1 Microplastics as Emerging Pollutants in Urban Waterways 1 1.1 Background 4 1.2 MPs as environmental pollutants 5 1.3 Pollution of urban waterways by MPs 5 1.3.1 Occurrence 5 1.3.2 Morphological characteristics 8 1.

4 Comparison of MPs presence in the water column and the sediment bed 9 1.5 Limitations in MPs quantification 10 1.6 Summary 11 References 13 2 Factors Influencing MPs Presence in Urban Waterways 15 2.1 Background 18 2.2 Influence of emission sources 19 2.2.1 Terrestrial-based sources 19 2.2.

2 Aquatic-based sources 20 2.2.3 Atmospheric-based sources 21 2.3 Influence of environmental factors 23 2.3.1 Hydrodynamic conditions 23 2.3.2 Photothermal degradation 25 2.

3.3 Microorganism colonisation 26 2.4 Summary 26 References 28 3 Risk Associated with MPs in Urban Waterways 30 3.1 Background 33 3.2 Release of toxic additives in MPs 34 3.2.1 Organic compounds 34 3.2.

2 Metals 36 3.3 Interaction with contaminants existing in the environment 39 3.3.1 Chemical contaminants 39 3.3.2 Microorganisms 40 3.4 Summary 41 References 42 4 Case Study--Risks Posed by MPs Presence and Transport in Brisbane River Sediments, Australia 44 4.1 Background 47 4.

2 Sampling design 47 4.2.1 Study sites selection 47 4.2.2 Sample collection 58 4.3 Laboratory data generation 60 4.3.1 MPs separation, identification and quantification 61 4.

3.2 Nutrient analysis 65 4.3.3 Metals analysis 65 4.4 Risks associated with MPs 66 4.4.1 Abundance of MPs in Brisbane River sediments 66 4.4.

2 Hazard index assessment of different MP types 71 4.4.3 Risks from nutrients and metals in Brisbane River sediments 72 4.5 Risks associated with MPs transport and dispersion 73 4.5.1 Modelling approach 73 4.5.2 MP dispersal and transport model development 75 4.

5.3 Variability of MPs migration behaviour in Brisbane River sediments 77 4.6 Summary 82 References 83 5 Practical Implications and Recommendations for Further Research 86 5.1 Implication of Plastic Pollutants in Urban Waterways 89 5.1.1 Tracking Plastic Pollutants 89 5.1.2 Implementation of Waste Plastics Management 89 5.

2 Recommendations for Further Research 91.