Table 3.

Positive/Neutral effects of CNMs in soil microorganism.

Reference	CNM	Organism	Treatment	Effect
Tong et al., 2007	Fullerene (C60)	Microbial communities	1 μg and 1000 μg C60 /g	No impact on the structure or function and enzymatic activities.
Nyberg et al., 2008	Fullerene (C60)	Microbial communities	Up to 50,000 mg/kg	No significant effects on microbial community activity.
Shrestha et al., 2013	MWCNT	Microbial communities	10–100 mg/kg	No observable effects on soil-microbial composition and enzymatic activities at lower concentrations.
			10,000 mg/kg	Decreased abundance in select bacterial species.
Wang et al., 2013	Graphene oxide	Anaerobic ammonium-oxidizing bacteria	0.1 g/L	Enhanced activity of anaerobic ammonium-oxidizing bacteria by 10%.
			0.05–0.1 mg/ml	Enhanced production of protein and carbohydrate.
Cordeiro et al., 2014	Fullerene (C60)	Gram-negative bacterial colonies	0.01, 0.10, and 1.00 mg/L	No changes in the growth of the colonies after 24 h exposure.