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| pollutant level A value representing the concentration of a polluting agent in a specified area, often determined by a measuring and recording device (在一个特定的区域代表污染浓度的一个值，通常由测量和记录设备决定。) | |||
| contaminant level | |||
| 污染 物 水平: 14 phrases in 3 subjects |
| Earth sciences | 3 |
| Technology | 7 |
| Water resources | 4 |