Question: why cant you swim in the east river nyc
[{'answer': 'heavy pollution', 'provenance': [{'wikipedia_id': '9592', 'title': 'East River', 'start_paragraph_id': 57, 'start_character': 7, 'end_paragraph_id': 57, 'end_character': 22, 'bleu_score': 1.0, 'section': 'Section::::Ecosystem collapse, pollution and health.\n'}]}, {'provenance': [{'wikipedia_id': '9592', 'title': 'East River', 'start_paragraph_id': 57, 'start_character': 0, 'end_paragraph_id': 57, 'end_character': 668, 'bleu_score': 0.9476591708034281, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 13451803792339428256}, 'section': 'Section::::Ecosystem collapse, pollution and health.\n'}]}]