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Table 2 Data set characteristics of the selected data sets

From: Chemical surveillance in freshwaters: small sample sizes underestimate true pollutant loads and fail to detect environmental quality standard exceedances

Data setMean annual loadSDRangeSkewnessDeviation from normality (p value)
Benzo(a)pyrene4.58a3.73a22.0a2.704.55 × 10−8
4-tert-Octylphenol233a68.0a314a− 0.020.89
Fluoranthene13.1a16.0a94.0a3.413.33 × 10−11
Fluoranthene, manipulated data set8.71a4.02a20.0a0.721.17 × 10−3
DEHP 20071.51b0.79b4.69b1.971.02 × 10−5
DEHP 20081.18b0.64b2.48b0.962.71 × 10−4
DEHP 20100.68b0.40b2.04b1.352.9 × 10−4
DEHP 20160.58b0.25b1.16b0.320.43
  1. All calculated values are based on the concentrations of 52 weekly composite samples. Variability is expressed as SD (standard deviation) and range. Normality was checked by the Shapiro–Wilk test (α = 0.05)
  2. ang/L
  3. bµg/L