Alexandra Gulizia
alexandra.gulizia@my.jcu.edu.au
PhD
College of Science and Engineering
Alexandra Gulizia
alexandra.gulizia@my.jcu.edu.au
PhD
College of Science and Engineering
The preparation and characterisation of microplastics containing contaminants
Alex is currently undertaking her PhD (Natural and Physical Science) at JCU, Townsville after successfully completing her BSc Hons (Chemistry) in 2018. Alex's honours project investigated the formation of hydrogels using macroalgae biomass from aquaculture farms for applications in biotechnology and soil science. Alex completed her BSc (Chemistry and Ecology & Conservation Biology) at Monash University, Melbourne.
The preparation and characterisation of microplastics containing contaminants
2019 to 2022
Project Description
This project will aim to understand the leaching behaviors of plasticized microplastics exposed to different environmental conditions. Exposure conditions will include, but are not limited to polymer and plasticiser type, temperature, pH, salinity and UV exposure. They will also examine the formation of biofilms of the surface of microplastics, with the aim to also characterise changes in biofilm communities and subsequent polymer degradation under the aforementioned conditions.
Project Importance
There are increasing studies examining the toxicological effects of contaminated microplastics to marine and aquatic organisms. Results have indicated that plasticised microplastics are toxic both upon ingestion by organisms and when particles are diffused in the environment. However it remains unclear the pathway of exposure- i.e. the leaching behaviors of contaminates from microplastics. This research will help underpin the major exposure pathway to animals, and give more context to research undertaken by marine scientists and toxicologist.
Project Methods
a) controlled preparation of MP's containing contaminates of different w/t%
b) analytical techniques to characterise the microplastics (e.g. GPC, TGA, FTIR, GC/MS...)
c) direct leaching studies of contamianted microplastics
d) controlled formation and characterisation of biofilm composition and abundance using EM and genetic tools to identify microorganism communities.
Project Results
They hope to find the differential leaching/diffusion behaviors/rates of contamiantes from microplastics influenced by variable conditions. Also the differential degradation of polymers based on biofilm communities under variable conditions.
Current results suggests that leaching of plasticiser BPS occurs at different rates. They hypothesize that this is on account of differential interactions/bonding between the polymer matrix and DEHP.
Keywords
Supervised By:
Publications:
(2022) McCormick Mark I., Chivers Douglas P., Ferrari Maud C. O., Blandford Makeely I., Nanninga Gerrit B., Richardson Celia, Fakan Eric P., Vamvounis George, Gulizia Alexandra M. and Allan Bridie J. M.
Microplastic exposure interacts with habitat degradation to affect behaviour and survival of juvenile fish in the field
DOI: 10.1098/rspb.2020.1947
Coral reefs are degrading globally due to increased environmental stressors including warming and elevated levels of pollutants. These stressors affect not only habitat-forming organisms, such as corals, but they may also directly affect the organisms that inhabit these ecosystems. Here, we explore how the dual threat of habitat degradation and microplastic exposure may affect the behaviour and survival of coral reef fish in the field. Fish were caught prior to settlement and pulse-fed polystyrene microplastics six times over 4 days, then placed in the field on live or dead-degraded coral patches. Exposure to microplastics or dead coral led fish to be bolder, more active and stray further from shelter compared to control fish. Effect sizes indicated that plastic exposure had a greater effect on behaviour than degraded habitat, and we found no evidence of synergistic effects. This pattern was also displayed in their survival in the field. Our results highlight that attaining low concentrations of microplastic in the environment will be a useful management strategy, since minimizing microplastic intake by fishes may work concurrently with reef restoration strategies to enhance the resilience of coral reef populations.