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Environmental and Workplace Health

Priority Substances List Assessment Report for Non-pesticidal organotin compounds

Table 2 Comparisons Between Estimated Effects Thresholds for Environmental Biota and Environmental Concentrations of Non-pesticidal Organotin Compounds

Organotin Compound

Endpoint for Most Sensitive Environmental Organism

Factors Applied

Estimated Effects Threshold (EET)

Environmental Concentrations (EC)

EET/EC

Monomethyltin (Freshwater)

48-hour LC50 for Daphnia magna 460 µg Sn/L   (Steinhauser et al., 1985)

20a x 2c

11.5 µg Sn/L

0.324 µg Sn/L (mean across Canada were detected; detection frequency = 12%

35

Monomethyltin (Marine)

72-hour EC50 for growth in the diatom Skeletonema costatum 40 µg Sn/L (Walsh et al., 1985)

20a x 2c

1.0 µg Sn/L

0.1 µg Sn/L (mean in seawater where detected; detection frequency = 3%

10

Dimethyltin (Freshwater)

48-hour LC50 for Daphnia magna 30 µg Sn/L (Steinhauser et al., 1985)

20a

1.5 µg Sn/L

0.092 µg Sn/L (mean across Canada where detected; detection frequency = 10%

16

Dimethyltin (Marine)

72-hour EC50 for growth in the diatom Skeletonema costatum   > 270 µg Sn/L (Walsh et al, 1985)

20a

> 13.5 µg Sn/L

<0.01 µg Sn/L (no detection observed in seawater, n = 70; detection limit = 0.01 µg Sn/L)

> 1350

Monobutyltin (Freshwater)

48-hour LC50 for the red killifish, Oryzias latipes 16 000 µg Sn/L (Nagase et al., 1991)

20a x 4c

200 µg Sn/L

0.216 µg Sn/L (mean across Canada were detected; detection frequency = 24%)

926

Monobutyltin (Marine)

48-hour IC50 for growth inhibition in selected marine yeasts   2100 µg Sn/L (Cooney et al., 1989)

20a x 10c

10.5 µg Sn/L

0.018 µg Sn/L (mean in seawater where detected; detection frequency = 19%

583

Dibutyltin (Freshwater)

110 d LOEL for mortality in rainbow trout, Oncorhynchus mykiss 95 µg Sn/L (de Vries et al., 1991)

10b

9.5 µg Sn/L

0.148 µg Sn/L (mean across Canada where detected; detection frequency = 24%

64

Dibutyltin (Marine)

72-hour EC50 for growth in the diatom Skeletonema costatum 10 µg Sn/L (Walsh et al., 1985)

20a

0.5 µg Sn/L

0.098 µg Sn/L (mean in seawater where detected; detection frequency = 29%

5

Mono-octyltin (Freshwater)

No toxicity data available

N/A

N/A

<0.01 µg Sn/L (no detections observed across Canada, n = 274; detection limit = 0.01 µg Sn/L)

N/A

Mono-octyltin (Marine)

No toxicity data available

N/A

N/A

<0.01 µg Sn/L (no detections observed in seawater, n = 70; detection limit = 0.01 µg Sn/L)

N/A

Dioctyltin (Freshwater)

48-hour LC50 for Daphnia magna 1.0 µg Sn/L (Steinhauser et al., 1985)

20a x 10c

0.005 µg Sn/L

<0.01 µg Sn/L (no detections observed across Canada, n = 274; detection limit = 0.01 µg Sn/L)

>0.5

Dioctyltin (Marine)

No toxicity data available

N/A

N/A

<0.01 µg Sn/L (no detections observed in seawater, n = 70; detection limit = 0.01 µg Sn/L)

N/A

  1. to convert from acute LC50, IC50, or EC50 to chronic NOEL and to account for the extrapolation of lab results to the field and differences in species sensitivity
  2. to convert from chronic Lowest-Observed-Effect-Level (LOEL) to a NOEL and to account for difference between laboratory and field conditions and species sensitivity
  3. to compensate for limited toxicity data or use of non-standard toxicity tests