Effect of washing, soaking, and cooking methods on perfluorinated compounds in mackerel (Scomber japonicus).

Perfluorinated compounds (PFCs) are environmental pollutants, and dietary intake is a major route of human exposure to them. We aimed to see the effects of washing, soaking, and cooking (grilling, braising, frying, and steaming) on the change of PFCs in mackerel fillets and PFCs before and after each treatment were analyzed using LC-MS/MS. Washing resulted in a decrease in the PFC content of mackerel (average 74%) comparing to control. Among the 19 PFCs detected, perfluorobutanoic acid and perfluorotridecanoic acid (PFTrDA) were found to be abundant after washing. Soaking mackerel in sake reduced its PFC content by 51%, whereas soaking in rice-washed solution reduced by 80% comparing to control. All the four cooking methods were effective in reducing the PFC content of mackerel. The degree by which the PFC content decreased varied with the cooking method: grilling (91%), steaming (75%), frying (58%), and braising (47%) comparing to uncooked sample. In addition, when mackerel was braised with potato, PFCs decreased more in fillet than the ones without potato. PFCs in potato increased after cooking with mackerel. The excessive consumption through the mackerel was 0.1997 ng/kg bw/day and 0.7987 ng/kg bw/day, respectively. These exposure levels were well below the tolerable daily intake values of both compounds (PFOS, 150 ng/kg bw/day; PFOA, 1,500 ng/kg bw/day). The results of this study indicated that employing appropriate pretreatment and cooking methods could be an effective way to reduce the dietary exposure to PFCs in mackerel.

Comparative analysis of lead content during food processing.

Heavy metals in groups 3-16 in periods 4 and greater. They exist naturally in the earth's crust. People are exposed to heavy metals by the inhalation of polluted air and via the intake of contaminated food. People are exposed to lead (Pb), one of heavy metals, by consuming foods that are contaminated from the environment. Pb is ubiquitous in the environment and accumulates in plants and animals that eat contaminated plants. The Pb in foods before and after processing were analyzed via Inductively coupled plasma with mass spectrometry to determine the effects of the procedures on the Pb migration and residue. This analytical method was verified to have a limit of detection of 0.011-0.859 µg/kg, acceptable linearity with the regression coefficient of 0.999, relative recoveries of 78.1-89.9% and repeatability of 1.4-7.7%. The amount of Pb was reduced during the following processes: more than 79.6% by extracting ginseng, extracting red ginseng and balloon flower roots via alcohol, more than 47.9% by blanching Chwinamul, more than 18.2% by brewing coffee with cold and hot water, more than 22.2% by extracting juices from fruits and peeling fruits. Therefore, proper cooking and food processing can be advantageous in terms of reducing exposure to Pb.

Assessment of Tetrabromobisphenol and Hexabromocyclododecanes exposure and risk characterization using occurrence data in foods.

Tetrabromobisphenol A (TBBPA) and Hexabromocyclododecanes (HBCDs) are two of the most used BFRs and they have cumulated in the environment. TBBPA and HBCDs in food were determined and their risks were assessed. The analytical method used was validated in different food categories, and the performance parameters were acceptable based on the criteria of AOAC. Fish and cephalopods were contaminated with TBBPA higher than other foods, and fish contained higher levels of HBCDs than other foods. α-HBCD was the predominant diastereomer in fish and meat and had strong correlations with HBCDs in fish and cephalopods. HBCDs accumulated easier than TBBPA in food. People were exposed to TBBPA from 0.125 ng kg-1 b.w. day-1 to 0.284 ng kg-1 b.w. day-1 and HBCDs from 0.353 ng kg-1 b.w. day-1 to 1.006 ng kg-1 b.w. day-1 via food and air. Food mainly contributed to exposure to TBBPA and HBCDs and vegetables were the main contributors for exposure to TBBPA and HBCDs in food. MOEs for the whole population were over 100, and the risks of exposure to TBBPA and HBCDs from food and the environment were of low concern to public health.

Development of an analytical method for simultaneously determining TBBPA and HBCDs in various foods.

Tetrabromobisphenol A (TBBPA) and Hexabromocyclododecanes (HBCDs) are commonly used as brominated flame retardants in large volumes, and accumulate in plants and animals in the environment, and people are exposed to them when consuming food. As many countries are monitoring them in food, it is necessary to develop a method to analyze them simultaneously for cost efficiency. A method was developed and optimized under different conditions using accelerated solvent extraction to extract the lipids from the samples, acid silica column to clean the samples and liquid chromatography coupled with tandem mass spectrometry to determine TBBPA and HBCDs. The method was validated in different kinds of food. Uncertainty of measurement was calculated by combining all uncertainties of contributors. Intermediate precision (reproducibility) was the most influential contributor to uncertainty. 5 food categories with 115 samples were analyzed with the method, and mackerels containing high level of fat were highly contaminated by TBBPA and HBCDs.

Methylmercury Determination in Fish by Direct Mercury Analyzer.

BACKGROUND: There are two methods for quantifying methylmercury (MeHg) in fish using GC-electron capture detection (ECD): AOAC INTERNATIONAL Official Method 988.11 and the Korean Food Code (KFC) method. Both of these methods consume a large amount of chemicals and require long pretreatment times because of several complicated MeHg extraction steps. OBJECTIVE: In this study, a new method for the simple and rapid determination of MeHg in fish has been developed. The method is based on the investigation of oxygen combustion-gold amalgamation using a direct mercury analyzer (DMA) after the complete removal of MeHg by organic extraction and back-extraction to an aqueous medium. METHODS: The DMA is suitable for the analysis of both solid and liquid materials and has a good detection limit. The developed method was validated by comparing the MeHg recoveries (%) of both certified reference materials and the market-purchased fish samples with the MeHg concentration obtained using the KFC method. RESULTS: The following parameters pertaining to the developed method were established: detection limit, 1.02 µg/kg; LOQ, 3.09 µg/kg; linearity (r), 0.9998; range, 0.1-300 µg/kg; and recovery, 95-97%. CONCLUSIONS: Our method is a promising alternative by virtue of its much simpler and faster sample pretreatment procedure, with a MeHg recovery as high as that of the KFC method. HIGHLIGHTS: The developed method enables the simultaneous analysis of total Hg and MeHg with only DMA equipment.

Reduction of total, organic, and inorganic arsenic content in Hizikia fusiforme (Hijiki).

This study aimed to evaluate the reduction of total, organic, and inorganic arsenic content in Hizikia fusiforme (hijiki). Initially, the six most common arsenic compounds in hijiki and its organs were evaluated, among which only arsenate and arsenobetaine were detected. Thereafter, the entire plant, including the stalk and leaves, was treated with heat and NaCl solution, individually and in combination. Heating at 90 °C for 5 min significantly reduced arsenic content in hijiki by approximately 33-80%. Treatment with NaCl solution significantly reduced arsenic content in hijiki, except for arsenobetaine content in the stalk. Combinatorial treatment further decreased arsenic content by more than 5-20%. In conclusion, consumption of hijiki after boiling at 90 °C and soaking in 2% NaCl solution reduces the intake of inorganic arsenic by consumers.

Simple validated method for simultaneous determination of deoxynivalenol, nivalenol, and their 3-ß-D-glucosides in baby formula and Korean rice wine via HPLC-UV with immunoaffinity cleanup.

A simple and reliable method for the simultaneous determination of major type B trichothecene mycotoxins, deoxynivalenol (DON) and nivalenol (NIV), along with their 3-ß-d-glucosides (DON-3-glucoside (DON3G) and NIV-3-glucoside (NIV3G)) in baby formula and Korean rice wine was validated in the present study. The method was based on immunoaffinity cleanup followed by analysis using an HPLC-UV technique. The method was validated in-house for two matrices as follows: linearity (R2 > 0.99) was established in the range of 20-1000 µg kg-1; accuracy (expressed as recovery) ranged from 78.7 to 106.5% for all the analytes; good intermediate precision (relative standard deviation < 12%), and adequate detection and quantitation limits (< 4.4 and < 13.3 µg kg-1, respectively) were achieved. Furthermore, the estimated measurement expanded uncertainty was determined to be 4-24%. The validated method was successfully applied to the analysis of 31 baby formulas and Korean rice wines marketed in Korea.

Comparing levels of perfluorinated compounds in processed marine products.

Perfluorinated compounds (PFCs) are widely distributed in nature and have many applications due to their unique chemical and physicochemical properties. While, PFCs are present in soil, water, and air, their pathway for entry into the human body is circumstantially via contaminated food. The demand for seafood has been increasing. In this study, we investigated via LC-MS/MS, the content of 19 different types of PFCs in 302 samples belonging to five different categories of the typical South Korean seafood. The highest levels of PFOA, PFTrDA, PFOS, and PFPeA were found in dried seafood, canned and salted seafood, processed fish food, and seasoned laver, respectively. The levels of PFOA and PFOS were compared on the basis of various criteria including the nomenclature, biological classification, and habitat of the source of seafood. High levels of PFOA and PFOS were detected in anchovy, sea squirt, and mackerel based on the nomenclature of raw seafood, in crustaceans based on the biological classification, and in demersal organisms based on the habitat. The human intake values of PFOA and PFOS from the processed marine products in South Korea were lower than the tolerable daily intake, indicating that the consumption of these processed seafood poses no immediate harm.

Exposure assessment to paralytic shellfish toxins through the shellfish consumption in Korea.

Paralytic shellfish poisoning is caused by saxitoxin and its analogues. The paralytic shellfish toxins (PSTs) are produced by marine dinoflagellates and can be accumulated in filter feeding shellfish, such as mussel, clam, oyster and ark shell. The worldwide regulatory limits for PSTs in shellfish are set at 80 µg STX eq./100 g meat and this is widely accepted as providing adequate public health protection. In this study, we have determined five individual PSTs (STX, GTX1, GTX2, GTX3 and GTX4) in shellfish using LC-MS/MS and assessed the human acute and chronic exposures to PSTs through shellfish consumption. Food consumption data was obtained from the Korea National Health and Nutrition Examination Survey (KNHANES 2010-2015). The acute exposure using a large portion size of 88 g/day (95th percentile for consumers only) with maximum toxin level of 198.7 µg/kg was 0.30 µg/kg bw. Even though we estimated the acute exposure with a conservative manner, it was below the ARfDs (0.5 or 0.7 µg STX eq./kg bw) proposed by the international organizations, representing 43-60% of the ARfDs. The chronic exposures using mean consumption data for whole population with mean concentration of PSTs were ranged from 0.002 to 0.026 µg STX eq./kg bw/day. For consumers only, the chronic exposures were in the range of 0.012-0.128 µg STX eq./kg bw/day.

Determination of plutonium isotopes (238,239,240Pu) and strontium (90Sr) in seafood using alpha spectrometry and liquid scintillation spectrometry.

The present study was carried out to survey the levels of plutonium isotopes (238,239,240Pu) and strontium (90Sr) in domestic seafood in Korea. In current, regulatory authorities have analyzed radionuclides, such as 134Cs, 137Cs and 131I, in domestic and imported food. However, people are concerned about contamination of other radionuclides, such as plutonium and strontium, in food. Furthermore, people who live in Korea have much concern about safety of seafood. Accordingly, in this study, we have investigated the activity concentrations of plutonium and strontium in seafood. For the analysis of plutonium isotopes and strontium, a rapid and reliable method developed from previous study was used. Applicability of the test method was verified by examining recovery, minimum detectable activity (MDA), analytical time, etc. Total 40 seafood samples were analyzed in 2014-2015. As a result, plutonium isotopes (238,239,240Pu) and strontium (90Sr) were not detected or below detection limits in seafood. The detection limits of plutonium isotopes and strontium-90 were 0.01 and 1 Bq/kg, respectively.