Toxicity comparison between pristine and sulfonate modified nanopolystyrene particles in affecting locomotion...

Sulfonate modified polystyrene is potentially used in medical application; however, the effect of sulfonate modification on polystyrene toxicity is still largely unclear. We here compared the neurotoxicity between pristine and sulfonate modified nanopolystyrene particles in nematode Caenorhabditis elegans. Exposure to nanopolystyrene (35 nm) caused neurotoxicity on locomotion behaviors (head thrash, body bend, forward movement, and backward movement) and sensory perception behaviors (chemotaxis to NaCl or diacetyl). Exposure to nanopolystyrene also induced the damage on development of dopaminergic neurons as reflected by relative fluorescence intensity, number of discontinuous dendrite, and number of abnormal cell body. Moreover, we found that sulfonate modification effectively enhanced the neurontoxicity of nanopolystyrene on locomotion behaviors, sensory perception behaviors, and development of dopaminergic neurons. Our results highlight the possibility of sulfonate modification in increasing neurotoxicity of nanopolystyrene exposure on environmental organisms.