• Korean Journal of Food Science and Technology
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• v.38 no.4
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• pp.599-603
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• 2006

This study investigated the efficacy of common sanitizers and disinfectants on E. coli, Staphylococcus aureus, Listeria monocytogenes and Salmonella Typhimurium spiked on the surface of the main processing machine. All four microorganisms were greatly reduced by hydrogen peroxide (1,100 ppm), iodophors (25 ppm) and quarternary ammonium compounds (200 ppm). The reduction levels of E. coli, S. aureus, S. Typhimurium, and L. monocytogenes were 3.5, 3.4, 3.0, and 2.8 $log_{10}CFU/100cm^2$, respectively. Peroxy compounds and quaternary ammonium compounds can be applied to animal food manufacturing plants as a good sanitizer.

• Korean Journal of Food Science and Technology
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• v.37 no.6
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• pp.1042-1047
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• 2005

Effects of sanitizers and disinfectants on microorganisms in food-processing plants were investigated. Chlorine and hydrogen peroxide were most effective, showing approximately 2-3 log reductions, among products tested, whereas alcohol showed less than 1 log reduction. Before using sanitizer and disinfectant in food processing plants, aerobic plate, coliforms, and E. coli counts were about $10^1-10^5,\;10^1-10^2$, and below $10\;CFU/cm^2$, respectively. After use of sanitizer, APC decreased to $10^1-10^2$. The result to confirm sanitizing effectiveness for 2 months using showed that Alcohol compound, QAC, hydrogen peroxide compound were effective against Staphylococcus aureus ATCC 6538 and E. coli ATCC 10536 at recommended usage concentrations, whereas effectiveness of chlorine compound decreased from 8 to 4 log 2 weeks after opening of product. Although sanitizers and disinfectants approved by law showed 5 log reduction in vitro for S. aureus ATCC 6538 and E, coli ATCC 10536, sanitizing effectiveness in food processing plants was very low, and effectiveness decreased once used product was stored.

• Environmental Engineering Research
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• v.18 no.4
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• pp.253-257
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• 2013

Exposure assessment for three major active ingredients used for humidifier disinfectants, polyhexamethylene guanidine (PHMG), oligo(2-(2-ethoxy)ethoxyethyl guanidinium chloride (PGH), and 5-chloro-2-methylisothiazol-3(2H)-one/2-methylisothiazol-3(2H)-one (CMIT/MIT) mixture, was conducted in a bedroom using an air sampler for a refined risk assessment. The experimental site was selected to reflect consumer exposure conditions. Aerosols formed by a humidifier were sampled during 8 hr at 7.5 L/min. Absorbed PHMG and PGH by the sampler were quantified using a spectrophotometric method, and high performance liquid chromatography-ultraviolet detection was used for CMIT/MIT. Three exposure scenarios were assumed for adding humidifier disinfectants to the humidifier water at 1, 2, and 10 times the volume recommended by the product suppliers, and the humidifier was on at its maximum rate of producing aerosols in order to consider reasonable worst-cases. The sampled mass of PHMG and PGH ranged 200 to $2,800{\mu}g$ and 140 to $1,900{\mu}g$, respectively, under different exposure conditions, whereas the absorbed mass of CMIT/MIT was barely detected at the detection limit of 0.11/0.29 mg/L, only at 10 times the recommended level. The resulting risk quotients for PHMG and PGH ranged 1,400 to 20,000 and 1,000 to 13,000, indicating that health risks could be significant. For CMIT/MIT mixture, risk quotients were much smaller than estimated by assuming that they are conservative in the indoor environment, probably due to oxidative reactions. The refined exposure assessment presented here may provide a useful tool for assessing risks posed by active ingredients in spray-type biocidal products.

• Journal of Korean Society of Environmental Engineers
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• v.29 no.5
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• pp.533-539
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• 2007

Cell culture infectivity assay using HCT-8 cell was combined with most-probable-number technique to evaluate the inactivation of Cryptosporidium parvum by various disinfectants, including chlorine, ozone, and UV light. The assay was demonstrated to be as sensitive as animal infectivity assay, which has been considered the "gold standard" for assessing Cryptosporidium oocyst infectivity, and a valuable tool to evaluate inactivation of C. parvum by disinfectants. Bench-scale inactivation study showed that at the condition of $5^{\circ}C$ and pH 7.0, CT value of $1,250mg{\cdot}min/L$ by chlorine and $16mg{\cdot}min/L$ by ozone were required to achieve approximately 1.0 log inactivation of C. parvum, suggesting that even ozone could not be sufficient to inactivate C, parvum at low. temperature. Unlike chlorine and ozone, UV light is very effective to inactivate C. parvum, regardless of temperature. A UV light dose of 2 $mJ/cm^2$ provided at least 3 log inactivation of C. parvum.

• Journal of Environmental Health Sciences
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• v.45 no.3
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• pp.273-284
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• 2019

Objective: This study was performed to estimate the number of those who used humidifier disinfectants (HDs) and experienced health effects from exposure to HDs in Korea between 1994 and 2011. Methods: A nationwide interview survey was conducted for the representative sample to identify the proportion of those who used HDs among the general population (n=3,001). Another online survey was conducted for those exposed to HDs to find the proportion of those who experienced health effects among those who were exposed to HDs (n=3,993). Statistics for population size by region and year (1994-2011) were used to estimate the cumulative number of those exposed to HDs and those who experienced health effects. In terms of the proportion of those exposed to HDs, those less than 30 years of age were excluded due to an issue related to information bias. Various approaches for estimation included the capture-recapture method for estimation of those who experienced health effects. Results: The cumulative proportion of those exposed to HDs was 6.7% among the general population, and the proportion of those who experienced health effects among those who were exposed to HDs was 13.9%. Based on these factors, it was estimated that 3.5 to 4.0 million people were exposed to HDs and 350 to 400 thousand experienced health effects at least requiring visiting a hospital. Conclusion: It is suggested that a nationwide representative sample may be essential for population size estimation of those exposed to environmental risk factors and of those who experienced health effects.

• Journal of Environmental Health Sciences
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• v.45 no.1
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• pp.71-81
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• 2019

Objectives: The lung injuries by exposure to the humidifier disinfectants (HDs) were reported in 2011, Korea. For the HD victims, environmental exposure level and clinical diagnosis were conducted to determine the levels of damage by HDs. Methods: The exposure assessment to the HDs from 1st to 4th questionnaire surveys were carried out for 5,245 victims. And the affecting factors of exposure levels were analyzed by characterizing exposure and demographic information. By using of exposure concentration and cumulative time, exposure levels were classified and compared by percentage of clinical diagnosis classes. The high exposure and low clinical diagnosis rating groups, and low exposure and high clinical diagnosis rating groups were analyzed to overcome the limitation of past exposure assessment such as recall bias. Results: Among the all applicants damaged by the humidifier disinfectants, survivors were 4,028 and the dead were 1,217. And male and female were 2,675, and 2,547, respectively. In case of occurrence age of lung disease, under 10 years was majority age group (1,536) and followed by thirties (917). Pregnant women and fetuses were 339 and 439, respectively. And the damages by exposure to the HDs were concentrated on these susceptible populations in groups with low exposure and high clinical diagnosis rating. On the other hand, the groups classified by high exposure and low clinical diagnosis rating were shown different characterization. Conclusions: The questionnaire survey on past exposure may be uncertain due to recall bias. However, the relationship between classified exposure levels and clinical diagnosis ratings might be shown positive correlation if the exposure assessment errors were analyzed and controlled.

• Korean Journal of Ecology and Environment
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• v.55 no.4
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• pp.376-389
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• 2022

Despite the consumption of disinfectants have been increased by COVID-19 pandemic, the fate of the chemicals in aquatic food webs are still unclear. In order to understand the trophic transfer of the chemicals, the concentration of disinfectants including six benzalkonium chloride (BACs) and five didecyldimethylammonium chlorides(DDACs) were measured at the Geum (2020), Han (2021), and Yeongsan River (2021), before and after rainfall. The highest concentration of ∑BACs (mainly C12 and C14) and ∑DDACs (mainly C10 and C14) were observed in the Han River, followed by Yeongsan River, Geum River Estuary, and Gapcheon. After rainfalls, both concentration and detection frequency were decreased in all sites. Although the BAC and DDAC seems to be accumulated in organisms, they were bio-diluted rather than magnified in the aquatic food web with the biomagnification factor(BMF) of less than 1, trophic magnification slope (TMS) from -0.236 to 0.001, and trophic magnification factor(TMF) from 0.85 to 1.01.

• Korean Journal of Plant Resources
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• v.36 no.1
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• pp.100-106
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• 2023

In order to control the fire blight disease, all plants within the radius of the diseased orchard were removed in the early stage of the outbreak, or antibiotics control was performed for prevention. Since the beginning of antibiotics use on plants, the potential for development of resistance to antibiotics by the plant pathogen and unintended detrimental effects on the fruit trees and environment has become a problem. The purpose of this study is to determine the degree of phytotoxicity to fruit trees caused by excessive spraying of the fire blight disease disinfectant and to establish basic data for safe disinfectant guide. We analyzed whether damage to the fruit tree and the maximum residual limit of fruit was exceeded when three kinds of the fire blight disease disinfectants were continuously sprayed in excess of the number of safe use during the growing season. There was no phytotoxicity in apple 'Fuji' and pear 'Niitaka', and oxolinic acid was detected beyond the limit of quantitation in 'Fuji' grown without a bag, and the other disinfectants were detected below the maximum residue limit. When these disinfectants are continuously sprayed in excess of the number of safe, phytotoxicity may remain on the fruit. Therefore, it is necessary to observe the prescribed dilution factor and observe the safe frequency and the timing of use.

• Journal of Food Hygiene and Safety
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• v.38 no.6
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• pp.508-516
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• 2023

The consumption of enoki mushrooms has been associated with cases of listeriosis produced by Listeria monocytogenes, highlighting the significance of sanitizing food-contact surface, such as the velcro used in welding processing of enoki mushrooms, to ensure microbial safety. We investigated the inhibitory activity of nine chemical disinfectants at regular concentrations against L. monocytogenes isolated from a mushroom farm environment. The bacterial suspension was prepared in phosphate buffered saline and mushroom extract broth and inoculated onto the velcro surface. After inoculation, most disinfectants reduced the initial 8 log CFU/coupon concentration by less than 2 log CFU/coupon during a 5-min treatment. Slightly acidic hypochlorous water showed a reduction of approximately 4 log CFU/coupon when tested for more than 30 min at the maximum allowable concentration of 200 mg/L. Sodium hypochlorite solution showed a reduction of approximately 5 log CFU/coupon when used at 100 mg/L for 60 min. Peracetic acid, at the maximum allowable concentration of 300 mg/L, showed the most effective reduction of 5 log CFU/coupon or more when the surface was treated with 37.5 mg/L for 30 min. These results indicate that peracetic acid can be used as the disinfectant strategy to control cross-contamination of L. monocytogenes on the velcro surface of plastic wrappers used in the welding processing of enoki mushrooms.

• Proceedings of the Korean Society of Life Science Conference
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• 2005.09a
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• pp.60-60
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• 2005