Toxicity and neurotoxic effects

An occasional common side effect of capsaicin exposure is bronchoconstriction, in asthmatic people, caused by inhaled airborne particles. In nonasthmatic people, this induces a cough. This is prevented by washing the skin surface where capsaicin was applied after 30-40 minutes of exposure. Chronic overdosage can cause chronic gastritis, kidney and liver toxicity, and neurotoxic effects. 

Toxicity and Neurotoxic Effects of Monoterpenoids In Insects and Earthworms... 

Based on these results, one or more toxic hazards may be identified (e.g., cancer, birth defects, chronic toxicity, and neurotoxicity). A primary hazard of concern is one in which there is a serious health consequence (e.g., cancer) that can occur at lower dosages than other serious toxic effects. The primary hazard of concern is chosen for the dose-response assessment. 

Several studies have focused on the cognitive effects of ecstasy, and a review of the adverse effects of MDMA in animals has raised concerns about potential toxicity in humans (57). MDMA can selectively damage brain serotonin (5-HT) neurons in animal brains, even at doses within the range of those typically used recreationally. In many studies, lasting reductions in various brain 5-HT markers have been reported in MDMA-treated animals. Axons of 5-HT neurons were damaged in MDMA-treated animals, including monkeys, and neurotoxic effects of MDMA have been observed in every animal species studied so far. In non-human primates, the toxic dose of MDMA closely approaches the dose used by humans. 

Chronic exposure to maneb has been related to reproductive, embryotoxic teratogenic, and neurotoxic effects. Although the toxicity associated with maneb exposure is low, it has been shown that in combination with other toxicants such as metals, other fungicides and herbicides the effects of maneb may be more pronounced, leading to more severe deficits. 

In vitro systems have been developed to try and understand the mechanism of action of maneb. In particular, the mechanism of toxicity of maneb on the central nervous system using synaptosomal and mitochondrial preparations from brain tissue has been utilized. These studies have shown that maneb has adverse effects on the dopaminergic system, via mechanisms that relate to mitochondrial inhibition and altered neurotransmitter uptake. The genotoxic, cytotoxic, and neurotoxic effects of maneb have been studied using a variety of primary cultures as well as cell lines, including human lymphocytes. As noted above, maneb has little mutagenic potential. 

It is widely recognized that dietary selenium (Se) exhibits a protective effect against Hg toxicity (Sumino et al. 1977). Reduction of the lethal and neurotoxic effects of methylmercury compounds has been noted. The reason... 

Fragrance products (cologne and toilet water) containing mixtures of aldehydes, esters, terpenes, and carboxylic acids were found to induce acute respiratory and neurotoxic effects in laboratory animals. These effects were not predicted from a consideration of the toxicities of the individual chemicals in the amounts present. ... 

Cisplatin and related compounds have also been evaluated in the management of metastatic melanoma. The effectiveness of platinum compounds as single agents is limited, with response rates reported to be less than 10%. The toxicities of cisplatin can be problematic, and include acute and delayed nausea and vomiting, renal toxicity, and neurotoxicity. 

Haemopoietic effects, gastrointestinal toxicity and neurotoxicity reported when used therapeutically. LD50 (rat, orl) 1784 mg/kg. Mutagen. Exp. reprod. and teratogenic effects. Probable human carcinogen (lARC 2A). KC0190000 2 -Deoxy-2"-(dimethylamino) NK 611 [105655-99-0]... 

Cumulative organ toxicity also presents a significant obstacle for effective chemotherapy. In many cases, the severity of the toxicity impedes the broader use of an agent. Other specific toxicities are associated with specific agents, for example cardiotoxicity with adriamycin (32), renal toxicity with i7j -platinum (28), and neurotoxicity with vincristine (49). 

Dioxins are prominent members of the class of polychlorinated hydrocarbons that also includes diben-zofuran, biphenyls and others. Dioxins are highly toxic environmental contaminants. Like others small planar xenobiotics, some dioxins bind with high affinity to the arylhydrocarbon (Ah) receptor. Dioxins activate the receptor over a long time period, but are themselves poor substrates for the enzymes which are induced via the Ah-receptor. These properties of the dioxins and related xenobiotics may be important for the toxicity of these compounds. Dioxins like 2,3,7,8-tetrachloro-p-dibenzodioxin can cause persistent dermatosis, like chloracne and may have other neurotoxic, immunotoxic and carcinogenic effects. 

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. 

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