1. Influence of Urban Land Use on the Accumulation of Microplastics in Urban Water Bodies
Add supervisors
Supervisors: Vincent Pettigrove
Dave Sharley
Kallie Townsend
Hsuan-Cheng Lu

2. Microplastics Persistence and durability
Increasing in plastic waste globally.
Occurrence has been reported globally.
Ingestion by organisms in environment
Absorption of persistent bioaccumulative and toxic compounds (PBTs), such as organic pollutants and metals.
Why microplastics are important
Brief introduction of the history
Effect on ecosystems

3. Where do microplastics come from?
Primary
Primary microplastics refer to those are in the original form when found, such as microbeads used in many cosmetics and personal cleansers (Napper et al. 2015), virgin resin pellets for plastic manufacture, fibres in textiles (Fendall and Sewell. 2009), and industrial scrubbers used for abrasive blast cleaning (Derraik 2002).

4. Where do microplastics come from?
Secondary
On the other hand, secondary microplastics refer to those derived from the breakdown of large plastic debris due to photo degradation and UV radiation (Ryan et al. 2009).

5. Size classification Minimum size ?
however, there is no consensus about the actual size range of microplastics. At first, researchers defined them as any plastics with diameter less than 5 mm. but the application of 1 mm has gradually increased because it is more close to the concept “micro”. So far, microplastics are only defined their maximum size, but how about the minimum size? The minimum size of microplastics mainly depends on the research objective, sampling and processing methods applied.

6. Marine Estuary Freshwater waterways
What have been done
Marine
Estuary
Freshwater waterways
Sediment or surface water
Urban water bodies, such as wetlands?

7. Microplastics in Constructed Wetlands
Is there any pollution?
What types of microplastics present?
What are the main urban land use generating the pollution?
Lots of macroinvertebrates live in the sediment and they might expose to the contamination of microplastics
What are the sources of microplastics in urban wetlands? Are they produced by residential, industrial etc?

8. Aims
To develop a standard technique to extract microplastics from freshwater environment.
To investigate the occurrence and sources of microplastics in urban environments.

9. Constructed Wetlands key component of stormwater management strategies
Improve water quality - ↓nitrogen, enhance landscape and ecological values, socially acceptable

11. Sediment classification: very fine sand
Industrial Site
Sediment classification: very fine sand

12. Sediment classification: very fine sand
Residential Site
Sediment classification: very fine sand

13. Sediment classification: coarse silt
Mixture Site
Sediment classification: coarse silt

14. How to extract microplastics from samples?

15. Types of plastics and high density solution
Abbreviation
Density (g/cm3)
Polypropylene
Polyethylene PP PE
Ethylene vinyl acetate
EVA
Polystyrene PS
Acrylonitrile butadiene styrene
ABS
Acrylic
Polyester
PES
Polyamide PA
Poly methyl acrylate
PMA
Polyurethane PU
1.20
Sodium chloride
NaCl
Polyvinyl alcohol
PVA
Polycarbonate PC
Alkyd
Polyvinylchloride
PVC
Polyethylene terephthalate
PET
Polyoxymethylene
POM
Zinc chloride
ZnCl2
Sodium iodide
NaI

16. Pilot Study: Pre-cleaning step

17. Pilot Study: Comparison between high density salt solution
Each type of plastic were spiked with ten pieces.
Density
Polypropylene (PP)
Polyethylene (PE)
Acrylic
Sodium chloride
1.2
Polyvinylchloride (PVC)
Polyethylene terephthalate (PET)
Zinc chloride
Sodium chloride
Zinc chloride PP 6 8 10 9 PE
Acrylic 2 7
PVC 4
PET 1

18. Methods Sediment collection from study sites.
Sieving through 1 mm and 35 um mesh.
Density separation (ZnCl2 , d = g/m3).
Visual examination under microscope.

19. Preliminary Results 1 mm Site: Avoca Street Retarding Basin
Predominant Land Use: Commercial

20. Preliminary Results 500 um Site: Cala Street Ponds
Predominant Land Use: Industrial

21. Preliminary Results Site: Albert Park Lake
Predominant Land Use: Open Space
1mm

22. Future work
To refine new technique to extract microplastics from freshwater sediment.
To categorize microplastics, for example colors and size from 20 wetlands.
To investigate the spatial distribution of microplastics in wetland sediment in relation to catchment land use.

23. Acknowledgement
I wish to thank Simon Sharp, Steve Marshall, Pat Bonney for assistance with this project
Thank you for Listening
Hsuan-Cheng Lu

24. Reference
Claessens, M., Van Cauwenberghe, L., Vandegehuchte, M.B., Janssen, C.R., New techniques for the detection of microplastics in sediments and field collected organisms. Mar Pollut Bull. 70, 227–233.
Hidalgo-Ruz, V., Gutow, L., Thompson, R.C., Thiel, M., Microplastics in the marine environment: a review of the methods used for identification and quantification. Environ. Sci. Technol. 46,