Table 1 Split-point values assigned to uncertainty categories I–IV for ECs in the Yangtze River sediment
From: Priority screening on emerging contaminants in sediments of the Yangtze River, China
Uncertainty category | Description | Proportion of chemicals detected in all sample sites | Ecological risks |
|---|---|---|---|
I | Plenty monitoring data and hazard assessment utilizing experimental toxicity |  ≥ 4 provinces and ≥ 50 sites | Both effects utilizing experimental data |
II | Sufficient monitoring data but hazard assessment utilizing predicted toxicity |  ≥ 4 provinces and ≥ 50 sites | One or two effects utilizing predicted data |
III | Ecological risk assessment utilizing experimental toxicity but few monitoring data |  < 4 provinces and ≥ 50 sites | Ecotoxicity effect utilizing experimental data |
IV | Few monitoring data and hazard assessment utilizing predicted toxicity |  < 4 provinces and ≥ 50 sites | Ecotoxicity effect utilizing predicted values |