Thyroid disruption properties of three indoor dust chemicals tested in Silurana tropicalis tadpoles.

Indoor dust contains a multitude of industrial chemicals, and ingestion of dust is considered an important exposure route to organic contaminants. Some of these contaminants have been shown to interfere with the thyroid system, which may result in significant consequences on public health. The amphibian metamorphosis is a thyroid hormone-dependent process, which can be used as an in vivo model for studies on thyroid hormone-disrupting potency.

Partitioning of Chlorinated Paraffins (CPs) to Daphnia magna Overlaps between Restricted and in-Use Categories.

Chlorinated paraffins (CPs) are high-production volume industrial chemicals consisting of n-alkanes (with 10 to 30 carbon atoms in the chain) with chlorine content from 30 to 70% of weight. In Europe, the use of short chain chlorinated paraffins (SCCPs) has been restricted by the Stockholm Convention on POPs due to their PBT (persistent, bioaccumulative and toxic) properties. Medium (MCCPs) and long chain (LCCPs) chlorinated paraffins are used as substitution products.

A refined method for analysis of 4,4'-dicofol and 4,4'-dichlorobenzophenone.

The acaricide, dicofol, is a well-known pesticide and partly a substitute for dichlorodiphenyltrichloroethane (DDT). Only few reports on environmental occurrence and concentrations have been reported calling for improvements. Hence, an analytical method was further developed for dicofol and dichlorobenzophenone (DCBP) to enable assessments of their environmental occurrence.

Spatial distribution and bioaccumulation of polychlorinated biphenyls (PCBs) and polybrominated diphenyl ethers (PBDEs) in snails (Bellamya aeruginosa) and sediments from Taihu Lake area, China.

Taihu Lake area is one of the densest metropolitan areas in the world including diverse industrial activity. In the present study, the snail (Bellamya aeruginosa) and sediment were collected from the Taihu Lake area to investigate the contamination status, congener pattern, spatial distribution, and bioaccumulation effect of polychlorinated biphenyls (PCBs) and polybrominated diphenyl ethers (PBDEs). The samples underwent liquid extraction, lipid removal by sulfuric acid, and acidic silica gel column, and subsequently analyzed by gas chromatography-electron capture detector (GC-ECD) and gas chromatography-mass spectrometry (GC-MS).

Polybrominated diphenyl ethers (PBDEs) in mussels from cultures and natural population.

Polybrominated diphenyl ether (PBDE) mass fractions were determined in mussel samples collected from 6 locations around Thermaikos Gulf in north Greece. PBDEs were present in all sampling sites and the average total (ΣPBDEs) ranged from 17.7 to 32.

Extensive organohalogen contamination in wildlife from a site in the Yangtze River Delta.

The environmental and human health concerns for organohalogen contaminants (OHCs) extend beyond the 23 persistent organic pollutants (POPs) regulated by the Stockholm Convention. The current, intense industrial production and use of chemicals in China and their bioaccumulation makes Chinese wildlife highly suitable for the assessment of legacy, novel and emerging environmental pollutants. In the present study, six species of amphibians, fish and birds were sampled from paddy fields in the Yangtze River Delta (YRD) were screened for OHCs.

An Oxofluoride Catalyst Comprised of Transition Metals and a Metalloid for Application in Water Oxidation.

The application of the recently discovered oxofluoride solid solution (Cox Ni1-x )3 Sb4 O6 F6 as a catalyst for water oxidation is demonstrated. The phase exhibits a cubic arrangement of the active metal that forms oxo bridges to the metalloid with possible catalytic participation. The Co3 Sb4 O6 F6 compound proved to be capable of catalyzing 2H2 O→O2 +4H(+) +4e(-) at 0.

Higher PBDE serum concentrations may be associated with feline hyperthyroidism in Swedish cats.

Serum from 82 individual cats was analyzed for decabromobiphenyl (BB-209), polybrominated diphenyl ethers (PBDEs), hydroxylated PBDEs (OH-PBDEs), and 2,4,6-TBP in order to study differences in body burden between healthy and sick cats diagnosed with Feline Hyperthyroidism (FH). Within the study group, 60 of these cats had a euthyroid (n = 23) or hyperthyroid (n = 37) status, all of which were used in the comparison. This study shows that hyperthyroid compared to euthyroid cats have higher serum concentrations for some of the investigated PBDEs (BDE-99, BDE-153, and BDE-183) and CB-153 on a fat weight basis.

Brominated flame retardant exposure of aircraft personnel.

The use of brominated flame retardants (BFRs) such as polybrominated diphenyl ethers (PBDEs) in aircraft is the result of high fire safety demands. Personnel working in or with aircraft might therefore be exposed to several BFRs. Previous studies have reported PBDE exposure in flight attendants and in passengers.

Chlorinated and brominated organic contaminants in fish from Shanghai markets: a case study of human exposure.

In the present study were two favorite edible fish species for local residents, i.e., mandarin fish and crawfish, collected from the Shanghai market and analyzed for selected organochlorine pesticides (OCPs), polychlorinated biphenyls (PCBs), hexabromocyclododecane (HBCDD), polybrominated diphenyl ethers (PBDEs) and methoxylated PBDEs (MeO-PBDEs).

In vivo doses of acrylamide and glycidamide in humans after intake of acrylamide-rich food.

For assessment of cancer risk from acrylamide (AA) exposure through food, the relation between intake from food in humans and the in vivo doses (area under the concentration-time curve, AUC) of AA (AUC-AA) and of its genotoxic metabolite glycidamide (GA) (AUC-GA) is used as a basis for extrapolation between exposure levels and between species. In this study, AA-rich foods were given to nonsmokers: a high intake of 11 μg AA/kg body weight (bw) and day for 4 days or an extra (medium) intake of 2.5 μg AA/kg bw and day for a month.

Neutral and phenolic brominated organic compounds of natural and anthropogenic origin in northeast Atlantic Greenland shark (Somniosus microcephalus).

In the present study, muscle and liver tissue from 10 female Greenland sharks (Somniosus microcephalus) collected in Icelandic waters were analyzed for neutral and phenolic brominated organic compounds, including polybrominated diphenyl ethers (PBDEs) and the structurally related methoxylated (MeO) and hydroxylated (OH) PBDEs. Hydroxylated PBDEs exist both as natural products and as metabolites of the anthropogenic PBDEs, whereas MeO-PBDEs appear to exclusively be of natural origin. Other compounds examined were 2',6-dimethoxy-2,3',4,5'-tetrabromodiphenyl ether (2',6-diMeO-BDE68), 2,2'-dimethoxy-3,3',5,5'-tetrabromobiphenyl (2,2'-diMeO-BB80), 2,4,6-tribromoanisol (2,4,6-TBA) and 2,4,6-tribromophenol, all of natural origin, although 2,4,6-TBA and its phenolic counterpart may also be of anthropogenic origin.

Significantly higher polybrominated diphenyl ether levels in young U.S. children than in their mothers.

While young children are rarely included in biomonitoring studies, they are presumed to be at greater risk of ingesting environmental contaminants-particularly those that accumulate in foods or shed from consumer products. The widely used fire retardants polybrominated diphenyl ethers (PBDEs) are ubiquitous contaminants in the indoor environment and are widely detected at higher levels in Americans than in individuals from other countries. However, there are only three studies of PBDEs in U.

Alcohol influence on acrylamide to glycidamide metabolism assessed with hemoglobin-adducts and questionnaire data.

Our purpose was to investigate whether alcohol (ethanol) consumption could have an influence on the metabolism of acrylamide to glycidamide in humans exposed to acrylamide through food. We studied a subsample from a population-based case-control study of prostate cancer in Sweden (CAPS). Questionnaire data for alcohol intake estimates was compared to the ratio of hemoglobin-adduct levels for acrylamide and glycidamide, used as a measure of individual differences in metabolism.

Polybrominated diphenyl ethers in aircraft cabins--a source of human exposure?

Commercial aircrafts need a high degree of fire protection for passenger safety. Brominated flame retardants (BFRs), including polybrominated diphenyl ethers (PBDEs), may be used for this purpose. Because PBDEs readily absorb to dust particles, aircraft crew and passengers may receive significant PBDEs exposure via inhalation.

Internal doses of acrylamide and glycidamide in mice fed diets with low acrylamide contents.

The formation of acrylamide during heating of certain foodstuffs constitutes a potential health hazard. The health risk assessment should be based on knowledge about the relation between dietary exposure to acrylamide and internal doses of acrylamide and its genotoxic metabolite glycidamide. The primary aim of this study in mice was to measure these relationships at low levels of acrylamide intake through the diet.

Temporal trends of polybrominated diphenyl ethers and hexabromocyclododecane in milk from Stockholm mothers, 1980-2004.

Environmental and human exposures to brominated flame retardants (BFR) have been of emerging concern since some BFR are persistent and bioaccumulative compounds. Among those, polybrominated diphenyl ethers (PBDE) have frequently been reported in low to high ng/g concentrations in human blood around the world while hexabromocyclododecane (HBCDD) only occasionally has been reported and then in the low ppb concentrations in human blood. The present study concerns PBDE congener and HBCDD concentrations in human milk from Stockholm from 1980 to 2004.

Children show highest levels of polybrominated diphenyl ethers in a California family of four: a case study.

Polybrominated diphenyl ethers (PBDEs), a major class of flame retardants, are ubiquitous environmental contaminants with particularly high concentrations in humans from the United States. This study is a first attempt to report and compare PBDE concentrations in blood drawn from a family. Serum samples from family members collected at two sampling occasions 90 days apart were analyzed for PBDE congeners.

Levels of PCBs and their metabolites in the serum of residents of a highly contaminated area in eastern Slovakia.

The over-riding aim of the present investigation was to obtain information concerning exposure that can be used as a basis for studies on the health of individuals residing in the Michalovce area of eastern Slovakia which is heavily contaminated by polychlorinated biphenyls (PCBs). Accordingly, this work focused on determination of serum concentrations of hydroxylated (OH-PCBs) and methylsulfonyl-substituted (MeSO2-PCBs) metabolites of PCBs. One hundred and twenty-two men and women, 20-59 years of age, living in the contaminated area and 175 from the control Stropkov/Svidnik district were selected randomly from 2047 sampled individuals.

Gas chromatography and mass spectrometry of methoxylated polybrominated diphenyl ethers (MeO-PBDEs).

Twenty-six methoxylated polybrominated diphenyl ethers (MeO-PBDEs) were characterized by gas chromatography (GC) on four different GC columns with different lengths and polarities, as well as by mass spectrometry using three ionization techniques, electron ionization (EI), electron capture negative ionization (ECNI) and positive ion chemical ionization (PICI). MeO-PBDE congeners with similar retention times on a nonpolar GC column were separated when analyzed on a polar GC column. EI can be used to determine the position of the methoxy substituent (ortho, meta or para) relative to the diphenyl ether oxygen in the MeO-PBDEs.

Concentrations of polybrominated diphenyl ethers, polychlonnated biphenyls, and polychlorobiphenylols in serum from pregnant Faroese women and their children 7 years later.

The objective of this study was to assess blood concentrations of polybrominated diphenyl ethers (PBDEs) and polychlorinated biphenyls (PCBs), and their polychlorobiphenylol (OH-PCB) metabolites in humans with a high seafood intake. Samples were obtained from pregnant women in the Faroe Islands in 1994-1995 and from their children at 7 years of age to examine maternal transfer of the compounds to their child, age-dependent metabolism, and temporal changes. Maternal serum was dominated by 2,2',4,4'-tetrabromodiphenyl ether (BDE-47), while 2,2',4,4',5,5'-hexabromodiphenyl ether (BDE-153) prevailed in the children's serum seven years later.

Identification, quantification, and synthesis of a novel dimethoxylated polybrominated biphenyl in marine mammals caught off the coast of Japan.

Bioaccumulation of persistent organic compounds can eventually lead to concentrations in wildlife and humans that are deleterious to health. The present paper documents the identification, quantification, and synthesis of a novel compound, 2,2'-dimethoxy-3,3',5,5'-tetrabromobiphenyl (2,2'-diMeO-BB80), present in the marine mammals Striped dolphin (Stenella coeruleoalba), Bottlenose dolphin (Tursiops truncatus), Minke whale (Balaenoptera acutorostrata), and Baird's beaked whale (Berardius bairdii) caught in the Pacific Ocean. Identification was based on comparison of the relative retention times of the compound on two gas chromatographic columns of different polarities to those of an authentic standard.

Identification of hydroxylated metabolites in 2,2',4,4'-tetrabromodiphenyl ether exposed rats.

Faeces from day 1-5 of orally administered 2,2',4,4'-tetrabromodiphenyl ether (BDE-47) in rat have been analysed for hydroxylated metabolites. Six hydroxylated tetrabrominated diphenyl ethers, as well as three hydroxylated tribrominated diphenyl ethers found, were structurally identified. They were 2'-hydroxy-2,4,4'-tribromodiphenyl ether, 3'-hydroxy-2,4,4'-tribromodiphenyl ether, 4'-hydroxy-2,2',4-tribromodiphenyl ether, 6-hydroxy-2,2',4,4'-tetrabromodiphenyl ether, 2'-hydroxy-2,3',4,4'-tetrabromodiphenyl ether, 3-hydroxy-2,2',4,4'-tetrabromodiphenyl ether, 5-hydroxy-2,2',4,4'-tetrabromodiphenyl ether, 4'-hydroxy-2,2',4,5'-tetrabromodiphenyl ether and 4-hydroxy-2,2',3,4'-tetrabromodiphenyl ether.

Hydroxylated PCB metabolites in nonhatched fulmar eggs from the Faroe Islands.

Thirty-six polychlorinated biphenylols (OH-PCBs) congeners were characterized in Fulmar (Fulmarus glacialis) eggs collected from the Faroe Islands. The seven most abundant congeners were quantified in 19 samples, and the sigmaOH-PCB concentrations ranged between 0.92 and 4.