Tag Archives: Korea

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A Model for Developing Water and Sanitation Capacity

PFAS Exposure via Water, Inhalation, Diet, and House Dust, Korea

Tian Z, Kim SK, Shoeib M, Oh JE, Park JE. Human exposure to per- and polyfluoroalkyl substances (PFASs) via house dust in Korea: Implication to exposure pathway. The Science of the total environment. 2016 Feb 27;553:266-275. doi: 10.1016/j.scitotenv.2016.02.087.

A wide range of per- and polyfluoroalkyl substances (PFASs), including fluorotelomer alcohols (FTOHs), perfluorooctane sulfonamidoethanols (FOSEs), perfluoroalkyl carboxylic acids (PFCAs), and perfluoroalkane sulfonic acids (PFSAs), were measured in fifteen house dust and two nonresidential indoor dust of Korea. Total concentrations of PFASs in house dust ranged from 29.9 to 97.6ngg-1, with a dominance of perfluorooctane sulfonic acid (PFOS), followed by 8:2 FTOH, N-Ethyl perfluorooctane sulfonamidoethanol (EtFOSE), perfluoroctanoic acid (PFOA). In a typical exposure scenario, the estimated daily intakes (EDIs) of total PFASs via house dust ingestion were 2.83ngd-1 for toddlers and 1.13ngd-1 for adults, which were within the range of the mean EDIs reported from several countries. For PFOA and PFOS exposure via house dust ingestion, indirect exposure (via precursors) was a minor contributor, accounting for 5% and 12%, respectively. An aggregated exposure (hereafter, overall-EDIs) of PFOA and PFOS occurring via all pathways, estimated using data compiled from the literature, were 53.6 and 14.8ngd-1 for toddlers, and 20.5 and 40.6ngd-1 for adults, respectively, in a typical scenario. These overall-EDIs corresponded to 82% (PFOA) and 92% (PFOS) of a pharmacokinetic model-based EDIs estimated from adults’ serum data. Direct dietary exposure was a major contributor (>89% of overall-EDI) to PFOS in both toddlers and adults, and PFOA in toddlers. As for PFOA exposure of adults, however direct exposure via tap water drinking (37%) and indirect exposure via inhalation (22%) were as important as direct dietary exposure (41%). House dust-ingested exposure (direct+indirect) was responsible for 5% (PFOS in toddlers) and <1% (PFOS in adults, and PFOA in both toddlers and adults) of the overall-EDIs. In conclusion, house-dust ingestion was a minor contributor in this study, but should not be ignored for toddlers’ PFOS exposure due to its significance in the worst-case scenario.

Arsenic Intake for Diet in Korean Adults

Seo MN, Lee SG, Eom SY, Kim J, Oh SY, Kwon HJ, Kim H, Choi BS, Yu IJ, Park JD. Estimation of Total and Inorganic Arsenic Intake from the Diet in Korean Adults. Archives of Environmental Contamination and Toxicology. 2015 Dec 26.

Arsenic (As) is a major environmental pollutant and a known human carcinogen that is widely distributed in the air, soil, and water. General population is mainly exposed to As through drinking water and food from the contaminated water and soil. Arsenic in drinking water is generally well controlled now. This study was performed to estimate total and inorganic As intake and to determine the major contributing source in the Korean adult diet. The study subjects were 2117 healthy adults (922 males and 1195 females) who had not been occupationally exposed to As. Total dietary intake was studied using the 24-h recall method, which included 138 specific food items. The estimates of total As and inorganic As intake were based on total and inorganic As contents in each food item consumed during the last 24 h. Daily dietary intake was estimated to be 1373.6 g. Total As intake was estimated to be 145.4 µg As/day. Total dietary As intake was correlated with consumption of fish/shellfish, seaweeds, and grains. Approximately 87 % of total dietary As intake was attributed to seafood, such as 105.5 µg As/day from fish/shellfish and 20.5 µg As/day from seaweeds. Inorganic As intake was estimated to be 10.4 µg As per day. Inorganic As intake was mainly provided by grains (6.4 µg As/day), followed by seaweeds and fish/shellfish. Our results indicate that seafood and grains are the main As dietary sources in Korean adults and that dietary As exposure may be associated with individual dietary habits and environmental As contamination among countries.

Korean Fluoride Study Design Inconclusive on Communal Fluoridation

This type of study is typical of those conducted to support fluoride addition to drinking water. But such a study design cannot answer the question as to efficacy and effectiveness of communal fluoridation.  Typically such studies end up concluding what has already been assumed from the beginning.

Kim MJ, Kim HN, Jun EJ, Ha JE, Han DH, Kim JB. Association between estimated fluoride intake and dental caries prevalence among 5-year-old children in Korea. BMC oral health. 2015 Dec 30;15(1):169. doi: 10.1186/s12903-015-0153-0.

BACKGROUND: The purposes of this study were to estimate the fluoride intake from food and drink in 5-year-old Korean children, and to measure the association between estimated fluoride intake and dental caries prevalence.

METHODS: The study involved a secondary analysis of raw data from the 4(th) Korea National Health and Nutrition Examination Survey (KNHANES; 2007-2009). The study subjects were 167 boys and 147 girls aged 5 years who had undergone both physical and nutritional examination as part of the survey. The KNHANES comprised a health questionnaire, a physical examination, and a nutritional examination. The nutritional examination of KNHANES consisted of 3 parts: a dietary life survey, a food-frequency questionnaire, and a food intake investigation. The food intake investigation used the 24-h recall method, with information being provided by the children’s parents. On the basis of this information, we evaluated the fluoride content in a total of 310 food items using the hexamethyldisiloxane (HMDS)-facilitated diffusion method, modified using Taves’ microdiffusion method. As part of the KNHANES survey, oral examinations were conducted at a mobile examination centre by trained dentists using dental mirrors under a fluorescent light. These examinations were performed using methods proposed by the World Health Organization.

RESULTS: The dietary fluoride intake of 5-year-old Korean children was estimated to be 0.35 mg/day, or 0.016 mg/kg/day. The “decayed or filled surfaces” (dfs) indices of primary teeth were higher in children who had a lower dietary intake of fluoride. There was a significant inverse association between dietary fluoride intake and the prevalence of dental caries.

CONCLUSION: The inverse association between dietary fluoride intake levels and prevalence of dental caries implies that the introduction of community caries prevention programmes may be beneficial. Such programmes would include water fluoridation and a fluoride supplementation programme.

Perfluoroalkyl acids in Seafood and Water, Korea

Heo JJ, Lee JW, Kim SK, Oh JE. Foodstuff analyses show that seafood and water are major perfluoroalkyl acids (PFAAs) sources to humans in Korea. Journal of hazardous materials 2014 Aug 30;279:402-9. doi: 10.1016/j.jhazmat.2014.07.004.

We measured concentrations of PFAAs in 397 foods, of 66 types, in Korea, and determined the daily human dietary PFAAs intake and the contribution of each foodstuff to that intake. The PFAAs concentration in the 66 different food types ranged from below the detection limit to 48.3ng/g. Perfluorooctane sulfonate (PFOS) and long-chain perfluorocarboxylic acids (PFCAs) were the dominant PFAAs in fish, shellfish, and processed foods, while perfluorooctanoic acid (PFOA) and short-chain PFCAs dominated dairy foodstuffs and beverages. The Korean adult dietary intake ranges, estimated for a range of scenarios, were 0.60-3.03 and 0.17-1.68ngkg(-1)bwd(-1) for PFOS and PFOA, respectively, which were lower than the total daily intake limits suggested by European Food Safety Authority (PFOS: 150ngkg(-1)bwd(-1); PFOA: 1500ngkg(-1)bwd(-1)). The major contributors to PFAAs dietary exposure varied with subject age and PFAAs. For example, fish was a major contributor of PFOS but dairy foods were major contributors of PFOA. However, tap water was a major contributor to PFOA intake when it was the main source of drinking water (rather than bottled water).

Click here for full paper (Open Access).

Cadmium Exposure for Residents of Abandoned Metal Mine, Korea

Yang J, Kim EC, Shin DC, Jo SJ, Lim YW. Human exposure and risk assessment of cadmium for residents of abandoned metal mine areas in Korea. Environ Geochem Health. 2014 Sep 26.

The objective of this study is to find the Cd levels in agricultural crops compared to soil, to evaluate the relationship between daily intake dose through the multimedia/multi-pathway of human exposure and biomarker levels of the residents in mine vicinity area. We collected and cited the data of four out of ten health impact assessments for the residents of abandoned mine areas undertaken by the Korea Ministry of Environment in 2008. The Cd levels in soil were significantly decreased by the separation distance from the mines. The Cd levels in blood were significantly different between residents in mine areas and in comparative areas, but urinary Cd levels did not differ. The Cd levels in blood were related to the age; the separation distance from mine to residence; the daily intake dose via ingestion of drinking water, crops, and surface soil; and inhalation of ambient air of Cd, but urinary Cd levels were not relevant with various sociodemographic characteristics and exposure factors. The average hazard quotient (HQ) value of Cd in the mining site was below 1.0, but the maximum HQ was closed to 1.0. The results indicated that the ingestion of Cd-contaminated soil and agricultural crops by local inhabitants could pose potential adverse health effects to long-term residents consuming rice grown near to the mining areas.

Click here for full paper (fee).

Seoul (Korea) issues tap water warning…

“A recent outbreak of algae in Seoul’s water reservoirs has led the city  government to issue a water quality advisory amid public anxiety, authorities  said.”

“The Seoul Metropolitan Government issued its first algae advisory in four  years Thursday for some parts of the Han River that runs through the capital  city, while some city residents were stocking up on bottled water, Yonhap News  Agency reported.”

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