Table 1.

Documented ecotoxicity of selected ENMs for environmental remediation.

Nanoparticles Type	Remediation Mechanism	Remediated Contaminants	Potential Toxicity	Test Organisms	Reference
nZVI	Adsorption; oxidation; reduction	metals; chlorinated pollutants	Algal growth inhibition; ROS generation; oxidative stress; disruption of membrane integrity; genotoxicity; morphological alterations of roots; oxygen consumption	bacteria; freshwater microalga; freshwater crustaceans; earthworm; plant	[48,49,74,75]
Iron-based ENMs	Adsorption; oxidation; reduction	metals; microbiological contaminants	Algal growth inhibition; ROS generation; oxidative stress; disruption of membrane integrity; genotoxicity; mutagenicity; reproduction impairment	bacteria; freshwater microalga; freshwater crustaceans; earthworm; plant; fish	[48,49,72]
TiO2	Photodegradation	organic contaminants	ROS generation; oxidative stress; membrane damage; cell viability reduction; reproduction impairment; tissues alterations and gill histopathology; neurotoxicity	bacteria; crustacean; plant; fish	[57,58,60,76]
ZnO	Photocatalysis; photodegradation; adsorption	organic contaminants; heavy metals	Algal growth inhibition; ROS generation; gill damage; embryotoxicity; metal stress via dissolution and ion release; membrane damages	bacteria; freshwater microalga; crustacean; fish	[58,60,61,77]
CNT-based ENMs	Catalytic facilitation; adsorption	organic contaminants; heavy metals	toxicity enhancement of contaminants; carrying of pollutants; ROS generation; growth rate inhibition; membrane damage	bacteria; microalga; crustaceans; mollusks	[58,69,70,78]