Eriko Yamazaki

Bisphenol A and other bisphenol analogues including BPS and BPF in surface water samples from Japan, China, Korea and India.

Concentrations of eight bisphenol analogues (BPs) including BPA, BPS, and BPF were determined in surface waters collected from select rivers in Japan, Korea, China, and India. BPA was found at a concentration in the range of several tens to several hundreds of nanograms per liter in most of the rivers surveyed and some of the highest concentrations (54-1950 ng/L) were found in rivers in Chennai, India. Concentrations of BPF were one to two orders of magnitude higher than those of BPA in river and sea waters collected from Japan, Korea and China, which suggested that BPF is a major contaminant in surface waters in several Southeast Asian countries. BPF concentrations as high as 2850 ng/L were found in the Tamagawa River in Japan. The flux of BPs through riverine discharges into Tokyo Bay was calculated to be approximately 5.5 t per year. Based on the flux estimates and the mass of BPF found in water column and sediment in Tokyo Bay, it was found that BPF degrades faster than BPA in the environment. Elevated concentrations of BPF found in surface waters suggest the need for further studies to determine the fate and toxicity of this compound.

Transport of perfluoroalkyl substances (PFAS) from an arctic glacier to downstream locations: implications for sources.

Perfluoroalkyl substances (PFAS) have been globally detected in various environmental matrices, yet their fate and transport to the Arctic is still unclear, especially for the European Arctic. In this study, concentrations of 17 PFAS were quantified in two ice cores (n=26), surface snow (n=9) and surface water samples (n=14) collected along a spatial gradient in Svalbard, Norway. Concentrations of selected ions (Na(+), SO4(2-), etc.) were also determined for tracing the origins and sources of PFAS. Perfluorobutanoate (PFBA), perfluorooctanoate (PFOA) and perfluorononanoate (PFNA) were the dominant compounds found in ice core samples. Taking PFOA, PFNA and perfluorooctane-sulfonate (PFOS) as examples, higher concentrations were detected in the middle layers of the ice cores representing the period of 1997-2000. Lower concentrations of C8-C12 perfluorocarboxylates (PFCAs) were detected in comparison with concentrations measured previously in an ice core from the Canadian Arctic, indicating that contamination levels in the European Arctic are lower. Average PFAS concentrations were found to be lower in surface snow and melted glacier water samples, while increased concentrations were observed in river water downstream near the coastal area. Perfluorohexanesulfonate (PFHxS) was detected in the downstream locations, but not in the glacier, suggesting existence of local sources of this compound. Long-range atmospheric transport of PFAS was the major deposition pathway for the glaciers, while local sources (e.g., skiing activities) were identified in the downstream locations.

The environmental photolysis of perfluorooctanesulfonate, perfluorooctanoate, and related fluorochemicals

A field study on the photolysis of perfluoroalkyl substances (PFASs) was conducted at high altitudes in Mt. Mauna Kea (Hawaii, USA; 4200 m) and Mt. Tateyama (Toyama, Japan; 2500 m). Results of photolysis of PFASs in the field were further confirmed in laboratory studies. Perfluorooctanesulfonate (PFOS), which is perceived as a non-degradable chemical in the environment, can undergo photolysis. Long chain PFASs can be successively dealkylated to short chain compounds such as perfluorobutyric acid (PFBA) and perfluorobutane sulfonate (PFBS), but the short chain compounds were relatively more resistant to photodegradation. These results suggest that environmental levels of short chain PFASs would increase both due to their formation from photolysis of long chain PFASs and from direct releases. Earlier studies on photolysis of PFASs were focused on the formation of perfluorocarboxylic acids (PFCAs) and perfluorosulfonic acids (PFSAs) from precursor compounds (such as fluorotelomer alcohols) under laboratory conditions. Our study suggests that PFSAs and PFCAs themselves can undergo photodegradation in the environment.

Distribution and primary source analysis of per- and poly-fluoroalkyl substances with different chain lengths in surface and groundwater in two cities, North China.

Per- and poly-fluoroalkyl substances (PFASs) have been widely detected in the hydrosphere. The knowledge on the distribution and composition patterns of PFAS analogues with different chain length significantly contribute to their source analysis. In the present study, a regional scale investigation of PFASs in surface river waters and adjacent ground waters was carried out in two cities of China with potential contamination, Tianjin and Weifang. A total of 31 water samples were collected, and 20 PFASs therein were measured by a high-performance liquid chromatograph-tandem mass spectrometer (HPLC-MS/MS). The possible sources of PFASs in the aquatic environment were assessed primarily by concentration patterns as well as hierarchical cluster analysis. In all 4 rivers investigated in the two cities, perfluoroalkyl carboxylic acids (PFCAs) were the dominant compounds contributing over 70% of the PFASs detected. Perfluorooctanoic acid (PFOA) was the dominant PFCA with a concentration range of 8.58-20.3ng/L in Tianjin and 6.37-25.9ng/L in Weifang, respectively. On the average, the highest concentration was observed in samples from Dagu Drainage Canal (Dagu) in Tianjin and those short-chain PFASs (C4-C6) was detected with a comparable level of the longer-chain PFASs (>C6). Specifically, perfluorobutanoic acid (PFBA) was dominant in the short-chain analogues. This indicates that a remarkably increasing input of short-chain PFASs might be related to wastewater treatment plant effluent or industrial discharges, which could be possibly due to the switch of manufacturing to short-chain products. In Weifang, precipitation and subsequent surface runoff as non-point sources could be significant inputs of PFASs into surface water while groundwater was possibly subjected to severe point sources with ∑PFASs concentration up to ~100ng/L. The inconsistent distribution patterns in groundwater suggest complicated pathways of contamination.

Perfluorinated carboxylic and sulphonic acids in surface water media from the regions of Tibetan Plateau: Indirect evidence on photochemical degradation?

ABSTRACT Perfluorinated surfactants and repellents are synthetic substances that have found numerous industrial and customer applications. Due to their persistence, at least two groups of these substances—perfluorinated carboxylic acids (PFCAs) and perfluorinated sulfonic acids (PFSAs)—are diffused widely in the environment. It is hypothesized that the Tibetan Plateau, is one of few unique places on the Earth, due to its topography, specifically the vast space and high elevation above sea level, geographic location, climate, high solar radiation, lack of industry, little urbanization and general lack of significant direct sources of pollution. There it is believed possible to gain an insight into atmospheric fate (possible photochemical degradation of higher molecular mass and formation of lower molecular mass PFCAs and PFSAs) of PFASs under un-disturbed environmental conditions. Ultratrace analytical method for PFCAs and PFSAs and use of transportation and field blanks, laboratory blanks and isotopically labelled surrogates for recovery control has allowed the determination of nine perfluorinated carboxylic acids and six perfluorinated sulfonic acids at ultra-trace levels in water based samples from the alpine dimension regions of the Tibetan Plateau, the eastern slope of Minya Konka peak at the eastern edge of the Tibetan Plateau, and also from the city of Chengdu from the lowland of the Sichuan Province in China. The specific compositional pattern of PFCAs and PFSAs and low levels of pollution with those compounds were observed in the central region of the Tibetan Plateau and in the region adjacent to the peaks of Minya Konka in the Eastern Tibetan Plateau. The fingerprint of the compositional pattern of PFCAs and PFSAs in water samples in the central region of the Tibetan Plateau and in the alpine region adjacent to the peaks of Minya Konka in the Eastern Tibetan Plateau may be explained by the result of photochemical degradation with dealkylation of longer chain compounds and formation of shorter chain compounds, which are more resistant to photochemical degradation.

Microminipigs as a new experimental animal model for toxicological studies: comparative pharmacokinetics of perfluoroalkyl acids

In this study, we evaluated the efficacy of a novel minipig strain, the Microminipig (MMPig), as an animal model for studying the pharmacokinetics of a mixture of 10 perfluoroalkyl acids (PFAAs). After a single oral dose was given, we found that the blood depuration of PFAAs (blood t1/2), which we calculated using first‐order elimination curves, ranged from 1.6 to 86.6 days. Among the five body compartments analyzed, the liver was the greatest site of accumulation of perfluorooctanesulfonate and longer chain perfluorinated carboxylates such as perfluorodecanoic acid, perfluoroundecanoic acid and perfluorododecanoic acid. We observed an increasing accumulation trend of perfluorinated carboxylates in the organs associated with the fluorinated carbon chain length. The perfluorononanoic acid burden was the highest among the treated compounds 21 days after a single exposure, as 29% of the given perfluorononanoic acid dose was accumulated in the tissues. The persistence of PFAAs in edible pig tissues even after 21 days post‐exposure raises concerns about the safety of swine products. This was the first study to use MMPigs to elucidate the pharmacokinetics of a group of environmental pollutants. We found that MMPigs could be excellent experimental animals for toxicological studies due to their easy handling, cost efficacy for target compounds and ease of waste treatment. Copyright

Emission, Dynamics and Transport of Perfluoroalkyl Substances from Land to Ocean by the Great East Japan Earthquake in 2011.

Water samples collected along the Japanese coast and in the open Pacific Ocean in 2010, 2011, and 2012 were analyzed for perfluoroalkyl substances (PFASs) to evaluate the effect of Great East Japan Earthquake (EQ 3.11), which occurred on March 11, 2011, on the dispersion of chemical pollutants. Ultratrace analysis of PFASs in water, a super computer simulation, and an inventory analysis from industrial records revealed the sources and dynamics of PFASs during the EQ 3.11 disaster. In this respect, EQ 3.11 destroyed solid infrastructure on land, and within minutes, PFASs stocked therein were released into the open environment. The historically significant tsunami backwash swept them away from their origin to the coastal water within several hours. It was estimated that from 0.8 to 1.0 tons of perfluorooctanesulfonate (PFOS) and 4.8 to 5.1 tons of PFOA were discharged into the coastal waters after EQ 3.11 and the tsunami that followed. The reconstruction of EQ 3.11 also traced the influence of this pollution in open ocean water until March 2012, and a statistical and finger printing analysis revealed that there were different distribution mechanisms in coastal regions than in the open ocean for PFOS, other shorter chain perfluorinated sulfonic acids and perfluorinated carboxylic acids.

Oceanic dispersion simulation of perfluoroalkyl substances in the Western North Pacific associated with the Great East Japan Earthquake of 2011

The Great East Japan Earthquake on 11 March 2011, followed by the tsunami and fire, resulted in serious environmental problems in and around Japan. A huge amount of material was discharged into the ocean after the tremendous flood damage of the tsunami. A monitoring survey of the perfluoroalkyl substances (PFAs) found evidence showing an abrupt increase in the PFA concentration in the ocean east of Japan in 2011 after the earthquake. To confirm the anomalous input of two typical PFAs, perfluorooctanoate (PFOA) and perfluorooctanesulfonate (PFOS), from the Japanese coast into the ocean, associated with the earthquake, we conducted a series of chemical tracer simulations using an eddy-resolving ocean reanalysis product: JCOPE2. The simulation model involves processes representing the emission of PFAs from the land triggered by the tsunami flood, advection of the polluted waters, and decay of the concentration by the background oceanic turbulence. Comparison of the PFOA simulation results with the observation confirms a spike-like input of PFOA into the Western North Pacific after the earthquake. Advection and diffusion by the Kuroshio Extension and the mesoscale eddies play a key role in the dilution of the concentration. Optimization of unknown simulation parameters leads to an estimation of the total amount of the anomalous PFOA emission. In contrast, the PFOS simulations are not able to explain the observed distribution, suggesting possible differences in the oceanic transport processes between PFOS and PFOA.

Accumulation of quaternary ammonium compounds as emerging contaminants in sediments collected from the Pearl River Estuary, China and Tokyo Bay, Japan

In this work, the distribution of quaternary ammonium compounds (QACs) in two dated sediment cores, collected from the Pearl River Estuary (PRE) and Tokyo Bay (TB), were investigated to understand the historical input of QACs and their diagenetic behavior in urban estuarine environments. The vertical variation profiles of QAC concentrations showed that benzylalkyldimethyl ammonium compounds (BACs) and dialkyldimethyl ammonium compounds (DADMACs) were widely used during 1970s and 1980s both in China and Japan. The declining environmental concentrations of QACs suggested a compositional change of commodities and the effectiveness of emission control strategies. For the individual QAC homologues, BAC homologues decreased significantly over time, while DADMAC compositions remained relatively stable. The differences in concentration and composition profiles of BACs and DADMACs in the sediment cores provided useful information on the patterns of use of QACs in China and Japan, as well as their diagenetic behaviors in the sediments.