The red blood cell (RBC) glutathione peroxidase (GSHPx) activity and selenium (Se) concentration were measured in healthy Japanese pregnant women and in non-pregnant controls. The GSHPx activities in RBC of full-term pregnant women were significantly higher than in non-pregnant women (p<0.01).
The Se concentrations in RBC of full-term pregnant women were significantly higher than in non-pregnant controls (p<0.05).
In the whole blood of full-term pregnant women a positive correlation was found between Se concentration and hemoglobin content (p<0.05).
The Se concentrations in RBC of cord blood were significantly higher than in non-pregnant controls (p<0.01).
The GSHPx activities in RBC of cord blood were significantly lower than in non-pregnant controls (p<0.01).

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Exposure of primary school children and their mothers to No₂ was investigated in two schools in the city of Sapporo. One school was located in the city center and another in a suburb of the city. The school children and mothers were requested to put on NO₂ filter badges for 24 hours and to record activity during that period. They were also requested to fill out ATS-DLD questionnaires. The surveys were repeated twice, in the summer of 1986 and in the winter 1987, due to possible seasonal variation.
Average NO₂ exposure levels of both school children and mothers were lower in the summer than the corresponding averages in the winter. The average of the children was lower than that of mothers in both summer and winter. Averages of the children of the city-center school were higher than those of children in the school in the suburb in both summer and winter. These differences were not observed in mothers' averages. To examine the relationship between NO₂ exposure levels and maternal daily behavior and habits, the subjects were classified into three clusters by employment status, living area, smoking habits, type of heating appliance, and use of fans during cooking. While average NO₂ exposure levels of children were similar among the three clusters, the average of the mothers of the third cluster was the highest among the clusters in either summer or winter. The third cluster was characterized by the highest rate of employment among the clusters, spending less time in their kitchens and not using fans regularly.
These observations indicated that factors associated with NO₂ exposure were different between children and mothers and that mothers engaged in occupations were at higher risk of NO₂ exposure.

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Soybeans and soybean products are common foods customarily eaten by the Japanese people. They significantly contribute to the Japanese diet as vegetable protein sources. The digestibility and energy availability of kori-dofu (dried bean curd), however, have not measured in previous studies, whereas those of soybeans were determinated based on studies in Western people¹⁾. Therefor, it is important to established these data for Japanese subjects. There have been few studies in this field in Japan^2-4) and only a few reports have clarified the energy availability of pulses. In the present study, we measured the digestibility and energy availabilities of soybeans and kori-dofu, which make up an important part of the Japanese diet.

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Eight hundred and twelve vital statistics death certificates, in which either the cause of death or complications was SMON, were selected from all the death certificates filed in Japan in a 13-year 6-month period from July 1972 to December 1985.
In 411, or 50.6%, of these certificates, the SMON Research Committee had records of the clinical pictures as a result of the nationwide surveys conducted earlier. The epidemiological picture presented by the death certificates and the relationship between the information in these certificates and clinical records in nationwide surveys was observed. The results are summarized as follows:
1. The male/female ratio revealed in the 812 death certificates was 0.53, which is higher than those reported in nationwide surveys (0.4).
2. Although the yearly number of certificates was more than 70 in 1974 or before, it decreased year by year. The numbers in 1984 and 1985 were less than 50.
3. The leading underlying causes of death were; SMON in 44.0% of all the certificates, heart diseases in 10.3%, cerebrovascular diseases in 9.2% and malignant neoplasm in 8.6%.
4. The presence of clinical symptoms was compared between death cases and total cases reported by the nationwide surveys. Symptoms such as visual impairment and walking incapacity were seen more frequently in death cases.
5. From these results, it was suggested that the level of the severity of the disease at onset influences the long-term prognosis of the disease, although selection bias in the death certificates observed is unavoidable.

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The relationships among high-density lipoprotein cholesterol (HDL-C) and other serum lipid items, and active smoking, passive smoking, obesity, alchohol drinking and working status were investigated.
This study was performed both in healthy adults and in schoolchildren. The adult group was sampled at random from those who were diagnosed to be healthy by medical examination at the Automated Multiphasic Health Testing and Services Center in Tokai University Hospital, and the schoolchildren group was selected with regular health examinations in a primary school in Tokyo. In the case of adults, it was found that the greater the value of triglyceride (TG), the greater the number of cigarettes smoked. On the other hand, HDL-C decreased with increasing cigarette smoking. Obesity level increased with increasing values of TG, total cholesterol (TC) and low density lipoprotein (LDL-C) but in the case of HDL-C, the value decreased. Alchohol drinking made the HDL-C level increase.
Although the HDL-C level increased slightly with obesity, the relationship between HDL-C and passive smoking was not clear in the case of schoolchildren.

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The ability of methylmercury (MMC) to induce lipid peroxidation was tested in rats.
One group of 5 rats (MMC group) took a diet to which 10 ppm of methylmercury was added while another group of 5 rats was fed a diet containing no MMC as a control. During the experimental period of 14 weeks (98 days) on these diets, body weight gain and amount of food consumption were checked individually for each two-day interval. Samples of expired air and blood were obtained every two weeks and analysed for ethane and pentane production and for plasma fatty acid composition, respectively. Results obtained were as follows:
1. During the first half of the 14-week experimental period, there was no significant difference in the amount of food consumption between the MMC group and the control group. However, a significantly smaller amount of food consumption was found in the MMC group as compared to the control group during the latter half of the experiment. The amount of food consumption was directly reflected in the body weight gain throughout the experimental period.
2. The amount of expired ethane was generally higher in the MMC group than in the control group throughout the experimental period. During the last 2 weeks of the experimental period, the difference in the amount of expired ethane between the two groups was statistically significant.
3. The amount of expired pentane was also higher in the MMC group than in the control group during all the weeks of the experimental period. Significant differences in the amount of expired pentane between the MMC group and the control group were found during the second, eighth and tenth weeks of the experimental period.
4. The fatty acid composition in plasma was affected by the amount of food consumption per se in that the concentrations of saturated and monoenic acids were generally lower in the MMC group than in the control group throughout the experimental period. During the last 2 weeks of the experimental period, however, the concentration of polyunsaturated fatty acids in the MMC group was increased in spite of the decreased amount of food consumption. The value of 20: 4/18: 2 in plasma was also higher in the MMC group than in the control group during all weeks, particularly during the latter half of the experimental period.
5. From the above-mentioned results, the possible induction of lipid peroxidation by low dosage levels of methylmercury for a long time was discussed in relation to the mechanism by which the development of neurological disturbance in MMC poisoning might occur.

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Statistics have shown that approximately 50% of those expiring from sudden cardiac death (SCD) are found to have a coronary artery disease with extensive atherosclerosis and myocardial damage, although this is usually discovered on autopsy since SCD often occurs with no prior overt sign1-5). Therefore, the identification of the precipitating mechanisms that bring on SCD is hampered, for intensive medical observation of the victim during the critical moments prior to its onset is rarely possible.
Though SCD is a frequent cause of death, it remains diffcult to study. It is impossible to predict in whom it will occur, since SCD strikes without warning and, more often than not, in an out-of-hospital setting. Under such circumstances, retrieval of the victim's physiological data is often impossible.
When SCD has occurred within a hospital setting, study of the Holter monitoring records has demonstrated that ventricular tachycardia degenerating to ventricular fibrillation is one of the final events leading to SCD6-9). It must be noted, however, that Holter monitoring requires a minimum of 24 hours and, further, at least 30 minutes to analyze the recorded data.
For these reasons, Holter monitoring is not suitable for checking the health of the population at large to uncover those likely to incur SCD, when compared to the conventional methods presently used, such as ECG, chest x-rays, and blood sampling. Thus, the present study is to investigate whether the conventional methods have some value in predicting the occurence of SCD. An attempt is also made to clarify the pathology of SCD, since it is rather obscure.

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To determine whether lithium deficiency has an effect on lever-press avoidance behavior, low lithium diets were given to mice and the effects of these diets on conditioned lever press avoidance response were compared with that of a commercial diet containing 110ng Li/g diet. Three low-lithium diets were prepared in this experiment and the lithium contents of the diets were 6.6, 36.6 and 76.6ng Li/g diet. The mice used in this experiment had been maintained on a practical diet and trained by Sidman's situation previously. After checking that the conditioned response was established, they were divided into four groups. Three groups of mice each were given one of the low lithium diets, indicated above, and these were assigned into the lithium-deficient groups. Some mice were given the practical diet and this group was used as controls. The avoidance behavior was analyzed by the method reported previously by the authors.
After changing the diet to a low-lithium one, the avoidance behavior was significantly suppressed in lithium-deficient groups and this appeared to be proportional to the level of lithium deficiency in the diet. Furthermore, this suppression in the avoidance behavior was recovered by lithium supplementation in the same experimental diet.
These findings suggest that low-lithium intake may suppress acquired avoidance behavior in mice.

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Regarding airborne bacterial flora floating in outdoor air, Gregory1) has presented the following composition; 66% Micrococcus, 25% Bacillus, 6% Bacterium and 1 to 2% Vibrio. Wright et al.2) investigated the vertical distribution of airborne bacteria to 500 ft above the ground in the twin cities area and observed that bacterial flora at an altitude of 35 ft was composed of 28% Gram-positive asporogenic rods, 25% Gram-positive sporogenic rods, 17% Gram-positive cocci and Gram-negative rods and 14% diphtheroids. In the atmospheric layer ascending to 500 ft, the five groups of airborne bacteria decreased to about 1/3 to 1/5 of the amounts found at 35 ft. Mancinelli and Shulls3) investigated the airborne bacterial composition 10m above the ground in an urban environment where eleven genera of cocci, which were composed of 41% Micrococcus, 11% Staphylococcus and 8% Aerococcus, and seven genera of rods were recognized.
On the other hand, dynamic aspects of airborne bacteria have been also investigated with special reference to taxonomical and physiological characteristics of indicator strains. In 1946, Zo Bell4) reported that inland from a sea wall to a distance of 1600m, airborne bacteria occurring from the ocean could be estimated by a bacterial ratio developed on sea-water agar and fresh-water agar. Concerning the movement of bacteria by air current, Bovallius et al.5) investigated the migration of colored airborne particles together with a few adherent kinds of Bacillus in a sandstorm area from the Black Sea to Sweden. Recently, Fukaya et al.6) investigated the spread of airborne human enteric bacteria in an area around a sewage treatment plant established in the city of Nagoya. Distribution ratios of Enterobacteriaceae were 66% of the bacterial flora at the plant site and about 60% in the surrounding area. Taxonomical investigation of collected airborne bacteria revealed the presence of Enterobacteriacea such as Enterobacter agglomerans, Serratia rubidaea and Citrobacter freundii.
Our study was intended to elucidate some dynamic aspects of airborne bacterial flora over a wide area. Investigation was carried out by a filtration method using a soluble gelatin foam filter and continued for a year in an experimental area of the campus of the University of Occupational and Environmental Health (UOEH).
Airborne bacteria near the ground at station P were mainly composed of Gram-positive cocci and Gram-positive rods, but the bacterial compositions observed at each experiment that was repeated varied considerably in their ratios. The dispersion profile of bacterial flora over the experimental area, which was surveyed from observed results at stations A to E and P, indicated the existence of different floras corresponding to geographical features in areas around the observation stations. Airborne staphylococci collected at stations P and E were further investigated for the distribution of strains resistant to antibacterial reagents.

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In pest control operations, organophosphorus compounds (OP) have been sprayed as insecticides. Blood cholinesterase (ChE) activities and urinary alkylphosphate levels were measured for both OPsprayers (n=102) and non-sprayers (n=35) in pest control companies, and the relationship between the analytical results and spraying conditions was investigated.
Plasma ChE activities of the OP-sprayers and of the non-sprayers, as well as blood cell ChE activities of the OP-sprayers, were significantly lower than those of employees of chemical factories who served as controls (n=103). Urinary alkylphosphates were not detected in the controls at all but were detected in 83% of the sprayers and in 57% of the non-sprayer employees of pest control companies.
A significant negative correlation (r=-0.34, n=137, p<0.01) between the plasma ChE activities and urinary total alkylphosphate levels was observed in employees of pest control companies. In the case of the employees whose urinary total alkylphosphate levels were 0.1μmol/g creatinine or more, the plasma ChE activities were 25% decreased compared to the control group.
The OP-sprayers showed significantly higher urinary total alkylphosphate levels than the nonsprayers. The OP-sprayers were further divided into two groups. One was sprayers engaged in both cockroach- or fly-control and termite-control operations (sprayers I, n=54) and the other was sprayers engaged in only cockroach- or fly-control operations (sprayer II, n=48). The sprayers I group showed higher urinary diethylphosphate and diethylthiophosphate levels than the sprayers II group, and, inversely, the sprayers II group showed higher urinary dimethylphosphate and dimethylthiophosphate level than the sprayers I group. However, a difference was not observed between the total alkylphosphate levels of sprayer groups I and II.
The levels of urinary alkylphosphates of the OP-sprayers were decreased with the number of days after the last spraying; the workers who sprayed 4 days or more before showed the same urinary levels as the non-sprayers. The passage of time did not affected not only blood cells but also plasma ChE activities.
These results indicate that levels of urinary alkylphosphates reflect recent OP-spraying qualitatively and quantitatively and that urinary alkylphosphate levels are useful as an index of exposure to OP.

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