In the sentence extracted from biomedical literature, identify all the chemical entities. The required answer format is the same sentence with HTML <span> tags to mark up specific entities. 
### Entity Markup Guides:
Use <span class="chemical"> to denote a chemical.

### Input Text: The absolute risk for bladder cancer in the cohort reached 10 % 16 years after diagnosis of Wegener ' s granulomatosis , and a history of bladder cancer was ( non - significantly ) twice as common as expected at the time of diagnosis of Wegener ' s granulomatosis .
### Output Text:
The absolute risk for bladder cancer in the cohort reached 10 % 16 years after diagnosis of Wegener ' s granulomatosis , and a history of bladder cancer was ( non - significantly ) twice as common as expected at the time of diagnosis of Wegener ' s granulomatosis . 