Occurrence of Attributes in Original Text
The text related to the cultural heritage 'Historic Centre of Siena' has mentioned 'Pollution' in the following places:
| Occurrence Sentence | Text Source |
|---|---|
| The Historic Centre of Siena is vulnerable to environmental pollution and intense tourist pressure, which strain city services during a few months of the year. | UNESCO |
| Concern for authenticity of buildings and monuments has been identified in the removal of architectural elements that are threatened by pollution and their replacement with replicas. | UNESCO |