6531
Our findings demonstrate that chronic arsenic exposure at levels that are commonly found in drinking water ( i . e . , 10 - 50 ppb ) alters cellular mechanisms critical to airway innate immunity .
 Chemical: arsenic
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: arsenic