Carbon based nanomaterial interactions with metals and metalloids in terrestrial environment: A review

The use of carbon based nanomaterials (CNMs) is diversifying and is being considered in so many sectors that their release into the environment is inevitable. Terrestrial ecosystems and particularly agrosystems are considered a major sink for CNMs due to their accumulation in sewage sludge widely used for crop production. These ecosystems already accumulated other contaminants such as metals and metalloids which are more closely monitored to date. Although reviews about these contaminants considered individually have already been published, no review focused on their interactions and the impact of these interactions on their respective transfer and impacts on dwelling organisms (bacteria, earthworms and plants). Indeed, CNMs and metal(loid)s can interact together as metal(loid)s are able to adsorb on the surface of CNMs under the influence of diverse parameters such as pH, organic matter content or intrinsic CNM properties, among others. In ecotoxicity studies, interactive mechanisms (synergy and antagonism) were most of the time highlighted even though the underlying mechanisms are not yet fully understood. This work questions the current paradigm in use for risk assessment related to the additivity of the risks in presence of a cocktail of contaminants and in fine on the strategies to be applied in order to guarantee food safety.

Automated summary

The use of carbon based nanomaterials (CNMs) in various sectors is increasing, leading to their inevitable release into the environment. Terrestrial ecosystems, especially agrosystems, are considered major sinks for CNMs due to their accumulation in sewage sludge used for crop production. This study raises questions about the current risk assessment paradigm regarding the additive effects of a cocktail of contaminants and explores strategies to ensure food safety.