Table 2.

Types of abiotic and biotic degradation of microplastics.

Degradation	Degradation Methods		Consequences of Degradation	Ref.
	Photodegradation	Visible, infrared, UV light Reaction through light and reactive species involvement with a catalyst	- Chain scission - Cross-linking - Flexibility loss, color change - Oxidative decomposition - Generation of reactive oxygen species - Complete mineralization to H2O, CO2	[25,26,27,28]
ABIOTIC	Thermal degradation	1. Identification of MPs by pyrolysis gas 2. High-temperature-production H, CO, CH4, or fuel oil 3. As a pretreatment technique for MP degradation at low temperatures	- Conformational changes - Depolymerization of fragments - Breakage of polymeric backbone, molecular deterioration, changes in tensile strength, alteration of crystallinity, reduction in durability, cracks and color changes	[29,30,31]
		Hydrolytic degradation (hydrogen ions in acidic or alkaline media)	- Chain breakage - Surface corrosion of polyesters - Cross-linking - Chain breakage - Chain breaking, formation of products - Mineralization of MPs	[31,32]
	Chemical degradation	Oxidative degradation (heat, light, atmospheric oxygen)
		Advanced oxidation processes
		Bacterial degradation	- Enzymatic oxidation - Hydrolysis - Chain scission	[33,34,35]
		Fungal degradation
BIOTIC	Biodegradation	Enzymatic biodegradation		[36]
		Combined biodegradation (by multiple bacteria)		[36]
		Algae degradation		[37]