Legal Standards on TSCA Section 4, 8(a), 8(c), 8(d) and Applicability to a Section 21 Petition
	
1.  Legal standard regarding TSCA section 8(a) rules. 
	Section 8(a) of TSCA authorizes the EPA Administrator to promulgate rules under which manufacturers and processors of chemical substances must maintain such records and submit such information as the EPA Administrator may reasonably require. Regarding mixtures, section 8(a) of TSCA authorizes the EPA Administrator to promulgate rules under which manufacturers and processors of mixtures must maintain such records and submit such information to the extent the EPA Administrator determines the maintenance of records or submission or reports, or both, is necessary for the effective enforcement of TSCA. Section 8(a) of TSCA generally excludes small manufacturers and processors of chemical substances or mixtures from the reporting requirements established in TSCA section 8(a). However, EPA is authorized by TSCA section 8(a)(3)(A)(ii) to require TSCA section 8(a) reporting from small manufacturers and processors with respect to any chemical substance or mixture that is the subject of a rule proposed or promulgated under TSCA section 4, 5(b)(4), or 6, or that is the subject of an order in effect under TSCA section 5(e), or that is the subject of relief granted pursuant to a civil action under TSCA section 5 or 7. The standard for determining whether an entity qualifies as a small manufacturer is found at 40 CFR 704.3. 
      Section 21(b)(4)(B) of TSCA provides the standard for judicial review should EPA deny a request for rulemaking under TSCA section 8(a): ``If the petitioner demonstrates to the satisfaction of the court by a preponderance of the evidence that ...there is a reasonable basis to conclude that the issuance of such a rule ...is necessary to protect health or the environment against an unreasonable risk of injury,'' the court shall order the Administrator to initiate the requested action. 15 U.S.C. 2620(b)(4)(B).

2. Legal standard regarding TSCA section 8(d) rules. 
	Section 8(d) of TSCA authorizes EPA to require the submission of unpublished health and safety studies initiated or conducted by, or known to or reasonably ascertainable by, manufacturers, processors, and distributors of chemical substances or mixtures. Studies may be excluded ``if the Administrator finds that submission of lists of such studies are unnecessary to carry out the purposes of [TSCA].'' 15 U.S.C. 2607(d)(1). 
      Section 21(b)(4)(B) of TSCA provides the standard for judicial review should EPA deny a request for rulemaking under TSCA section 8(d): ``If the petitioner demonstrates to the satisfaction of the court by a preponderance of the evidence that ...there is a reasonable basis to conclude that the issuance of such a rule ...is necessary to protect health or the environment against an unreasonable risk of injury,'' the court shall order the Administrator to initiate the requested action. 15 U.S.C. 2620(b)(4)(B).
      
3. Legal standard regarding TSCA section 8(c) call-in. 
      TSCA section 8(c) requires manufacturers, processors, and distributors of chemical substances or mixtures 1) to keep records of significant adverse reactions to health or the environment, as determined by the Administrator by rule, alleged to have been caused by the chemical substance or mixture and 2) to permit inspection and submit copies of such records upon request of any duly designated representative of the Administrator. EPA's implementing regulations are at 40 CFR part 717. 
	 Among the actions potentially available under TSCA section 8, only rules are proper objects of a TSCA section 21 petition. Pursuant to TSCA section 8(c) and EPA's implementing regulations at 40 CFR 717.17, allegations of adverse reactions are not called in by rule. In contrast, other provisions of TSCA -- including part of TSCA section 8(c) -- require or authorize the Administrator to act by rule. Section 21 of TSCA allows any person to petition ``to initiate a proceeding for the issuance, amendment, or repeal of a rule under section 2603, 2605, or 2607." 15 U.S.C. 2620(a). EPA interprets TSCA section 21 to apply only to the enumerated actions. 
      
4. Legal standard regarding TSCA section 4 rules. 
      To issue a TSCA section 4 test rule, EPA must find that data and experience are insufficient to reasonably determine or predict the effects of a chemical substance or mixture on health or the environment and that testing of the chemical substance or mixture is necessary to develop the missing data. 15 U.S.C. 2603(a)(1). In addition, EPA must find either that the chemical substance or mixture may present an unreasonable risk of injury or that the chemical substance or mixture is produced in substantial quantities and may either result in significant or substantial human exposure or result in substantial environmental release. 15 U.S.C. 2603(a)(1).
	In the case of a mixture, EPA must also find that ``the effects which the mixture's manufacture, distribution in commerce, processing, use, or disposal or any combination of such activities may have on health or the environment may not be reasonably and more efficiently determined or predicted by testing the chemical substances which comprise the mixture.'' 15 U.S.C. 2603(a)(2).
	TSCA section 21 omits the finding that ``testing is necessary to develop the data'' from the findings that a petitioner must demonstrate in order for a court to require EPA to initiate TSCA section 4 rulemaking. 15 U.S.C. 2620(b)(4)(B)(i). Nonetheless, EPA believes TSCA section 21(b)(4) is best interpreted as incorporating this finding. The alternative would be to read the statute as empowering a court to require EPA to initiate a rulemaking even where the Agency could not make proposed findings consistent with TSCA section 4 or take final action on the rule. EPA's interpretation is supported by legislative history (Ref. 1).
	TSCA section 21(b)(4)(B)(i) provides for judicial review of a petition to promulgate a TSCA section 4 rule for chemical substances. In contrast, TSCA section 21 does not provide for judicial review of a petition to promulgate a test rule for mixtures. Section 3 of TSCA gives distinct definitions for "chemical substance" and "mixture", and section 21(b)(4)(B)(i) of TSCA specifies that the court's review pertains to application of the TSCA section 4 factors to chemical substances. Moreover, TSCA section 21(b)(4)(B)(i) does not contain the additional finding that TSCA section 4 requires for issuing a test rule for mixtures (that the effect may not be reasonably and more efficiently determined or predicted by testing the chemical components). Congress left the complex issues associated with the testing of mixtures to the Administrator's discretion.
