Objective: The aim of the present study was to determine the prevalence of respiratory symptoms from occupational lung hazards among workers in industries of south Tehran, IRAN. Methodology: This was a cross-sectional study in which by multistage random sampling items on demographic characteristics, cigarette smoking, occupational history and respiratory symptoms were collected of workers. Results: The mean age of the workers was 38.5 (SD = 10.2) yr: age ranged from 19 to 70 yr. Of 880 workers under study, 252 (28.7%) were smoking. Also, it has been observed that workers exposed in the workplace with occupational chemical exposures such as dust, gas and fume pollutants. The prevalence of respiratory symptoms was cough (20.7%), phlegm (41.6%), dyspnea (41.7%), feel tightness (27.4%) and nose irritation (23.5%). Conclusions: Occupational exposures among workers in industries of south Tehran may cause respiratory symptoms and respiratory disorders, engineering controls and industrial hygiene is recommended.
We measured the environmental glutaraldehyde (GA) levels during the disinfection of endoscopes and also investigated the subjective symptoms of the workers engaged in that work. At 6 hospitals in the Tokyo and Kanagawa area, 8 rooms for endoscope washing and disinfecting the endoscopy equipment were surveyed. The geometric mean environmental GA levels in the 8 rooms were 1.3 to 19.6 ppb. The personal exposure levels at the time of replacing the antiseptic solution containing GA in two of the disinfecting rooms were 94.2 and 84.9 ppb. Subjective symptoms such as ophthalmic, nasal, respiratory, pharyngeal symptoms and nausea were more prevalent among workers than controls as evidenced from the questionnaire survey.
Carcinogenicity and chronic toxicity of 1,4-dichloro-2-nitrobenzene (DCNB) were examined by feeding each group of 50 F344 rats and 50 BDF1 mice of both sexes a DCNB-containing diet at a concentration of 0 (control), 320, 800 or 2,000 ppm (w/w) for 2 yr. In rats, incidences of hepatocellular adenomas and carcinomas and their combined incidence were increased in the 2,000 ppm-fed males, together with increased incidence of basophilic cell foci in the 800 and 2,000 ppm-fed males. A dose-related increase in combined incidences of renal cell adenomas and carcinomas was noted. Incidence of Zymbal gland adenomas tended to increase in the 2,000 ppm-fed males. In mice, incidences of hepatocellular adenomas in the 800 and 2,000 ppm-fed females and hepatocellular carcinomas in the 2,000 ppm-fed males and in the 800 and 2,000 ppm-fed females were increased. Incidence of hepatoblastomas was increased in all DCNB-fed males and in the 2,000 ppm-fed females. Signs of chronic toxicity were characterized by centrilobular hypertrophy of hepatocytes with nuclear atypia in mice, increased relative liver weight in rats, a dose-related increase in incidences of chronic progressive nephropathy with advanced grades of severity in male rats, and decreased hemoglobin concentration and hematocrit accompanied by increased bone marrow hematopoiesis in female rats. Carcinogenic activity of DCNB was evaluated for the three different tumors, and sensitive signs of the chronic toxicity were discussed.
The goal of the present study was to investigate the relation of hours of overtime work to cigarette consumption and addiction to cigarette, which was measured by the heaviness of smoking index. The subjects were 571 male daily smokers who responded to a cross-sectional survey of municipal employees of a Japanese city office, in which smoking was permitted in designated areas. Those who engaged in moderate overtime work (10-29 h per month) consumed less number of cigarettes per day and had lower levels of heaviness of smoking index, compared with those who worked either shorter or longer hours of overtime, although the differences were not statistically significant. In the workplace, men who worked 50 h or longer overtime last month consumed, on average, 4 cigarettes more than men who worked less than 30 h of overtime. Home cigarette consumption decreased as hours of overtime work increased. In stratified analysis, there was a significant difference in daily cigarette consumption according to hours of overtime work among smokers in staff position or under low psychological work stress; showing reduced consumption associated with medium levels of overtime work, compared to either no overtime work or extended overtime hours. The U-shaped relations of hours of overtime work to overall cigarette consumption and addiction to smoking deserve further investigations.
Purpose: Maximum oxygen uptake (VO2max) is known to be influenced by life-style factors, such as exercise and smoking. We aimed to further test the hypothesis that, besides these, work form also contributes to increase VO2max among workers. Method: Three thousand six hundred and forty eight male workers with age 38.3 ± 12.1 and 1,575 female workers with age 35.6 ± 11.1, ranging from 20-year old to 69-year old, who participated in Total Health Promotion Plan at workplaces in Fukui Prefecture in 1998 were selected. Data on VO2max were analyzed for age, systolic blood pressure (SBP), body mass index (BMI), work form (sedentary, standing or ambulatory), exercise, and smoking. Results: Multiple regression analysis showed that work form ("standing", "ambulatory"), and exercise habits might increase VO2max while BMI, age, and SBP might decrease VO2max in male participants. Exercise habits were suggested to increase VO2max while BMI, SBP, and age might decrease VO2max in females. In females smoking, was suggested to increase VO2max. Conclusion: After adjusting for age, BMI, SBP, exercise, and smoking, it was suggested that the physical work load, represented by the work form, may contribute to increases in VO2max in males. Implications of smoking among females with respect to VO2max is discussed.
This study investigated associations between lifestyle factors and selected aspects of mental health in a group of Japanese overseas workers and their accompanying spouses who were residing in and around Düsseldorf, Germany, in February 1994. Considering four aspects of mental health (depression, mental instability, nervousness and neurosis) and six lifestyle factors (alcohol consumption, sleeping hours, cigarette smoking, physical exercise, eating breakfast and eating snacks), a cross-sectional study involving 822 volunteers (486 workers and 336 spouses) was performed using the Todai Health Index (THI) for surveying self-perceived health and a lifestyle related self-administered questionnaire. Alcohol consumption had no associations with any of the four aspects of mental health, and only very weak inverse associations were found between the other five lifestyle factors and the four aspects of mental health in the workers group. In the spouses group, physical exercise was the only lifestyle factor significantly associated with mental health.
The present study was initiated to examine the relationship between the workplace concentrations and the estimated highest concentrations in solvent workplaces (SWPs), with special references to enterprise size and types of solvent work. Results of survey conducted in 1010 SWPs in 156 enterprises were taken as a database. Workplace air was sampled at ≥ 5 crosses in each SWP following a grid sampling strategy. An additional air was grab-sampled at the site where the worker's exposure was estimated to be highest (estimated highest concentration or EHC). The samples were analyzed for 47 solvents designated by regulation, and solvent concentrations in each sample were summed up by use of additiveness formula. From the workplace concentrations at ≥ 5 points, geometric mean and geometric standard deviations were calculated as the representative workplace concentration (RWC) and the indicator of variation in workplace concentration (VWC). Comparison between RWC and EHC in the total of 1010 SWPs showed that EHC was 1.2 (in large enterprises with>300 employees) to 1.7 times [in small to medium (SM) enterprises with ≤ 300 employees] greater than RWC. When SWPs were classified into SM enterprises and large enterprises, both RWC and EHC were significantly higher in SM enterprises than in large enterprises. Further comparison by types of solvent work showed that the difference was more marked in printing, surface coating and degreasing/cleaning/wiping SWPs, whereas it was less remarkable in painting SWPs and essentially nil in testing/research laboratories. In conclusion, the present observation as discussed in reference to previous publications suggests that RWC, EHC and the ratio of EHC/WRC varies substantially among different types of solvent work as well as enterprise size, and are typically higher in printing SWPs in SM enterprises.
Forced ovulation induced by the administration of exogenous gonadotropin is a useful marker for studying the ovarian toxicity of chemicals in experimental animals. We examined the toxicity of di-(2-ethylhexyl) phthalate (DEHP) in the ovaries of immature F344 female rats. Superovulation was induced by injections of equine chorionic gonadotropin (eCG) and human chorionic gonadotropin (hCG) in rats dosed with 125, 250, 500, 1,000 or 2,000 mg/kg body weight of DEHP for 4 consecutive days. The number of ova shed during superovulation significantly decreased in rats treated with DEHP at 500 mg/kg as compared with control, but no changes were observed in the number of ova in groups given other doses of DEHP. In control rats treated with olive oil, hypophysectomy reduced significantly the number of ovulated ova. When 2,000 mg DEHP was given to hypophysectomized (hypox) rats, the number of ova in the hypox group was significantly smaller than that in the intact group administered with the same doses of DEHP. In contrast, the numbers of ova of the intact and hypox groups did not significantly differ in rats given 500 mg DEHP. The levels of circulating thyroxine (T4) were significantly decreased by 2,000 mg DEHP in intact rats, and a tendency for T4 to decrease in T4 was also observed in hypox rats given 2,000 mg DEHP. These results suggest that daily administration of 500 mg DEHP suppressed superovulation in immature F344 rats by disrupting the hypothalamic-pituitary-ovarian axis in a manner similar to that of hypophysectomy. Decreased circulating T4 levels seemed to negate this disruption as observed in recovered superovulation after treatment with 2,000 mg DEHP.
This study assessed screening thresholds for determining workers exposure to toluene (Tol) by urinary Tol (Tol-U) and proposed applicable criteria for on-site settings. Participants' urine samples (n = 21) were collected at the end of the workday during the latter half of a week and the Tol-U concentration was assayed. Simultaneously, each worker's exposure dose to Tol in the breathing zone during work, Tol-TWA (time-weighted average), was measured. Tentative criteria were proposed. Level I, less than Tol-U 38 μg/l, has the least chance of exceeding Tol-OEL 50 ppm (occupational exposure limit for Tol recommended by the Japan Society for Occupational Health), probability 95% <. Level II, Tol-U 38-60 μg/l, has a low possibility of exceeding Tol-OEL. Level III, Tol-U 60-110 μg/l, has a high possibility of exceeding Tol-OEL. Level IV, more than Tol-U 110 μg/l, clearly exceeds Tol-OEL, probability 95% <.
Objectives: We conducted this study to examine, whether occupational styrene exposures are associated with reduced hearing ability. Methods: The auditory function was investigated by pure tone audiometry and registration of transitory evoked otoacoustic emissions (TEOAE) in 32 workers of a fibre-reinforced plastic boat building factory. Sixteen subjects were laminators (mean age: 41yr (SD: 8)) and therefore regularly exposed to styrene with mean duration of exposure to styrene of 7.5yr (SD 5.0). The tests were applied to a reference group of 16 workers (mean age: 39yr (SD: 8)) who were not directly exposed to styrene but had a similar noise exposure. Results: A few and isolated correlations between the parameters of hearing acuity and exposure indices, such as current internal styrene exposures (sum of MA and PGA) and duration of styrene exposure, were statistically significant, but no consistent association was found. Conclusion: The results of this study do not support the assumption of an ototoxic effect of chronic styrene exposure in workers.
In this study, a gold amalgam method called the "Double amalgam method" was compared with the ISO 17733 method for mercury vapor analysis method. In terms of sensitivity and ease of operation, the amalgamation method is superior to the oxidation method. Two parallel samplings were carried out in this research at a button battery factory, where the mercury vapor level in the air was about 0.001 mg/m3 and at a fluorescent lamp factory, where the mercury vapor level was about 0.015 mg/m3. In the both cases, the measured values of the two showed good agreement with each other. As these two workplaces represent typical mercury levels in industries today, the double amalgam method is applicable to working environment measurement.
Stress assessment in the workplace has been focused on its environmental, psychological and biological aspects. We carried out an evaluation of the subjective components of stress in a working population of 60 subjects employed in a large Public Service, 30 Video Display Terminal (VDT) workers (15 men and 15 woman) and 30 office-workers not assigned to VDT (15 men and 15 woman), by using the "Rapid Stress Assessment Scale": a short questionnaire of easy administration in work environment. VDT workers of both sexes showed higher total stress score vs. office workers (respectively p<0.05, p<0.05). Gender differences were present: female VDT workers showed higher scores of clusters anxiety (p<0.001) and aggressiveness (p<0.05); male VDT workers' score were significantly higher in somatization (p<0.05) and aggressiveness cluster. Our results showed that in VDT workers are experienced greater subjective response to stress than "office workers" and confirm the gender differences in stress experiencing.
Chronic beryllium disease (CBD) is a rare disease characterized by diffuse interstitial pulmonary granulomatosis. We report a case of CBD which exhibited marked improvement both subjectively and objectively following pulse therapy. The patient was a 36-year-old man whose chief complaint was dyspnea and a dry cough. Since July 1990, the patient had been working in the development of an automatic or mechanical technique for producing beryllium-copper alloy. It appeared likely that the patient may have been exposed to metal beryllium fumes generated from an opening located just above the furnace. The Be concentration exceeded 25 μg/m3 transiently in the breathing zone in this workplace. A chest X-ray film taken in October 1994 showed fine granular shadows throughout the entire lung fields. Around August 1998, the patient's dyspnea became aggravated. An X-ray taken at that time showed linear and reticular shadows, in addition to the diffuse fine granular shadow. In October 1998, after 3 days of methylprednisolone pulse therapy, oral prednisolone 30 mg was initiated. With this treatment, the patient's pulmonary function tests and blood gases improved. Once the patient's condition had improved sufficiently, the dosage of prednisolone was decreased by 2.5 mg every two weeks. The patient continues to be monitored.
Chronic and acute exposure to toxic aerosols belongs to frequent causes of airway diseases. However, asthma attacks due to long-distance inhalative exposure to organic solvents, transmitted via an air condition system, have not been reported so far. The present case illustrates the possibility of air conditioning systems as non-infectious health hazards in occupational medicine. So far, only infectious diseases such as legionella pneumophila pneumonia have commonly been associated to air-conditioning exposures but physicians should be alert to the potential of transmission of toxic volatile substances via air conditioning systems. In view of the events of the 11th of September 2001 with a growing danger of large building terrorism which may even use air conditioning systems to transmit toxins, facility management security staff should be alerted to possible non-infectious toxic health hazards arising from air-conditioning systems.
Several researches has focused the hypothesis that low blood lead levels could be associated with an increased risk of hypertension. To assess the relation between occupational lead exposure and elevated blood pressure a group of 27 workers, age range from 27 to 62 years, mean (SD) 36.52 (± 8.16) yr; length of employment mean (DS) 2.97 (± 1.67) yr, were recruited as study subjects. The following variables were measured: blood lead concentration (BPb), δ-Aminolevulinic Acid Dehydratase (ALAD) activity, Zinc Protoporphirin (ZPP), creatinine, hematocrit, Body Mass Index (BMI) and Systolic Blood Pressure (SBP) and Diastolic Blood (DBP) Pressure. The results showed that long term occupational exposure was related to a slight increase of systolic and diastolic blood pressure among workers who had been exposed to higher level of lead with respect to workers exposed to lower level of lead. Furthermore, blood lead concentration (BPb) and ZPP resulted higher among workers exposed to higher level of ambient lead, while in the same group of workers ALAD activity resulted more inhibited. The authors concluded long term cumulative lead exposure can significantly increase blood pressure in low level Pb exposed workers.
A Car repair painters usually experience long-term exposure to many different solvents. In Italy, the greater part of car painting shops are "handicraft", i.e. 2-5 workers and small premises. Usually workers do not have specific duties, but everyone takes part in all different operations. Moreover, working time is not standardized but varies according to the workload, working methods tend to be traditional, and compliance to individual protection devices is poor. We have hence assessed, on a sample of 8 italian handicraft car painting shops, the exposure levels to solvents, implementing three classic exposure monitoring methods: environmental sampling with charcoal tubes, personal sampling with diffusive charcoal samplers, and urinary determination of unmetabolised solvents. A simple regression analysis was performed to evaluate relationships between the three series of data. The solvents analysed were toluene, ethylbenzene, 1, 2-dichloropropane, n-butylacetate, n-amylacetate, xylene isomers, ethylacetate, and benzene. Benzene was included due to several factors, among others its presence (1% v/v) in the italian unleaded gasoline. Benzene was found in all shops, at levels around or higher than the 8-h time-weighted average limit (8-h TLV-TWA). Other solvents were found in the different shops at various levels, 10-2-10-1 times the 8-h TLV-TWA. Air concentrations of toluene, n-butylacetate, xylenes, and benzene were positively correlated with urinary levels of the parent compounds, while a negative correlation was found for ethylbenzene. The health implications of workers' exposure level was briefly discussed.
We analyzed blood lead (PbB) level from the 2003 health surveillance results of 13,043 lead workers from 1,217 total lead industries to evaluate lead intoxication at low level in Korea. Geometric mean of PbB was 6.08 μg/dl and 56.6% and 7.9% of total lead workers had PbB level over than 5 μg/dl and 25 μg/dl, respectively. Male showed relatively higher PbB level compared to women, but "Manufacture of Other Electronic Valves, Tubes and Electronic Components n.e.c." had more women than male in risk of low level lead exposure. While conventional high-risk industry such as "Manufacture of Accumulators" and "Other Basic Non-ferrous Metal Industries" were remained in high-risk group in lead exposure, there were high risks in other industries such as plastic, chemical and part manufacturing. Non-production tasks such as fork lift truck driving, maintenance, lab testing, and supporting function showed high blood lead level in addition to routine manufacturing processes such as smelting and soldering.