Investigation on neurotoxicity of occupational exposure to cyclohexane: a neurophysiological study.

Abstract

Objectives-To examine the effect of occupational exposure to cyclohexane on the peripheral nervous system. Methods-A nerve conduction study was performed on 18 workers exposed to cyclohexane in a luggage factory and on age and sex matched occupationally unexposed controls. 12 workers had been exposed to n-hexane (median 2-8 years) before the start of exposure to cyclohexane. To confirm the effect of exposure, a follow up study was performed on nine workers one year after the first study. The mean exposure to cyclohexane was 1 2 years in the first study. A symptom survey was performed. The exposure was measured by air sampling of the breathing zone of each worker. The urinary metabolite cyclohexanol was also monitored. Results-The concentration of airborne cyclohexane ranged from 5 to 211 ppm. The urinary concentration of cyclohexanol ranged from 0-12 to 1 51 mg/I. There was a strong correlation between the cyclohexane exposure in personal air and urinary cyclohexanol. No differences were found in nerve conduction velocities (NCV) between workers exposed to cylohexane and age and sex matched controls. The results of the follow up study showed significant improvements in peroneal motor NCV (P < 0.01) and sural sensory NCV (P < 005) and in ulnar motor distal latency (MDL, P < 005) and peroneal MDL (P < 005) compared with the first study. Although the past n-hexane exposure affected the first neurophysiological study, the effect had disappeared in the second study, one year later. Conclusion-Occupational exposure to the concentrations of cyclohexane experianced in this study had no adverse effects on the peripheral nervous system. (Occup Environ Med 1996;53:174-179)

Solvatochromic parameters for solvents of interest in green chemistry

“…Acetals (glycerol formal, dialkoxymethanes, and dioxolane) have been proposed as solvents for paints and coatings because of their low toxicity and ecotoxicity. 26,27 • Cyclohexane is included as a non-neurotoxic 28 alternative to hexane.…”

Applying a Green Solvent with Microwave, Ultrasound, and Soxhlet Extraction Techniques to Quantify the Slip Additive cis-1,3-Docosenamide and Nine Oxidative Degradation Byproducts in Polypropylene Samples

“…On the other hand, dichloromethane has been reported to have harmful health and environmental effects, including the risk of diseases such as brain and liver cancer and DNA damage [ 37 , 38 , 39 , 40 , 41 ]. Due to the potential dangers associated with cyclohexane and dichloromethane, safer and more environmentally friendly alternatives are sought, such as green solvents [ 37 , 38 , 39 , 40 , 41 , 42 , 43 , 44 ]. One of the leading candidates as a green solvent is limonene, which belongs to the chemical family of monoterpenes ( Figure 1 ) and is a natural compound.…”

Cyclohexane, a Potential Drug of Abuse with Pernicious Effects on the Brain

“…Cyclohexane is a volatile substance that has been implicated in cognitive deterioration (Bespalov et al, 2003 ; Lammers et al, 2009 ). Initially, cyclohexane was considered a safe substitute for benzene and toluene because of its lack of carcinogenic effects and low toxicity (Sikkema et al, 1995 ; Yuasa et al, 1996 ). However, cyclohexane is a strongly lipophilic molecule that can easily diffuse through neural tissue and target numerous brain regions (Figure 1 ).…”

“…The effect of cyclohexane inhalation on the nervous system was first evaluated in shoe workers. After a 6-h exposure to low levels of this solvent, subjects develop dimmed vision (Yasugi et al, 1994 ), sleepiness, dizziness, limb weakness, sensorial disturbances (hypoesthesia and paresthesia), and motor dysfunction of the median, ulnar and peroneal nerves (Mutti et al, 1982 ; Yuasa et al, 1996 ). Volunteers exposed to a moderate concentration of cyclohexane (250 ppm) reported a higher incidence of headache, dry throat and verbal memory impairment than subjects exposed to very low concentrations of the compound (25 ppm; Lammers et al, 2009 ).…”