Report On Ethylene Oxide Used For Container Disinfection At Port

Studies have shown that ethylene oxide used for chemical gas disinfectant is beginning to be used to sterilize containers. For many years, it is widely used in the disinfection and sterilization of heat and moisture sensitive items due to its excellent bactericidal effect, strong penetrating ability and low temperature.

Chemical properties

Ethylene oxide is one of the simplest cyclic ethers, which belongs to the heterocyclic compound and is an important petrochemical product. Ethylene oxide is a colorless and transparent liquid at low temperature, and a colorless gas with ether pungent odor at room temperature. The vapor pressure of the gas is high, which can reach 141kPa at 30°C. This high vapor pressure determines the strong penetration of ethylene oxide during fumigation and disinfection. Ethylene oxide used for a fungicide, is itself toxic and can cause cancer over time. Ethylene oxide is flammable and explosive, and is not easy to be transported over long distances, so it has a strong regionality. 

Status quo at home and abroad

Ethylene oxide gas fumigation disinfection and sterilization methods have been successfully applied in the pharmaceutical industry, import and export trade, and hospital sterilization of equipment that is afraid of heat and humidity, but the research on the disinfection of import and export trade goods is not extensive enough. Studies have shown that ethylene oxide is a broad-spectrum, high-efficiency, strong penetrating chemical gas sterilant with little damage to sterilized items. In foreign countries, especially in European and American countries, ethylene oxide is widely used in the disinfection and sterilization of medical equipment, various fabrics, plastic products, fur products, etc. In China, in recent years, ethylene oxide has been used in the disinfection and sterilization of medical equipment in hospitals, the disinfection of articles in the foci of infectious diseases, and in the fur industry, pharmaceutical industry and food industry.

Question

With the development of foreign trade, a large number of freight containers enter and leave the port, which brings a series of hygienic problems that are difficult to control. Therefore, container cargo may become a vector for the transmission of pathogenic microorganisms and harmful insects. Therefore, certain areas or types of containerized goods require disinfection or insecticide measures. Studies have shown that ethylene oxide is a broad-spectrum, high ethylene oxide gas disinfectant belonging to the alkylating agent, and its mechanism of action is to inactivate microorganisms through the alkylation of microbial proteins, DNA and RNA, and can inhibit the activity of some microbial enzymes, including phosphate dehydrogenase, cholinesterase and choline oxidase, etc., hindering the normal metabolism of microorganisms. Ethylene oxide can effectively kill bacterial propagules, bacterial spores, mycobacteria, fungi and viruses; it also has the effect of killing harmful insects. Ethylene oxide used for disinfection of medical devices and disposable medical supplies that are not resistant to humidity and heat in hospitals has been reported in a large number of literatures. China has already used ethylene oxide to sterilize and treat export fur methods and equipment, but few The relevant literature reports of ethylene oxide in port container fumigation and disinfection have become a problem that needs urgent attention.

Reserch evidence

Shi Qinfu and others used ethylene oxide to sterilize the imported large marmot skin, and obtained a good sterilization effect. Hao Guang Fu et al. used ethylene oxide large-scale curtain fumigation to treat marmot skins in epidemic areas. The fumigation temperature was controlled at 20°C to 40°C, the relative humidity was between 50% and 80%, and the concentration of epoxy resin was 30% by volume. With 1.5kg/m3 ethane and 72h action time, the killing rate of Bacillus subtilis spores reached 99.99% in four fumigation times. These experimental results show that the effect of ethylene oxide used for disinfection is affected by various factors such as its concentration, sealing conditions, temperature and humidity, action time and the nature of the object to be disinfected. In the application of disinfection and sterilization of medical supplies, the conventional concentration is 500mg/L～1000mg/L, the temperature is 45℃～55℃, the relative humidity should be 60%～75%, and the best performance can be obtained under the condition of complete sealing. That is to say, the ethylene oxide used for port container disinfection can exert a strong effect after controlling the working conditions.

Conclusion

Therefore, if ethylene oxide is used for sterilization of entry-exit containers and waste articles at the port, conditions must be changed, the influence of various factors must be strictly controlled, and the sterilization conditions required for ethylene oxide sterilization must be met as far as possible under the premise of ensuring safety, which has certain feasibility for disinfection of entry and exit port containers.