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-To examine the kinetics of low doses of perfluoro compounds (PFCs), we administered perfluorohexanoic acid (C6A), perfluorooctanoic acid (C8A), perfluorononanoic acid (C9A) and perfluorooctane sulfonate (C8S) with a single oral dose (50-100 μg/kg BW), and in drinking water at 1, 5, and 25 μg/L for one and three months to male rats; and examined the distribution in the brain, heart, liver, spleen, kidney, whole blood and serum. C6A was very rapidly absorbed, distributed and eliminated from the tissues with nearly the same tissue t 1/2 of 2-3 hr. Considering serum Vd, and the tissue delivery, C6A was mainly in the serum with the lowest delivery to the brain; and no tissue accumulation was observed in the chronic studies as estimated from the single dose study. For the other PFCs, the body seemed to be an assortment of independent one-compartments with a longer elimination t 1/2 for the liver than the serum. The concentration ratio of liver/serum increased gradually from C 0 to a steady state. The high binding capacity of plasma protein may be the reason for the unusual kinetics, with only a very small fraction of free PFCs moving gradually to the liver. Although the tissue specific distribution was time dependent and different among the PFCs, the Vd and k e of each tissue were constant throughout the study. The possibility of extremely high C6A accumulation in the human brain and liver was suggested, by comparing the steady state tissue concentration of this study with the human data reported by Pérez et al. (2013).

Perfluorinated compounds (PFCs) have been used widely, detected worldwide in the environment, and have accumulated highly in animals. As far as we know, there have been no reports which relate the PFC concentration in wild animals to the physicochemical properties. Therefore, we measured the concentrations of 15 currently available PFCs (perfluorocarboxylic acids with x carbons: Cx, perfluorosulfonic acids with x carbons: CxS) in medaka and the environmental water where medaka live. Samples were obtained from 7 points in Japan (Iwate, Ibaraki, Niigata, Hyogo, Yamaguchi, Ehime, and Nagasaki) from July to September in 2013. Twenty to forty medaka were collected from each point, as well as 2 L of water in a clean PET bottle. PFCs were extracted and concentrated using a solid-phase cartridge, and were measured by LC/MS/MS. The medaka samples were treated individually. C5-C9 and C8S were detected mainly in the water, C11-C13 and C8S were detected mainly in medaka. C8S was always detected in high concentrations in the water and medaka. The bioconcentration factors (BCFs) of PFCs were calculated from PFC concentrations of the water and the medaka. The BCFs of C8-C11 were increased exponentially with the length of carbon chain. The BCF of C8S (approx. 5,500) was far greater than C8 (approx. 330) or C9 (approx. 480). However, the BCFs of C8-C11 and C8S tended to increase in proportion with octanol/water partition coefficient (log K ow).

With the increasing number and volume of chemicals used in modern life, their adverse effects on human health and aquatic organisms have increased concerns as well. To formulate appropriate management plans, the amounts/ volumes used and emitted of these chemicals must be regulated. However, no data are available on the use of most chemicals, particularly daily-use chemicals such as pharmaceuticals and personal care products (PPCPs). Herein, we tested eight activated sludge wastewater treatment plants (WWTPs) across Japan, each servicing populations of over 200,000, to investigate the emissions of 484 chemicals including 162 PPCPs. Twenty-four-hour composite samples were collected before and after the activated sludge component of treatment in each season of 2017. Targeted substances were solid-phase extracted and subsequently measured by LC-QTOF-MS-Sequential Window Acquisition of All Theoretical Fragment-Ion Spectra Acquisition. The mean number of the detected substances and their mean total concentrations in inflows (n = 32) and outflows (n = 32) were 87 and 92 and 108,517 and 31,537 ng L − 1 , respectively. Pharmaceuticals comprised 50% of the screened chemicals in the inflow. The median removal efficiency was 31.3%: 29.2% for pharmaceuticals and 20.2% for pesticides, which were similar to those in the literature. Cluster analysis showed that spatial differences among the WWTPs are larger than seasonal differences in the same WWTP. Regardless, we detected seasonal differences in the amounts of substances in the inflows: the amounts of sucralose, UV-filters, and insecticides were larger in summer than in winter, whereas those of ibuprofen and chlorpheniramine were larger in winter than in summer. The total inflow and outflow population equivalent loads estimated using wastewater volume, detected concentrations, and populations were 44.7 and 13.0 g 1,000 capita − 1 d − 1 , respectively. The extrapolated total annual Japan-wide inflow and outflow loads were 2,079 and 671 tons y − 1 , respectively. Using the data obtained in this study, we identified 13 candidates of marker substances for estimating real-time population in a sewage treatment area and 22 candidates of marker substances for sewage contamination.

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