The question whether occupational exposure of parents to chemicals, electromagnetism and radiation causes malignant disease in their offspring has gained much interest. The findings to date, however, have been conflicting perhaps due to differences in the methods employed in these studies. A review was made on 16 case-control epidemiological studies. In 11 studies significant relation was observed between malignant tumor (leukemia, braintumor and others) and occupational exposure to hydrocarbons, spray paint or other chemicals, ionizing radiation and electromagnetism. Conversely, no association was observed in five studies, in which different populations, different techniques, and different control groups were employed. The purpose of this paper is to examine the role of occupational exposure of the parents to chemicals and other agents to the devedopment of malignant tumors in their off spring in relation to the employed epidemiological methodology.

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Effects of inhalation of several organic solvents on left ventricular contractility were investigated by using left ventricular dp/dt in anesthetized dogs. The first derivative of the left ventricular pressure was obtained by an electronic differentiating circuit and recorded continuously. As orgamic solvents, 1, 1, 1-trichloroethane (1, 1, 1-TCE), trichloroethylene, tetrachloroethylene, toluene, m-xylene and trichloro-trifluoroethane (FC-113) were used in this study. Each solvent was separately inhaled for a period of approximately 2 min.
In the acute inhalation experiments, peak dp/dt that was the maximal left ventricular dp/dt decreased following inhalation of each organic solvent. The threshold concentration of 1, 1, 1-TCE, trichloroethylene, tetrachloroethylene, toluene, m-xylene and FC-113 required to decrease peak dp/dt was approximately 0.2%, 0.15%, 0.2%, 0.38%, 0.35% and 0.35%, respectively. These results indicated that the decrease in peak dp/dt was induced following inhalation of each solvent, but threshold concentration of the solvents to produce decrease in peak dp/dt was different. Inhalation of organic solvents of higher concentrations markedly decreased peak dp/dt. A dose response relationship was observed between decrease in peak dp/dt and concentration of the solvent greater than the threshold level. The degree of decrease in peak dp/dt following inhalation differed by kind of solvents with the greatest decrease in peak dp/dt being induced by tetrachloroethylene inhalation.

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Chlorpyrifos (O, O-diethyl-3, 5, 6-trichloro-2-pyridinyl phosphorothioate; CP) has been used for insecticide to prevent infestation of termites. A study was made on occupational exposure to CP of termite control workers engaged in spraying this organophosphorus insecticide.
Workers were engaged in two types of spraying; that is spraying CP under floor and spraying CP around house. All the under-floor sprayers wore respirators during spraying. CP levels in air near the breathing zone, contact amounts of CP with skin, and urinary alkylphosphates levels were higher in the under-floor sprayers than in the around-house sprayers. The personal ambient CP levels of the under-floor sprayers were 0.012 to 0.145 (8 h-TWA, mg/m³) lower than the threshold limit value (0.2 mg/m³) proposed by ACGIH.
A maximum diethylphosphate (DEP) excretion was observed in the first urine collected the next day, while the highest diethylthiophosphate (DETP) was excreted in the last urine in the working day. In the excretion amount, DEP was higher than DETP.
Amounts of CP collected in respirators used by the under-floor spraymen averaged 0.76 mg/respirator comparable to their estimated theoretical value of 0.69 mg/m³. The urinary total alkylphosphate (DEP+DETP) level was more closely correlated with the contact amount of CP with skin (γ=0.86) than with the personal ambient CP level (γ=0.05).
These results indicate that 1) respiratory absorption of CP was prevented by the use of respirator; 2) the urinary alkylphosphates were mainly derived from the dermal absorption of CP; and 3) biological monitoring using urinary alkylphosphates levels is an useful index for CP exposure.

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Determination of tributyltin and its metabolites, dibutyltin and monobutyltin, in biological materials was made by capillary gas chromatography (C-GC) using a flame photometric detector (FPD). Butyltin compounds (BuTC) were extracted (as bromides) from tissue homogenates with hydrobromic acid and ethyl acetate. These compounds were converted to pentyl derivatives with pentyl Grignard reagent and then analysed by C-GC. The recoveries of each BuTC added to tissues were 96-99% for monobutyltin, 87-93% for dibutyltin and 90-93% for tributyltin. The detection limit of BuTC was 4-5 pg as tin. This method was applied to the analysis of BuTC in the liver and kidney of rats orally administered tributyltin chloride. Time course of three BuTC showed that the maximum value appeared 24 h after administration of the tin compound, which was followed by a rapid decrease. The order of the concentration of BuTC in both organs was dibutyltin>tributyltin>monobutyltin. The rate of dealkylation was more rapid in liver than in kidney.

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A questionnaire survey was conducted on 5, 523 taxi drivers in Osaka Prefecture to investigate their working conditions and daily life as well as characteristics of their health condition and various effects on health, especially on their cardiovasuclar system.
The major results of this survey were as follows:
1) The rate of subjective symptoms, morbidity rate and rate of poor physical condition over the past year in the taxi drivers were higher than those of the control group. Among the subjective symptoms, the rate of gastrointestinal disorders, fatigue, musculo skeletal system disorders, sensory system disorders, hemorrhoids, etc. was especially high.
2) Work shift, density of work, years of experience in taxidriving, frequency of fright while driving, pattern of taking meals, way of recuperation on rest days or holidays, obesity, smoking, and intake of coffee and alcohol were found to be factors affecting the health of taxi drivers.
3) Nearly half of the respondents said that they would like to quit or change their job with as much as 62% giving “condition of health” as reason. On the other hand, the rate of heartrelated symptoms such as palpitation, and breathlessness did not differ from that of the control group. The possible reason for this deduced from the foregoing results, is that there were some who had changed or quit the job at an early stage for health reasons snch as heart trouble and severe physical and mental burden resulting from taxi driving.
4) Many taxi driver are obese and the rate of those with heartrelated symptoms was considerably high among those classified as obese. In addition, the results showed that those with longer driving experience tended to be obese.

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