This study was conducted to investigate the residue amount of harmful materials on the 153 commercial medical herbs in Gwangju area. It was performed using the GC-ECD, GC-NPD, GC-MSD and the LC-UVD,LC-FLD, LC-MSD to analyze 200 pesticides. The heavy metals were determined using a Mercury analyzer and AAS. The sulfur dioxides were analyzed by modified Monnier-Williams method. The residual pesticides were detected in 7samples, and were over MRLs (Maximum Risk Levels) in 2 samples (1.3%). The mean values of heavy metal contents (mg/kg) were Pb, 0.570; Cd, 0.081; As, 0.082; Hg, 0.0093. The measured values of Pb, As, Hg showed within MRLs. The excess samples of MRLs were 3 samples (changchul 2, cheongung 1) on Cd. The sulfur dioxides were over MRLs in 7 samples (4.6%), hwanggi and gugija. These results will be used to establish on the regulation of commercial medical herbs in Gwangju area.
Two pesticides commonly used in spinach were subjected to a field residue trial to ensure safety of terminal residues in the harvest. The residual patterns of two pesticides, which were Azoxystrobin and chlorpyrifos were examined after applying with the recommended dose and their DT50 were calculated. Also degradation patterns of pesticides at storage 4℃ were compared to those at 20℃, and removal rates of pesticides by washing spinach with water were measured. Biological half-lives of azoxystrobin and chlorpyrifos were 3.2~3.8 and 3.8~4.7 days, respectively.
During the storage period, the degradation patterns were appeared more obviously at 20℃ than 4℃. Removal rates of azoxystrobin and chlorpyrifos were 9.6~90.0% and 17.7~85.8% by various washing methods.
This study was conducted to establish a method to analyze azodicarbonamide (ADA) in wheat flour. A new method using high performance liquid chromatography (HPLC) was developed for the determination of ADA in wheat flour. The recovery rate was 91.93~97.54%. The limit of detection for ADA was 0.02 mg/kg and the limit of quantification was 0.05 mg/kg. The monitoring results for ADA contents using the established methods showed that it was detected as the low value of 0.95 mg/kg in one of 51 flour samples (detection rate : 2%), but not detected in 59 bakery samples. The detected ADA level was suitable to its usage standard, compared to the standard (45 mg/kg). Although the detection rate was very low, the established analytical method of ADA will contribute to the management of ADA in processed foods such as wheat flour and bakery.
This study was carried out to investigate the current status of pesticide residues in 3,988 agricultural products in the northern area of Seoul from January to December in 2009. 3,988 samples comprising 109 types of agricultural products were assessed via a multiresidue method to detect 272 pesticides. Pesticide residues were detected in 25.6% (1,021 of 3,988 samples), and the rate at which the detected residues violated the maximum residue levels (MRLs) of the Korean Food Code was 2.2% (89 of 3,988 samples). The agricultural products which exceeded their maximum residue limits were leek, ginseng, welsh onion, crown daisy and lettuce (leaf). Additionally, the most frequently detected pesticide that exceeded the regulation maximum was endosulfan, procymidone, tolclofos-methyl,iprodione and flutolanil.
A HPLC-MS/MS method was developed for simultaneous determination of six sweeteners (acesulfame-K, cyclamate, saccharin, sucralose, stevioside, aspartame) in children's favorite foods. The procedure involves an extraction of the six sweeteners with 50% methanol solution, sample clean-up using the Carrez clearing reagent and filtering with cartridge filter. The HPLC separation was performed on a Hypersil Gold (150 mm × 2.1 mm 5 um) column using the water/acetonitrile mobile phase (95:5). Mass spectrometric analysis was carried out using the TSQ Quantum Ultra operated in negative and positive ESI/SRM. With this method, good linear relationship, sensitivity and reproducibility were obtained. The spike recoveries of six sweeteners for 2 kinds of foods spiked into 0.4 mg/kg ranged from 87.4 to 114.7%. The detection limits were above 0.02 mg/kg. The method has been applied to determination of six sweeteners in children's favorite foods.
From April to December in 2009, microbial investigation is accomplished for 100 frozen foods asked to microbial control team that corresponds with total aerobic viable bacteria, coliform group, Escherichia coli,Enterococcus spp. and antibiotic resistance patterns of Enterococcus spp. isolates are investigated. Average of total aerobic viable bacteria numbers is 4.3 × 10⁴CFU/g. Average of coliform group numbers is 4.3 × 10³ CFU/g. Average of Enterococcus spp. numbers is 1.8 × 10³ CFU/g. Escherichia coli from 100 frozen foods is not detected and detection rate is 0.0%. 22 Enterococcus spp. are isolated from 100 frozen foods. 12 of 22 Enterococcus spp. strains are identified as E. faecium. 7 of 22 Enterococcus spp. strains are identified as E. faecalis. 2 of 22 Enterococcus spp.
strains are identified as E. gallinarum. 1 of 22 Enterococcus spp. strains is identified as E. hirae. Enterococcus spp.
isolates show a high resistance to erythromycin, rifampin, tetracycline, ciprofloxacin, chlorampenicol, penicillin and a susceptibility to vancomycin, ampicillin, gentamicin, strepomycin, linezolid. 15 of 22 Enterococcus spp. strains are multi-resistant and the most frequent multi-resistant pattern is erythromycin-rifampin for 6 Enterococcus spp. strains.
The epidemiology of reported food-borne disease (FBD) outbreaks from 2001 to 2008 in Korea and Japan were compared in this study. The outbreak rate of FBD in Japan was significantly higher although the average number of patient in each outbreak in Korea was much higher. In both countries, summer was the season when most FBD outbreaks occurred. The comparison study revealed that FBD outbreaks in spring were more frequent in Korea, and outbreaks in winter were more frequent in Japan. Almost half of FBD outbreaks were observed at restaurants in both countries while FBD outbreaks at schools and work-places in Korea were much higher than in Japan. The most frequent cause of bacterial FBDs in Korea was pathogenic Escherichia coli followed by Salmonella species. On the other hand, Campylobacter jejuni was the most frequent source of bacterial FBDs in Japan. Norovirus, which is related to uncontrolled hand hygiene and involvement of ill food workers, was the main cause of viral FBDs in both countries. In conclusion, there are common epidemiological characteristics as well as several differences in FBD outbreaks of Korea and Japan. These are suggested to be originated from the characteristic of climate, food sources, and life styles in two countries. Establishment of stricter control and surveillance system for FBD outbreaks are required for prevention and reduction of FBD outbreaks in both countries.
This study was performed to investigate awareness of hand washing, hand washing behavior, and the levels of indicator microorganisms on hands of food handlers who work in the food court and cafeteria of a university campus. The three methods used were questionnaire survey by interview, direct observation in restrooms, and microbiological examination according to the Food Code of Korea. A positive attitude toward hand washing compliance was reported by the responded food handlers; however, improper hand washing and poor hand hygiene of the food handlers were recognized by the unnoticed direct observation. Significant differences were found between the questionnaire survey and the direct observation (p < 0.05) in hand washing compliance after using the toilet, duration of hand washing, use of hand washing agent, washing different parts of the hands, hand-drying method, temperature of water, and method of turning off the water. Samples taken from their hands before work showed higher level of standard plate count, total and fecal coliforms, and Escherichia coli than those taken after washing with water. After washing hands with antiseptic liquid soap, the bacterial populations including Staphylococcus aureus on hands were dramatically reduced. This study indicates that there is a remarkable difference between the food handlers' awareness of hand washing and their hand washing behavior. Poor hand washing compliance and hand hygiene were indicated by the positive results of total and fecal coliforms, E. coli, and S. aureus on hands of some food handlers. The findings of this study suggest that the hand hygiene of the food handlers need to be improved. More training/education on hand washing and hand hygiene of the food handlers should be necessary.
Chronic exposure to Arsenic (As) causes significant human health effects including various cancers.
Total As concentrations from 300 polished rice samples cultivated near the mining areas in Korea were analyzed to estimate a probabilistic assessment of human health risk from As-contaminated rice. The mean of total As concentrations in rice was 0.09 mg/kg and lognormal distribution model was set for total As concentrations. Human health risk for As in rice was estimated using gender-specific rice consumption data and average daily dose (ADD). While cancer risk (CR) and hazard quotient (HQ) were calculated using oral cancer slope factor (OCSF) and Reference dose (RfD) suggested by the U.S. EPA. Mean of CR posed by total As was 2.16 (for male) and 1.83 (for female) per 10,000.
The HQ for general population from rice cultivated near the mining areas in Korea was below 1 as the 50th percentile of general population. However, less than 10% of general population consuming rice cultivated near the mining areas would exceed 1.0. This result is similar with those from each gender-specific group.
Domestic studies for identification of causality between children exposure to toxic chemicals, such as arsenic (As) and resulted hazardous effects were not implemented. This study was conducted to probabilistically estimate dietary As intake and health risk assessment for young children and all age-specific populations from the consumption of As-contaminated rice of Korea. Arsenic intakes for young children (1 to 6 years old) from As-contaminated rice were higher than other age-specific groups, based on a dose-per-body weight basis. Based on the current EPA cancer slope factor for As, estimated cancer risks (to the skin cancer) associated with dietary intake of As-contaminated rice for 1 to 2 years old group and 3 to years old group are 1.76 per 10,000 and 3.16 per 10,000, respectively, at the 50th percentile. Based on possible reference levels (0.005 mg/kg/day) for children, mean and 95th percentile value of HQ from rice for young children are very below 1.0, which is a regulatory limit of non-carcinogenic risks for human.
The purpose of this study was to examine the appearance of norovirus in the water for food in food service institutions and the influence of physicochemical and microbial factors of norovirus in order to work out basic data to predict the detection of norovirus. Among 82 samples of water for food in food service institutions, norovirus appeared in 7 samples and the rate of appearance was 8.5%. As for the type of norovirus, one samples contained GI type (genotype GI-6) and six samples contained GII type (genotype GII-2, GII-4, GII-12). In the regression model of prediction of norovirus, the rate of appearance was correlated with NH₃-N, total solids and the consumption of KMnO₄, out of such variables as NH₃-N, total solids, the consumption of KMnO4, depth, chloride and total colony counts, and its contribution rate for effectiveness was 78.60%. In order to examine the influential factor of environment upon the detection of norovirus, Pearson's correlation analysis was carried out. The predictable regression formula for appearance rate of norovirus was expressed as -1.818 + 42.677 [NH₃-N] + 0.023 [total solids] + 0.762[consumption of KMnO₄] -0.009 [depth] -0.146 [chloride] + 0.007 [total colony counts] (R = 0.904, R² = 0.818,adjusted R² = 0.786, p < 0.05). The most influential factors upon the detection of norovirus were NH₃-N, total solids and the consumption of KMnO₄. In other words, when the measured values of NH₃-N, total solids and the consumption of KMnO₄ were higher, the possibility of appearance of norovirus increased.
The compulsory beef labelling system has launched from January 1st 2007 by the amended Food Hygiene Law, we were checked the actual conditions of beef origin with a nationwide scale by the Hanwoo differentiation specific test method which was developed by Korea FDA using 90 SNP biomarkers. The test method is useful tool to differentiate the beef origin carrying out the mission of KFDA's annual food safety management guidance.
Also we have technically transferred the Hanwoo differentiation specific test method to other institutes as well regional KFDA and established the training program as a regular course in Korea Human Resource Development Institute for Health and Welfare. The beef used in this study were collected according to the 2009 Food safety guidance in roast beef restaurants where business site area greater than 100 m2. Total 216 samples were consisted of 48samples of the Seoul area and 168 of the region. The monitoring result from restaurants in all the region of Korea showed that 3 of 216 Hanwoo-labelled beefs were found out as a non-Hanwoo (1.3%). This results are gradually deceasing trend compared with 34.0% in 2005, 30.1% in 2006, 3.2% in 2007 and 5.14% in 2008. From these data, the Hanwoo differentiation specific test method on the settlement of the compulsory beef labelling system has an important role. As a outcome of this project, we might be considered the early settlement of the compulsory beef labelling system, technically transferred to other institutes and the establishment of regular training program of the test method.
This study was conducted to investigate for mineral contents, total polyphenol compounds,betaine, choline and DPPH free radical scavenging activity of halophyte. The mineral concentrations of Salicornia herbacea (top part) were Na 100,006 mg/kg, K 1,385 mg/kg, Mg 6,263 mg/kg, Ca 2,750 mg/kg, Fe 90.4 mg/kg, Mn 98.9 mg/kg, Zn 33.3 mg/kg, Cu 3.4 mg/kg respectively. And Suaeda Japonica (top part) were Na 85,332 mg/kg, K 710 mg/kg, Mg 7,005 mg/kg, Ca 4,344 mg/kg, Fe 1,434.9 mg/kg, Mn 119.1 mg/kg, Zn 19.2 mg/kg, Cu 2.7 mg/kg respectively. The betaine contents of Salicornia herbacea (top part) were 15.09 mg/g and Suaeda Japonica (top part)were 14.64 mg/g. The choline contents estimated by the DBAP-choline derivatives of Salicornia herbacea (top part)were 20.9 mg/100 g, Salicornia herbacea (root) were 23.4 mg/100 g, Suaeda Japonica (top part) were 23.1 mg/100g and Suaeda Japonica (root) were 23.8 mg/100 g. Total polyphenol compounds of Salicornia herbacea (top part) were high 36.0 mg/g in growth phase. The DPPH radical scavenging activities of methanol extract Salicornia herbacea (top part) were high 90.1% in growth phase. The frozen dried powder of Salicornia herbacea (top part) 1 g was equal to Quercetin 30.26 mg, Rutin 42.65 mg, TBHQ 20.32 mg, BHA 25.86 mg, BHT 40.75 mg, Ascorbic acid 22.86 mg in DPPH radical scavenging activities.
This study surveyed the change of housewives’ purchase behaviors by food safety incidents; the outbreak of 2008 Melamine incident in Korea as for example. 565 housewives in Gunsan were interviewed in March 2009. 52.3% of respondents were regarded as unsatisfactory for food safety management in Korea. Despite the result of scientific assessment for melamine, 74.6% of respondents were yet regarded as health-threatening substance. By the point of before, during and after Melamine-related food safety incident, we were surveyed the level of purchase for melamine-related food items as five scales, the results were 2.47 ± 0.97, 1.80 ± 0.92 and 1.62 ± 0.92, respectively (p < 0.001). After the incident happened, the purchase level was even more reduced. This study also found that there were significance difference (p < 0.05) among the respondents’ knowledge for melamine toxicity and food safety management in Korea concerning housewives’ purchase behaviors, i.e. the more accurately for melamine toxicity and higher satisfactory of consciousness of food safety, there were less change of purchase behaviors. In conclusion, the consciousness of food safety and accurate knowledge of hazards were significantly affected for the change of housewives’purchase behaviors by food safety incidents. Therefore, it can be suggested that the need for more scientific risk communication strategies with consumer.
In this study, monitoring of food additives as an artificial sweetener on favorite foods of children,which are deal at retail store and stationery store around eliminatory school, was performed. We analyzed aspartame,potassium acesulfame, sodium saccharin, and cyclamate from candys, biscuits, chocolates and others. Total 604 items as targeted food were collected from the other country; 285 items of candys, 131 items of biscuits, 74 items of chocolates.,114 items of others. Targeted foods were classified by manufacture nation; 308 samples from domestic products,211 from China, 26 from Indonesia, and 59 items from other nations. Artificial sweeteners were detected from 75 cases of food stuff which were 38 native product, 25 China, 9 Indonesia, and 3 others. The percentage of detected artificial sweeteners was aspartame 7.8% (47 cases), potassium acesulfame 3.0% (18 cases), sodium saccharin 1.8%(11 cases), and cyclamate 2.6% (16 cases). The detected concentration were followed [average(minimum-maximum)mg/kg]; aspartame 817 (21-4,988), potassium acesulfame 192 (24-1,136), sodium saccharin 91 (5-326), and cyclamate 926 (8-4,680). Aspartame was detected mainly on Korea foods, and cyclamate and sodium saccharin were detected from Indonesia food, artificial sweeteners were detected Chinese food, broadly. As a result, 17 cases were violated against regulatory standard of cyclamate, and sodium saccharin. Considering average body weight (36.9 kg)and daily intake of biscuits (15.6 g) for elementary student, ratio of estimated daily intake and acceptable daily intake was 0.86% for aspartame, 0.54% for potassium acesulfame, 0.77% for sodium saccharin, and 3.56% for cyclamate.
Pesticide residues were investigated in 16 commodities (rice, foxtail millet, buckwheat, kidney bean, peanut, sesame, orange, grapefruit, kiwifruit, spinach, perilla leaves, leek, garlic stem, garlic, ginger and oak mushroom)collected from 22 provinces (Seoul, Busan, Incheon, Daegu, Daejeon, Gwangju, Ulsan, Suwon, Seongnam, Goyang,Bucheon, Yongin, Cheongju, Jeonju, Jeju, Cheonan, Changwon, Pohang, Gumi, Jinju, Wonju and Yeosu) in 2009.
Pesticides (172 kinds) were analyzed using multiresidue method by GC/MS/MS from 510 samples, and phenthoate in kiwifruit was violated by exceeding MRL. The intake assessment for 24 kinds of pesticide residues including the detected pesticides at multi pesticide residue monitoring (bifenthrin etc.) were carried out. The result showed that the ratio of EDI (estimated daily intake) to ADI (acceptable daily intake) was 0.000007~0.458% which means that the detected pesticide residues were in a safe range so that residual pesticides in the agricultural products in Korea.