No abstract

The residual contents of fluoroquinolones in fish and shrimp were analyzed by using HPLC-FLD and LC-MS. The limit of detection (LOD) and limit of quantification (LOQ) for fluoroquinolones by HPLC-FLD were 0.0030-0.0083 and 0.0090-0.0252 mg/kg, respectively. Those by LC-MS were 0.0019-0.0040 and 0.0059-0.0122 mg/kg, respectively. Recoveries regarding ofloxacin, norfloxacin, pefloxacin, ciprofloxacin and enrofloxacin ranged from 76.4-104.6%. The detection rate of fluoroquinolones was 7.5% from a total of 268 samples. In only one Korean bullhead sample, the sum of ciprofloxacin and enrofloxacin contents was detected at a higher level than its maximum residue limits (MRL) of 0.1 mg/kg. Ofloxacin, norfloxacin and pefloxacin were not detected in any samples and detection rates of ciprofloxacin and enrofloxacin were 3.4% and 6.7%, respectively. In detection rate by species eel (2.6%), loach (2.2%), Korean bullhead (1.5%), carp (0.7%) and snakehead (0.4%) were in order.

Dietary exposure assessment by ages was performed in this study using pesticide residues data examined in vegetable commodities collected in Seoul from 2007 to 2009, and the vegetable intakes for Seoulites which were obtained after analysing the Korea National Health and Nutrition examination survey data of 2008. There was a statistical difference for vegetable intakes by ages (P<0.001). Vegetable intake was the highest in 40~59 age group and was the lowest in under 5 age group. The %ADI was calculated using vegetable pesticide residues and vegetable intake for Seoulites by ages. Considering below 1 of the %ADI by ages, the risk caused by pesticide residues in vegetables was very low and vegetable intake was safe. Key words

In this study, we monitored total mercury and methylmercury concentrations in tuna, billfish, and deep-sea fish distributed in Seoul city. With the acquired data, we carried out statistical analysis and an exposure assessment for intake. The mean concentrations (mg/kg) of total mercury and methylmercury were 0.32±0.31/0.20±0.20 for tuna, 0.43±0.48/0.20 ±0.17 for patagonian toothfish, 0.99±0.72/0.51±0.40 for billfish and 1.20±0.70/0.95±0.51 for sharks, respectively. We found that sharks, billfish, patagonian toothfish, and tuna were more contaminated with total mercury and methylmercury, in sequence, and that 66% of the total mercury concentration consisted of methylmercury, on average. Although the estimated weekly intakes of methylmercury from commercial deep-sea fish were lower than the weekly intakes recommended by the Joint FAO/WHO Expert Committee on Food Additives (JECFA), we identified that the total mercury and methylmercury concentrations in tuna, billfish, and deep-sea fish continued to increase with the passage of time. Therefore, we confirmed the necessity of continuous monitoring and comprehensive analysis for general safety.

The characteristics of pesticide residues were examined in 18,069 samples from 91 vegetable commodities collected in Seoul from 2007 to 2009, and the vegetable dietary intakes of Seoulites were estimated using the Korea National Health and Nutrition examination survey data from 2008. The hazard index was calculated using vegetable pesticide residues and dietary vegetable intake by Seoulites. Detection rates for pesticide residues in vegetables were 11. KEY WORDS: exposure assessment, pesticide residues, vegetable intakes, hazard index.