(a) General. Subpart B of this part and § 158.2201 describe how to use the table in paragraph (c) of this section to determine the environmental fate data requirements for antimicrobial pesticide products. Notes that apply to an individual test including specific conditions, qualifications, or exceptions are listed in paragraph (d) of this section.

(1) Environmental fate data are required to support the registrations of all end-use and manufacturing-use antimicrobial products.

(2) Data on transformation/degradation products or leachate residues of the parent compound are also required to support registration, if the transformation/degradation products or leachate residues meet one of the following criteria:

(i) More toxic, persistent, or bioaccumulative than the parent;

(ii) Have been shown to cause adverse effects in mammalian or aquatic reproductive studies; or

(iii) The moiety of concern (i.e., functional group in the parent chemical molecule that imparts adverse effects) remains intact.

(3) For the purpose of determining data requirements, the all other use patterns category includes the following use patterns:

(i) Agricultural premises and equipment.

(ii) Food-handling/storage establishments, premises, and equipment.

(iii) Commercial, institutional and industrial premises and equipment.

(iv) Residential and public access premises.

(v) Medical premises and equipment.

(vi) Human drinking water systems.

(vii) Materials preservatives.

(viii) Swimming pools.

(b) Key. MP = Manufacturing use product; EP = End-use product; R = Required; CR = Conditionally required; NR = Not required; TGAI = Technical grade of the active ingredient; TEP = Typical end-use product; PAIRA = Pure active ingredient radiolabeled; ROC = residue of concern.

(c) Antimicrobial environmental fate data requirements table. The following table shows the data requirements for environmental fate. The test notes appear in paragraph (d) of this section.

(d) Test notes. The following test notes apply to the data requirements in the table in paragraph (c) of this section:

1. For testing antifoulant paints and coatings, testing is to be performed separately with both sterile buffered distilled water and sterile synthetic seawater at pHs 5, 7, and 9.

2. Not required if:

i. The electronic absorption spectra, measured at pHs 5, 7 and 9, of the chemical and its hydrolytic products, if any, show no absorption or tailing between 290 and 800 nm, inclusive; or

ii. The results of the hydrolysis study at all three pHs (5, 7, and 9) demonstrates a half-life of less than 30 days.

3. The results of the activated sludge, respiration inhibition (ASRI) test determine which of the following tests are required: Ready biodegradability, porous pot, the biodegradation in activated sludge study as described in the “Simulation Tests to Assess the Biodegradability of Chemicals Discharged in Wastewater,” or simulation test—aerobic sewage treatment: A. activated sludge units.

i. If the ASRI test EC50 is equal to or less than 20 mg/L, then the applicant must choose either to:

A. Conduct the biodegradation in activated sludge study as described in the “Simulation Tests to Assess the Biodegradability of Chemicals Discharged in Wastewater”;

B. Conduct the porous pot test; or

C. Conduct the simulation test—aerobic sewage treatment: A. activated sludge units.

ii. If the ASRI test EC50 is greater than 20 mg/L, then the applicant must choose either to:

A. Conduct a ready biodegradability study; or

B. Conduct one of the following studies: The biodegradation in activated sludge study as described in the “Simulation Tests to Assess the Biodegradability of Chemicals Discharged in Wastewater,” the porous pot test, or the simulation test—aerobic sewage treatment: A. activated sludge units.

4. Pass criteria for the ready biodegradability study are: 70 percent removal of dissolved organic carbon (DOC) and 60 percent removal of theoretical oxygen demand (ThOD) or theoretical carbon dioxide (ThCO2) production for respirometric methods. These pass levels must be reached in a 10-day window within the 28-day period of the test. If the antimicrobial passes the ready biodegradability study, then no further testing is required. If the antimicrobial fails the ready biodegradability study, then the applicant must conduct one of the following studies: The biodegradation in activated sludge study as described in the “Simulation Tests to Assess the Biodegradability of Chemicals Discharged in Wastewater,” the porous pot test, or the simulation test—aerobic sewage treatment: A. activated sludge units.

5. For the all other use patterns category (as specified in § 158.2280(a)(3)), data are required based on a weight-of-evidence evaluation of the results of the hydrolysis, photodegradation in water, activated sludge sorption isotherm, biodegradability, and activated sludge, respiration inhibition tests.

6. Adsorption and desorption using a batch equilibrium method is preferred. In some cases, as when the antimicrobial pesticide degrades rapidly, soil column leaching with unaged or aged columns may be more appropriate to fully characterize the potential mobility of the parent compound and major transformation products.

7. For industrial processes and water systems, aquatic areas, and the all other use patterns category (as specified in § 158.2280(a)(3)), data are required based on a weight-of-evidence evaluation of the results of the hydrolysis, photodegradation in water, activated sludge sorption isotherm, biodegradability, and activated sludge, respiration inhibition tests.

8. The environmental media (soil, water, hydrosoil, and biota) to be utilized in these studies must be collected from areas representative of potential use sites.

9. For industrial processes and water systems, and aquatic areas, data are required for use sites that are intermittently dry.

10. Data are not required if the antimicrobial is an inorganic substance or a metal salt; or if the standardized soil profiles demonstrate that the antimicrobial is likely to readily degrade either microbially or via redox reactions (chemically) and no transformation/degradate/leachate products of concern (as described under § 158.2280(a)(2)) are produced.

11. Analytical methods used to generate data associated with this study must include results of a successful confirmatory method trial by an independent laboratory.

12. Protocols must be approved by the Agency prior to the initiation of the study.

13. For industrial processes and water systems, wood preservatives, and the all other use patterns category (as specified in § 158.2280(a)(3)), data are required based on the potential for aquatic exposure and if the weight-of-evidence indicates that the active ingredient or principal transformation products are likely to have the potential for persistence, mobility, nontarget aquatic toxicity, or bioaccumulation.

14. Data are required if the weight-of-evidence indicates that the active ingredient or principal transformation products are likely to occur in nontarget freshwater, estuarine, or marine waters such that human or environmental exposures are likely to occur. In making that determination, the Agency takes into account other factors such as the toxicity of the chemical(s), available monitoring data and the vulnerability of the freshwater, estuarine, or marine water resources in the antimicrobial use area.

15. For wood preservatives, an aquatic leaching study is required. A soil leaching study is required if human or environmental exposures are likely to occur from leachates that contain the active ingredient or principal transformation products from wood treated with a preservative product. Protocols must be approved by the Agency prior to the initiation of the study.

16. For antifoulant paints and coatings, a leaching study is required. Protocols must be approved by the Agency prior to the initiation of the study.

17. Protocols, which include the residues of concern (such as parent, degradate/transformation product, and/or leachate residues) that would be monitored, must be approved by the Agency prior to the initiation of the study.

18. A biodegradation study is not required if the antimicrobial meets one or more of the following criteria:

i. Classified as a metal,

ii. Relatively volatile, but not hydrophobic,

iii. Highly reactive,

iv. Both the parent and all transformation/degradate products (as described under § 158.2280(a)(2)) have half-lives of less than 3 hours,

v. None of the registered or proposed product uses would result in transport of the parent and its transformation/degradate products (as described under § 158.2280(a)(2)) to a wastewater treatment plant.

19. The activated sludge sorption isotherm test is not required if the antimicrobial is:

i. Relatively volatile, but not hydrophobic;

ii. Highly reactive; or

iii. The log Kow is less than 3.0.

20. If the criteria of test note 19 of this paragraph are not met, then the activated sludge sorption isotherm test is required if one or more of the following criteria are also met:

i. The antimicrobial is a metal,

ii. The log Kow is greater than or equal to 3.0,

iii. The antimicrobial is positively charged or polycationic,

iv. The EC50 in the activated sludge, respiration inhibition test is less than or equal to 20 mg/L,

v. The EC50 in the activated sludge, respiration inhibition test is greater than 20 mg/L, and the antimicrobial fails the ready biodegradability study.

21. The activated sludge respiration inhibition study is not required if none of the registered or proposed product uses would result in transport of the parent and its transformation/degradate products (as described under § 158.2280(a)(2)) to a wastewater treatment plant.