18725
In contrast , GaAs exposure is associated with microcytic haemolytic anaemia thereby aggravating any possible oxygen undersupply .
 Chemical: GaAs; Chemical: oxygen
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: GaAs; Chemical: oxygen