Rodent cancer bioassays indicate that substantial differences exist among PCB mixtures in terms of tumorigenic response, although no bioassay has been conducted with Aroclor 1268. The USEPA has used data from these studies to develop three sets of PCB cancer slope factors (CSFs) ranging from Cancer Slope Factor. A number assigned to a cancer causing chemical that is used to estimate its ability to cause cancer in humans.EPA does not currently have a cancer slope factor for dioxin that can be used to estimate cancer risk. EPA (1991) calculated an oral cancer slope factor for 2,3,7,8-TCDD of 1.5x10s (mg/kg-day) 1 based on a feeding study by Kociba et al.In particular, two recent events warranted recalculating the dioxin cancer slope factor. Dioxin Proposal (Preliminary Evaluation) EPA is proposing a new oral cancer slope factor (CSF) for. tetrachlorodibenzo(p)dioxin (TCDD) that is 8-fold higher than the current value Public comments due 3rd week in August EPAs Science Advisory Board (SAB) Because the a From US EPA, Dec 2003. mechanism of dioxin-mediated cancer is unknown, it is b OCDD TEF TCDD cancer slope factor. uncertain whether these concentrationresponse character- c All other cancer slope factors are from the IRIS database (US EPA Cancer slope factors published by USEPA and other agencies for dioxins are not fully accepted by the toxicology community and considered by others to be excessively conservative (e.g Cole.3. Action levels based on California EPA cancer slope factors. EPA evaluated dioxin exposure from the CDF.The toxicity characteristics of naphthalene represent the highest Cancer Slope Factor (CSF) and lowest reference concentration compared to all other volatile PCOCs selected for this study. View Slope Factors from: Health US EPA. Chemical Name: CAS Number: Oral slope factor (1/mg/kgThe U.S. EPAs Draft Oral Slope Factor (OSF) for 2,3,7,8 -Tetrachlorodibenzo-p- dioxin (TCDD) Glenn Rice, Draft Candidate Cancer Slope Factors 3. In the forenamed document, US EPA sets forth a cancer risk slope factor for dioxin, which was determined based upon epidemiological studies of human dioxin exposure and cancer outcomes. Summary of All Site Cancer ED01s and Slope Factor Calculations from Published Studies ED01/LED01 (95 lower bound) ng/kg Slope factor1, All cancerGAO commented that the data on dioxin levels in food supporting EPAs October 2000 draft reassessment were a significant Tags: cancer factor dioxin.Tags: cancer factor benzene. 2.
Technical Fact Sheet PBDEs In 2014, EPA identified 29 potentially functional, viable alternatives to decaBDE for use in select polyolefins, styrenics 2.1 RfDs, RfCs, Slope Factors, and Unit Risks.
2.2 EPA Cancer Classification.For Scenarios 3 and 4, where congener-specific knowledge is obtained, the total risk should be estimated by using both the PCB slope factor and the Dioxin Toxicity Equivalency Factors (see following table) for those PCBs WHO toxic equivalency factors for various dioxins and dioxin-like compounds41.For known or possible carcinogens, EPA has developed cancer slope factors (CSF) as an estimate of a substances potential to cause additional cancer cases in a population. dioxin cancer slope factor. (alt.) dioxin cancers. MADEP Derived Toxicity Equivalency Factors (TEFs). for Polychlorinated Dioxins and Dibenzofurans. Compound. TEF.Until recently the only cancer slope factor the USEPA published for PAHs was for the chemical benzo[a]pyrene (B[a]P). In the absence of further chemical-specific information, the EPA You are here: EPA Home. Hudson River PCBs. Human Health. PCB Cancer Slope Factors.- Sediment or soil ingestion. - Persistence of dioxin-like, tumor-promoting, or persis- tent congeners in other media. - Early-life exposrue (all path-ways and mixtures). The widely used Toxicity Equivalence Factor (TEF) methodology for assessing the risks from exposure to dioxin and dioxin-like (DL-) compounds isIn 1996, US EPA developed three sets of PCBs cancer slope factors ranging from 0.07 to 2.0 (mg/kg-day)-1 based on the 1996 GE rat study ( US EPA, 1996). first time for TCDD, publication of an oral non-carcinogenic toxicity value2, called a reference dose (RfD) publication of a cancer oral slope factor by the EPA is pending (EPA 2012a). Changes in TCDD toxicity values influence levels of dioxin in soils or sediment that are protective of human health EPA has derived an oral cancer slope factor of 156,000 (mg/kg/day)-1 for 2,3,7,8,-TCDD ( U.S. EPA, 1994c). EPA has assigned the dioxin compounds individual toxicity equivalence factors (TEFs). Suggested Citation:"5 Cancer." National Research Council. 2006. Health Risks from Dioxin and Related Compounds: Evaluation of the EPA Reassessment.Calculations of a slope factor that considers the effects of dioxin on ALL tumor sites, as was done for the human epidemiological data report, Health Risks from Dioxin and Related Compounds: Evaluation of the EPA Reassessment.oral reference dose (RfD) for TCDD and (5) developed a new cancer oral slope factor for TCDD. May 16, 2001 (Washington) -- A draft report to the Environmental Protection Agency concludes that dioxin causes cancer not only in animals but possibly in people as well. The final review from a badly divided scientific advisory board is expected to be on EPA Administrator Christie Todd Whitmans Dr. Timothy Buckley, Chair Dioxin Review Panel Science Advisory Board Environmental Protection Agency (EPA) Washington, DC.In the draft reanalysis, EPA determined an oral cancer slope factor of 1 x 106 per (mg/kg-day). EPA Identified Cancer Risk Slope Factors (Potencies) for Various Acute Non- Cancer Health Based Value (nHBVAcute) Not Derived (Insufficient Data)1. Cancer.- Persistence of dioxin-like, tumor-promoting, or persis- tent congeners in other media. we estimated slope factors and dose 5. A description of the use of toxicity equivalency factors for determining unit risk and cancer potency factors for polychlorinated dibenzo-p-dioxins and dibenzofurans (Appendix A).Chemical Abstract Source Service (CAS). Unit Risk Slope Factor US EPA IARC (g/m3)-1 (mg/kg-day)-1 ClassC ClassC.by the dioxin-like compounds, which was multiplied by the current range of draft cancer slope factors for dioxin (USEPA, 2003).the both the California EPA Public Health Goal of 0.0007 ug/L and the proposed New Jersey Health-based MCL of 0.0013 ug/L are based on the same slope factor In the US, dioxin and furan intake from foods has also significantly decreased in recent years ( EPA 2001).The lifetime excess cancer risk is calculated using the US EPA upper bound cancer risk slope factor EPAs Assumption That the Dose-Response Relationship Is Linear. To estimate a cancer slope factor (CSF) for dioxin using either animal bioassay data or epidemiological data, EPA estimated a point of departure (POD) Cancer Slope Factor (CSF) means a term adopted by EPA to identify the cancer risk associated with a unit dose of a carcinogen. It is the slope of the curve representing the relationship between dose and cancer risk. EPAs draft cancer slope factor for dioxins of 1 x [10.According to Hassur, the weights are based upon the toxicity information used to generate existing toxicity values, such as reference doses and cancer slope factors, which OPPT researchers obtain from a number of sources. The following assumptions were used to calculate the consumption limits: Consumer adult body weight of 72 kg Average fish meal size of 8 oz (0.227 kg) Time-averaging period of 1 month (30.44d) EPAs cancer slope factor for dioxin. One commenter believed EPAs existing slope factor was outdated and that the ongoing dioxin reassessment, or perhaps the Great Lakes Initiative (GLI) cancer slope factor (USEPA, 1995) reflected more current science. Cancer Slope Factor and Unit Risk Factor. What are they? A cancer slope factor gives the percent increase in the risk of getting cancer associated with a dose of a toxin (in mg of toxin per kg of body weight) every day for a lifetime. According to EPA, the slope factor generally approximates or exceeds a 95-percent confidence limit, meaning that there is a greater than 95-percent chance that cancer risks will be less than the upper bound. Source: GAO review of EPA and WHO documents on dioxin reassessment efforts. Slope Factor. 2,3,7,8-tetrachlorodibenzo-p-dioxin.2.1 Toxicity Constants for Noncarcinogens. An RfD embodies EPAs principal approach and rationale for assessing health effects other than cancer. 1) Samples are analyzed for total PCBs (aroclors), the entire PCB mixture is assumed to be equitoxic, and a cancer potency factor from EPA IRIS databaseWhen congener concentrations are available, the slope-factor approach can be supplemented by analysis of dioxin TEQs to evaluate dioxin-like The US EPA has assigned an oral cancer slope factor of 1.5 10 5 mg kg 1 day 1 for TCDD ( US EPA, 2007a). Molecular structures of some important dioxins are presented in Fig. 16. If animals are exposed (Although the ROD also identifies a cancer slope factor of 156,000 per mg/kg-d from the 1986 EPA SPHEM, that value was not used to derive a site-specific dioxin cleanup level because the site adopted the extant EPA 1,000 ppt level.) The U.S. Environmental Protection Agency (US EPA) recommends using cancer slope factors (CSFs) when evaluating potential cancer risks of PCB2003. Meta-analysis of dioxin-cancer dose-response for three occupational cohorts. Environmental Health Perspectives 111 (5), 681-687. This recommendation was based on a cancer slope factor of 1 x 106 (mg/kg/day)-1 and a target cancer risk of 1 in 10,000, and assumed no ongoing source of dioxin contaminated dust [WTCIEA 2003]. Analytical Methods - EPA method 8290 (HRGC/MS) However, for reasons discussed in the Agencys Draft Dioxin Reassessment ( U.S. EPA 1994a), U.S. EPA has not developed reference doses for any of the PCDD or PCDF congeners.However, an oral cancer slope factor is only available for one PAH, benzo(a)pyrene. This cancer slope factor incorporates more recent studies than the 1.5 mg/kg/day-1 cancer slope factor in EPAs IRIS database [9, 10].
Therefore, EHAP concluded that the more significant concern for total dioxin TEQ was based on cancer risk. For example, the U.S. Environmental Protection Agency (U.S. EPA) recent dioxin reassessment, which describes the agencys evaluation of the health risks posed by the PCDD/Fs, is nearlyThis has enormous implications in the derivation of a cancer slope factor from these occupational studies. For calculating cancer risk from exposure to dioxins, in the revised risk assessment EPA used a cancer slope factor for TCDD of 1.56 104 picrograms toxic equivalence/kilogram body weight/day ((pg TEQ/kg-d)1) (USEPA, 1985). Oral Cancer Slope Factor: The U.S. EPAs draft dioxin reassessment efforts produced two upper bound slope factors for estimating human cancer risk from exposure to dioxins The U.S. EPAs draft dioxin reassessment efforts produced two upper bound slope factors for estimating human cancer risk from exposure to dioxinsThis value is based on EPAs draft animal-based cancer slope factor. Cancer slope factor is based primarily on recently published analyses of human studies and is revised upward by a factor of 6 over the 1985 EPA value based on 1978 study in rats.Recommends that the Agency expeditiously move forward with finalization of EPAs Dioxin Reassessment. An oral cancer slope factor is currently available only for benzo[a]pyrene.2010. Recommended Toxicity Equivalence Factors (TEFs) for Human Health Risk Assessments of 2,3,7,8-Tetrachlorodibenzo-p- dioxin and Dioxin-Like Compounds EPA/100/R-10/005. Cancer slope factors (CSF) are used to estimate the risk of cancer associated with exposure to a carcinogenic or potentially carcinogenic substance. A slope factor is an upper bound, approximating a 95 confidence limit ED01/LED01 (95 lower bound) ng/kg Slope factor1, All cancer risk/pg/kg/day Summary of All Site Cancer ED01s and Slope FactorRecommends that the Agency expeditiously move forward with finalization of EPAs Dioxin Reassessment (On the Internet at www.epa .gov/science1/fiscal01.htm).