Toxicity criterion

Laboratory experiments using rodents, or the use of gas analysis, tend to be confused by the dominant variable of fuel—air ratio as well as important effects of burning configuration, heat input, equipment design, and toxicity criteria used, ie, death vs incapacitation, time to death, lethal concentration, etc (154,155). Some comparisons of polyurethane foam combustion toxicity with and without phosphoms flame retardants show no consistent positive or negative effect. Moreover, data from small-scale tests have doubtful relevance to real fine ha2ards. 

Vegetable and seed oils as well as some synthetic base stocks present a new class of biodegradable base stocks. These fluids (10) have excellent biodegradation properties as measured by criteria developed by the Environmental Protection Agency (EPA) or Organization of Economic Cooperation and Development (OECD). OECD 301 and EPA 560/6-82-003 measure the biodegradation of lubricants. These tests were developed to measure the degradation of oil, especially two-cycle ok, on waterways. Aquatic toxicity criteria toward fish is also found to be acceptable for this class of fluids as measured by EPA 560/6-82-002 and OECD 203 1-12. 

Despite EPA s urging and guidance, state response was disappointing. A few states adopted large numbers of numeric toxic pohutant criteria, primarily for the protection of aquatic life. Most other states adopted few or no water-quality criteria for priority toxic pohutants. Some rehed on free from toxicity criteria and so-called acLion levels for toxic pollutants or occasionally calculated site-specific criteria. Few states addressed the protection of human health by adopting numeric human health criteria. 

States have made substantial recent progress in the adoption, and EPA approval, of toxic pollutant water-quahty standards. Furthermore, virtually all states have at least proposed new toxics criteria for priority toxic pollutants since Section 303 (c) (2) (B) was added to the CWA in February of 1987. Unfortunately, not all such state proposals address, in a comprehensive manner, the requirements or Section 303 (c) (2) (B). For example, some states have proposed to adopt criteria to protect aquatic hfe, but not human health other states have proposed human health criteria that do not address major exposure pathways (such as the combination of both fish consumption and drinking water). In addition, in some cases final adoption or proposed state toxics criteria that would be approved by EPA has been substantially delayed due to controversial and difficult issues associated with the toxic pollutant criteria adoption process. 

Chemicals on the original list tliat do not meet toxicity criteria but because of their high production volume and recognized toxicity are considered cheiiiicals of concern ("Other chemicals ). 

NCI (1998) National Cancer Institute s Common Toxicity Criteria. Version 2.0. http // ctep.info.nih.gov/CTC3/ctc.htm. 

SSLs are risk-based concentrations derived from standardized equations combining exposure information assumptions with US-EPA toxicity data. For the ingestion, dermal, and inhalation pathways, toxicity criteria are used to define an acceptable level of contamination in soil, based on a one-in-a-million (10 individual excess cancer risk for carcinogens and a Hazard Quotient (HQ) of 1 for noncarcinogens. The hazard quotient is defined as the ratio of an exposure estimate over the Reference Dose or Concentration (Section 5.1), i.e., HQ = Exposure/(RfD or RfC). 

EPA. 1995b. Toxics criteria for those states not complying with Clean Water Act Section 303(c)(2)(B). Federal Register 60 44123. 

These studies were multiple-dose, ascending-dose tolerance studies with three patients per cohort, except at the MTD where usually six or more patients were enrolled. In the event of a DLT, the cohort was to be expanded up to six patients. Dose escalation was to proceed until the MTD was identified, with MTD being defined as the highest dose at which less than two of six patients experienced DLT during, or as a consequence of, treatment with tasidotin. Toxicity was analyzed according to the National Cancer Institute Common Toxicity Criteria, version 2.0... 

National Cancer Institute. 1999. Common Toxicity Criteria, version 2.0. 

Leflunomide can cause abnormal liver function tests, but the risk of serious and non-serious hepatic adverse events is not higher than with methotrexate (71). In the MN301, US301, and MN302 trials, there were abnormal liver enzymes in 6-10% (9,10,12). The co-administration of methotrexate is a risk factor (18,72-74). According to the National Cancer Institute Common Toxicity Criteria, 8.9% of patients developed grade 2 or 3 hepato-toxicity within the first year, mainly within 6 months and in combination with methotrexate, after the start of leflunomide therapy based on liver enzyme determinations (72). The use of folate was also associated with less... 

A Japanese study compared the efficacy and safety of zoledronic acid 4 mg, administered as a 15-minute infusion every month for 1 year, versus placebo in 228 women with bone metastases from breast cancer [21]. Zoledronic acid reduced skeletal-related events by 39% and was well tolerated with a safety profile similar to that of placebo. Only 1 patient in the zoledronic acid group had a notable serum creatinine increase (2.0 mg/ dl) from a baseline of 1.3 mg/ dl compared with 7 patients in the placebo group. Moreover, no patient treated with zoledronic acid developed a grade 3 or 4 serum creatinine increase according to the National Cancer Institute common toxicity criteria, whereas... 

Maximum contaminant level in drinking water Toxic criteria ... 

NATIONAL (coni ) Toxics Criteria for those States Not Complying with CWA Section 303(c)(2)(B)-criterion concentration for priority toxic pollutants Maximum1 ( q/L) Continous0 ( q/L) 40 CFR 131.36 EPA 1992a... 

The number of individual identified hydrocarbon components of the various petroleum products has been estimated at several hundred to over a thousand. Toxicity data are available for about 95 of these, but only about 25 were considered to have sufficient data to develop toxicity criteria according to the Total Petroleum Hydrocarbon Criteria Working Group (TPHCWG 1997b). ATSDR has derived MRLs for 12 of these compounds (anthracene, benzene, ethylbenzene, fluoranthene, fluorene,... 

The health effects of these fractions are discussed in Section 6.2, and details of the selection of the fraction-specific MRLs can be found in Section 6.6. These fraction-specific values are provisional values, reflecting the uncertainty inherent in this approach, as discussed in Section 6.6. Further information on ATSDR MRLs is given in Appendix A, while information on other toxicity criteria such as RfDs and RfCs, is provided in Chapter 7. 

Exposure times and toxicity criteria vary. Compiled from Klein [17], Mason [26], and Ryckman et al. [38],... 

---