Staggered gait

Acute benzene poisoning results in CNS depression and is characterized by an initial euphoria followed by staggered gait, stupor, coma, and convulsions. Exposure to approximately 4000 ppm benzene results in complete loss of consciousness. Insomnia, agitation, headache, nausea, and drowsiness may persist for weeks after exposure (126). Continued inhalation of benzene to the point of euphoria has caused irreversible encephalopathy with tremulousness, emotional lability, and diffuse cerebral atrophy (125). In deaths arising from acute exposure, respiratory tract infection, hypo- and hyperplasia of sternal bone marrow, congested kidneys, and cerebral edema have been found at autopsy. 

Barbiturates create a sense of relaxation, reduce tensions, and induce euphoria as measured by standardized scales. Concentration is greatly reduced, as is judgment, and irritability often results. Chronic use slurs speech and leads to incoherence, staggered gait, and tremors. 

Rats were exposed to vapor concentrations of either 260 or 5,900 ppm hexachloroethane for 8 hours (Weeks et al. 1979). The 5,900 ppm vapor concentration was generated at 50 C and crystallized as it entered the exposure chamber. At the higher concentration the exposed animals showed signs of distress (staggering gait) during exposure, and 2 of 6 were dead at the end of 8 hours. No animals died at the lower exposure concentration. 

Acute 8-hour exposures to 5,900 ppm, but not 260 ppm, resulted in a staggering gait in one of six rats (Weeks et al. 1979). Tremors were also noted in pregnant rats exposed 6 hours per day to 260 ppm starting on the 6th day of an 11-day exposure period but not in animals exposed to 15 or 48 ppm (Weeks et al. 1979). Based on the NOAEL for neurological effects, an acute inhalation MRL of 6 ppm was calculated, as described in the footnote in Table 2-1. 

Acute exposure of sheep to 500 mg/kg hexachloroethane resulted in tremors of the facial muscles immediately after the exposure (Fowler 1969b). In sheep that were suffering from liver fluke infections, the neurotoxicity of hexachloroethane was even more pronounced. A dose of 170 mg/kg given for treatment of the fluke infection rendered 2 of 15 sheep immobile and unable to stand on the day after treatment, and a dose of 338 mg/kg affected 6 of 15 animals. Tremors of the facial muscles, neck, and forelimbs were apparent. The animals that were able to stand had a staggering gait, and when they fell, they were unable to... 

Neurotoxicity. No information is available on neurotoxic effects of hexachloroethane in humans following any route of exposure. Acute inhalation exposure in rats caused staggering gait after exposure to high concentrations (5,900 ppm) (Weeks et al. 1979). The usefulness of this data is limited since this concentration was lethal. Tremors have been reported at 260 ppm but not 48 ppm following inhalation exposure of rats in a developmental study and in a study of 6-weeks duration (Weeks et al. 1979). The lack of tremors at 48 ppm in the developmental study serves as the basis for the acute inhalation MRL, and the lack of tremors at 48 ppm in the 6-week study serves as the basis for the intermediate inhalation MRL. One study that evaluated spontaneous motor activity and avoidance behavior in rats during 6 weeks of exposure to 260 ppm hexachloroethane vapors did not reveal adverse effects of hexachloroethane on these neurobehavioral functions (Weeks et al. 1979). 

Convulsions, salivation, lachrymation, staggering gait, hypothermia, and shallow breathing were also recorded in bullocks treated topically with a concentrated endrin solution (Pandey 1978). 

Human exposure to very high concentrations, approximately 20,000 ppm, is fatal in 5-10 minutes. Concentrations of 7500ppm are dangerous to life within 30 minutes. Convulsive movements and paralysis followed by unconsciousness follow severe exposures. Brief exposure to concentrations in excess of 3000 ppm is irritating to the eyes and respiratory tract continued exposure may cause euphoria, nausea, a staggering gait, and coma. Inhalation of lower concentrations (2 5 0-5 00 ppm) produces vertigo, drowsiness, headache, and nausea, whereas 2 5 ppm for 8 hours is without clinical effect. 

Exposed workers have complained of a burning sensation in the mouth, dry throat, and thirst somnolence, staggering gait, and coma have been observed with more intense exposures. Most signs and symptoms of overexposure are due to the loss of oxygen-carrying capacity of the blood. 

In rats, the LDso for 4 hours was 4420 ppm effects included irritation of mucous membranes, increased respiration, incoordination, staggering gait, weakness, partial skeletal muscle paralysis, light to severe cyanosis, and mild to heavy sedation. ... 

Accidental exposure of a pilot during a fuel leak to JP-4 at levels estimated to be between 3000 and 7000 ppm produced signs of neurological intoxication, but cardiovascular and pulmonary function appeared normal on clinical examination. The pilot had a staggering gait, mild muscular weakness, decreased responsiveness to painful stimuli, and slight slurring of speech. The effects were not evident 36 hours after exposure. 

Definite mental confusion, considerable incoordination and staggering gait There may be complaints of nausea and nervousness many suffer headache... 

Nausea and pronounced confusion considerable incoordination and staggering gait Nervousness and fatigue may last several days there may be marked insomnia... 

Wernicke s disease is characterized by confiision, loss of memory, staggering gait, and an inability to focus the eye (USDHHS, 1987a, 1990). In the absence of permanent brain damage, Wernicke s disease is reversible by giving the patient Vitamin B,. 

All the barbiturates possess the properties of CNS depressants. Thus, in moderate doses they produce a drunken euphoric state. Similar to alcohol, barbiturates may produce a loss of motor coordination, a staggering gait, and slurred speech. Loss of emotional control and behavioral disinhibition arc also characteristic cfTccts. Sedation and sleep are produced by increased doses, and higher doses produce surgical anesthesia. Physiological effects include respiratory depression, which is responsible for most of the overdose deaths associated with barbiturates. In addition some depression of heart rate, blood pressure, and gastrointestinal activity is noted at higher doses. 

Acetylene is not toxic below its lower explosive limit of 25 000 ppm. In the presence of adequate oxygen, acetylene causes a slight intoxication at 100 000 ppm, which leads to a staggering gait and general incoordination as the concentration increases to 300 000 ppm. Unconsciousness occurs in 5-7 min at 350 000 ppm. Full anesthesia occurs at 800 000 ppm. Anesthetic concentrations of acetylene do not affect heart, liver, or kidney function but do result in an increase in blood pressure. 

Exposure to high concentration (severe exposure) of mercaptans may produce central nervous system effects such as headache, staggering gait, muscular weakness, tremors, lung edema, convulsions, and paralysis of the respiratory center. Long-term health effects are not well documented. 

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