Effects at molecular level of multi-walled carbon nanotubes (MWCNT) in Chironomus riparius (DIPTERA) aquatic larvae

Highlights: • The present of MWCNT in the digestive tract was clearly visible in exposed larvae. • This work shows the capability of MWCNT to alter the expression of genes involved in DNA repairing mechanisms (ATM). • MWCNT to alter the expression of genes which are involved in cell stress response (hsp27 and hsp70) and cell apoptosis. -- Abstract: Nowadays, due to the physical, chemical, electrical, thermal and mechanical properties of carbon nanotubes (CNT), its have been currently incorporated into biomedical products and they are employed in drug delivery drug administration, biosensor design, microbial treatments, consumer products, and new products containing CNT are expected in the future. CNT are hydrophobic and have a tendency to accumulate in sediments if they are released into aquatic ecosystems. Vertebrate studies have revealed concerns about the toxicity of carbon nanotubes, but there is very limited data on the toxic effects in aquatic invertebrate species. The aim of the present study is to determine the effects of MWCNT in Chironomus riparius at the molecular level, understanding its mode of action and analyzing the suitability of this species to monitor and assess risk of nanomaterials in aquatic ecosystems. To evaluate possible toxic effects caused by carbon nanotube environmental dispersion with regard to aquatic compartment, we study the mRNA levels of several related genes with DNA repairing mechanisms, cell stress response, cell apoptosis and cytoskeleton by Real-Time PCR and proposed a freshwater invertebrate C. riparius, which is a reference organism in aquatic toxicology. The obtained results show a transcriptional alteration of some genes included in this study, indicating that different cell processes are affected and providing one the first evidences in the mechanisms of action of MWCNT in invertebrates. Moreover, this data reinforces the need for further studies to assess the environmental risk of nanomaterial to prevent future damage to aquatic ecosystems.