Chlorpyrifos, an organophosphate insecticide, has often been used as a termite-control agent since the advent of regulatory measures against the use of chlordanes in September 1986. A current concern is hazards such as organophosphorus poisoning among termite-control workers. In this study, the blood cholinesterase activity, the number of hours engaged in termite-control work, general conditions, and various test values were examined regularly in eight workers at a termite-control office.
The results are summarized as follows.
1. The plasma cholinesterase level was within the normal range from October 1986 until April 1987 in all workers, but started decreasing after May following the initiation of the full-scale termite-control season. It remained lower than the normal range (0.6 pH) from June until August in five of the six termite-control workers. The lowest level observed during this period was less than 50% of the mean value for each worker prior to the busy season in the six termite-control workers and was less than 10% of the pre-season values in three of them. In two workers, engaged mainly in sales, the plasma cholinesterase activity remained higher than in termit-control workers throughout the season. The lowest level in this minimally-exposed group during this period was not less than 50% of the_mean value for each worker before the busy season. With the arrival of the off season, the level began to recover and returned to normal in all workers in January 1988.
2. The red cell cholinesterase activity remained within the normal range throughout the observation period, but it was generally low during the busy season from June to September and relatively high during the off season from December 1987 to January 1988. On the average, the red cell cholinesterase activity during the season was about 30% lower than that in the off season.
3. No marked subjective or objective abnormalities were seen in the workers. The results of other tests were generally normal, although a slight decrease in the red cell and white cell counts as well as abnormalities in serum lipid and lipase were noted in some workers. Further observations are necessary.
4. A significant negative correlation was noted between the number of hours engaged in termite-control work and variations in the plasma cholinesterase activity. During the season, the plasma cholinesterase activity (lower than the normal level) was maintained when the number of working hours per day was 2 to 2.5, decreasing with continuous days with a greater number of working hours and increasing with continuous days with a smaller number of working hours.
5. It is suggested that plasma cholinesterase activity is a very sensitive indicator for exposure to chlorpyrifos, and that it may be used effectively to monitor exposure levels and health in termite-control workers.

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A follow-up study was carried out from January 1967 to December 1986 on 148 patients with Itai-itai disease, 130 suspected patients (persons requiring observation), and 212 controls who were living in the same community as patients with Itai-itai disease. The relative survival rates for the three groups were calculated from a life expectancy table. Except for 1973 data, comparison of the annual data from 1968 to 1986 showed that the relative survival rates in the patient group were significantly lower than those in the control group. The relative survival rates in the suspected patient group were significantly lower than those in the control group between 1981 and 1986. Recently the differences of the relative survival rates between the patient group and the suspected patient group have become smaller and are not significant. These results show the long-lasting influence of Itai-itai disease on the prognoses of patients and suspected patients.

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[in Japanese]

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The right to clean air in public places (RCA) could be a good indicator of health consciousness. We surveyed the consciousness of RCA among residents (20 years of age or older; n=1500) in city D, a satellite town of Osaka, and examined the relationship between life style and the knowledge aspect of RCA, one of the three aspects of the consciousness concerning RCA.
Knowledge of laws concerning the smoking regulations in public places are divided into two categories. One is knowledge of laws concerning general matters, and the other is knowledge of laws concerning concrete matters. Therefore, we get two kinds of relationships. These are the relationship between life style and knowledge of laws concerning general matters, and the relationship between life style and knowledge of laws concerning concrete matters.
We examined these two relationships by using Student's t test, and tried to determine the individual life style closely related to the scores for knowledge of laws with the chi-square test. We got following results.
(1) The relationship between life style and knowledge of laws concerning general matters
Knowledge scores got higher as the life style scores (HPI) became higher. This trend could be detected in all four subgroups. The scores of male subgroups were generally higher than those of female subgroups. This could be construed as follows: those who take care of their physical health have a lot of knowledge of laws concerning smoking regulations.
(2) The relationship between life style and knowledge of laws concerning concrete matters
Knowledge scores got lower as the life style scores became higher. This trend was almost the same in all four subgroups. The scores of male groups were generally higher than those of female subgroups. This trend could be construed as follows: men and women whose HPI is lower get more opportunities to be in the public places where smoking is totally allowed (e. g., bars) irrespective of their smoking status.

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An epidemiological survey on serum lipids and apolipoproteins in school children in Goshiki-cho, Awaji-Island was carried out from 1985 to 1988 and their relations to blood pressure, anthropometric values, nutritional intake and a family history of hypertension were investigated. Parent-child and sibling-sibling correlations of the values were also analyzed. The results obtained were as follows:
1. During a 3-year follow-up from 11 to 14 years of age, serum levels of apo AI, apo AII, apo B and LDL cholesterol decreased at 12 years of age in both males and females. A tracking phenomenon was observed in serum levels of lipids and apolipoproteins.
2. Males at 10-14 years of age with a family history of hypertension (FH+) showed significantly higher systolic blood pressure and erythrocyte Na/K ratios than those without such a family history (FH-). The FH+ group (both males and females) had lower serum HDL cholesterol and higher levels of apo B, LDL cholesterol and triglyceride.
3. Significantly positive correlations were observed between apo AI levels of mother-son pairs and between those of elder and younger brother pairs. A positive correlation was observed between apo B levels of elder brother-younger sister pairs. Serum levels of total, HDL and LDL cholesterol in school children were closely correlated with the levels of the respective cholesterols in parents. Similar correlations were observed between sibling-sibling pairs.

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Six-week-old male Wistar rats were administrated the radioisotopes of five trace elements (iron, zinc, copper, manganese and iodine) intravenously in order to elucidate the significance of their pharmacokinetics by noncompartmental analysis.
The mean residence time (MRT) and variance of residence time (VRT) increased in the order Mn, Cu, I, Fe and Zn. Neither MRT nor VRT indicated any statistical significance between I and Fe. These results suggested that Mn and Cu were voided rapidly from the plasma, whereas Zn persisted in the plasma for the longest time among these elements. Though I and Fe showed quite different plasma disappearance curves, both were considered to diminish at almost the same speed.
The volume of distribution at steady state (Vdss) increased in the order Cu (32ml), Fe (62ml), I (149ml), Mn (185ml) and Zn (1012ml). The distribution coefficient (Kd) of these elements increased in the same order as Vdss did. For Cu and Fe, Vdss was intermediate between the plasma volume and total body fluid volume of the rat, while, for the others, Vdss was greater than the total body fluid volume. In particular, Vdss of Zn was the greatest among these elements. Hence, the present study suggested that the plasma concentrations of Cu and Fe may reflect their body contents fairy well though those of I, Fe and Zn can hardly do so. Vdss and Kd are, therefore, considered to be useful as supplementary diagnostic indices to understand the plasma concentrations of trace elements.
Systemic clearance (CLs) increased in the order Fe (0.02ml/min), Zn (0.07ml/min), I (0.21ml/min), Cu (0.37ml/min) and Mn (4.61ml/min). The CLs of Mn was similar to the hepatic plasma flow rate of the rat in size, indicating that the Cls of Mn may be one of the greatest among trace elements. It appeared, therefore, that when administered intravenously, Mn may be transfered from the plasma to the tissues more easily than the other elements.

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HL-60 cells were derived from a patient with myelocytic leukemia, and are known to be in the promyelocytic stage and to differentiate into myelocytes or granulocytes after induction with several materials, e. g., DMSO, retinoic acid, and interferons.
The authors intended in this report to determine whether asbestos fibers have any effect on the differentiation processes of HL-60 cells induced with DMSO. The cells were induced to differentiate by incubation with 1.25% DMSO for 4 days. A decrease in the percentage of c-myc-protein-positive cells and an increase in the number of C3bi receptor (CD11b) positive cells were observed after differentiation. When crocidolite (50μg/ml) was added to the culture dishes at the beginning of the experiments, the differentiation was inhibited. An increase in the percentage of c-myc-protein-positive cells and a decrease in that of C3bi-receptor-positive cells were observed compared with the cells induced with DMSO alone.
It has been reported that DMSO activates phospholipid- and Ca²⁺-dependent protein kinase and induces the differentiation of HL-60 cells. The mechanisms of inhibition by crocidolite fibers of the effects of DMSO remain to be clarified, but the strength of activation of phospholipid- and Ca²⁺-dependent protein kinase may play an important role in the following induction of cell differentiation.

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The trend of divorces has been usually evaluated by the divorce rate. However, it is difficult to make detailed analyses of the trend of or relevant factors concerning divorces by the divorce rate, because the denominator of this index is not a population at risk of divorces.
The application of the life-table method to calculation of cumulative incidence rate of divorces for a birth cohort based on vital statistics data was introduced and its problems were discussed. This method was able to give a precise incidence rate of divorces and made it possible to examine the relationship of marital durations, generation of cohorts or age at marriage to the incidence of divorces. The results obtained were as follows:
1. The cumulative incidence rate of divorces increased and the marital duration-specific incidence rate of divorces decreased with continuation of marriages.
2. The cumulative incidence rate of divorces was higher in younger birth cohorts than in older cohorts.
3. The cumulative incidence rate of divorces was the lowest in the cohort married when the husband was 23 to 32 years of age than in the cohorts with other ages at marriage in all the birth cohorts examined.

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The purpose of this study was to examine the effect of umpires' intake of water during a summertime baseball game, on serum and urinary biochemistological elements, body weight and physiological factors.
Twenty-eight umpires were classified into two groups. Group W was composed of 14 umpires who had water white those who did not were group C. Group W had 250ml of water that was cooled to about 5°C after the 5th inning of the game.
The game was played in the following environment: atmosphere temperature was 31°C; wet-bulb temperature was 26°C; blackglove temperature was 40°C; the velocity of the wind was 1.18m/sec in bright sunshine on a hot and moist day.
The results obtained were as follows. In group W, more body weight was lost than in group C, but statistically there was no significant difference. Urinary volume in group W became smaller than in group C, but statistically there was no significant difference. Water in blood increased in group W and decreased in group C but statistically there was significant difference. In both groups, oral temperature decreased, but only in group C was there a statistically significant difference. Although the intake of water increased the volume of perspiration, it did not dilute the concentrated blood, suppress the rise of body temperature, or result in a rise of low blood pressure.

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Optical character readers (OCR) were introduced into an office as input devices for a computer system. In order to input data in to the system, workers of this office had to write down the data on sheets of specially formatted paper, called OCR cards. Some workers engaged in this task complained of symptoms of occupational cervicobrachial disorders (OCD). Observation suggested that the constrained motion of writing on OCR cards may cause such symptoms. Therefore, in order to prevent OCD, the writing motion was analyzed. The electromyogram of the upper extremities and shoulders was also compared between normal handwriting and constrained writing on the OCR cards in laboratory studies.
The results were as follows.
1. Writing time per letter for the OCR cards was longer than that for normal handwriting.
2. Discharge of muscles observed through electromyogram was larger per letter for the OCR cards than for the normal handwriting.
3. Discharge from the trapezius per unit time for the OCR cards was rather large. This phenomenon showed that the workload of constrained writing was heavier than that of normal handwriting.
The results suggests that more careful preventive measures for OCD should be promoted in comparison with ordinary clerical tasks.

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