Fine Particulate Matter-induced Toxic Effects in an Animal Model of Caenorhabditis elegans

Research has been focused on the health hazards of ambient PM_(2.5) related to humans. Many PM_(2.5) toxicity assessments using in vitro studies have focused on PM_(2.5)-bounded hazardous pollutants. However, PM_(2.5) toxicity assessment by in vivo studies allow for better observation of the overall effects of PM_(2.5) exposure on entire organisms, making in vivo PM_(2.5) toxicity assessment relevant. The toxic effects of outdoor PM_(2.5), collected from National Pingtung University of Science and Technology (NPUST) and Linluo Junior High School (LJHS), Pingtung, Taiwan, on nematode Caenorhabditis elegans (C. elegans) were investigated. PM_(2.5) from NPUST and LJHS were found to be 4.5 and 2.5 μg Nm^(-3), respectively, which did not meet the standard. This levels of PM_(2.5) in Taiwan. For acute toxicity, no significant PM_(2.5) lethality on C. elegans was observed between NPUST and LJHS. PM_(2.5) from NPUST exhibited greater toxicity to lifespan (ageing), locomotion (head thrash), and reproduction (brood size) in the C. elegans animal models than that from LJHS; therefore, adverse effects could be correlated with PM_(2.5) concentrations. Prolonged exposure to PM_(2.5) led to more severe toxicity in nematodes as compared to acute exposure. In conclusion, this study suggests that the long-term adverse effects of ambient PM_(2.5) on environmental organisms should be carefully considered even when PM_(2.5) is at low levels. C. elegans is a sensitive animal model for the evaluation of PM_(2.5) ecotoxicity.