Mercury monitoring in the coastal areas of the Republic of Korea using the black-tailed gull egg as an indicator.

In the southeast and east coasts of the Republic of Korea, it is essential to monitor mercury accumulation in coastal organisms in view of the higher mercury distribution in sediments and human samples. However, mercury pollution monitoring in organisms, especially higher trophic-level organisms that can exhibit high mercury accumulation, is limited. Here, we examined the applicability of the eggs of the black-tailed gull (Larus crassirostris), which belongs to a high trophic level, for mercury monitoring in coastal areas. Breeding sites were selected in West, Southeast, and East Seas with different mercury concentrations in other matrices (sediment and biological samples of residents). The 5-year mean total mercury concentration in eggs collected during the breeding seasons from 2016 to 2020 was lower in Baengnyeongdo (705 ± 81 ng/g dry weight (dry), West Sea) than in Hongdo (1,207 ± 214 ng/g dry, Southeast Sea) and Ulleungdo (1,095 ± 95 ng/g dry, East Sea). The different patterns of mercury concentration in gull eggs among the breeding sites was consistent with those in the other matrices among the coastal areas. These results support the applicability of the black-tailed gull egg as an indicator for establishing a monitoring framework in the coastal areas of the Republic of Korea.

Per- and polyfluoroalkyl substances and their alternatives in black-tailed gull (Larus crassirostris) eggs from South Korea islands during 2012-2018.

The temporal and spatial trends of sixteen per- and polyfluoroalkyl substances (PFAS) and their three alternatives, chlorinated polyfluoroalkyl ether sulfonic acid (F-53B), hexafluoropropylene oxide dimer acid (GenX), and dodecafluoro-3H-4,8-dioxanonanoate (ADONA) in whole eggs of black-tailed gulls from two South Korean islands, Baengnyeongdo (BLD) and Hongdo (HD), were investigated during 2012-2018. A total of 16 analyzed compounds were detected at concentrations of 21.3-47.8 ng/g ww in BLD and 11.2-40.0 ng/g ww in HD. Meanwhile, the mean levels of perfluorooctanesulfonic acid (PFOS) and perfluorooctanoic acid (PFOA) were detected at 6.92 ± 4.72 ng/g ww and 0.674 ± 0.993 ng/g ww, respectively. In particular, F-53B, a major alternative to PFOS was detected in each year of the study period with a level of up to 6.66 ng/g ww in all egg samples. Significant increasing temporal trends were observed for PFOS, perfluorononanoic acid (PFNA) and one alternative (F-53B) during the investigated period suggesting continuous use or accumulation of these in the Korean environment. Moreover, distinctive spatial distribution patterns such as a significantly higher F-53B level in HD and an increased PFAS (< C11) in BLD were also observed.

Occurrence, Removal, and Environmental Emission of Organophosphate Flame Retardants/Plasticizers in a Wastewater Treatment Plant in New York State.

The occurrence and fate of 14 triester organophosphate flame retardants (OPFRs) and plasticizers and their two diester metabolites were investigated in a wastewater treatment plant (WWTP) in the Albany area of New York State. All target OPFRs were found in wastewater, with average concentrations that ranged from 20.1 ng/L for tris(methylphenyl) phosphate (TMPP) to 30 100 ng/L for tris(2-butoxyethyl)phosphate (TBOEP) in influents and from 7.68 ng/L for TMPP to 12 600 ng/L for TBOEP in final effluents. TBOEP was the dominant compound in influents (max: 69 500 ng/L) followed in decreasing order by tris(1-chloro-2-propyl)phosphate (TCIPP; max: 14 500 ng/L), bis(1,3-dichloro-2-propyl)phosphate (BDCIPP; max: 4550 ng/L), tris(1,3-dichloro-2-propyl)phosphate (TDCIPP; max: 3150 ng/L) and tris(2-chloroethyl)phosphate (TCEP; max: 8450 ng/L). The fraction of TMPP sorbed to suspended particulate matter (SPM) was 56.4% of the total mass in wastewater, which was the highest among the target chemicals analyzed. The average concentrations of OPFRs in sludge were between 4.14 ng/g dw for tripropyl phosphate (TPP) and 7290 ng/g dw for TBOEP; for ash, they were between 2.17 ng/g dw for TMPP and 427 ng/g dw for triphenyl phosphate (TPhP). The mass loadings of OPFRs into the WWTP ranged from 0.02 mg/day/person for TPP to 28.7 mg/day/person for TBOEP, whereas the emission from the WWTP ranged from 0.01 mg/day/person for 2-ethylhexyl diphenyl phosphate (EHDPP) to 5.12 mg/day/person for TCIPP. The removal efficiencies for OPFRs were slightly above 60% for TMPP, TBOEP, and tris(2-ethylhexyl)phosphate (TEHP) whereas those for other OPFRs were <40% (TPhP and BDCIPP) to negative values, suggesting incomplete removal in WWTPs.

Levels and distribution of hexabromocyclododecane and its lower brominated derivative in Japanese riverine environment.

Hexabromocyclododecane (HBCD) and its lower brominated derivatives were measured in both surface water and sediment samples from three Japanese rivers; Tsurumi River, Yodo River, and Kuzuryu River. The concentration level of ∑HBCD (sum of α-, ß-, and γ-HBCD) was in the order of Kuzuryu>Yodo>Tsurumi Rivers, reflective of the different emission sources for each basin. The highest ∑HBCD concentration (7800 ng g(-1)dw) was detected in the sediment sample from the Kuzuryu River that receives effluents from textile industries, which use HBCD in flame retardant finishes. A different diastereomeric pattern of α-, ß-, and γ-HBCD of each river was investigated, indicating the level of HBCD in these rivers is directly influenced by emission source. Enantiomer fractions of HBCDs in water and sediment samples were also determined. Racemic mixtures were observed in the water samples, whereas enantiomeric enrichment of (-) γ-HBCD and (+) α-HBCD was observed in the sediment samples. Some lower brominated HBCD derivatives such as pentabromocyclododecenes were detected in both the water and sediment samples, and their concentration ranged from below the detection limit to 15 ng L(-1) and 20 ng g(-1)dw, respectively.