigen. Dazu wurde zunächst ein Filtersubstrat entwickelt, das für eine umfassende Untersuchung von filtrierten Mikroplastik-Proben sowohl mittels Transmission FTIR- als auch mittels Raman-Mikroskopie geeignet ist. Des Weiteren wurde Raman Imaging als neuartige Methode zur Identifizierung von Mikroplastik etabliert und hinsichtlich verschiedener Messparameter optimiert. Die Anwendbarkeit dieses neuen Analyseansatzes wurde an realen Umweltproben gezeigt. Beide spektroskopische Verfahren (IR und Raman) wurden anhand von Modellproben und realen Umweltproben miteinander verglichen und validiert. Zusätzlich dazu wurden die spektroskopischen Ergebnisse an ausgewählten Proben mit der thermoanalytischen py-GC/MS-Methode verglichen und beurteilt. Im dritten Teil der Arbeit wurden die Mikroplastik-Gehalte in Sedimentproben aus dem Mündungsbereich der Warnow, einem bedeutenden Zufluss zur Ostsee, bestimmt. Dabei wurden lokale Eintragspfade abgeschätzt sowie Senke von Mikroplastik identifiziert.:1 Motivation und Zielstellung 2 Wissenschaftlicher Hintergrund 3 Experimenteller Teil 4 Ergebnisse und Diskussion 5 Zusammenfassung und Ausblick Anhang Literaturverzeichnis Abbildungsverzeichnis Tabellenverzeichnis Danksagung Publikationsliste Versicherung

<p>The overarching theme of this research is about environmental microplastic pollution, and how much various entities are willing to sacrifice economically to obtain a cleaner environment. To gauge such willingness, this research utilizes various economic measures that have been widely used, albeit with novel modifications. The focus of this research is on stated preferences about microplastic pollution. The topic of microplastics is still very novel, and market players on the demand side or on the supply side have yet to provide products that deal with this new pollutant. This lack has necessitated the need for stated preference research. This research delves into this novel environmental problem from various viewpoints.</p> <p> Chapter 1 of this research is about how much the US adult population is willing to sacrifice to obtain an environment that is less impacted by microplastic pollution. The results show that US adults in general possess a willingness to obtain an environment free from microplastics. However, a sizable minority of US adults do not show such willingness as well. Such results remained true even when information about microplastic pollution were provided to all respondents before preference elicitation. </p> <p> Chapter 2 investigates how much consumers in different countries will diverge about their willingness to pay for seafood that has less microplastic contamination. The countries chosen differed widely in their seafood consumption habits. Thus, it was hypothesized that such differences will lead to contrasts in their willingness to pay for less contaminated seafood. The hypothesis was found to be true but not in the way that was expected. The results show that frequent consumers of seafood had less willingness to pay when compared to others, although in whole all consumers showed willingness to avoid microplastics in their seafood. </p> <p> Chapter 3 makes use of the same data as Chapter 2 but looks at possible reasons for the disparity in responses besides factors explored in Chapter 2. Chapter 3 focuses on the cultural differences to explain the differences in behavior. To do so, it utilizes the Value-Belief-Norm theory widely employed in past research but modifies it to account for a form of hypothetical bias. The research delves into the relationships between many factors of interest that affect environmentally friendly consumption behavior and the findings show that a certain cultural tendency is central to such behavior, at least for microplastics. </p> <p> The research has done its best to research into the economic relationship between microplastic contamination of the environment and how much various individuals are willing to sacrifice to obtain an environment that is less impacted by such pollution. The findings here show that there is room for improvement in the way the microplastic pollution problem is being handled. However, in all settings the results show that a sizable majority want to be less impacted by microplastic pollution, a key takeaway for all interested parties.</p>

Plastic, including microplastic, is a common product in the society today and is starting to be more common in oceans where it can stay for a long time. Microplastic is defined usually in the size range five millimeter and smaller and together with the important Chao Phraya river in Bangkok, Thailand, the main subject of this paper is described. More clearly, the aim of this paper is to provide a first-hand quantification of microplastics flowing into the Chao Phraya River. Samples were taken at upstream, middle and downstream locations in the river with a pump-system and were then analyzed in a lab. The result showed an increasing load of microplastic entering the river from Bangkok, for example the result for size range five to one millimeter showed a six times increase of microplastic between the upstream and downstream point. / Plast, däribland mikroplaster, är en vanlig förekommande produkt i samhället idag och börjar bli allt vanligare i hav där det också kan stanna ett långt tag efter att det hamnat där. Mikroplaster definieras oftast med storleks intervallet fem millimeter och mindre och tillsammans med den viktiga floden Chao Phraya i Bangkok, Thailand, är huvudämnet för denna studie beskriven. Mer tydligt, målet för denna studie är att förse en första kvantifiering av mikroplaster som flödar in till Chao Phraya floden. Prover togs på platser som var uppströms, i mitten och nedströms på floden och sedan analyserades dessa prover i ett laboratorium. Resultatet som framkom visade på ökande belastning av mikroplaster i floden från Bangkok, exempelvis visade resultatet för storleks intervallet fem till en millimeter på en sex gånger ökning av mikroplaster mellan uppströms platsen och nedströms platsen. Ökningen som troligen kommer från innerstaden kan bero på olika faktorer såsom väder, stadens avfallshantering och användningen av engångsprodukter som är av plastmaterial. Således påvisar detta vikten av, bland annat, en fungerande avfallshantering.

Mikroplastik (1–1000 µm) kommt praktisch überall in der Umwelt vor, aber immer noch ist die Iden-tifizierung und Quantifizierung eine anspruchsvolle und zeitintensive Aufgabe. Erste analytisch Metho¬den beginnen sich zu etablieren, jedoch sind die benötigten Instrumente komplex und der Probendurchsatz für Routineuntersuchungen in den meisten Fällen noch zu gering. Diese Arbeit widmet sich zunächst dem Potenzial der Nahinfrarot (NIR)-Spektroskopie diese Lücke zu schließen. Exemplarisch wird ein günstiges Verfahren mit großem Probendurchsatz zur Bestimmung von Mikro¬plastik-Gesamtgehalten der verbreiteten Verpackungskunststoffe Polyethylen (PE), Polystyrol (PS) und Polypropylen (PP) in Böden und Kompost entwickelt. Neben der Untersuchung von Mikroplastik-Gesamtgehalten einer Probe ist auch die Charakterisierung individueller Partikel von großer Bedeutung. Die bildgebende Fourier-Transform-Infrarot (FTIR)-Mikrospektroskopie ist hierfür sehr gut geeignet. Allerdings ist es eine Herausforderung Mikroplastik in den aus mehreren Million Spektren bestehenden hyperspektralen Bildern zu identifizieren. Eine schnelle und zuverlässige Mikroplastikerkennung wird hier durch eine explorative Analyse und automatisierte Klassifizierung der Spektren erreicht. Zusammenfassend zeigt diese Arbeit, dass die optische Spektroskopie im mittleren und nahen Infrarot über ihre bisherige Anwendung hinaus ein großes Potenzial besitzen, die Mikroplastik-Analytik kostengünstiger, einfacher und schneller zu gestalten. / Microplastics (1-1000 µm) are ubiquitous in the environment, but their identification and quantification is still a challenging and time-consuming task. The first established methods require complex instruments and the sample throughput is still too low for routine analysis in most cases. This work first addresses the potential of near-infrared (NIR) spectroscopy to fill this gap. A low-cost method with large sample throughput is developed for the determination of total microplastic contents of the common packaging plastics polyethylene (PE), polystyrene (PS) and polypropylene (PP) in soils and compost. In addition to the investigation of total microplastic levels in a sample, the characterization of individual particles is also of great importance. Fourier transform infrared (FTIR) imaging microspectroscopy is well suited for this purpose. However, it is challenging to identify microplastics in hyperspectral images consisting of several million spectra. Fast and reliable microplastic detection is achieved by exploratory analysis and automated classification of the spectra. In summary, this work shows that mid- and near-infrared optical spectroscopy have great potential beyond their current application to make microplastics analysis cheaper, easier, and faster.

The oceans are an essential global resource for all living organisms but especially for us humans. However, year after year we continue to neglect proper recycling of our waste, resulting in litter ending up in our oceans. The majority of said litter comes from single use plastic items. Through fragmentation and erosion, the plastic dissolves  to smaller pieces, once they are no larger than 5 mm theyare classified as micro- and nanoplastics. Little is known about these small plastic particles impact on marine life and marine environment. As a step towards understanding this, the robot PlaCo was created. PlaCo stands for plastic collecting which is exactly what the robot does. With the help of three filters PlaCo gathers marine debris, such as plastic, from the water in which it operates. The filters have decreasing mesh size resulting in the microplastics being caught in the last one. Once emptied, the finds can be examined and logged for future referencing. With the help of a sensor, blockages of the filters can be monitored and if detected, notice will be given to the user through a LED. In order for PlaCo to move forward and for water to travel through the filters, the robot was provided with two DC motors. A microcontroller, Arduino Uno, was used to regulate PlaCo’s functions. The performance of two different sensors, an IR-sensorand an ultrasonic sensor, were investigated as well as the robot's water cleaning capacity. The results indicate that the latter of the two sensors would be preferable due to its high reliability. However, the robot’s water cleaning capacity could not be measured due to the chosen motors not being powerful enough. In future iterations of PlaCo, thiswould need to be rectified. / Globalt sett är världens hav en viktig resurs för alla levande organismer men inte minst för människan. Trots detta fortsätter vi att, år efter år, försumma återvinningen av vårt avfall vilket resulterar i att skräp i stället hamnar i haven. Majoriteten av de sopor som hamnar där är resultatet av förbrukade engångsprodukter i plast. Genom sönderfall och erosion skapas allt mindre och mindre bitar av plast. Detta resulterar i att så kallade mikro- och nanoplaster skapas. De är mindre än 5 mm i bredd och om deras påverkan på det marina djurlivet och den marina miljön vet vi mycket lite om. För att minska kunskapsluckorna och för att få en bättre förståelse för deras påverkan har nu därför PlaCo konstruerats. Med hjälp av tre sorters filter kan PlaCo samla upp marintskräp, så som plast, i vattnet där den arbetar. Filtrens finhet varierar, där det första är mycket grovt medan det sista är fint nog att klara av att samla upp mikroplaster. När PlaCo sedan töms kan mikroplasterna undersökas och dokumenteras. När en tömning behöver göras indikeras detta för användaren med hjälp utav en LED. Roboten är försedd med en sensor som läser av hur fulla filtren är. För att driva PlaCo framåt och för att underlätta filtreringsprocessen är den också försedd med två 6 V DC-motorer. Allt detta styrs med hjälp av mikrokontrollern Arduino Uno. För att uppnå bästa tänkbara funktion hos roboten undersöktes två olika sensortyper, en IR-sensor och en ultraljudssensor. Det visade sig att ultraljudssensorn var betydligt mer pålitlig än IR-sensorn och därför valde man att använda denna. Det var även av intresse att ta reda på hur mycket vatten PlaCo kunde rena per sekund. Tyvärr skulle det visa sig att de valda motorerna inte var kraftfulla nog att driva PlaCo i vattnet. Det är därför något som behöver åtgärdas i en framtida version av PlaCo.

Os grânulos plásticos são encontrados no ambiente marinho e, em função de suas características podem concentrar e transportar poluentes orgânicos. A Enseada de Santos representa um polo de grande importância econômica para o estado de São Paulo, devido à existência do Porto de Santos e do complexo industrial de Cubatão nos seus arredores. Essa região foi escolhida para o desenvolvimento deste estudo por possuir uma grande quantidade de grânulos na superfície arenosa de suas praias. O presente estudo teve como objetivos: (1) avaliar uma proposta metodológica para a coleta de grânulos plásticos, baseada no uso de transectos perpendiculares à linha da água compostos por escavações (amostragens) equidistantes; e (2) analisar a concentração, composição e fontes de contaminação de hidrocarbonetos policíclicos aromáticos (HPAs) nos grânulos coletados em praias arenosas, considerando diferentes escalas espaciais e a influência do tipo de resina que os grânulos são produzidos, bem como o tempo de exposição destes no ambiente. O resultado da avaliação da proposta metodológica determinou o diâmetro do trado que fornece a melhor combinação entre tempo e volume de sedimento coletado, além da confirmação da profundidade de maior ocorrência dos grânulos na coluna sedimentar, bem como a constatação de que transectos tornam-se inviáveis para este procedimento. É sugerido, então, o desenvolvimento de estudos futuros a fim de encontrar o melhor desenho amostral, uma vez que não foi eficaz a realização de transectos, para a amostragem de grânulos plásticos em profundidade. De acordo com os resultados das análises, a concentração e composição de HPAs nos grânulos plásticos variaram de forma expressiva entre os pontos amostrais em uma mesma praia, de forma que, para a obtenção da real variabilidade de poluentes em uma praia, são necessárias coletas em diversos pontos amostrais, a fim de evitar uma equivocada extrapolação dos resultados. As análises dos grânulos coletados em diferentes profundidades no sedimento arenoso indicam resultados semelhantes, com uma alta variabilidade na composição e concentração de HPAs. Entre as resinas, houve diferença na concentração de HPAs (polietileno > polipropileno) e no tempo de exposição, com maiores concentrações nos grânulos mais escuros, ou seja, mais tempo expostos no ambiente. A contaminação na área de coleta é oriunda da mistura de compostos provenientes de fontes petrogênicas e pirolíticas e as análises da potencial toxicidade dos HPAs em grânulos, em geral, indicam um risco iminente aos organismos. São necessários, no entanto, estudos complementares também para a investigação da possibilidade de bioacumulação dos poluentes em organismos. / Plastic pellets are easily found in marine environment and due to its characteristics they may concentrate and bring organic pollutants. Santos bay represents a major economic center for the state of São Paulo because of Santos Port and the Cubatão industrial complex in its surroundings. This place was chosen for the development of the study for the great number of pellets found in the sandy surface of its beaches. This study aimed at (1) evaluating a sampling methodology for plastic pellets based on the use of transects perpendicular to the seawater line and made by diggings equally distant from one another (samplings). It also aimed at (2) analyzing the concentration, composition and sources of polycyclic aromatic hydrocarbons (PAH) contamination on the pellets sampled on sandy beaches, considering different spatial scales and resin kinds which the plastic pellets were made from as well as their exposure time in the environment. As a result of the evaluation of sampling methodology the sampler diameter was defined which provides the best combination between the time and the volume of sampled sediment. Apart from that the depth of the major occurrence of plastic pellets in the sedimentary column was confirmed and it was established that transects are impracticable for this kind of procedure. The development of future studies in order to figure out the best sample design is suggested once the use of transects was not efficient for plastic pellets sampling in depth. According to analyses results the PAHs concentration and composition on the plastic pellets vary largely among sampling sites on the same beach. In order to obtain real pollutant variability on one beach, samples taken from different sampling sites are necessary to avoid a wrong over sizing of results. The plastic pellets analyses taken from different depths in sandy sediment showed similar results to those from the surface with a high variability in PAH concentration and composition. Among the resins there was a difference on PAH concentration (polyethylene > polypropylene) and exposure time, showing larger concentrations on darker pellets, that is longer exposed in the environment. The contamination in the studied area comes from the mixture of compounds from petrogenic and pyrolitic sources and the PAHs potential toxicity in plastic pellets analyses generally reflect an imminent risk to organisms. Complementary studies are also necessary to investigate the possibility of pollutant bioaccumulation in organisms.

Os grânulos de plástico (\"pellets\") no oceano podem adsorver diversas substâncias hidrofóbicas como os poluentes orgânicos persistentes (POPs). Neste trabalho foi avaliada a ocorrência de bifenilos policlorados (PCBs) e diclorodifeniltricloroetano (DDTs) em \"pellets\" coletados em 37 praias de 13 municípios ao longo do litoral paulista, sudeste do Brasil. Os POPs foram extraídos com solventes orgânicos e quantificados por cromatografia em fase gasosa com detecção por captura de elétrons (CG-DCE) e espectrometria de massas (CG/EM). A deposição dos \"pellets\" e a concentração dos PCBs (1,3 - 5.112 ng g-1) e DDTs (14,1 - 1.214 ng g-1) foi maior na Baixada Santista, onde se localiza o maior complexo industrial do país e o maior porto da América Latina, seguido do litoral norte não industrializado e o litoral sul com atividade pesqueira. Os dados de POPs em \"pellets\" deste estudo foram comparados aos publicados anteriormente utilizando grânulos com vários graus de descoloração da mesma área e aos resultados do International Pellet Watch (grânulos amarelados) apresentando concentrações similares e contribuíram para acompanhar o \"status\" de contaminação por POPs na costa do Estado de São Paulo. / Pellets in the ocean can adsorb various hydrophobic substances such as persistent organic pollutants (POPs).This study evaluated the occurrence of polychlorinated biphenyls (PCBs) and dichloro-diphenyltrichloroethane (DDT) adsorbed on plastic pellets. The pellets were collected in 37 beaches of 13 cities, along the São Paulo coast, southern Brazil. The POPs were extracted with organic solvents and quantified by gas chromatograph equipped with electron capture detector (GC-ECD) and mass spectrometer (GC/MS). The deposition of \"pellets\" and the concentration of PCBs (1.3-5,112 ng g-1) and DDTs (14.1 - 1,214 ng g-1) were greater in the Santos Bay, where the largest industrial complex in the country and the largest port in Latin America are located; followed by the non-industrialized north coast and the south coast presenting fishing activity. The POPs data was compared to those previously published using granules with a mixture of several degrees of discoloration from the same area and the results from International Pellet Watch (yellowing pellets). The results indicated concentrations and contributed to monitoring POPs contamination status on the coast of the State of São Paulo.