<unk>  is a form of toxicity in which a biological, chemical, or physical agent produces an adverse effect on the structure or function of the central and/or peripheral nervous system. It occurs when exposure to a substance – specifically, a neurotoxin or neurotoxicant– alters the normal activity of the nervous system in such a way as to cause permanent or reversible damage to nervous tissue. This can eventually disrupt or even kill neurons, which are cells that transmit and process signals in the brain and other parts of the nervous system.<unk>  can result from organ transplants, radiation treatment, certain drug therapies, recreational drug use, and exposure to heavy metals, bites from certain species of venomous snakes, pesticides, certain industrial cleaning solvents, fuels and certain naturally occurring substances. Symptoms may appear immediately after exposure or be delayed. They may include limb weakness or numbness, loss of memory, vision, and/or intellect, uncontrollable obsessive and/or compulsive behaviors, delusions, headache, cognitive and behavioral problems and sexual dysfunction. Chronic mold exposure in homes can lead to<unk>  which may not appear for months to years of exposure. All symptoms listed above are consistent with mold mycotoxin accumulation. The term<unk>  implies the involvement of a neurotoxin; however, the term neurotoxic may be used more loosely to describe states that are known to cause physical brain damage, but where no specific neurotoxin has been identified. The presence of neurocognitive deficits alone is not usually considered sufficient evidence of<unk> , as many substances may impair neurocognitive performance without resulting in the death of neurons. This may be due to the direct action of the substance, with the impairment and neurocognitive deficits being temporary, and resolving when the substance is eliminated from the body. In some cases the level or exposure-time may be critical, with some substances only becoming neurotoxic in certain doses or time periods. Some of the most common naturally occurring brain toxins that lead to<unk>  as a result of long term drug use are amyloid beta (Aβ), glutamate, dopamine, and oxygen radicals. When present in high concentrations, they can lead to<unk>  and death (apoptosis). Some of the symptoms that result from cell death include loss of motor control, cognitive deterioration and autonomic nervous system dysfunction. Additionally,<unk>  has been found to be a major cause of neurodegenerative diseases such as Alzheimer's disease (AD).
Neurotoxicity
Cardiotoxicity
Hepatotoxicity
Pulmonary toxicity
Nephrotoxicity
Bone marrow suppression
Phototoxicity
Toxicity