Concentrations of 10 perfluorinated compounds in water and fish from rivers and lakes in the world were reviewed from the surveys in the years of 1998-2011. A yearly decreasing tendency was recognized in the concentrations of Perfluorooctane sulfonate (PFOS) and Perfluorooctanoic acid (PFOA) in water from several rivers in Japan. The concentrations of PFOA in water from rivers and lakes in Japan had a tendency to be higher than those of PFOS but the concentration levels of both compounds were equal in Europe. Further, the concentrations of PFOS in water from rivers in Europe and North America were higher than those in Japan and Asia. Composition of the perfluorinated compounds was PFOA >> Perfluorononanoic acid (PFNA) ≧ Perfluorohexanoic acid (PFHxA) in water from rivers and lakes in Japan and PFOS ≧ PFOA in Asia, Europe and North America. Perfluorinated compounds with more carbon atoms were more highly accumulated in fish, and bioconcentration factor (BCF) of PFOS was lower than that of Perfluorododecanoic acid (PFDDA) and nearly equal to that of Perfluoroundecanoic acid (PFUA) or Perflurorodecanoic acid (PFDA). Each of the BCF data of the perfluorinated compounds by field survey data (Field BCF) was nearly in the same order as each of the BCF data by laboratory experimental data (Laboratory BCF). However, absolute values of the Field BCF had a tendency to be higher than those of the Laboratory BCF. To verify this tendency, it is necessary to accumulate additional data on Laboratory and Field BCF and to advance the research development in future on adding the uptake of the compounds via food for the uptake of the compounds via gill in the Field BCF values or on the differences of the environmental conditions.

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Magnetite-iron from spent pocket warmers was recovered and coated with chitosan that was modified with 2-oxoglutaric acid. This material was used to remove toxic Pb²⁺ from aqueous solution. The prepared adsorbents were characterized by SEM, XRD, IR, and ionic dye adsorption experiments. Adsorption of Pb²⁺ depended on the composition of the iron (magnetite or unoxidized iron) from the pocket warmer and impurities, such as charcoal and vermiculite. For samples with a high magnetite content, adsorption of Pb²⁺ was good. When 0.5 g of the present adsorbent was used in the treatment for 50 mL solution containing 10 mg/L of Pb²⁺ , the removal efficiency more than 99% was achieved to reduce to 0.1 mg/L. The adsorption ability of Pb²⁺ was compared with that of an activated carbon. The adsorbent was applied to the removal of Pb²⁺ from wastewater of a Pb-acid battery.

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Levofloxacin (LVFX) is a potent synthetic antibacterial agent of the third-generation fluoroquinolones (FQs) that inhibits the bacterial enzymes DNA gyrase and topoisomerase IV. Because of its extensive usage, LVFX may enter the water environment through wastewater effluent.
In the present study, to verify the effects of LVFX on aquatic life by chlorination which is used in the disinfection process of sewage treatment, an evaluation using the algal growth inhibition test was conducted. In addition, scan data and fragmentation patterns were acquired by liquid chromatography/tandem mass spectrometry (LC/MS/MS) to clarify the change of chemical structure of LVFX caused by chlorination.
The results of the algal growth inhibition test showed that the Toxicity Unit (TU) of the chlorinated sample was 1600 times higher than the hazard quotient (HQ) for the amount of LVFX in the chlorinated sample. From scan data, m/z 362 (P362), which was presumed to be the unaltered substance (LVFX), and m/z 336 (D336) and m/z 279 (D279), which were presumed to be byproducts of LVFX, were detected as the protonated molecules [M+H] ⁺ . It was conjectured that D336 and D279 had been caused by the chlorination which changed the chemical structure of position 10 of LVFX, the N′-methyl- piperazinyl group. The toxicity of the chlorinated sample may have been caused by substances other than LVFX such as chlorinated byproducts.

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Dioxins (polychlorinated dibenzo-p-dioxins, polychlorinated dibenzofurans, and dioxin-like polychlorinated biphenyls) in ash residue taken from 59 small-sized incinerators placed at facilities such as schools in Saitama prefecture, which had not been used since 1997, were determined. The range of dioxin toxic equivalent (TEQ) was 0.0019-18 ng-TEQ/g, and TEQ of dioxins in 10 of 59 ash samples exceeded the landfill standard (3 ng-TEQ/g).

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Twenty-six carcinogenic primary aromatic amines (PAAs) originating from azo dyes in commercial textile products that can potentially come into direct contact with human skin (31 products; 41 samples) and in leather products (23 products; 23 samples) in Japan were investigated. Twelve and 11 PAAs were detected in the textile and leather products, respectively, nearly all at low concentrations (below 1.0 μg/g). However, the concentrations of benzidine (45-593 μg/g) in one shawl and six sheets and covers (seven samples) exceeded European Union (EU) regulatory limits (below 30 μg/g). Concentrations of o-toluidine (430 μg/g), benzidine (31 μg/g), and 3,3′-dimethylbenzidine (40 μg/g) in leather products (hand-crafted leather) also exceeded EU regulatory limits. Shawls, sheets, and covers can come into direct contact with human skin. Thus, an exposure evaluation should be performed for benzidine in these products.

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Recently, two cases of contact dermatitis caused by 2-n-octyl-4-isothiazolin-3-one (OIT) used as a preservative in cooling gel-products has been reported in Japan, and one of the cases was declared a serious product accident based on the “Consumer Safety Product Act.” In this study, the concentrations of three isothiazolinone preservatives (OIT, 2-methyl- 4-isothiazolin-3-one [MIT], and 5-chloro-2-methyl-4-isothiazolin-3-one [Cl-MIT]), seven different parabens, carbendazim (MBC), and tebuconazole (Teb) in 24 cooling gel-products were investigated. OIT was detected in two samples (0.14 μg/g and 2.2 μg/g). MIT was detected in 11 samples at concentrations in the range of 0.12-115 μg/g and Cl-MIT was detected in six samples in concentrations ranging from a trace amount to 16 μg/g. The EU cosmetic limits were used to consider the risk of skin sensitization and the concentrations of MIT and Cl-MIT detected in several samples were over these limit. It is possible for the gel to cause contact dermatitis when the consumer′s weight presses on the gel-product because OIT might penetrate from the gel to the textile surface in the case of a serious product accident. Furthermore, it is possible that using the gel product for the forehead or neck has a similar risk of skin sensitization if the gel-product′s surface tears and the gel containing isothiazolinone preservative leaks out. It is advisable to replace the preservatives in cooling gel-products with non-sensitizing preservatives. All parabens were detected in the gel-products, except benzylparaben, and their concentrations were 12-696 μg/g. MBC and Teb were detected in three samples with concentrations in the ranges of 0.82-54 μg/g and 1.5-25 μg/g, respectively.

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