WAC 173-333-320   What criteria will ecology use to identify and add chemicals or chemical groups to the PBT list?  (1) Purpose. This section describes the criteria that ecology will use to determine whether a chemical or group of chemicals should be included on the PBT list.

     (2) Criteria for identifying PBTs. A chemical or group of chemicals will be included on the PBT list if ecology determines it meets each of the following criteria:

     (a) Persistence. The chemical or chemical group can persist in the environment based on credible scientific information that:

     (i) The half-life of the chemical in water is greater than or equal to sixty days; or

     (ii) The half-life of the chemical in soil is greater than or equal to sixty days; or

     (iii) The half-life of the chemical in sediments is greater than or equal to sixty days; and

     (b) Bioaccumulation. The chemical or chemical group has a high potential to bioaccumulate based on credible scientific information that the bioconcentration factor or bioaccumulation factor in aquatic species for the chemical is greater than 1,000 or, in the absence of such data, that the log-octanol water partition coefficient (log K_ow) is greater than five; and

     (c) Toxicity. The chemical or chemical group has the potential to be toxic to humans or plants and wildlife based on credible scientific information that:

     (i) The chemical (or chemical group) is a carcinogen, a developmental or reproductive toxicant or a neurotoxicant;

     (ii) The chemical (or chemical group) has a reference dose or equivalent toxicity measure that is less than 0.003 mg/kg/day; or

     (iii) The chemical (or chemical group) has a chronic no observed effect concentration (NOEC) or equivalent toxicity measure that is less than 0.1 mg/L or an acute no observed effect concentration (NOEC) or equivalent toxicity measure that is less than 1.0 mg/L.

     (d) Additional criteria applicable to metals. The chemical or chemical group is a metal and ecology determines that it is likely to be present in forms that are bioavailable.

     (3) Degradation products. Ecology will consider both the parent chemical and its degradation products when making decisions on whether a chemical meets the criteria in subsection (2) of this section. If a parent chemical does not meet the criteria in this section but degrades into chemicals that do meet the criteria in subsection (2) of this section, the parent chemical may be considered for inclusion on the PBT list and in the development of a CAP. Alternately, ecology may decide not to include the parent chemical on the PBT list, but consider it during the development of a CAP for derivative chemicals.



[Statutory Authority: 2004 c 276 and chapter 70.105 RCW. 06-03-094 (Order 04-07), § 173-333-320, filed 1/13/06, effective 2/13/06.]