In 1976, President Gerald R. Ford signed the Toxic Substances Control Act (15 U.S.C. 2601 et seq . ; TSCA). Thirty-five years of experience with TSCA implementation and enforcement have demonstrated the strengths and weaknesses of the law and led many to propose legislative changes to TSCA's core provisions in Title I. On April 15, 2010, Senator Lautenberg introduced comprehensive legislation ( S. 3209 ) to amend TSCA, and Representatives Waxman and Rush posted draft TSCA reform legislation on the home page of the House Committee on Energy and Commerce. The latter House draft was subjected to stakeholder comments and critiques in a series of meetings during the spring. The proposal was revised and introduced July 22, 2010, as H.R. 5820 . This report compares key provisions of S. 3209 , as introduced, H.R. 5820 , as introduced, and current law. The major provisions of TSCA Title I are summarized in Tables 1 through 6. The first column of each table describes the provisions of TSCA Title I. The second and third columns summarize provisions of S. 3209 and H.R. 5820 , respectively, that are related to the TSCA provisions in the first column. New provisions that would be added to the end of TSCA Title I by one or both proposals—for example, those related to reduced use of animals for toxicity testing—are summarized in Table 6 . The basic organization of TSCA would be unaffected by the proposals. For example, provisions related to testing would still be in Section 4, requirements for notifying EPA when a new chemical or new use is proposed would still be in Section 5, and regulatory authorities would remain in Section 6. Also unaffected would be recently enacted changes, such as a provision that bans exports of elemental mercury. However, most of the original Title I provisions would be amended or deleted by the proposed legislation, and both proposals would make substantial changes to current law. For example, both proposals would shift the burden of demonstrating the safety of chemicals from the U.S. Environmental Protection Agency (EPA) to manufacturers and processors, and would prohibit manufacture, processing, and distribution of any chemical substance or mixture for any use for which safety had not been demonstrated to EPA's satisfaction. Exemptions from prohibitions would be allowed for particular uses only if a use was "in the paramount interest of national security"; lack of the chemical use "would cause significant disruption in the national economy"; the use was essential or critical and there was no safer feasible alternative; or the chemical use, relative to alternatives, provided a benefit to health, the environment, or public safety. In addition, the proposals would require data development and submission to EPA for all chemicals in commerce, rather than only for chemicals that EPA has found "may present an unreasonable risk of injury to health or the environment" and for which EPA has demonstrated a data need, as required under current law. The proposed amendments to TSCA would increase public access to information about EPA's decisions as well as to some information about chemicals that currently is treated as confidential business information. Based on the data received, EPA would be directed to target chemicals with particular characteristics (for example, persistence in the environment) for early evaluation and possible risk management. Once a chemical has been evaluated and EPA has determined whether (or under what conditions) use of the chemical was safe, the proposals would require risk management action to promptly reduce use of, or exposure to, the chemicals of highest concern, and to encourage development of "safer alternatives." Action would be expedited by allowing EPA to issue administrative orders instead of rules (which must be promulgated under current law), exempting certain EPA decisions from judicial review, and removing certain TSCA requirements that are in addition to requirements specified in the Administrative Procedure Act (5 U.S.C. 553) for notice and comment rulemaking. The scope of EPA oversight also would be expanded by S. 3209 and H.R. 5820 . Both include language that would allow EPA to define various distinct forms of substances that are the same in terms of molecular identity but differ in structure and function, such as manufactured nanoscale forms of carbon and silver. Both proposals also broaden the scope of environmental risks that EPA may manage to include risks found in the indoor environment; currently, TSCA applies only to chemicals in the ambient environment. The proposed amendments also appear to more clearly authorize EPA control of risks posed by articles formed from a substance. Both proposals would authorize EPA activities not currently authorized under TSCA to allow implementation of international agreements pertaining to persistent organic pollutants and other hazardous chemicals. For example, the proposals would authorize EPA to regulate chemicals manufactured solely for export. The authority provided by S. 3209 is specific to three international agreements, while the authority provided by H.R. 5820 applies more generally to any international agreement concerning chemicals. Both proposals would prohibit production and use of some chemicals, but S. 3209 prohibits production and use when it is inconsistent with U.S. obligations under the treaties that have entered into force for the United States. H.R. 5820 directs EPA to ban activities only for specified chemicals that are intentionally produced and are not already regulated under U.S. law. The effect of TSCA on state and local chemical laws also would be modified by the proposals. Current law, TSCA Section 18, generally does not preempt state laws. However, if EPA requires testing of a chemical under section 4, no state may require testing of the same substance for similar purposes. Similarly, if EPA prescribes a rule or order under section 5 or 6, no state or political subdivision may have a requirement for the same substance to protect against the same risk unless the state or local requirement is identical to the federal requirement, is adopted under authority of another federal law, or generally prohibits the use of the substance in the state or political subdivision. TSCA authorizes states and political subdivisions to petition EPA, and authorizes EPA to grant petitions, by rule, to exempt a law in effect in a state or political subdivision under certain circumstances. A petition may be granted if compliance with the requirement would not cause activities involving the substance to be in violation of the EPA requirement, and the state or local requirement provides a significantly higher degree of protection from the risk than the EPA requirement does, but does not "unduly burden interstate commerce." The proposed amendments would simplify this section of TSCA. S. 3209 provides that TSCA would not preempt laws relating to a chemical substance, mixture, or article unless they were less stringent than federal law. H.R. 5820 provides that the act does not affect the right of a state or locality to adopt or enforce its own requirements unless compliance with both the state or local requirements and TSCA is "impossible." Several novel provisions are included in both legislative proposals. One provision, for example, would require definition and listing of localities with populations that are "disproportionately exposed" to toxic chemicals. EPA would be directed to develop an action plan to reduce exposure in such "hot spots." Another provision would direct the EPA Administrator to coordinate with the Secretary of Health and Human Services to conduct a biomonitoring study to determine whether a chemical that research has indicated may be present in human biological substances and that may have adverse effects on human development in fact is present in pregnant women and infants. If the chemical is found to be present, manufacturers and processors must disclose to EPA, commercial customers, consumers, and the general public all known uses of the chemical and all articles in which the chemical is expected to be present. Children's environmental health also is addressed by the bills. Both proposals would establish a children's environmental health research program at EPA and an advisory committee to provide independent advice relating to implementation of TSCA and protection of children's health. The proposals also would establish at least four research centers to encourage the development of safer alternatives to existing hazardous chemical substances. "Green chemistry and engineering" also would be promoted through grants. Finally, the proposed amendments would direct EPA to minimize use of animals in toxicity testing. An advisory committee would be established to publish a list of testing methods that reduce use of animals. So-called "alternative testing methods" have been under development for many years, but remain a minor component of toxicity testing programs. The proposals differ in many details (which will not be discussed here) and in several noteworthy ways that are summarized in Tables 1 through 6. One significant difference is the length of time each proposal allows before all chemicals in commerce must be tested for toxicity. For all existing chemicals that have not been placed on a priority list, data sets must be submitted within 14 years of the date of enactment of S. 3209 . H.R. 5820 allows five years for data development. Another difference that may spur debate is the definition of the safety standard that chemicals are required to meet. H.R. 5820 would require that a chemical substance or mixture "is not reasonably anticipated to present a risk of injury to health or the environment," "provides a reasonable certainty of no harm, including to vulnerable populations," taking into account aggregate and cumulative exposure to a chemical, "and protects the public welfare from adverse effects, including effects on the environment." S. 3209 would require that EPA ensure "aggregate exposure and cumulative exposure of the general population or of any vulnerable population to the chemical substance or mixture presents a negligible risk of any adverse effect." Although they propose somewhat different safety standards, both proposals propose a health-based standard, which might generally discourage consideration of other factors, such as benefits of chemical use or costs of alternative chemicals in similar applications. (However, EPA would be authorized to consider such benefits and costs under certain circumstances. See in Table 4 under the heading "Exceptions to prohibitions and other restrictions" the description of TSCA 6(e) as it would be amended.)