Document ID: chunk:federal_register_of_legislation:F2013C00288:reg:6:p5
Version: federal_register_of_legislation:F2013C00288
Segment Type: reg
Provision Reference: reg 6 (pt 5/5)
Character Range: 1622810–1626090

a well-known metabolite of DDT and is relatively well studied. However, there is considerably less information available on the environmental fate, metabolism, degradation and toxicity of these metabolites than on DDT. The HILs and some soil quality guidelines use a sum of DDT, DDE and DDD concentration as an SQG , for example,  the Dutch and Flemish SQGs. An SQG could be derived for the sum of DDT, DDE and DDD by assuming the compounds have concentration-additive toxicity.
Table 45. Major metabolites of DDT (Sourced from WHO 1989).
Abbreviation of metabolite  Chemical name of metabolite
DDE                         1,1'-(2,2-dichloroethenylidene)-bis[4-chlorobenzene]
TDE(DD)                     1,1'-(2,2-dichloroethylidene)-bis[4-chlorobenzene]
DDMU                        1,1'-(2-chloroethenyldene)-bis[4-chlorobenzene]
DDMS                        1,1'-(2-chloroethylidene)-bis[4-chlorobenzene]
DDNU                        1,1'-bis(4-chlorophenyl)ethlyene
DDOH                        2,2-bis(4-chlorophenyl)ethanol
DDA                         2,2-bis(4-chlorophenyl)-acetic acid
Methoxychlor                1,1'-(2,2,2-trichloroethylidene)-bis[4-methoxybenzene]
Perthane                    1,1'-(2,2-dichloroethylidene)-bis[4-ethylbenzene]
DFDT                        1,1'-(2,2,2-trichloroethylidene)-bis[4-fluorobenzene]

6.10          Comparison with other guidelines
Soil quality guidelines for DDT in a number of jurisdictions are presented in Table 46. These SQGs have a variety of purposes and levels of protection and therefore a comparison of the values is problematic. The SQGs for DDT range from 0.01 to 4 mg/kg total DDT, both from the Netherlands. The original NEPM  (NEPC 1999) did not include an EIL for DDT. However, there are four HIL values of 260, 700, 400 and 4,000 mg/kg for land use settings A, B, C and D[3] for the sum of DDT, DDD, and DDE (Schedule B1). The SQGs for urban residential/public open space soil contaminated with fresh DDT based on NOEC & EC10, LOEC & EC30, and EC50 data were 70, 170 and 350 mg/kg. These values are considerably higher than the SQGs from other jurisdictions and this reflects the different methods that are used to account for biomagnification. The SQG(NOEC and EC10) and SQG(LOEC & EC30) are approximately 27% and 67% respectively, of the HIL for the standard residential setting ( setting A) which assumes direct exposure and the consumption of some food grown on the contaminated soil. The SQGs should still offer a considerable degree of protection.
Table 46. Soil quality guidelines for DDT in a number of jurisdictions.
Name of the DDT soil quality guideline      Value of the guideline
                                            (mg/kg as total)
Dutch target values1                        0.01
Dutch intervention value1                   4
Canadian SQG (residential)2                 0.7
Eco-SSL plants3                             NA
Eco-SSL soil invertebrates3                 NA
Eco-SSL avian3                              0.093
Eco-SSL mammalian3                          0.021
EU potentially unacceptable (residential)4  14

1 = VROM 2000
2 = CCME 1999d, 2006 and http://www.ccme.ca/publications/list_publications.html#link2
3 = http://www.epa.gov/ecotox/ecossl/
4 = Carlon 2007
NA = not available