| # | Concept | Culture | Statement | Freq. |
|---|---|---|---|---|
| 1 | acid rain | United States | Acid rain is a well-known environmental issue caused by industrial pollution and is a concern for ecosystems and infrastructure. | 1 |
| 2 | acid rain | United States | Caused by emissions from industrial and vehicular sources, leading to environmental damage and ecosystem harm | 1 |
| 3 | acid rain | United States | Considered a serious environmental issue with negative impacts on ecosystems and infrastructure | 1 |