9276
This study was to investigate the neurotoxicity of multi - walled carbon nanotube ( MWCNT ) by measuring neuronal excitability in rat hippocampal neurons and exploring the underlying mechanism .
 Chemical: carbon
Please list all entity words in the text that fit the category.Output format is "type1: word1; type2: word2". 
Option: Chemical 
Text: {0} 
Answer:
 Chemical: carbon