physiological criteria of seaman in hot enviroment on J506 ship during the voyage on the tropics was investigated in May, 1980. It was found that the 6 physiological heat criteria(body temperature, pulse rate, electrocardiogram, 3 hours-sweat, urinary salt and the quantity of 24 hours-urine)were within the tolerable limits at the ordinary works, and the cabin temperature was not more than 32℃ (WBGT).The body temperature and pulse rate elevated when the workload increased.When the ship transfer from the high latitudes to the low latitudes in a short time,it is advised to a heat acclimatization, otherwise, the heat damags even heat stroke would occur.The water and electrolytes of the seaman was maintained in balance on the voyage. No special supplement was needed.

The toxic effect of boron on Langerhans' islands was studied with insulin radio-immunoassay.The results were as follows : the blood sugar decreased and the level of blood insulin increased in the experimental group (taking boron 30mg/kg body weight per day for 96 days),compared to those in the control group,and a deviating phenomenon of excretion curves occurred.The results suggest that boron may have a toxic effect on ?-cells of Langerhans islands,which leads to an increase in blood insulin and a decrease in blood sugar,and Langerhans' islands may be relatively sensitive target organs.This study will be of some value in making the criterion of boron concentration in drinking water for short term consumption of troops in war.