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: Estrogen - replacement therapy appeared to have no effect on either the efficacy or safety profile of lovastatin .
### Output Text:
Estrogen - replacement therapy appeared to have no effect on either the efficacy or safety profile of <span class="chemical">lovastatin</span> . 