(a) Identification of testing substance.

(1) 1,2,3- and 1,2,4-trichlorobenzenes, CAS Numbers 87-61-6 and 120-82-1 respectively, shall be tested in accordance with this section.

(2) The substances identified in paragraph (a)(1) of this section shall be 99 percent pure and shall be used as the test substances in each of the tests specified.

(3) For health effects testing required under paragraph (e) of this section, the test substance shall not contain more than 0.05 percent benzene and 0.05 percent hexachlorobenzene.

(b) Persons required to submit study plans, conduct tests, and submit data.

(1) All persons who manufacture or process substances identified in paragraph (a)(1) of this section, other than an impurity, from May 21, 1986, to the end of the reimbursement period, shall submit a letter of intent to test or exemption applications and shall conduct tests, in accordance with part 792 of this chapter, and submit data as specified in this section, subpart A of this part and part 790 of this chapter for two-phase rulemaking.

(2) Persons subject to this section are not subject to the requirements of §790.50(a) (2), (5), (6) and (b) and §790.87(a)(1)(ii) of this chapter.

(3) Persons who notify EPA of their intent to conduct tests in compliance with the requirements of this section must submit plans for those tests no later than 30 days before the initiation of each of those tests.

(4) In addition to the requirements of §790.87(a)(2) and (3) of this chapter, EPA will conditionally approve exemption applications for this rule if EPA has received a letter of intent to conduct the testing from which exemption is sought and EPA has adopted test standards and schedules in a final Phase II test rule.

(5) For health effects testing required under paragraph (e) of this section, all persons who manufacture (import) or process 1,2,4-trichlorobenzene, other than as an impurity, after the effective date of this rule (August 21, 1986) to the end of the reimbursement period shall submit letters of intent to conduct testing or exemption applications, submit study plans, conduct tests, and submit data as specified in this section, subpart A of this part, and parts 790 and 792 of this chapter for single-phase rulemaking.

(c) [Reserved]

(d) Environmental effects testing. 1,2,3- and 1,2,4-trichlorobenzenes shall be tested in accordance with this section.

(1) Marine invertebrate acute toxicity testing—(i) Required testing. Testing using measured concentrations, flow through or static renewal systems, and systems that control for evaporation of the test substance, shall be conducted for 1,2,3- and 1,2,4-trichlorobenzenes. Testing shall be conducted with mysid shrimp (Mysidopis bahia) to develop data on the acute toxicity of the above chlorobenzene isomers to marine invertebrates.

(ii) Test standards. The marine invertebrate (mysid shrimp, Mysidopis bahia) acute toxicity testing for 1,2,3- and 1,2,4-trichlorobenzenes shall be conducted in accordance with §797.1930 of this chapter.

(iii) Reporting requirements.

(A) The acute toxicity tests on marine invertebrates shall be completed and the final report submitted to EPA within 1 year of the effective date of the final Phase II test rule.

(B) An interim progress report shall be submitted to the Agency within 6 months after the effective date of the final Phase II rule.

(2) Marine fish acute toxicity testing—(i) Required testing. Testing using measured concentrations, flow through systems, and systems that control for evaporation of the test substance shall be conducted for 1,2,3-trichlorobenzene. Testing shall be conducted with Silversides (Menidia menidia) to develop data on the acute toxicity of 1,2,3-trichlorobenzene to saltwater fish.

(ii) Test standard. The marine fish (silverside minnow, Menida menidia) acute toxicity test shall be conducted for 1,2,3-trichlorobenzene in accordance with §797.1400 of this chapter.

(iii) Reporting requirements.

(A) The marine fish (silversides minnow, Menidia menidia) acute toxicity test shall be completed and the final results submitted within 1 year of the effective date of the Phase II final test rule.

(B) An interim progress report shall be submitted to EPA 6 months after the effective date of the final Phase II rule.

(3) Freshwater fish acute toxicity testing—(i) Required testing. Testing using measured concentrations, flow through systems, and systems that control evaporation of the test substance shall be conducted for 1,2,3-trichlorobenzene. A 96-hour LC50 test shall be conducted with the fathead minnow (Pimephales promelas) to develop data on the acute toxicity of 1,2,3-trichlorobenzene to freshwater fish.

(ii) Test standard. The freshwater fish (fathead minnow, Pimephales promelas) acute toxicity test shall be conducted for 1,2,3-trichlorobenzene in accordance with §797.1400 of this chapter.

(iii) Reporting requirements.

(A) The freshwater fish acute toxicity study shall be completed and the final report submitted to EPA within 1 year of the effective date of the final Phase II test rule.

(B) An interim progress report shall be submitted to EPA 6 months after the effective date of the final Phase II rule.

(4) Freshwater invertebrate acute toxicity testing—(i) Required testing. Testing using measured concentrations, flow through or static renewal systems, and systems that control for evaporation of the test substance shall be conducted for 1,2,3-trichlorobenzene. A 96-hour EC50 shall be conducted for one species of Grammarus to develop data on the acute toxicity of 1,2,3-trichlorobenzene to aquatic freshwater invertebrates.

(ii) Test standard. The freshwater invertebrate (Gammarus sp.) acute toxicity test shall be conducted for 1,2,3-trichlorobenzene in accordance with §795.120 of this chapter.

(iii) Reporting requirements.

(A) The freshwater invertebrate acute toxicity test shall be completed and the final report submitted to EPA within 411 days of the effective date of the final Phase II rule.

(B) An interim progress report shall be submitted to EPA 6 months after the effective date of the final Phase II rule.

(5) Mysid shrimp chronic toxicity testing—(i) Required testing. Testing using measured concentrations, flow through or static renewal systems, and systems that control for evaporation of the test substance shall be conducted for 1,2,4-trichlorobenzene. Testing shall be conducted with mysid shrimp (Mysidopsis bahia) to develop data on the chronic toxicity of 1,2,3-trichlorobenzene, should the acute LC50 of this chemical to mysid shrimp be determined to be less than 1 ppm.

(ii) Test standards. The mysid shrimp (Mysidopis bahia) chronic toxicity test shall be conducted for 1,2,4-trichlorobenzene in accordance with §797.1950 of this chapter. Testing shall also be conducted according to §797.1950 for 1,2,3-trichlorobenzene should the results of testing required by (d)(1)(ii) of this section yield an acute LC50 for this chemical substance of less than 1 ppm.

(iii) Reporting requirements.

(A) The mysid shrimp chronic toxicity test for 1,2,4-trichlorobenzene shall be completed and the final report submitted to EPA within 1 year of the effective date of the final Phase II rule. The mysid shrimp chronic toxicity test for 1,2,3-trichlorobenzene, (required if the LC50 is less than 1 ppm), shall be completed and final report submitted to EPA within 15 months of the effective date of the final Phase II rule.

(B) Progress reports shall be submitted to EPA at 6-month intervals, beginning 6 months after of the effective date of the final Phase II rule and until the final report is submitted to EPA.

(e) Health effects testing—(1) Oncogenicity—(i) Required testing.

(A) A test for oncogenic effects shall be conducted with 1,2,4-TCB in accordance with §798.3300 of this chapter.

(B) The route of administration for the oncogenicity testing for 1,2,4-TCB shall be via the animal feed.

(C) Two rodent species shall be used and one shall be the Fischer-344 rat.

(ii) Reporting requirements.

(A) The oncogenicity test shall be completed and the final results submitted to EPA by June 30, 1994.

(B) Progress reports shall be submitted to the Agency every 6 months after the effective date of the final rule.

(2) [Reserved]

(f) [Reserved]

(g) Effective date.

(1) The effective date of the final phase II rule is August 14, 1987, except for paragraphs (d)(4)(iii)(A) and (e)(1)(ii)(A) of this section. The effective date for paragraph (d)(4)(iii)(A) of this section is March 1, 1990. The effective date for paragraph (e)(1)(ii)(A) of this section is June 12, 1992.

(2) The guidelines and other test methods cited in this rule are referenced as they exist on the effective date of the final rule.

[51 FR 11737, Apr. 7, 1986; 51 FR 18444, May 20, 1986, as amended at 51 FR 24667, July 8, 1986; 52 FR 24465, July 1, 1987; 55 FR 7327, Mar. 1, 1990; 57 FR 24960, June 12, 1992; 57 FR 27845, June 22, 1992; 58 FR 34205, June 23, 1993]