The consumption of Flammulina velutipes mushroom imported from Korea has been associated with the cases of listeriosis in the United States, Canada, and Australia. We investigated the effect of sanitizing the plastic wrapper (used in packaging F. velutipes) with slightly acidic electrolyzed water (SAEW) and ultraviolet C waterproof light-emitting diode (UVC-WLED) on reducing the Listeria monocytogenes. Further, the effect of UVC-LED on L. monocytogenes growth in F. velutipes at different storage temperatures (2, 4, and 10oC) was determined. The combined (SAEW+UVC-W-LED) treatment for 5–10 min reduced 99.9% of bacterial population from the contaminated plastic wrapper. In addition, the UVC-LED treatment for 3 min reduced the L. monocytogenes concentration in F. velutipes by 0.47 log CFU/g. Moreover, the growth of L. monocytogenes in the treated mushrooms was slower than that of the untreated (control) ones. L. monocytogenes concentration in F. velutipes increased over 3 log CFU/g at 2oC and 10oC for 60 and 10 days, respectively. The growth of L. monocytogenes at the bottom of mushrooms was faster than that at the top at both the temperatures. These results indicate that the combined SAEW+UVC-WLED treatment of plastic wrappers and the UVC-LED treatment of mushrooms can be used as potential hurdle technologies to control the risk of L. monocytogenes in mushrooms prior to packaging at farms.

Many people have often reused their disposable respirator multiple times due to reasons of economy and purchasing inconvenience. However, multiple use of a disposable respirator may lead to an adverse effect of its protection performance. In this study, we aimed to determine changes in the protection performance of disposable respirators related to multiple use and to suggest the appropriate number of times of use. The masks of the brands T and Y were selected in this study, respectively. A mask of each brand was used for testing at the same time and place for two hours per day. The protection performance of each disposable mask was tested after consecutive use on days two, three, and four. The protection performance tests for each used mask following wear on a mannequin were performed in the laboratory using GRIMM’s fine dust monitoring device and TSI’s nebulizer. The concentration of PM10, PM2.5, and PM1.0 inside and outside the mask was measured. The filtration rate was calculated and the results were analyzed using the SAS statistical program. The protection rates of the brandnew masks of T and Y brands (blank test) were 80% and 60%, respectively. After one-day usage, the protection rates of the brand-new T and Y branded masks significantly decreased from 80% to 60% and from 60% to 50%, respectively. Rather, the slight drops of protection rate were observed after two or more days of respirator use. Our findings indicate that the change of protection performance could occur after one-time use. It would not be recommended to use disposable respirators several times in terms of in terms of protecting human health from environmental hazards.