Emerging pollutants represent one of the main environmental concerns; they are defined as new contaminants produced by modern society that are not routinely monitored, but cause adverse ecological effects. Today, more than 1000 emerging pollutants (e.g. nanomaterial, microplastics, surfactants, pharmaceuticals and PCBs, pesticides, amongst many others) have been reported in the European aquatic environment. The InTO project will address the combined effects of two emerging pollutants, UV-filters and nanoplastics, on marine bacteria, the most abundant organisms on Earth that are key players of the biogeochemical balances of our planet and are at the heart of bioremediation processes.
Similarly as with micro and nanoplastics pollution, organic UV-filters, which are used in a wide range of cosmetics and personal care products (PCPs), have also been recently identified as ubiquitous contaminants in coastal waters. Those active ingredients are recognised of emerging concern to our oceans due to their persistence, as related to their chemical properties, large production volumes, and their bioaccumulation and toxic effects on marine organisms. Several chemicals – including oxybenzone, octinoxate, octocrylene, octisalate, avobenzone and homosalate – have been identified as being toxic for the environment, as they enhance oxidative stress, affect the immune response, cause coral bleaching, have genotoxic effects and are endocrine disruptors which can, affect fecundity and reproduction in fishes. While recent publications have emphasised the detrimental impact of UV-filters on marine ecosystems, so far there has not been any initiative aimed to address this issue either on a national or international level across the EU. Cosmetics represent a huge market of 10 billion euros in the UK (European Commission 2015), offering a significant incentive, to assess the effects and impacts of these types of emerging pollutants in our oceans.
Although microbeads of polyethylene plastic, which are used in cosmetics and in PCPs (as for e.g. in cleaning products and toothpastes), were banned in 2015 in USA, and then in January 2018 in the UK, micro and nanoplastics remain a major contaminant found in marine (surface and deepwater) and freshwater environments. Microplastics, as well as nanoplastics, can associate with phytoplankton and thus become transferred to higher trophic levels of the food chain. Previous studies demonstrated that several aquatic organisms are negatively affected by microplastics. Nanoplastics not only directly affect aquatic organisms but also adsorb other organic contaminants, such as UV-filters, producing a ‘combined’ pollution with potentially synergistic toxic effects.
The InTO project aims to unravel, for the first time, the combined toxicity effects of these types of emerging anthropogenic pollutants on microbial communities. How these pollutants affect the microbial population structure, regulate their physiologies, and impinge on species interactions in their natural environment are questions of immediate urgency. The PhD student will investigate for the first time the interactive effects of UV-filters and micro/nanoplastics on bacterial models (mock communities) as well as complex natural microbial communities.
The InTO project targets the development of an original interdisciplinary approach combining a novel high-resolution quantitative metaproteomics method with standard biogeochemistry approach. The complementary of skills and combined experience of the Stirling and Heriot-Watt groups in the field of ecotoxicology and marine microbiology strengthen the likelihood of project success and impact. The skills and techniques that the PhD student will use in this project will include: (i) Strategies for sampling of surface seawater during research cruises, including from coastal-based field trips; (ii) Water sample processing techniques (e.g. filtration for recovery of microbial communities and fixation for subsequent analyses); (iii) Lab work using widely-used roller-bottle experimental setup to simulate surface ocean conditions. This approach will allow various treatments with different chemicals, as well as different consortia of marine bacteria to identify which microorganisms are the most significantly impacted by both pollutant types. (iv) Biochemical and geochemical data analysis (e.g. analysis of EPS, DIC, DOC & TEP concentrations in seawater from field samples and during experiments); (iv) DNA/RNA extraction, and metagenomics (vi) Quantitative metaproteomics approach with subsequent bioinformatics analysis to acquire information on the structure and functions of the microbial communities.
This project is part of the Scottish Universities Partnership for Environmental Research (SUPER) Doctoral Training Partnership (DTP) and PhD students will get additional interdisciplinary training through this partnership.
Please send a cover letter, along with academic transcripts and CV to Sabine Matallana Surget at [email protected]
Two references should be provided by the deadline.
Candidates should have (or expect to achieve) a minimum of a First Class Honours degree in a relevant subject, e.g. Biotechnology, Molecular Biology, Marine/Environmental Ecology, and/or Microbiology. Applicants with a minimum of a 2:1 Honours degree may be considered provided they have a Distinction at Masters level. Applicants with degrees in other subjects are invited to discuss their qualifications with the principal supervisor (Sabine Matallana-Surget). A masters-level degree is an advantage.
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