Toxicity Assessment of Urban Dust from Barranquilla, a Colombian Caribbean City, using Caenorhabditis elegans

Abstract

Urban dust is a reservoir of potentially toxic elements (PTEs) that can be incorporated into aquatic ecosystems where they bioaccumulate and biomagnify causing toxic effects. The aim of this work was to assess the PTEs’ concentrations and toxicity to Caenorhabditis elegans of inorganic extracts from urban dust of Barranquilla, the largest Colombian Caribbean city. Trace elements were analyzed by inductively couple plasma-mass spectrometry. PTEs concentration decreased in the order Sr > Cu > Ba > Mo > Se > Cr > V > Ni > As > Zn > Mn > Sb > Co > Sn > Cd > La > Ce >Tl ≈ Bi > Ag ≈ Pb. Inorganic extracts from urban dust affected physiological parameters in the nematode, such as survival, growth and locomotion. Lethality showed a positive relation with Sr and negative with V. Growth displayed a negative association with Mo. Expression of mtl-2, sod-4, and unc-25 genes was induced by PTEs. The results suggest that C. elegans is a sensitive organism capable of responding to exposure to urban dust extracts, being a suitable sensor for the implementation of warning systems related to risks to biota associated with air pollution.