With automated nitrogen oxides analyzers, it is stipulated that “Nitrogen gas of high purity (in a cylinder) is used as the zero gas for zero drift measurement.” This study made use of the fact that peroxides of alkaline earth metals purify ambient air containing nitrogen oxides by absorption. It was thus established that this purification method consisted simply of passing the air through a layer of absorbent makes possible preparation of zero gas for use in zero drift measurement.

View full abstract

The heavy-metal contamination in the air is generally of low concentrations in the ordinary living circumstances. However, its chronic effect on man can not be ignored since the intake of such metals is an inevitable and continuous process throughout our life span. Therefore, it seems to be significant to know how much metals are inhaled and deposited in the lung of ordinarily living people.
The lungs of 180 administrative and juridical autopsy cases which were carried out in Kanagawa Prefecture during the past one year were investigated to measure the metal contents. They were classified and analyzed acccording to diffents ages residential area, and occupations.
The results were as follows:
1. Cadmium: The lungs of teenagers and twenties contained a significantly higher amount of cadmium than that of those under 10 years of age, which gradually increased with age afterwards.
Lead: Teenagers had a significantly higher amount of lead content in their lungs than that of those under 10 years. However, no more significant increase was noted over 21 years of age.
Copper and nickel: No significant differences in ages were not observed.
2. Significant differences in amount between different areas, industrialized area, partly industrialized area and an ordinary residential area, were observed in content of cadmium in the lung but not in other metal contents.
3. Some significant differences attributable to the difference in occupations were seen only in the cadmium content in the lung.

View full abstract

Pulmonary function, measured by means of flow-volume curve method, of the 130 healthy students of Kansai Junior High School (K-school) which was located in the area designated by the Pollution-related Health Damage Compensation Law was compared to that of the 513 healthy students of Terao Junior High School (T-school) which was located outside of that area for three successive years. Both schools were located in Tsurumi Ward of Yokohama City.
The following results were obtained:
1. On the maximal expiratory flow of V75, PFR, V75/Ht, and PFR/Ht, which are reflecting the states of central airways, those in T-school tended to have higher values than those in K-school for 3 years respectively.
2. On the values of V50, V25, V50/Ht and V25/Ht which are reflecting the states of peripheral small air ways, K-school were higher than T-school at 12-year-old group in the first year and at the all groups in the second year. But the values in T-school were conversely higher than in K-school at the all groups in the third year.
3. The frequency of subjects, who had shown high value of V50/V25 which is one of the indices to detect obstructive lung disorder, increased higher as the students grew older. The tendency was more remarkable in K-school than in T-school, but there was no significant difference.

View full abstract

Metabolic pathway of inhaled NO was investigated with ¹⁵NO in rats.
After the ¹⁵NO exposure with exposure apparatus shown in Fig. 1, contents of the ¹⁵N (atom % excess) in blood, red cell, serum, each organ tissue (perfused with saline solution) and urine were estimated. Contents of the ¹⁵N in the samples of blood, serum, red cell and urine were relatively high and those of lung, trachea, liver, kidney and muscle were low (Table 2 and Fig. 2).
Blood samples in an hour after ¹⁵NO combined blood injection from rats were analyzed. Greater part of the ¹⁵N in the serum were in fraction of the ultrafiltrate and contents of NO^-₃ in the serum werer emarkably elevated compared with those of the control rats (Table 4).
In 24 hours and 48 hours after ¹⁵NO combined blood injection, the urine samples were collected. Most of the ¹⁵N in the urine was found within 24 hours (Table 5).
Red cells from the ¹⁵NO exposed rats were washed (mixrd and incubated) with the saline solution or serum from normal untreated rats. The 15N in the red cells was easily extracted with the solution or the serum, but the 15N in serum from the exposed animal was scarcely transfered to red cells (Table 3).
Through the experiments, we presumed that inhaled NO primarily reacted with hemoglobin and was changed to NO^-₂/NO^-₃ in red cells, then the metabolites were removed to serum and a part of those reacted with tissues and the other greater part was excreted in urine in the form of NO^-₃ (Fig. 4).

View full abstract

Poly butyl methacryate (PBM) is used as a material for transfer papers in overglaze decoration of ceramic industry. In the process of ceramic burning some irritative odors are generated, and it seems to be caused by burning of transfer papers.
For the purpose to study the above, some carbonyl compounds generated by thermal decomposition of PBM were examined on the products, the generating tendency and the generating amounts.
1) The following were identified as the products of thermal decomposition; formaldehyde, acetaldehyde, propionaldehyde, n-butyraldehyde, acrolein and acetone.
2) The following tendency of generation was recognized; aldehydes (formaldehyde, acetaldehyde and n-butyraldehyde) begin to be generated about 100°C and the generating peak of aldehydes is about 265°C.
3) The order of the generating amounts among aldehydes was as follows; acetaldehyde was the greatest, followed by formaldehyde and n-butyraldehyde.
4) The following was recognized about the irritative odors generated in the burning process of overglaze decoration, they are caused by some carbonyl compounds, generated by thermal decomposition of PBM.

View full abstract

The application of the inductively coupled plasma (ICP) to an emission source for the spectrometric determination of trace elements (Be, Zn, Pb, Cd, Ni, Mn, Fe, Cr, V and Cu) in air borne particulate matter is presented. Samples of airborne particulate matter were collected on various sizes of glass fiber filters (Toyo GB-100R) by means of a conventional high volume air sampler and a low volume air sampler installed a cyclone for preliminary separation of larger particles than 10μm in diameter. A size selective sampler was also employed to collect airborne particulate matter in two separate aerodynamic size ranges; coarse particles (>2μm) and fine particles (<2μm). The sample preparation, the sensitivity and the precision were discussed in detail.
All of the above elements in water-soluble and acid-soluble components of airborne particulate matter could be satisfactorily determined. The acid-insoluble components left behind on the glass fiber filter were also analysed by procedures involving sodium carbonate fusion. The ICP method was proved to be sensitive enough to yield accurate and precise results on the concentrations normally encountered. However, the filter contains relatively high levels of metallic impurities. A blank correction was required to obtain acceptable results. The same technique, with appropriate modifications, can be applied for the analysis of airborne particulate matter collected on other filter materials; i.e., a cellulose paper filter, an organic membrane filter, and so forth.

View full abstract