Document ID: chunk:federal_register_of_legislation:F2013C00288:reg:9:p2
Version: federal_register_of_legislation:F2013C00288
Segment Type: reg
Provision Reference: reg 9 (pt 2/3)
Character Range: 1710665–1715047

144
Lettuce             L. sativa                 52.6          125           154
Maize               Z. mays                   49.4          94.8          127
Oats                A. sativa                 55.3          83.9          122
Onion               Allium cepa               37.6          59.7          84.5
Perennial ryegrass  L. perenne                40.9          50.2          57.1
Radish              R. sativus                57.5          65.5          66.8
Spinach             Spinacia oleracea         26.9          41.1          47.2
Tomato              L. esculentum             94.8          142           238

Table 71. The lowest geometric mean values of the normalised nickel (Ni) toxicity data for soil microbial processes.
Microbial process                         Geometric means (mg/kg)
NOEC or EC10                              LOEC or EC30             EC50
Arylsulfatase                             784                      1176  1191
Aspergillus clavatus (hyphal growth)      14.9                     45.9  91.0
Aspergillus flavus (hyphal growth)        451                      586   689
Aspergillus flavipes (hyphal growth)      398                      444   475
Aspergillus niger (hyphal growth)         459                      545   606
ATP content                               75.5                     113   392
Gliocladium sp. (hyphal growth)           230                      560   1036
Bacillus cereus (colony count)            327                      1010  1958
Dehydrogenase                             6.8                      20.8  85.5
Glucose respiration                       79.5                     119   238
Glutamate respiration                     44.5                     191   381
Maize residue respiration                 134                      201   402
Nitrification                             81.3                     122   244
N-mineralisation                          95.8                     144   287
Nocardia rhodochrous (colony count)       203                      662   943
Penicillium vermiculatum (hyphal growth)  117                      271   460
Phosphatase                               524                      1347  5715
Protease                                  75.5                     113   392
Proteus vulgaris (colony count)           17.2                     88.8  249
Respiration (CO2 release)                 102                      2583  4593
Rhizopus stolonifer (hyphal growth)       331                      404   459
Rhodotorula rubra (colony count)          283                      837   1796
Sacharase                                 75.5                     113   392
Serratia marcescens (colony count)        178                      337   395
Trichoderma viride (hyphal growth)        608                      686   740
Urease                                    222                      332   879

9.4              Normalisation relationships
Normalisation relationships relating the toxicity of Ni to three soil microbial processes (nitrification, glucose-induced respiration and maize residue mineralisation) were developed by Oorts et al. (2006b). Two normalisation relationships have also been developed for crops (tomato and barley) by Rooney et al. (2007). In addition, the EU Ni ecological risk assessment (EC 2008b) reported Ni normalisation relationships for two soil invertebrates (F. candida and E. fetida). All of these relationships were developed for both fresh and aged contamination and are presented in Table 72. No Ni normalisation relationships have been developed for Australian species and/or soils.

The normalisation relationships presented in Table 72 all model EC50 toxicity data, with the exception of the maize residue mineralisation which models EC20 data. Relationships between the logarithm of Ni NOEC and EC10 data and logarithm of CEC were developed as part of this project. Normalisation relationships were developed for (a) all organisms, (b) each group of organisms separately, and (c) each species or microbial process separately. Only CEC was used to develop the normalisation relationships as in all the published relationships for Ni the CEC was the best parameter (Oorts et al. 2006b; Rooney et al. 2007; EC 2008b). Only six normalisation relationships could explain more than 50% of the variation in the toxicity data (i.e. r2 > 0.5) and