Acute toxicity Summaries

In summary, neurotoxic effects of endosulfan are usually apparent only after acute ingestion of relatively high doses. Cumulative neurotoxicity does not appear to be significant. If the animal survives the acute toxic effects, then no long-term neurotoxic effects are evident from behavioral, gross, and microscopic observations. However, some impairment may occur that can be detected only by specialized neurobehavioral testing. 

Adams WJ, Biddinger GR, Robillard KA, Gorsuch JW (1995) A summary of the acute toxicity of 14 phthalate-esters to representative aquatic organisms. Environ Toxicol Chem 14 1569-1574... 

Johnson, W.W. and M.T. Finley. 1980. Handbook of Acute Toxicity of Chemicals to Fish and Aquatic Invertebrates. Summaries of Toxicity Tests Conducted at Columbia National Fisheries Research Laboratory, 1965-78. U.S. Fish Wildl. Serv. Resour. Publ. 137. 98 pp. 

TABLE 5.5. Summary of Clinical Observations from Actual Acute Toxicity Tests... 

TABLE 5.7. Minimal Acute Toxicity Study Summary of the Drug SC-34871... 

Unnecessary animal testing can be avoided by relying on in vitro studies as the first stage acute toxicity and cytocompatibility test for injectable materials (Pearce et al., 2007). Many researchers have utilized in vitro studies to screen the cellular response to CNTs (Raja et al., 2007) and to investigate the various CNT-mammalian cell interactions such as oxidative stress (Manna et al., 2005 Shvedova et al., 2003, 2007), antiproliferative effects (Cui et al., 2005 Garibaldi et al., 2006), decreased cell adhesion (Cui et al., 2005), apoptosis (Bottini et al., 2006 Cui et al., 2005 Jia et al., 2005), and necrosis (Jia et al., 2005). A summary of these in vitro studies are presented in Table 12.1. 

Haskell Laboratory. 1946. Summary of acute toxicity studies on diisocyanates. EPA/OTS Doc 86-870000995. 

Union Carbide. 1968. Summary of acute toxicity and irritancy studies of bis(chloromethyl)ether. Union Carbide Corporation, Danbury, CT. Rpt 31-85 1968. 

For the previously listed reasons, there has been a concerted effort in recent years to modify the concept of acute toxicity testing as it is embodied in the regulations of many countries and to substitute more meaningful methods that use fewer experimental animals. The article by Zbinden and Flury-Roversi is an excellent summary of the... 

In the MPD-SAR study, the USEPA and the European Union compared the predicted and measured ECs for the European Union s new chemicals. The measured ECs were those reported in the European Union s MPD set of experimental toxicity summaries. When the USEPA-predicted ECs for fish and daphnid acute toxicity values were compared to the appropriate MPD-measured acute values, there was, respectively, 77% and 59% agreement, 7% and 19% underprediction, and 16% to 23% overprediction by the USEPA. Potential reasons for the under- and overprediction were investigated, and 17 of the underpredictions and 21 of the overpredictions remained unresolved. Therefore, studies that had potential problems were eliminated, and the analysis was repeated. The highest quality subset of the data indicated 87% and 79% agreement between predictions and measured values. 

In summary, it can be concluded that the acute toxicity of brominated flame retardants is relatively low. The long term effects on the balance of endocrine systems seems to present the greatest danger of these compounds. These endocrine effects need further consideration, since the majority of animals and man are exposed to these brominated flame retardants. The exposure range for humans via the food was calculated as 0.2-0.7 mg per day [96]. 

General and specific considerations concerning labelling requirements are provided in Hazard communication Labelling (Chapter 1.4). Annex 2 contains summary tables about classification and labelling. Annex 3 contains examples of precautionary statements and pictograms which can be used where allowed by the competent authority. The table below presents specific label elements for substances and mixtures that are classified into acute toxicity Categories 1 to 5 based on the criteria set forth in this chapter. 

Acute Toxic Effects of Caffeine Chronic Effects of Caffeine Use Therapeutic Uses of Caffeine Conclusions Summary... 

Summary of Species and Methods for Conducting Acute Toxicity Tests with Fishes, Macroinvertebrates, and Amphibians... 

In summary, alternating, hybrid, or sequential MOPP/AB VD (or MOPP/ABV) regimens have not been shown to be more effective than ABVD. ABVD has the advantage of less acute toxicity, no sterility. 

The history, chemistry, and toxicity of the OP insecticides have been reviewed in the following rcfcrence.s Eto (1961), Fest and Schmidt (1982), Chambers and Levi (1992). H. W. Chambers et al. (2001), J. E. Chambers et id. (2001), and Ecobichon (2001). The OP insecticides display a broad range of acute toxicity levels, and these can be found in Mel.ster (1990). This section provides an overview of the metabolic pathways most commonly seen for compounds within the OP insecticide cla.ss. However, the reader is referred to Aizawa (1982, 1989), J. E. Chambers et al. (1995, 2001), and Dikshith (1991) for more detailed summaries of the metabolic pathways for individual insecticides. 

Nontechnical Summary In this paper, the process of risk assessment with compounds which exhibit chronic but not acute toxicity is first reviewed. The remainder of the paper is spent on reviewing the procedure for quantifying absorption through the skin. The test animal used is the rhesus monkey since previously published work has shown this animal to yield data most similar to man. Data are presented on oryzalin for which dermal absorption was less than 2 percent of the applied dose. The problems and shortcomings of the procedure as well as its advantage (similarity to man) are also discussed. 

A brief summary of the toxicity of the forest herbicide 2,4-D can he presented as follows. Table IV shows the acute LD-50 values of most of the phenoxy herbicices. These range from 300 mg/kg for 2,4,5-T and 375 mg/kg for 2,4-D up to 6400 mg/kg for Blfenox. It Is useful to set the acute oral toxicity for 2,4-D in the context of other phenoxy herbicides and in relation to other pesticides so the public can gain a perception of where 2,4-D fits on a scale of relative values with regard to the onset of acute toxicity symptoms and to show that all phenoxles are not Identical In their acute toxicity but cover a wide range of toxlcltles. 

Accordingly, QS AR modelling of LD5Q data has been described as notoriously difficult (Adamson, Bawden and Saggers, 1984). Nonetheless, despite some controversy, summary parameters such as the LD50 are required by legislative authorities as measures of acute toxicity. 

The first in vivo evidence of the biological inertness of Nafion polymer came from the original product safety testing by du Pont, although these tests were limited to acute toxicity (from oral ingestion) and skin irritation tests (72). Recently, however, one of the authors and previous co-workers carried out the first chronic animal implant studies involving Nafion polymer. These results have been published elsewhere (75) and hence will be describe here in summary only. 

TABLE 2 Summary of structure-activity regressions of measured acute toxicity of PAH s, alkyl halides, cyclic alkanes, and heterocyclic nitrogens to Daphnia pulex (EC50) with several QSAR calculated properties of the chemicals where QSAR LC50 = calculated toxicity to Daphnia - watersolubility MV == molecular volume and the units are indicated as fM or mg L s = the square root of the mean square error for regression. 

In summary, this study has shown that the molecular connectivity model (equation 8) is accurate in predicting acute toxicity in fish for all sorts of hydrocarbons and chlorinated compounds. In addition, its range of applicability is extended to various types of hydrocarbons. Such an accurate, simple, and fast nonempirical model is almost the ideal tool for estimating acute toxicity in fish for the above classes of compounds and its predictive power makes us confident in concluding that these estimates will be accurate. 

In summary, acute-toxicity testing in small mammals such as rats provides a range of valuable information on chemical toxicity, including lethal doses by different routes of exposure, mechanism(s) of lethal toxicity, the extent to which the lethal effect may be reversible in some members of the exposed population while others die, and the relative potencies of toxic chemicals as lethal agents. 

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