Document ID: chunk:federal_register_of_legislation:F2013C00288:reg:4:p2
Version: federal_register_of_legislation:F2013C00288
Segment Type: reg
Provision Reference: reg 4 (pt 2/5)
Character Range: 1579130–1582908

by Heemsbergen et al. (2008) to use the BurrliOZ SSD method (Campbell et al. 2000).
Table 29. Geometric mean values of arsenic (As) toxicity data (expressed in terms of total As) for soil invertebrate species, terrestrial bird and mammal species and plant species.
Test species            Geometric mean (mg/kg)
Common name             Scientific name         EC10 or NOEC  EC30 or LOEC  EC50
Bean                    Phaseolus vulgaris      22.6          84            168
Blueberry               Vaccinium sp.           22.2          55            111
Common rat              Rattus norvegicus       10.0          25            50
Corn                    Z. mays                 25.1          67            123
Cotton                  Gossypium sp.           20.8          52            104
Deer mouse              Peromyscus maniculatus  320           1600          1600
Earthworm               Eisenia fetida          20.0          100           100
Earthworm               L. rubellus             76.1          381           381
Earthworm               L. terrestris           100           250           500
Fulvous whistling duck  Dendrocygna bicolour    229           1145          1145
Grass                                           13.4          81            161
Northern bobwhite       Colinus virginianus     54.0          270           270
Oat                     A. sativa               22.7          44            70
Pea                     Pisum sativum           20.8          52            104
Pine                                            292           731           1462
Potato                  Solanum tuberosum       36.3          108           181
Radish                  Raphanus sativa         67.7          169           339
Sheep                   Ovis aries              25.0          63            125
Soyabean                Glycine max             9.7           24            35
Tomato                  L. esculentum           62.5          166           263
Wheat                   T. aestivum             43.4          153           307

In order to maximise the use of the available toxicity data, conversion factors (adopted from the Australian and New Zealand guidelines for fresh and marine water quality (ANZECC & ARMCANZ 2000) by Heemsbergen et al. (2008)) were used to permit the inter-conversion of NOEC, LOEC, EC50, EC30 and EC10 data. Conversion factors for cations (for example, Cu and Zn) were developed by the NBRP and recommended by Heemsbergen et al. (2008) in preference to the default conversion factors adopted from the WQGs. However, as As is predominantly found in anionic form in soils, the default conversion factors were used (Table 30).

Table 30. The default conversion factors used to convert different measures of toxicity to chronic no observed effect concentrations (NOECs) or 10% effect concentrations (EC10). Sourced from Heemsbergen et al. (2008), who adopted the values from the Australian and New Zealand guidelines for fresh and marine water quality (ANZECC & ARMCANZ 2000).
Toxicity dataa                Conversion factor
EC50 to NOEC or EC10          5
LOEC or EC30 to NOEC or EC10  2.5
MATC* to NOEC or EC10         2

  a EC50 is the concentration that causes a 50% effect, EC30 is the concentration that causes a 30% effect, EC10 is the concentration that causes a 10% effect, NOEC = no observed effect concentration, LOEC = lowest observed effect concentration, *MATC = the maximum acceptable toxicant concentration and is the geometric mean of the NOEC and LOEC.

4.4              Normalisation relationships
It is well known that soil physicochemical properties affect the toxicity and bioavailabiity of As. However, this knowledge is qualitative. For example, Sheppard (1992) reviewed the existing