Acute Effects on Animals and Humans

Viral transformation of Syrian hamster embryo cells has also been found to be facilitated by trivalent antimony compounds (Fowler and Goering 1991). In workers at antimony smelters, an orange-red to yellowish brown discoloration of the tooth surface ( antimony teeth ) has been observed (Bencze 1994). In 1989, attention was drawn to the possible role of antimony in the sudden infant death syndrome (SIDS) (Richardson 1990). Here, it was postulated that antimony, which was present as a fire retardant in polyvinyl cot mattresses, might be converted by certain molds into tri- 

In comparison to trivalent arsenic, trivalent antimony proved to be five times less cytotoxic in the neutral red assay and one 

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Acute Effects on Animals and Humans Due to the poor solubility of thorium and the low radiotoxicity of natural thorium, no acute effects on humans are reported. Cases of severe pneumoconiosis have been described in photoengravers working with rare earth elements/thorium electrodes. 

Acute Effects on Animals and Humans Eor humans and animals, uranium and its salts are highly chemotoxic. Dermatitis, renal damage and acute arterial lesions may occur. Uranyl compounds readily com-... 

Acute Effects on Animals and Humans Only radiotoxicity has to be considered for Pu and shorter-lived actinides. See the corresponding text for uranium (Chapter 26.2, Section 26.2.6.1) for details. 

Acute effects in animals and humans resulting from a cesium deficiency or related to high cesium intake have not been reported. A high intake of cesium is rapidly excreted via the kidneys (Yamagata etal., 1966), and consequently no reports have been made on any chronic effects due to stable cesium intake. Neither have any mutagenic, carcinogenic or teratogenic effects of stable cesium been either studied or described. 

Clearance of foreign materials (particles) from the lung and airways depends on the function of macrophages, ciliated cells and secretory cells, and on the physical and chemical properties of the alveolar cells. All these are affected by ozone exposure. Single acute exposure of animals and humans to ozone concentrations less than 0.6 ppm have been shown to accelerate clearance of particles from the tracheobronchial tree whereas acute exposures to ozone levels greater than 0.6 ppm caused a delay in particles clearance [79, 261]. Repeated exposures (2 h daily for 14 days) to 0.1 ppm ozone gave rise to acceleration in alveolar clearance of latex particles but had no effect on tracheobronchial clearance. These results, related to morphological studies, are consistent with certain adaptation [278-283]. 

The data in animals are insufficient to derive an acute inhalation MRL because serious effects were observed at the lowest dose tested (Hoechst 1983a). No acute oral MRL was derived for the same reason. The available toxicokinetic data are not adequate to predict the behavior of endosulfan across routes of exposure. However, the limited toxicity information available does indicate that similar effects are observed (i.e., death, neurotoxicity) in both animals and humans across all routes of exposure, but the concentrations that cause these effects may not be predictable for all routes. Most of the acute effects of endosulfan have been well characterized following exposure via the inhalation, oral, and dermal routes in experimental animals, and additional information on the acute effects of endosulfan does not appear necessary. However, further well conducted developmental studies may clarify whether this chemical causes adverse developmental effects. 

Lupien, S. J. and McEwen, B. S. The acute effects of corticosteroids on cognition integration of animal and human model studies. Brain Res. Rev. 24 1-27,1997. 

Data adequacy The key study was well designed and conducted and documented a lack of effects on heart and lung parameters as well as clinical chemistry. Pharmacokinetic data were also collected. The compound was without adverse effects when tested as a component of metered-dose inhalers on patients with COPD. Animal studies covered acute, subchronic, and chronic exposure durations and addressed systemic toxicity as well as neurotoxicity, reproductive and developmental effects, cardiac sensitization, genotoxicity, and carcinogenicity. The values are supported by a study with rats in which no effects were observed during a 4-h exposure to 81,000 ppm. Adjustment of the 81,000 ppm concentration by an interspecies and intraspecies uncertainty factors of 3 each, for a total of 10, results in essentially the same value (8,100 ppm) as that from the human study. ... 

Cognitive effects Animais Cognitive effects of nicotine have been observed in several species, including humans. Experimental studies have focused primarily on the effects on attention and memory. Cognitive benefits are seen after both acute and chronic administration (Levin et al. 1992). In experimental animals, nicotine improves learning and memory on a variety of tasks. Conversely, the nicotinic antagonist mecamylamine... 

Studies of effects on animals following acute, intermediate, and chronic dermal exposure to marine diesel fuel and JP-5 fuel provide evidence for dermal absorption (NTP/NIH 1986). Case reports concerning a man who washed his hair with an unknown amount of diesel fuel (Barrientos et al. 1977) and a man who washed his hands with an unspecified diesel fuel over several weeks (Crisp et al. 1979) provide possible evidence for dermal absorption, but effects resulting from inhalation versus dermal exposure could not be distinguished in these cases. No other data on the absorption of fuel oils following dermal exposure in humans or animals were located. 

The NE system mediates various autonomic, neuroendocrine, emotional and cognitive functions. One of the central roles of NE is response to stress and aversion. This role can be summarized as an activation of response to the acute stress and aversion, followed by decreased reaction to repeated or chronic aversion. Since the response to stress and aversion is a basic part in pathology of mood disorder, NE should play an important role in anxiety, depression and mania. Indeed, this role has been demonstrated in numerous animal and human studies. Majority of antidepressant drugs and mood stabilizers affect NE system as their direct or indirect target. Various medications have different effects on NE neuronal activity. The majority of antidepressants, Li and benzodiazepines suppress NE transmission. Other medications, such as AADs, activate NE neuronal firing activity and NE release. Appropriate combination of different medications, based on the consideration of their effect on NE system, might be critical to obtain good treatment outcome. The combination of SSRIs... 

Toxicity Potential symptoms of overexposure to alicyclic hydrocarbons are irritation of eyes and respiratory system, drowsiness, dermatitis, narcosis, and coma. It also causes adverse effects on the CNS of animals and humans. Acute... 

Acute-Duration Exposure. There are reports on the health effects resulting from acute exposure of humans and animals to benzene via the inhalation, oral, and dermal routes. The primary target organs for acute exposure are the hematopoietic system, nervous system, and immune system. Acute effects on the nervous system and immune system are discussed below under Neurotoxicity and Immunotoxicity. Information is also available for levels that cause death in humans (e.g., Cronin 1924 ... 

Chronic toxicity studies provide information on the long-term health effects of chemical substances. Adverse health effects in exposed animals and subsequent severe damage are known to occur after repeated exposure to low doses over a period of time. The slow accumulation of mercury or lead in the body or after a long latency period from exposure to chemical carcinogens is an example. Chronic or prolonged periods of exposure to chemical substances may also cause adverse effects on the reproduction and behavior of animals and humans. The symptoms caused after chronic exposure usually differ from those observed in acute poisoning from the same chemical. In fact, when exposed to low concentrations of chemical substances, as is the case with chronic toxicity studies, the industrial worker and common public are unaware of the exposure. 

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