. 2020 Jul 27;10(8):1469. doi: 10.3390/nano10081469

Table 5.

TiO₂ NPs effects terrestrial and aquatic organisms.

Experimental Conditions	Organisms	Impacts of TiO₂	Ref.
Terrestrial Organisms
TiO₂ NPs Size: 25 nm Treatments: 500 and 5000 mg kg⁻¹ Period: up to 48 days	Nematodes (C. elegans)	Increased generation of intracellular reactive oxygen species. Toxicity reduced and the lifespan of survived nematodes increased in response to TiO₂ NPs exposure.	[129]
TiO₂ NPs Treatments: 0, 5, 50, and 500 mg kg⁻¹ Period: 120 days	Earthworm (Eisenia fetida)	Lower glutathione/oxidized glutathione (GSH/GSSG) ratio and significant decrease in superoxide dismutase (SOD) activity was observed for 500 mg/kg TiO₂ concentration.	[130]
TiO₂ NPs Size: 50–100 nm Treatments: 0, 150 or 300 mg kg⁻¹ of dry soil Period: 15, 30, 60 and 90 days	Bacterial community and Eisenia fetida	Unamended and earthworm—amended soil increased certain available bacterial groups such as Firmicutes and Acetobacter whereas decreased Verrucomicrobia and Pedobacter abundance.	[131]
TiO₂ NPs (anatase) Treatments: 10, 50, and 100 nm Period: 2–3 months	Mice	Intestinal inflammation with lower body weight. Mice with removed gut microbiota did not show this phenomenon.	[132]
TiO₂ NPs Size: 23 ± 6.8 nm Treatments: 0.5, 2.5, and 10 mg kg⁻¹ Period: 2 h and 35 days	Sprague–Dawley rats	Persistent inflammation of lung and liver genotoxicity.	[133]
Aquatic Organisms
TiO₂ NPs Treatments: 0.25, 0.5, and 1.0 mg L⁻¹ Period: 21 days	Daphnia magna	TiO₂ with 20% rutile and 80% anatase had a highest mortality rate as compared to other crystalline forms.	[134]
Biosynthesized TiO₂ NPs Size: 43–56 nm Treatments: 0, 2.5, 5, 10, 20, and 40 mg L⁻¹	Zebrafish (Danio rerio)	Significant malformations such as tail curvature, egg coagulation, bend the spine and delayed hatching was observed at a concentration of 2.5 mg L⁻¹ during 8 to 120 h post fertilized period.	[135]
TiO₂ NPs Treatments: 25, 125, and 250/mg L⁻¹ Period: 28/days	Red swamp crayfish (Procambarus clarkia)	The mortality rate was observed to be 0, 3.3, and 10% in response to 25, 125, and 250/mg L⁻¹ of TiO₂ NPs, respectively.	[136]
TiO₂ NPs Treatments: 1.0 and 5.0 mg L⁻¹ Period: 4 and 14 days	Nile tilapia (Oreochromis niloticus)	Acute exposure caused oxidative stress with a decrease in catalase (60%), superoxide dismutase (27%), and glutathione peroxidase (37%), while 14 days of exposure elevated the catalase (61%), glutathione-S-transferase (54%), glutathione peroxidase (32%), and glutathione reductase (93%).	[137]
TiO₂ NPs Treatments: 500, 1000, 1500, and 2000 mg L⁻¹ Period: 24 h	Brine shrimp (Artemia salina)	Mortality rate of 5, 20, 20, 53, and 57% was observed in response to 0, 500, 1000, 1500, and 2000 mg L⁻¹ TiO₂ NPs, respectively.	[138]