To demonstrate delayed neuro-toxicity of organophosphate, we administered 13 types of organophosphorous pesticide to hens. Initially, a screening test was performed with nine varieties of the chemical product. Later, four types were given to the fowls. Those hens dosed with S-Seven and Surecide developed ataxia and other neurophatic symptoms in the lower limbs.
After 50 days of observation, all the hens were killed and anatomized. Phathohistological examination revealed various changes in the hens that developed neuropathic symptoms: atrophy, diminution and disappearance of nerve cells in the anterior horn of the spinal cord ; edematous changes in the myelin; swelling of the neuroglia ; atrophy and vaculolar degeneration of liver cells; and necrobiosis of nepaticlobures.
It was found that these changes are closely related with the development of ataxia and doses of the chemical.
It was also found that the pathotistological changes occurred to a less extent in those hens which did not develop toxicoses.

We investigated the content of NO₃-N in the well water of the eastern, middle and nothern districts of Nagano Prefecture. The NO₃-N content seasonally changes and takes on the pattern of a high in summer and a low in winter.
Rain is considered to dilute the contaminated well water, but it lets NO₃-N flow from the soil into the.well water, when the rain is poured by a typhoon. As a result, a high content of NO₃-N is measured in the well water.
The water sample of 25 out of 85 wells in Matsukawa Town exceeded the tolerance level of NO₃-N (10 ppm, but 44.3 ppm in terms of NO₃^-).
By crop area, the amount of NO₃-N was highest in the fruitgrowing area, which was followed in order of the vegetable-growing area, the flower-growing and the rice planting area.
We consider that the contamination of well water is caused both by chemical fertilizers and the less absorbility of the soil.

Paraquat is one the most popular herbicides in agriculture in Japan. To study the chronic toxicological effects of paraquat on animals, rats were fed a paraquat-containing diet for 1 year and 2 months (1, 5, 25mg/kg of body weight/day). Paraquat administration induced serious histochemical changes in various organs, such as the lung, heart, kidney and liver in rast. Pulmonary fibrosis occurred in the group of rats given 1mg paraquat/kg of body weight/day in diet.
The alkaline phosphatase activity and creatinine content in the blood serum significantly increased. The concentrations of cholesterol, triglyceride and phospholipid in the serum decreased significantly.
A significant increase of lipid peroxidation was observed in the brain, kidney and liver.

Two hundred and thirty adipose tissues were collected from inpatients, who had undergone an operation and an autopsy in the Saku Central Hospital from 1980 to 1982. Organochlorine pesticides were extracted from the adipose tissues and determined by gas-liquid chromatography with an electron-capture detector.
The mean value was 1, 429 ppm for total BHC among males, and 1.665 ppm among females, 4.893 ppm and 3.791 ppm for total DDT, 1.082 ppm and 0.782 ppm for PCB, respectively. Regression analysis between the total BHC residue and the ages of patients indicated a positive correlation for both sexs. As for the relation between the rate of obesity and the residues, low rates of obesity (-10%--19%) were most significantly correlated with high values of total BHC, total DDT and PCB.
We also discussed relations between cancerous diseases and the residues.

Over the past eight years, small doses of an organophosphorous insecticide known in Japan as Sumithion (fenitrothion) have been administered weekly to rehsus monkeys and beagles. In this report, the results obtained during the past three years are discussed.
During the period, two monkeys and one hound died. Pathohistological examination revealed degeneration and disappearance-regeneration of liver tissues, edema of oculomotor muscle stomas, spinal cords and oculomotorius nerve fibers, and atrophy of limph nodes. These are considered the effects of the insecticide.
The surviving animals did not develop any abnormal changes or signs associated with Sumithion-induced disorders. Weight loss was not observed. Routine blood tests were negative. However, serum chemical analyses conducted in the seventh year showed that there are statistically significant differences in GPT, LDH and cholinestrase activity among the animals.

A 70-year-old female with a pulmonary embolism was admitted to a local hospital. On admission, transthoracic echocardiography detected a mobile cardiac tumor on the aortic valve. After medical treatment for a pulmonary embolism, she was slated for a resection of the tumor in our hospital. Although preoperative examinations showed an isolated tumor attached to the non-coronary cusp without valve dysfunction, meticulous intraoperative inspection revealed multiple fine villous tumors located in the left coronary cusp of the aortic valve. Being immersed in saline solution, these tumors had resembled a distinctive sea anemone-like appearance. These fine tumors could not be detected with intraoperative transesophageal echocardiography even in a retrospective manner. We eventually performed aortic valve replacement. The tumors of the two cusps were pathologically diagnosed as papillary fibroelastoma. Of note, a macroscopically undetected tumor was identified in the right coronary cusp by histopathological evaluation. Careful intraoperative observation is essential for surgical decision and patient’s prognosis. It is also considered that latent tumor might be concealed even in seemingly normal adjacent cusps in a case with multiple papillary fibroelastomas.