An analytical method for monitoring 10 phthalic acid monoesters in river water was investigated by solid-phase extraction, methylation with diazomethane, and GC-MS. Two cartridge-type solid phases packed with octadesyl-coated silica (C18) and styrenedivinyl polymer (PS-2) and one disk-type solid phase made from octadesyl-coated styrenedivinylbenzene polymer (SDB-XD) were investigated in solid-phase extraction. PS-2 gave the highest recoveries of the three solid phases, and recoveries of more than 80% of the monoesters in filtered water samples were obtained at pH 2 to 3 with PS-2 at the spiked level of 0.1 microg L(-1), except for monomethyl-phthalate (MMP), in which more than 72% of the monoesters were recovered. For the monoesters in the suspended solids (SS), an acidic methanol extract of SS was added to purified water acidified to pH 2, and the monoesters were extracted with PS-2. The recoveries of the monoesters in SS were more than 80%, but the recoveries of MMP were more than 57%. The method detection limit (MDL) of each phthalic acid monoester in 500 mL of water sample and in 2 mg of dry weight of SS ranged from 0.010 to 0.030 microg L(-1) and from 1 to 11 microg g(-1), respectively. Monitoring of phthalic acid monoesters in the Tama River in Tokyo was conducted every month from March 1999 to February 2000 using the present method. MMP, mono-n-butyl-phthalate (MBP), and mono-(2-ethylhexyl)-phthalate (MEHP) were detected at concentrations of 0.030-0.0340, 0.010-0.480, and 0.010-1.30 microg L(-1), respectively, in the filtered water samples but were not detected in SS. Dimethyl-phthalate (DMP), di-n-butyl-phthalate (DBP), and di-(2-ethylhexyl)-phthalate (DEHP) were detected in the river water at concentrations of 0.010-0.092, 0.008-0.540, and 0.013-3.60 microg L(-1), respectively. Diethyl-, di-iso-butyl-, and benzylbutyl-phthalates were also detected at concentrations of nanograms per liter, whereas the corresponding monoesters did not appear. The concentrations of MBP and MEHP in the river water were slightly lower than those of the corresponding diesters at the majority of sampling sites and sampling times.
Monitoring of bisphenol A [BPA; 2,2-bis(4-hydroxyphenyl)propane] and its biological metabolites [4,4'-dihydroxy-alphamethylstilbene (DHMS), 2,2-bis(4-hydroxyphenyl)-1-propanol (BPA-OH), 2,2-bis(4-hydroxyphenyl)propanoic acid (BPA-COOH), and 2-(3,4-dihydroxyphenyl)-2-(4-hydroxyphenyl)propane (3-OH-BPA)] in river waters was performed by solid-phase extraction and GC/MS determination. The concentrations of BPA, BPA-COOH, BPA-OH, and 3-OH-BPA in the river water ranged from 2 to 230 (8.8 x 10(-12) to 1.0 x 10(-9) M), from 5 to 75 (1.9 x 10(-11) to 2.9 x 10(-10) M), from 3 to 16 (1.2 x 10(-11) to 6.6 x 10(-11) M), and from 3 to 11 (1.2 x 10(-11) to 4.5 x 10(-11) M) ng L(-1), respectively. DHMS, an intermediate in the main degradation pathway of BPA, was not detected in any water sample. Under the aerobic conditions in the river water, BPA disappeared within 8 d of incubation, but BPA-COOH, BPA-OH, and tetraol remained in the supernatant after 14 d of incubation. For the xeno-estrogenic activity of BPA and the metabolites, their ability to bind to recombinant human estrogen receptor alpha in competition with fluorescence-labeled 17beta-estradiol was measured. Fifty percent inhibitory concentrations (IC50) of BPA, DHMS, 3-OH-BPA, and BPA-OH were approximately 1 x 10(-5), 1 x 10(-6), 3 x 10(-5), and 1 x 10(-2) M, respectively. In human cultured MCF-7 breast cancer cells, BPA increased cell numbers in a dose-dependent manner at concentrations from 10(-7) to 10(-5) M. For the BPA metabolites, DOHMS, 3-OH-BPA, and BPA-COOH caused the cells proliferation at concentrations from 10(-9) to 10(-6), from 10(-7) to 10(-6), and from 10(-5) to 10(-4) M, respectively. BPA-OH did not cause MCF-7 cells proliferation. These results indicate that BPA is mainly metabolized through oxidative rearrangement by bacteria in the river water, and intermediate bisphenols via minor metabolic pathways exist in river water. The presence of the bisphenols having the xeno-estrogenic effect suggests the necessity of monitoring those in river water, in the effluent waters from sewage plants, or in landfill leachate.
Pollution from 35 perfluorinated compounds (PFCs) in the water of the Tokyo Bay basin was examined. The water in the basin contained relatively high levels of perfluorononanoate (PFNA), perfluorooctanoate (PFOA), and perfluorooctane sulfonate (PFOS) compared to the other PFCs, which were present at concentrations of 20.1 ng/L, 6.7 ng/L, and 5.8 ng/L, respectively. In contrast, the concentrations of their precursors and degradation products were an order of magnitude lower. Sewage treatment plant (STP) effluent in the area also contained high levels of PFNA compared with the river water samples (Mann-Whitney U-test, p<0.0002). From a spatial aspect, increases in PFC pollution levels correlated with increased urbanization in the study area suggested that there are nonpoint source contributors to the PFC pollution in this area. Branched isomers of the PFCs were also quantified. Samples that contained high concentrations of perfluoroalkyl carboxylates (PFCA) showed lower proportions of its branched isomer. This indicates that the branched isomers are more prominent in the area with lower PFC pollution. This analysis was beneficial for estimating the individual contributions of different PFCA production processes. This survey provided new information on the sources, spatial distribution, and behavioral characteristics of PFC pollutants in this area.
The monitoring of 19 pesticides in drainage and groundwater at a golf course was performed when there was no runoff water. The loading rates of most pesticides via leaching water were lower than 4% of application amount, except for more than 23% for terbutol. The times of pesticides loading into the drainage reducing to 50% of initial [t 1 /2(loading)] were 40.3 months for terbutol, 9.4 months for isoprothiolane, 6.6 months for flutolanil, and within 1 month for the other pesticides. On the basis of several published models for predicting pesticides leaching to groundwater at agricultural land, the pesticides having the GUS score greater than 0.4 or exhibiting K oc less than 7000 cm3 g-1, and t 1 /2(soil) greater than 3 days were classified as the pesticides leaching to groundwater at golf courses. The golf course is a high pollution potential area compared with agricultural land. For the persistence of terbutol at golf courses, the concentrations of terbutol in subsoils at the depth greater than 50 cm were higher than the other pesticides after 4 years when terbutol was applied. The half-life [t 1 /2(soil)] of terbutol, isoprothiolane, and fltutoranil in the turf grass soils under an aerobic condition was 200, 180, and 360 days, respectively. Organic carbon partition coefficient (K oc) and relative mobility in the soil column of terbutol were the same as isoprothiolane and flutoranil. These results suggested that persistence of terbutol was mainly caused by slow degradation rate in the subsoils.
Cadmium was injected sc into female Wistar rats at a dose of 3.0 mg Cd/kg body weight, 4 times a week for 1, 2, 3, 4, 5, and 6 wk. Cadmium and five essential metals in the livers and kidneys were determined simultaneously by inductively coupled plasma-atomic emission spectrometry. Concentration of cadmium in the livers increased linearly up to 3 wk, remained at an almost constant and highest value (440 micrograms Cd/g wet liver) for the following 2 wk, and then decreased. The difference between cadmium in the whole livers and cadmium bound to heat-stable proteins was wider during the plateau than during the other periods. Cadmium in the kidneys was close to a plateau after 6 wk of injections. Concentrations of zinc in the livers and copper in the kidneys changed dramatically with injections of cadmium, and the changes were related to the changes in concentrations of the two metals in plasma and urine. Concentration of iron in the kidneys decreased with injections of cadmium. The content ratio of calcium to magnesium was high in the case of liver edema and was suggested to be an indicator. Cadmium in urine was assumed to originate from the liver in the case of high accumulation of the metal.
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