The neurotoxicity of n-pentane, n-hexane, and n-heptane have been studied in Wistar strain male rats after exposure to 3000 ppm of n-pentane, n-hexane, or n-heptane for 12 hours a day for 16 weeks. The nerve conduction velocity and the distal latency were measured before the beginning of the exposure and after exposure for four, eight, 12, and 16 weeks. The experiment showed that n-hexane disturbed the conduction velocity of the motor nerve and the mixed nerve and prolonged the distal latency in the rat9s tail, but that n-pentane and n-heptane did not. The light and electron microscopic examination showed that the peripheral nerve, the neuromuscular junction, and the muscle fibre of the rats exposed to n-hexane were severely impaired, but those of the rats exposed to n-pentane or n-heptane showed no particular changes even after 16 weeks of exposure. These results show that n-hexane is far more toxic to the peripheral nerve of the rat than n-pentane or n-heptane. It is necessary to study the neurotoxicity of other petroleum hydrocarbons, since some reports suggest that petroleum solvents might possibly contain neurotoxic hydrocarbons other than n-hexane.
(1981). A Comparative Study of the Toxicity of n-Pentane, n-Hexane, and n-Heptane to the Peripheral Nerve of the Rat. Clinical Toxicology: Vol. 18, No. 12, pp. 1395-1402.
Journal of Occupational HealthVolume 38, Issue 4 p. 196-197 Short CommunicationFree Access A Simple Method for Calculating the Exact Confidence Interval of the Standardized Mortality Ratio with an SAS Function Jian Sun, Jian Sun Department of Hygiene, Nagoya University School of MedicineSearch for more papers by this authorYuichiro Ono, Yuichiro Ono Department of Hygiene, Nagoya University School of MedicineSearch for more papers by this authorYasuhiro Takeuchi, Yasuhiro Takeuchi Department of Hygiene, Nagoya University School of MedicineSearch for more papers by this author Jian Sun, Jian Sun Department of Hygiene, Nagoya University School of MedicineSearch for more papers by this authorYuichiro Ono, Yuichiro Ono Department of Hygiene, Nagoya University School of MedicineSearch for more papers by this authorYasuhiro Takeuchi, Yasuhiro Takeuchi Department of Hygiene, Nagoya University School of MedicineSearch for more papers by this author First published: October 1996 https://doi.org/10.1539/joh.38.196Citations: 27AboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinked InRedditWechat No abstract is available for this article.Citing Literature Volume38, Issue4October 1996Pages 196-197 ReferencesRelatedInformation
We examined the relationship between muscle injection of drugs into the quadriceps and its contracture.Subjects were children who had received medication at a clinic during the period from January 1967 to December 1970. Among the patients of the clinic, a high incidence of quadriceps contracture had been observed during the period.As basic data, we took the results of interviews with the subjects, the results of clinical examinations for quadriceps contracture, and medical records of the subjects which had been kept in the clinic.The following results were obtained.1) There were no abnormalities among the subjects who had never been injected in the quadriceps muscle. The incidence and the severity of quadriceps contracture were closely related to the total amount of the drugs injected into the muscles.2) The total numbers of injections of the following drugs were significantly larger in subjects with symptoms of contracture than in subjects without any symptoms.The drugs were Terramycin (Ox-tetracycline), Obelon (Sulpyrin, Aminopropyrin, Theoclate diphenyl pyralin), Chloromycetinsol (Chloramphenicol), Atarax-P (Hydroxyzin hydrochloride), Gammavenin (immuno-Globlin), Panvitan (Vitamin A-D), 10%-Pantocin (Pantethine) and Phenobarbital (Phenobarbital natrium).3) It was revealed by means of quantification theory type II analysis that the main attributable factors of muscle contracture might be the age when the subjects had been injected for the first time, the total number of Terramycin+Obelon injections, and the experience of injection of 10% Pantocin or Phenobarbital, but sex and the year of the beginning of injection might be ignored.Discrimination based on these results between the two groups, a normal group and a moderate or more severe symptomatic group showed reasonable sensitivity and specificity.
1) Two cases of aplastic anemia were found among over-glaze decoration workers in potteries. They had used solvents containing benzene for treating liquid gold (a kind of pigment) or for wiping off the varnish (an adhesive for printing transfer papers). So, the relationship between aplastic anemia of the two cases and their benzene exposure were investigated. Case 1: a 49 year-old man who had been exposed to benzene occasionally for one or two months in 1967 and four hours a day for five months from October, 1971 to February, 1972. He had been in good health before he began to complain of headache in March, 1972. His health conditions acutely worsened and he was admitted to a hospital with a diagnosis of aplastic anemia on March 13, 1972 (Table 1). His severe anemia remitted six months after admission (Fig. 1). The solvent used by him contained 90% of benzene and 10% of toluene. He had used 50 to 100 ml of the solvent a day. It was estimated from the working conditions investigated in the similar factories that he might have been exposed to benzene continuously at about 0.5 ppm and intermittently even at 7.5 to 30 ppm or more. Case 2: a 60 year-old woman who had been exposed to benzene nine hours a day from 1952 to the spring of 1967. She had often complained of nausea, vomiting, fever and pollakisuria since the summer of 1968, and she was admitted to a hospital in March, 1969. She was diagnosed as aplastic anemia at that time (Table 2). She died three months after her admission in spite of medical treatment (Fig. 2). The autopsy revealed that her bone marrow was hypoplastic. She had daily used about 125 ml of the solvent containing benzene. It was estimated from the working conditions investigated in the similar factories that she might have been exposed to 7.5 to 30 ppm or more of benzene almost continuously throughout her working time. Judging from the relationship of the clinical course and the benzene exposure in the two cases, and from the results of other reports on the benzene poisoning (Table 5), it could be considered that aplastic anemia in both cases was caused by benzene. 2) The working conditions, especially benzene exposure, were investigated in six over-glaze decoration factories. Factories A and B were investigated in March, 1977, and factories C, D, E and F in July, 1977. It was revealed that benzene had been used in all the factories (Table 3), which were poorly ventilated. Above 150 ppm of benzene were detected close to the respiratory zone of a worker in factory B (Table 4, Fig. 5). Benzene above 25 ppm (the ceiling value of MAC recommended by the Japan Association of Industrial Health) were often detected in other factories too (Fig. 4). Total phenol in the urine were colorimetrically determined after the indophenol reaction with Gibbs' reagent in 16 workers usually exposed to benzene, six workers occasionally entering into the workrooms where benzene was used and eight students as the control (Fig. 6). Concentrations of total phenol in the urine of the usually exposed workers had a tendency to be higher in the evening (after work) than in the morning (before work). The concentrations of total phenol in the morning urine of the usually exposed workers were significantly higher than those of the students and had a tendency to be higher than those of the occasionally exposed workers. The concentrations of total phenol in the evening urine of the usually exposed workers were significantly higher than those of the occasionally exposed workers. These results showed that benzene had been actually inhaled by the workers. 3) It was made clear that benzene had been used up to very recent time in over-glaze decoration factories and that the ventilation of the factories were not satisfactory. Benzene is rarely used as a solvent in industries in Japan because it has strictly been restricted by law to use it as a solvent. But benzene had been used exceptionally until recently in over-glaze decoration factories, becaus
Low back pain (LBP) is one of the most common musculoskeletal problems affecting daycare (nursery) workers. We aimed to identify the psychosocial factors influencing LBP in daycare workers.We conducted a prospective cohort study with a one-year observation period. The baseline sample was a convenience sample of 444 daycare workers from 34 daycare facilities in Nagoya, Japan, and its suburbs. All the data were collected through a questionnaire survey. The question "Where are you currently feeling LBP?" was used to determine whether the subjects suffered from LBP. We examined the prospective relationships of the psychosocial work characteristics, i.e., high job strain, low social support, effort-reward imbalance, and overcommitment, at baseline and LBP after one year. We used multiple logistic regression analyses to calculate the odds ratios of psychosocial work characteristics for the persistence and onset of LBP, adjusted for age, sex, body mass index, smoking, employment status, occupation, and working schedule.At baseline, 270 (60.8%) subjects suffered from LBP. Of 208 who also gave information on LBP one year later, 176 (84.6%) suffered from the persistence of LBP. Low social support at baseline was significantly related to persistent LBP one year later. The incidence of persistent LBP was 89.9% and 80.0% among those with and without low social support at baseline, respectively. The adjusted odds ratio (95% confidence interval) of low social support at baseline for the persistence of LBP was 2.43 (1.01-5.87). Of 150 who were without LBP at baseline and provided information on LBP one year later, 45 (30.0%) suffered from the onset of LBP. None of the psychosocial work characteristics showed significant relationships with the onset of LBP one year later.Low social support was related to the persistence, but not to the onset of LBP in a prospective cohort analysis among daycare workers in Japan. High job strain, ERI, or overcommitment did not show a significant prospective effect on LBP.
Abstract A 22-y-old woman was hospitalized for muscle weakness of her lower extremities after she sniffed approximately 6 I of pure toluene during the month prior to admission. The examinations on serum and urine revealed mixed hyperchloremic and high anion gap metabolic acidosis accompanied by impaired urinary acidification. Histopathological changes of the kidney were patchy areas of tubular injury. Acidosis normalized on the fourth day of admission, but both proximal and distal tubular dysfunction persisted. These findings indicate that toluene is a tubular toxin and may contribute to the development of distal renal tubular acidosis.
