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Statement of Need: In the past several years, a number of agencies have reviewed the epidemiological evidence and have classified chromium (VI) as a human carcinogen. For example, the Environmental Protection Agency (EPA), the National Institute for Occupational Safety and Health (NIOSH), and the International Agency for Research on Cancer (IARC) have reviewed the epidemiological evidence and have classified chromium (VI) as a human carcinogen. Estimates of the population exposed to hexavalent chromium ;(chromium(VI)? suggest that more than 1 million workers are exposed. The major industries in which excess cancer mortality has been observed are: Chromate production (US, UK, Germany, Japan, Italy); Chrome pigment production (US, Germany, France, Norway, UK); Chrome plating (US, UK, Japan, Italy); Ferrochromium (Sweden, Norway, USSR); and Welding (European countries, WHO) Occupational exposure to chromium (VI) occurs primarily via inhalation but can also occur to a lesser extent through dermal and oral routes. Exposure to chromium (VI) is known to cause lung cancer, bronchial asthma, nasal septum perforations, skin ulcers, and irritative dermatitis. Chromium (VI) causes ulcers of the skin and acute irritative dermatitis among workers exposed to chromium alloys and chromium-plated objects. Inhalation of chromium (VI) aerosols at levels of about 100 ug/m3 may give rise to necrosis in the nasal septum, leading to perforation. Bronchial asthma may occur as a result of inhalation of low levels of chromium (VI) dust or fumes. Such asthma occurs among platers, welders, and ferrochromium workers. In adults, the lethal oral dose of chromates (chromium (VI)) is 50-70 milligrams per kilogram of body weight. The clinical features of acute poisoning are vomiting, diarrhea, hemorrhage and blood loss into the gastrointestinal tract, causing cardiovascular shock. Thirty-five epidemiological studies of lung cancer among workers exposed to chromium have been reviewed extensively by IARC and by other agencies. Thirty-three of these 35 studies showed elevated lung cancer death rates. In at least 20 studies, lung cancer death rates were statistically significantly elevated among workers in either the total cohort, or a subset of the cohort. The Mancuso study (1975) of lung cancer among workers at a U.S. chromate-production plant has been thoroughly reviewed by the Environmental Protection Agency (EPA-Health Assessment Document (HAD), 1984). EPA's evaluation of this study has formed part of EPA's basis for subsequent regulatory activities to reduce exposures to Chromium (VI) - (53 FR 10206, 3/29/88; 57 FR 31576, 7/16/92; 58 FR 65767, 12/16/93). Reviews of updates of another major cohort study (Hayes) are currently underway by the Agency.

Alternatives: Before deciding to publish a proposal, OSHA has considered a number of options including whether or not to develop an ETS, publish an advanced notice of proposed rulemaking, or enforce the existing PEL. Despite the fact that OSHA acknowledges that the risks of serious adverse health affects at the current PEL are significant, OSHA denied the petition for an ETS and initiated section (6)(b) rulemaking. A Section 6(b) rulemaking results in a lower PEL with additional protective provisions and allows scientific evaluation of the data as well as public input into the standard. ^PThe decision to deny the petition for an ETS was based on the following considerations. To promulgate an emergency temporary standard (ETS), section 6(c) of the OSH Act requires that the Secretary determine that "employees are exposed to grave danger from exposure to substances...determined to be toxic...and...that such emergency standard is necessary to protect employees from such danger." The Act further requires that an ETS take affect immediately upon publication in the Federal Register and can remain in effect for no longer than six months after such publication, by which time a permanent standard must be promulgated. Courts have interpreted these provisions to mean that both the "grave danger" from which employees must be protected and the "necessity" for issuing an ETS to protect them must be a danger of incurable, permanent or fatal consequences arising from six months of exposure to the substance. The ETS must be able to achieve the expected benefits in terms of disease avoided within the 6 months. ^PAlthough it is unclear from court decisions whether the requisite "grave danger" implies a risk of harm quantitatively and/or qualitatively more serious than the significant risk required to justify 6(b) standards, it probably does. In light of the legislative history of the provision and the courts' general concern to narrowly limit exceptions to notice and comment procedures conventionally required in rulemakings, the courts have treated an ETS as an extraordinary power to be exercised only when drastic measures are needed. For example, if a risk of one in a thousand of death from cancer over a working lifetime is considered a significant risk, a risk of one in a thousand of death from cancer due to exposure for 6 months, which would be a greater risk, might well constitute a "grave danger." ^PThe petition for the ETS points to the evidence of chromium (VI)-induced lung cancer as the basis for the "grave danger." The risk assessment in the petition indicates that over 100 out of 1,000 workers would be expected to develop lung cancer with a working lifetime hexavalent chromium exposure (45 years) at the current PEL. In addition to cancer risk, there is evidence that other adverse health effects may occur at exposure levels at the current PEL, e.g., nasal septum perforation. ^POSHA evaluated the risk estimates of cancer and other advance health effects due to exposures to chromium (VI) to determine whether such risk constitutes a grave danger. Despite the fact that OSHA acknowledges that the risks of serious adverse health affects that the current PEL are significant, OSHA denied the petition and initiated section (6)(b) rulemaking. A Section 6(b) rulemaking results in a lower PEL with additional protective provisions and allows scientific evaluation of the data as well as public input into the standard. OSHA is preliminarily considering a new TWA PEL in the range of 0.5 - 5.0 ug/m3, measured and reported as chromium (VI). OSHA has initiated a Section 6(b) rulemaking for all hexavalent chromium compounds in all industries. OSHA intends to develop a new rule in the general, agriculture, and maritime industries and to adapt the rule to reflect conditions in the construction industry. OSHA anticipates that these two proposed rules will be published in the Federal Register later in 1997.

Anticipated Costs and Benefits: OSHA prepares an Economic Analysis (EA) to accompany each proposed and final OSHA standard. This report provides details on the industries expected to be affected by a standard; the number of affected workers; the economic and technological feasibility of the standard; and the health benefits, costs, and impacts associated with the standard. A preliminary economic analysis will be published in the Federal Register notice containing the proposed standard for chromium (VI), and the analysis will be subject to public comment during the public hearings. ^PThe principal industrial uses of chromium (VI) are as a structural element and as an anticorrosive. Large quantities are used to make stainless steel and to "chromeplate" regular steel. In both cases, the chromium (VI) protects the iron in steel from corrosion. The principal industrial consumers of chromium are the metallurgical, refractory, and chemical industries. Other important consumers of chromium (VI) are pigment production industries, pigment application industries, and industries using chromium alloys or plated (chromium (VI)) materials. Chromium (VI) is used in industries that produce the following products: ferrochromium, iron and steel, chromates, chromated pigments, plating mixtures, chromium catalysts, colored plastics, and wood preservatives. Chromium (VI) is also used in electroplating, welding, painting, and in printing. Welding on stainless steel will generate chromium (VI) fumes. We are currently reviewing information on chromium (VI) exposures across many industry processes to determine the technological feasibility of achieving compliance with a new PEL. A determination of technological feasibility means that OSHA can demonstrate that current or immediately forthcoming technologies and methods to comply are or will be available for implementation by affected industries. This may include technologies and methods that will reduce worker exposure during existing chromium (VI) processes or substitute technologies and methods that do not make use of chromium (VI). ^PWe are in the process of preparing cost estimates for achieving compliance with a new standard based on the use of those technologies and methods which we believe will be effective in reducing worker exposure. We are aware that several small business entities, e.g., electroplaters, will be covered by a new OSHA standard. We will conduct a regulatory flexibility analysis to determine whether a substantial number of small firms will be significantly affected by the forthcoming chromium (VI) standard. Information provided by employers in this industry sector would help improve the quality of the regulations. ^PThe strength of the epidemiological data leads OSHA to conclude that occupational exposures to chromium (VI) must be reduced. There are several issues that need to be addressed during the rulemaking. Estimates of the number of workers in various industries and the population exposed to various levels need to be refined as does information on current control technologies. Any new PEL for chromium (VI) must be greatly reduced. Assuming that the petitioners' risk estimate is approximately correct, technological and economic feasibility also need to be addressed during the rulemaking.

Risks: OSHA has performed a preliminary quantitative risk assessment using all epidemiological studies for which dose-response information was available. OSHA preliminarily estimates that the risk of excess lung cancer deaths over a working lifetime at the current PEL ranges from 88 to 342 excess lung cancer deaths per thousand exposed workers. OSHA preliminarily estimates that the risk of excess lung cancer deaths over a working lifetime at a new PEL of 0.5 micrograms per cubic meter of air ranges from 0.9 to 4.4 excess lung cancer deaths per thousand exposed workers. This preliminary risk assessment is available in the docket of this rulemaking (Ex. 13-5; Docket H-054a). ^POSHA is of the opinion that the epidemiological data on cancer mortality associated with chromium (VI) exposures are sufficient for the Agency to proceed with reduction of chromium (VI) exposures through regulation. The evidence of material impairment from exposure to chromium (VI) is strong and of high quality. There appears to be no dispute that the current PEL is too high, and the sooner the PELs are reduced, the sooner the risk of death from lung cancer due to occupational chromium (VI) exposure will be reduced. In addition, the number of cases of asthma, dermatitis, nasal septum perforation, and skin ulceration due to chromium (VI) will also be reduced. The risk estimates for chromium (VI) are similar to risk estimates from exposures to other substances that have been regulated through the Section 6(b) rulemaking process.