In this study, quality control was performed to analyze metal elements for sludge and water samples in livestock wastewater treatment plants. The detection and fate of 16 metal elements in influent, sludge and effluent were also evaluated. Method detection limit (MDL) and limit of quantification (LOQ) of target elements for sludge samples were 0.02-0.17 mg/kg and 0.07-0.56 mg/kg, respectively. For water samples, MDL and LOQ were 0.01-0.13 mg/L and 0.03-0.41 mg/L, respectively. Recoveries of metal elements were 67.6-113.6% for sludge samples and 87.7-120.6% for water samples, with a good precision. Metal elements for sludge samples were detected in a broad range. For example, some elements such as Ag, Cd, Co were below the LOQ. The concentrations of Pb, Cr, Cu, and Ni were 9.16-30.42 mg/kg, N.D-22.65 mg/kg, 364.26-1678.81 mg/kg, Ni N.D-32.37 mg/kg, respectively. For water samples, the concentrations of essential elements such as Ca, K, and Na were in the hundreds to thousands of mg/L range. Among some elements detected in the effluent, such as Al, Ca, Cu, Fe, K, Mg, Na, and Zn, the concentrations of regulated elements (Cu and Zn) were below the effluent water quality standards.

We categorized 78 hazardous polar organic compounds containing pharmaceuticals and personal care products (PPCPs), pesticides, and industrial chemicals potentially discharged into a river. We developed an automated online liquid chromatography-high resolution mass spectrometric (LC-HRMS) method for the rapid simultaneous determination of 78 polar organic compounds. The method was validated in terms of calibration curve linearity, limit of detection (LOD), limit of quantitation (LOQ), accuracy, and precision. The LOD and LOQ were in the range of 0.03-47.6 ng/L and 0.1-151 ‌ﾠng/L respectively. Good accuracy and precision were also obtained. The con‌ﾠcentrations of 78 compounds were determined in river water samples, and 60 compounds were detected. Caffeine was the most frequently observed PPCPs in river water.

Quality control systems of environmental testing laboratories are operated on the basis of proficiency tests and on-site assessments conducted in nine fields of testing laboratories. In this study, the assessment results of quality control systems present in environmental testing laboratories are analyzed with respect to their conformance with international standards(ISO/IEC 17025). The assessment results of quality control systems of 357 environmental testing laboratories indicate that the majority of the targeted laboratories meet the conformity requirements but 10 laboratories do not meet the conformity requirements. According to the score distribution, the waste testing laboratory and persistent organic pollutants testing laboratory have the highest scores of 88.2 points and 87.6 points, respectively. The air quality testing laboratory and odor testing laboratory have the lowest scores of 82.3 points and 80.1 points. Furthermore, the overall average score has increased from 84.0 points in the year 2012 to 85.4 points in the year 2016.

To evaluate the effectiveness of an olive oil adsorbent as an alternative adsorbent to triolein, we applied a Passive water-sampling device (PWSD) equipped with olive oil and triolein adsorbents to the highly polluted Geumho River basin. The olive oil adsorbent showed similar adsorption efficiencies (adsorption amount and pattern) for various micropollutants [i.e., brominated flame retardants (BFRs) and synthetic musk compounds (SMCs)] having different physico-chemical properties compared to the triolein adsorbent. The adsorption amount of the olive oil adsorbent for Σ27PBDEs ranged between 95 and 110%, Σ3HBCDs ranged between 91 and 105%, TBBPA ranged between 100 and 125%, and SMCs ranged between 110 to 125% compared to the triolein adsorbent. The adsorption patterns of each micropollutant in the olive oil adsorbent were quite similar to those in the triolein adsorbent, whereas the adsorption patterns in the adsorbents were somewhat different compared to those in the sediment according to the physico-chemical properties of each micropollutant. The concentration levels of BFRs in the Geumho River basin were mainly affected from the wastewater composition (i.e., textile, fabric, dyeing, and chemicals) of the influents of the sewage treatment plant (STP), whereas SMCs were estimated to be affected by the capacity of the STP and the discharging flow rate of the stream to the river. Therefore, we concluded that the olive oil adsorbent-containing PWSD is a highly cost-effective adsorbent compared to triolein for performing long-term monitoring of lipophilic micropollutants that have various physico-chemical properties (e.g., log Kow between 4 and 10).

To investigate the change in physic-chemical characteristics in the sediments of the Jinyang lake, surface sediments were collected and analyzed for concentrations of organic matters (IL, TOC, and TN) and metals (Al, Zn, Cr, Pb, Cu, Ni, As, and Cd), and for grain size at three sites in four different years (from 2015 to 2018). Our results indicate that the water depth was shallowest at the HS3 site from the Namgang dam and highest at the adjacent site. Since an increased in 2016, concentrations of organic matters did not changed notably and they were lowest at the HS3 and highest at the HS2 and HS1 sites. Concentrations of most metals decreased after the increase in 2016 and were lowest at the HS3 site. Sediments were mainly composed silt and sand, while the sediments at the HS3 site had a coarser composition. Correlation analysis show that water depth affected grain size, which again greatly affected the concentration of organic matters and metals. Based on these results, we propose that the shallowest site in the study area was strongly affected by flow velocity, which resulted in a decrease in fine sediments and, consequently, in a relatively low pollution of organic matters and metals as compared to the deeper sites.

Daecheong Lake plays a major role in securing water resources in the central region. This lake is experiencing problems due to the yearly occurrence of algae and therefore, long-term monitoring of the lake is conducted to analyze water quality and tidal characteristics. It is found that pollutants containing large amounts of nitrogen and phosphorus are scattered in the upper stream of the Okcheon Stream, which is a tributary. Cyanobacteria grow in significant quantities every year due to sewage treatment plants. We use a SWAT model to evaluate pollutant reduction for different load scenarios. Our findings generally support that Scenario 3, the Farm Management, Point Pollution Reduction and Creation of an Overland Pond method can control the pollutants most efficiently, thereby reducing the amount of nutrients that flow into the river and suppressing the occurrence of algae.

Carbon dioxide produced from biomass is biogenic. It is considered to be neutral carbon, and is therefore excluded from calculations of greenhouse gas emissions. In Korea, methods for calculating greenhouse gas emissions are categorized into Tiers 1 to 4, according to emission activities. Emissions measured by the methods in Tiers 1 to 3 are partially excluded from total CO2 emissions according to the proportion of biomass contained in the waste. The Tier 4 method measures CO2 emissions by measuring the amount and composition of the exhaust gas. However, this method does not consider the biomass content. In Tier 4, as in Tiers 1 to 3, it is necessary to partially exclude CO2 emissions from the greenhouse gas emissions in the flue gas according to the biomass ratio. In this study, the biomass content of SRF used in domestic facilities was analyzed using SDM. In addition, the biomass content of the exhaust gas from these facilities was analyzed using AMS. It was found that SRF contains 43.6% biomass on average. Furthermore, it was confirmed that the biomass content of the SRF used in facilities measured by SDM and the biomass content of the exhaust gases measured by AMS were similar.

Various pollutants are emitted and released during cooking, smoking, cleaning, and building materials in indoor environments. Indoor air quality management in kitchens is important because a considerable amount of pollutants are produced by the high temperature and combustion conditions associated with the cooking process. In this study, the correlation between the concentration characteristics of several indoor pollutants generated during cooking, and the detected concentration of these pollutants is investigated based on the ventilation pattern. When liquefied natural gas was burned for one hour without ingredients, the levels of CO and NO2 were 6-7 times higher compared with the background concentration due to incomplete combustion. When fish was roasted, PM2.5 concentration was approximately three times higher compared with when meat was roasted. However, the level of gaseous pollutants was higher for the latter. Based on the evaluation of the ventilation effect during the operation of the range hood, the concentration of particulate and gaseous pollutants (CO, NO2) was approximately ten times lower compared with the off state. In addition, when the hood is turned off, the time taken to decrease the concentration in the pre-cooked state is five hours or more, indicating that ventilation is necessary for indoor cooking.

Distributions of 16 PAHs and 82 PCBs (including dioxin-like PCBs, DL-PCBs, and non-dioxin-like PCBs, NDL-PCBs) were investigated in sediment and seafood samples collected from the Gunsan coast, Korea. Total PAH (Σ16PAH) concentrations in sediments were in a range of 0.09~108 (mean: 57.9) ng/g-dry and gradually decreased outwardly. PAHs in marine sediments were originated from both combustion processes and petroleum sources. The total PCB (Σ82PCB) concentrations in sediments were in a range of nd (not detected)-0.64 (mean: 0.27) ng/g-dry, and DL-PCB (Σ12 dioxin-like PCB) were in a range of nd-0.293 (mean 0.054) pg-TEQ/g-dry. DL-PCB concentrations were correlated with NDL-PCB concentrations. In this study, the concentrations of PAHs and PCBs in marine sediments did not exceed the ecotoxicological values. Total PAH concentrations ranged from nd to 24.3 (mean: 5.35) ng/g-wet, benzo[a]pyrene (BaP) was not detected in seafood samples and the concentrations of Σ4PAH (BaP, chrysene, benzo[a]anthracene, and benzo[b]fluoranthene; nd-18.5 ng/g-wet) were lower than the maximum level (30 ng/g-wet) set by EU. The concentrations of NDL-PCBs in seafood samples were in a range of nd-0.19 (mean: 0.08) ng/g-wet less than 1% of the EU-set maximum level. The DL-PCB concentrations were below 0.1 pg-TEQ/g-wet, less than 1% of the EU-set maximum level. Human risk assessment of PAHs and PCBs via seafood consumption was carried out, and both lifetime cancer risk and non-cancer risk were low.

In this study, methods of extraction, purification, and instrumental analysis are validated for 16 types of polycyclic aromatic hydrocarbons (PAHs) defined by the United States Environmental Protection Agency (US EPA), to analyze their occurrence during cooking in residential environments. Accelerated solvent extraction (ASE), which is more efficient than other extraction methods, are used and the recovery rate of gaseous samples (excluding NaP) and particulate samples was 80-110% with a relative standard deviation (RSD) of 0.6-19.8%. The purification method was compared with the column and the cartridge purification, with recovery rates of 80-110% and 60-100%, respectively. Through this process, a high recovery rate of the 16 substances was confirmed by the column purification method after ASE. The rate was 78-102% (RSD: 0.3-10%) for the gas samples and 73.7-101.7% (RSD: 0.7-20%) for particulate samples, respectively. The recovery rate of the analytical method used in this study was 66.6-80.2% (RSD: 4.7-8.3%) in the gas phase samples and 72.5-97% (RSD: 5.1-10.1%) in the particulate samples. As a result, it seems reasonable to apply the analytical method proposed in this study to real sample analyses.