oEPA United St Environmental Protection Agency Office of Solid Waste and DIRECTIVE NUMBER: 9444.13(84) TITLE: Michigan Petition: Sb03 Listing APPROVAL DATE: 7-3 EFFECTIVE DATE: 7-3 ORIGINATING OFFICE: El FINAL Office of Solid Waste D DRAFT STATUS: { J [ ] REFERENCE (other documents): A- Pending OMB approval B- Pending AA-OSWER approval C- For review &/or comment D- In development or circulating headquarters OSWER OSWER OSWER VE DIRECTIVE DIRECTIVE Dl ------- PART 261 SUBPART D - LISTS DOC: 9444.13(84) Words: Listing, State Programs Regulations: 40 CFR 261.33(f) Subject: Michigan Petition: SbC>3 Listing Addressee: 'Michigan File Originator: Reva Rubenstein, Toxicologist , Studies and Methods Branch Source Doc: #9444.13(84) Date: Summary: 7-30-84 Sb03 will be listed at 40 CFR 261.33(f) as a hazardous waste based on the findings in the Watt study that Sb03 is oncogenic in female rats. ------- Michigan PetiJtidhFTfcO3~ll»tlng - :--- --•— •••••-- - - - --"- JUL leva Kubenstein, Toxicologlst - Studit* « Methods Brmnch (WH-S62B) ~ ~ ^ * ^ Michigan film Sb03 will be Hated at 40 CF* 261.33f, as a hazardous on the basie oŁ findings in the Watt study that 8bO3 is onco^genic in fenale rats. . In the Watt inhalation study female rats were tested at multiple dose levels. Increased incidence of neoplasms wer« noted at dose levels very close to the occupational PEL (permissible exposure level). Although the study was faulted because there was a lack of adequate control of exposure, the variability of exposure levels was quantified analytically. OTS considers SbOj -_- to b« a qualitative carcinogen with the full dose-response data still to be measured. There is a negotiated testing schedule - -with industry to determine toxicology data including oncogenlcity. Since the only currently available data is on a single sax, I would rate the weight of evidence, at best, as limited to inadequate depending on the experimental quality of the Watt Study (well conducted? proper number of aniaals? length of study? number of controls? spontaneous tumors?) • •*_* & ccs David Friedman Alan Corson John Walker Laurence Rosenstein ------- |