JP2001097807A - Method for suppressing bacteria in sandbox - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a frequently and safely applicable method for suppressing the proliferation of bacteria in the sand of a sandbox of a park, and the like, and safe to children playing in the sandbox. SOLUTION: Bacteria in the sand of a sandbox are suppressed by mixing an alkali metal carbonate or bicarbonate into the sand in an amount of 0.5-5 wt.% based on the sand.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for suppressing the growth of bacteria in sand in a sandbox such as a park.

[0002]

2. Description of the Related Art In sandboxes in parks and the like, harmful microorganisms are generated due to excretion of pets and the like, and the risk of infection of sandbox users by these microorganisms and unpleasant odors pose environmental health problems. I have. However, for microorganisms generated in the sandpit, the whole or part of the sand is replaced, washing is expensive, disinfection and disinfection using large equipment, and spraying of expensive disinfectants, etc. There is a problem that cannot be implemented frequently.

[0003]

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to solve the above-mentioned problems and to provide a method for suppressing the growth of bacteria in sand in a sandbox which can be carried out safely and frequently.

[0004]

The present invention provides a method for controlling bacteria in a sandbox, which comprises mixing an alkali metal carbonate or bicarbonate in the sandbox.

In the present invention, the alkali metal carbonate or bicarbonate is preferably mixed in an amount of 0.5 to 5% by weight, particularly 0.8 to 2% by weight based on the weight of the sand in the sandbox. If the amount is less than 0.5% by weight, the effect is hard to appear. 5
If the amount is more than 100% by weight, the effect is not changed even if the amount of the alkali metal carbonate or bicarbonate is further increased.

[0006] As a method of mixing the alkali metal carbonate or bicarbonate with the sand in the sandbox, the mixing may be performed manually or using a small cultivator. When sand is added to a new sandbox, new sand is added to an existing sandbox, or sand is replaced, mix sand and alkali metal carbonate or hydrogencarbonate in advance using a mixer, etc. The sand may be put in a sandbox together with the alkali metal carbonate or bicarbonate.

The alkali metal carbonate or bicarbonate in the present invention includes sodium carbonate, potassium carbonate,
Sodium hydrogen carbonate, potassium hydrogen carbonate and the like can be mentioned. Among them, alkali metal bicarbonate is particularly preferable because it is safe for a worker to handle and for a child to play in a sandbox.

In the present invention, the reason why the alkali metal carbonate or bicarbonate has the effect of suppressing the growth of bacteria contained in the sand in the sandbox is not necessarily clear, but is presumed as follows. In general, hydrogen ions can freely penetrate the cell wall of the cells, and the concentration of hydrogen ions inside and outside the cells is kept in equilibrium by diffusion. On the other hand, the optimum pH of general microorganisms is 2.
It is in the range of 5-9. However, by mixing an alkali metal bicarbonate in the sandbox, the extracellular pH is 9-1.
2 and the pH inside the cells changes to 9-12, and proteins such as enzymes necessary for the growth of the cells are denatured and the cells die or the cells are destroyed by physical shock or environmental changes such as drying. It is thought that it becomes easy to do.

[0009]

[Example] [Example 1] The effect of inhibiting the growth of bacteria when sodium hydrogen carbonate, sodium carbonate, potassium carbonate, and potassium hydrogen carbonate were added to sand containing bacteria, respectively, was confirmed as follows. . In addition, the measurement of the number of viable bacteria
The test was performed by the surface smear plate method based on the food hygiene test method.

[0010] Escherichia coli (E. coli) separated and identified from clinical samples for 1 kg of sand in a park actually used.
Bacterial solution (Bacterial solution concentration is about Mcfarland 6) 10m
1 was added and mixed. A plurality of 100 g of this was collected and placed in a transparent polyethylene bag. Nothing was added to one of the bags, which was used as a basic sample for comparison.
To each of the other bags, the additives shown in Table 1 were added at the concentrations shown in Table 1 (the ratio of the weight of the additives to the weight of the sand), and the bags were shaken well so that the additives became uniform in the sand. Was mixed.

For each sample obtained as described above, the number of general viable bacteria and the number of E. coli per 1 g of the sample were measured immediately after mixing (30 minutes to 1 hour after mixing) and after standing for 48 hours. The results are shown in Tables 1 and 2, respectively. The mixed sample was stored in a transparent polyethylene bag at room temperature (25 ° C.) in a dark place until the number of bacteria was measured. In addition, the number of bacteria is shown as an average value when measured twice.

Further, in order to evaluate the safety to the environment when each additive spills, 5 g of each additive is added to pure water 50c.
c at 25 ° C. with a pH meter (trade name: H
M30S, electrode: GST5311C, manufactured by Toa Denpa Kogyo KK). The results are shown in Table 1. In addition,
The pH described in the pH column of the basic data is the pH of each additive.
The pH of pure water used in measuring the pH was shown.

As shown in Tables 1 and 2, in the sample to which the bacterial inhibitor of the present invention was added, an effect of reducing the number of bacteria immediately after mixing the inhibitor was obtained. In particular, when 1.0% by weight is added, the number of bacteria is remarkably reduced immediately after mixing by allowing the sample to stand.

[0014]

[Table 1]

[0015]

[Table 2]

Example 2 A basic sample and a sample to which each additive shown in Table 3 was added at each concentration shown in Table 3 were produced in the same manner as in Example 1. Then, the number of general viable bacteria and the number of Escherichia coli of each sample after the maintenance were measured in the same manner as in Example 1 except that the sample was maintained at 35 ° C. for 48 hours instead of the room temperature. Table 3 shows the results. For comparison, 3 was used for the basic sample.
Both the number of bacteria before maintenance at 5 ° C. and the number of bacteria after maintenance for 48 hours were measured. In addition, the number of bacteria contained in the sand before adding the bacterial solution is also shown.

The number of general viable cells was measured on a standard agar medium, the number of E. coli cells was measured on a DHL agar medium, and the table shows the number of cells per gram of sand.

[0018]

[Table 3]

[Example 3] In Example 1, the pathogenic Escherichia coli O-1 isolated and identified from a clinical specimen was used instead of the bacterial solution of Escherichia coli.
57: The same procedure as in Example 1 was carried out except that 10 ml of a bacterial solution of H7 adjusted to a concentration of Macfarland 6 was added,
Base samples and samples to which sodium bicarbonate was added at the concentrations shown in Table 4 were prepared. Each sample was held in the same manner as in Example 1 and the number of bacteria was measured as in Example 1. Table 4 shows the results.

The measurement was carried out by counting the number of clear colonies on the Sorbit MC plate agar medium and confirming them by the serum antibody method. Table 4 shows the results.

[0021]

[Table 4]

[0022]

The carbonate or bicarbonate of an alkali metal is inexpensive and readily available, and in the method of the present invention, a sufficient amount of bacteria is used in an amount of about 0.5 to 5% by weight of the sand in the sandbox. The suppression effect is obtained. Therefore, sand purification in a sandbox in a park or the like, which could not be carried out frequently so far, can be carried out regularly in a relatively short period of time, and the sandbox can be kept hygienic.

In particular, alkali metal bicarbonate is
It is weakly alkaline even when dissolved in water and does not harm the human body by itself, so it is safe not only for workers but also for children playing in the sandbox.

 ────────────────────────────────────────────────── ─── Continuing on the front page (72) Inventor Juichi Arima 5-1-1 Makiyama, Tobata-ku, Kitakyushu-shi, Fukuoka F-term in Asahi Glass Co., Ltd. 4H011 AA02 BA01 BB18 BC20 DA02 DC05 DD07

Claims (2)

[Claims] 1. A method for controlling bacteria in a sandbox, comprising mixing an alkali metal carbonate or bicarbonate with sand in the sandbox. 2. An alkali metal carbonate or bicarbonate,
The method for controlling bacteria in a sandbox according to claim 1, wherein 0.5 to 5% by weight of the sand in the sandbox is mixed.