Microplastics are widely dispersed through the marine environment. Few studies have assessed the long-term or historic prevalence of microplastics, yet acquiring such data can inform their distribution, transport and the environmental risks posed. To quantify the distribution and polymer types temporally, sediment cores were collected from >2000 m water depth in the Rockall Trough, North Atlantic Ocean. As hypothesized, a significant negative trend was observed in the frequency of microplastics with increasing sediment age, however there was an increase in polymer diversity. Microplastics were pervasive throughout the sediment analysed (10 cm depth), yet lead-210 (210Pb) activities were confined to the upper 4 cm, indicating this layer to be ~150 years old and thus the presence of microplastics far exceed the production of modern plastic. A number of mechanisms, including sediment reworking, could redistribute microplastics vertically. Additionally, microplastics abundance was significantly correlated with sediment porosity, suggesting interstitial transport via pore waters.

Although evidence suggests the ubiquity of microplastics in the marine environment, our knowledge of its occurrence within remote habitats, such as the deep sea, is scarce. Furthermore, long term investigations of microplastic abundances are even more limited. Here we present a long-term study of the ingestion of microplastics by two deep-sea benthic invertebrates (Ophiomusium lymani and Hymenaster pellucidus) sampled over four decades. Specimens were collected between the years 1976–2015 from a repeat monitoring site >2000 m deep in the Rockall Trough, North East Atlantic. Microplastics were identified at a relatively consistent level throughout and therefore may have been present at this locality prior to 1976. Considering the mass production of plastics began in the 1940s - 50s our data suggest the relatively rapid occurrence of microplastics within the deep sea. Of the individuals examined (n = 153), 45% had ingested microplastics, of which fibres were most prevalent (95%). A total of eight different polymer types were isolated; polyamide and polyester were found in the highest concentrations and in the majority of years, while low-density polystyrene was only identified in 2015. This study provides an assessment of the historic occurrence of microplastics on the deep seafloor and presents a detailed quantification and characterisation of microplastics ingested by benthic species. Furthermore these data advance our knowledge on the long-term fate of microplastic in marine systems.

Validation of the separation of secondary microplastics from sediment using numerous brine solutions in a rapid, reproducible, single stage technique.

This study reports plastic ingestion in various fish found from coastal and offshore sites in Scottish marine waters. Coastal samples consisted of three demersal flatfish species (n=128) collected from the East and West coasts of Scotland. Offshore samples consisted of 5 pelagic species and 4 demersal species (n=84) collected from the Northeast Atlantic. From the coastal fish sampled, 47.7% of the gastrointestinal tracts contained macroplastic and microplastic. Of the 84 pelagic and demersal offshore fish, only 2 (2.4%) individuals from different species had ingested plastic identified as a clear polystyrene fibre and a black polyamide fibre. The average number of plastic items found per fish from all locations that had ingested plastic was 1.8 (±1.7) with polyamide (65.3%), polyethylene terephthalate (14.4%) and acrylic (14.4%) being the three most commonly found plastics. This study adds to the existing data on macroplastic and microplastic ingestion in fish species.

Municipal effluent discharged from wastewater treatment works (WwTW) is suspected to be a significant contributor of microplastics (MP) to the environment as many personal care products contain plastic microbeads. A secondary WwTW (population equivalent 650 000) was sampled for microplastics at different stages of the treatment process to ascertain at what stage in the treatment process the MP are being removed. The influent contained on average 15.70 (±5.23) MP·L(-1). This was reduced to 0.25 (±0.04) MP·L(-1) in the final effluent, a decrease of 98.41%. Despite this large reduction we calculate that this WwTW is releasing 65 million microplastics into the receiving water every day. A significant proportion of the microplastic accumulated in and was removed during the grease removal stage (19.67 (±4.51) MP/2.5 g), it was only in the grease that the much publicised microbeads were found. This study shows that despite the efficient removal rates of MP achieved by this modern treatment plant when dealing with such a large volume of effluent even a modest amount of microplastics being released per liter of effluent could result in significant amounts of microplastics entering the environment. This is the first study to describe in detail the fate of microplastics during the wastewater treatment process.

Les combinaisons de phtalocyanine mono-substituees sont particulierement interessantes dans la technologie des pigments, en effet, comme additifs, ils s'adsorbent fermement a la surface des pigments, empechant ainsi la formation de cristaux. C'est seulement recemment que des amido-phtalocyanines de cuivre substituees ont ete fabriquees par voie de synthese en plusieurs etapes. On vient de reussir non seulement a raccourcir la synthese de trois amido-phtalocyanines de cuivre alkyles, mais encore a purifier les mono-produits a l'aide de la chromatographie a couche mince et a les caracteriser au moyen de la spectrometrie de masse par le temps de vol. Des premieres etudes prouvent que ces combinaisons mises en oeuvre dans des peintures pigmentees au CuPc ameliorent le comportement a l'ecoulement, la dispersibilite et le pouvoir colorant.

Substituted amido copper phthalocyanine ( CuPc ) derivatives are being investigated as additives in pigment systems. Propylamido, dodecylamido and octadecylamido copper phthalocyanine have been prepared by reaction of the corresponding amine hydrochloride and the mono (carboxamide) of copper phthalocyanine in a melt reaction. The carboxamide of CuPc was prepared by reaction of phthalic acid and trimellitic acid in a urea melt; reagents were selected to maximize the mono-substituted product. The mono (carboxamide) of CuPc as prepared therefore contained CuPc and a statistical mixture of other CuPc carboxamides; however, the formation of the alkyl derivatives allowed purification by high-temperature thin layer chromatography, which gave good separations, and characterization with MALDI-TOF mass spectrometry. Initial investigations show that these alkyl amido CuPcS , when used in CuPc pigment compositions for paints improve the dispersion rheology and dispersibility/colouring strength.

Langmuir films have been prepared using pure C60 and arachidic acid mixed with C60 in the ratio of 1 : 1 and 4.2 : 1. Langmuir–Blodgett (LB) films were then deposited on a variety of substrates with Y-type deposition being observed. Films containing bilayers of arachidic acid alternating with both single and double monolayers of C60 were prepared. The structure of the arachidic acid component in the mixed films was investigated by grazing-incidence FTIR spectroscopy and was shown to be similar to that in an LB film of pure arachidic acid. The absence of structural disruption in the presence of C60 provides strong evidence for an ordered alternant arrangement of fullerenes and arachidic acid in the films.

Thin films of organic materials are increasingly being used for technological applications. In this study two methods of thin film production, Physical Vapour Deposition (PVD) and Solution Casting on a water surface, have been used to prepare thin films of organic materials for investigation by Transmission Electron Microscopy. The polycyclic aromatic compounds perylene and quaterrylene were evaporated under high vacuum onto the (001) of a freshly cleaved crystal of KCl. Substrate temperature was shown to play a important role in determining the crystallinity and morphology of the thin film produced. An optimum substrate temperature was found at which deposited crystals were smooth, formed large domains and did not undergo re-evaporation from the substrate. Lattice images were obtained for the quaterrylene and some image processing was attempted. The second class of compounds studied were a range of octasubstituted phthalocyanines that were synthesised. These compounds are potential one dimensional conductors since they stack in a to face manner allowing good n-orbital overlap. The compounds prepared were all based on the octa-dodecyloxy-phthalocyanine unit and were the metal free, copper, silicon-dihydroxy and polysiloxane derivatives. Films of these compounds could be prepared by allowing a chloroform solution of these compound to evaporate on a water surface. Information was obtained by electron diffraction and by lattice imaging. The most common packing arrangement was for a stack of molecules to lie parallel to the water surface. The molecules in the stack could be either tilted or perpendicular to the stack. Only the copper derivative showed any evidence of lying flat on the water surface. The unusual packing of these molecules was explained in terms of the strong hydrophobic interaction between the paraffin side chains and the water surface.