The addition of the "dioxin-like" polychlorinated biphenyl (PCB) congeners to the assessment of risk associated with the 2,3,7,8-chlorine substituted dioxins and furans has dramatically increased the number of laboratories worldwide that are developing analytical procedures for their detection and quantitation. Most of these procedures are based on established sample preparation and analytical techniques employing high resolution gas chromatography/ high resolution mass spectrometry (HRGC/HRMS), which are used for the analyses of dioxin/furans at low parts-per-trillion (ppt) levels. A significant and widespread problem that arises when using these sample preparation procedures for the analysis of coplanar PCBs is the presence of background levels of these congeners. Industrial processes, urban incineration, leaking electrical transformers, hazardous waste accidents, and improper waste disposal practices have released appreciable quantities of PCBs into the environment. This contamination has ...
Polychlorinated dioxins, dibenzofurans (PCDD/PCDF) and polychlorinated biphenyls (PCBs), are persistent organic pollutants (POPs) that bioaccumulate in lipids and may enter the food chain through animal products. Recently, Polish authorities discovered a free range farm whose eggs exceeded national standards for dioxin contamination two-fold. Piskorska-Pliszczynska et al.1 evaluated samples from that farm to determine the likely source of the dioxin exposure and to quantify the bioaccumulation of PCDD/Fs and PCBs in the tissues and eggs of the affected hens. They took specimens from the commercial feed and the soil of the free range areas. A veterinarian also performed necropsies and sampled muscle, abdominal fat, liver tissue, ovarian follicles, and whole eggs present in the oviducts. The researchers identified 35 PCDD/F and PCB congeners of interest, including dioxin-like polychlorinated biphenyls (DL-PCBs) and non-dioxin-like polychlorinated biphenyls (NDL-PCBs), using gas chromatography ...
Polychlorinated biphenyls (PCB) are persistent environmental chemicals that are known thyroid hormone disrupters. Frequently the disruption of one endocrine axis and the timing of the disruption have an impact on other interdependent hormonal responses. Although the mechanisms for the interdependency of thyroid hormones and leptin have not been fully characterized, both are linked to development and regulation of metabolism. Furthermore, PCB accumulation in depot fat could potentially alter leptin production. In the present study 15-and 30-day-old Sprague-Dawley rats were exposed gestationally and lactationally to 1.25 ppm of Aroclor 1254®, a mixture of 52 PCB congeners, via maternal diet, to determine the effect on leptin and thyroid hormones. Additionally, young adult female rats were fed 1.25 PCB for 21 days and the same hormones were assessed. Serum leptin concentrations were determined by a sensitive murine leptin ELISA (DSL, Inc., Webster, TX). Serum thyroid hormone levels were determined ...
Article Congener-specific analysis of polychlorinated biphenyl in human blood from Japanese. Polychlorinated biphenyl (PCB) congeners were analyzed by high resolution gas chromatography/high resolution mass spectrometry (HRGC/HRMS) of whole blood sam...
Polychlorinated biphenyls (often shortened to PCBs) are organic chemical compounds that contain chlorine atoms. They were used in industrial chemistry, and to make certain transformers, capacitors, and cooling fluids. The Stockholm Convention on Persistent Organic Pollutants declared them to be among the worst chemical pollutants. Their use has been banned worldwide, since 2001. The mode of action of these substances is similar to that of dioxin. Polychlorinated biphenyls were widely used, and they can be found in the atmosphere, the soil, and the bodies of water anywhere on the earth. In the short term, these substances are not very toxic, but they accumulate in the body. They are teratogens, and may cause cancer. ...
PCBs are industrial chemicals that have neurotoxic effects, and studies indicate that they interfere with normal functions of the endocrine system. Although the manufacturing of PCBs was banned in the 1970s, they remain a major contaminant of the environment and of human tissues. Epidemiological studies show that exposure to PCBs during intrauterine development is highly associated with measurable neurological deficits in the offspring. In addition, deficits associated with PCBs are inversely associated with maternal thyroid hormone (TH) levels. This suggests that PCBs interfere with TH action in the fetal brain. Using in situ hybridization to measure HES-1 and HES-5 mRNA (direct markers of Notch activity), our laboratory has found that both maternal thyroid status and maternal exposure to PCBs influences Notch signaling in the fetal rat brain. We found that Aroclor 1254 produces a dose-dependent increase in HES-1 expression in the ventricular zone. Recent evidence suggests that Notch signaling ...
Aquatic organisms passively accumulate hydrophobic organic compounds, such as polychlorinated biphenyls, even when ambient water concentrations of the contaminant are below analytical detection limits. However, contaminant concentrations in tissue samples are subject to an inherently high level of variability due to differences in species, life stage, and gender bioconcentration potentials. Semipermeable membrane devices (SPMDs) were used to sample Aroclor 1254, a mixture of readily bioconcentrated polychlorinated biphenyls (PCBs), in a contaminated wetland near Flat Top, WV. The devices consisted of triolein, a lipid found in fish, enclosed in a polyethylene membrane. SPMDs were deployed in the water column and in direct contact with wetland sediments along a previously identified concentration gradient of PCBs. The devices were retrieved after a 25-day exposure period. Analytes were recovered by dialyzing the devices in nanograde hexane. Hexane dialysates were condensed and analyzed by gas
EWGs Tap Water Database Polychlorinated biphenyls (PCBs) results for Phoenixville Water Dept | Polychlorinated biphenyls (PCBs). Find out what is in your tap water
Background and aims: Despite the endocrine system activity exhibited by polychlorinated biphenyls (PCBs), recent studies have shown little association between PCB exposure and breast cancer mortality. To evaluate the relation between PCB exposure and breast cancer incidence, a more sensitive endpoint than mortality, we studied women exposed to PCBs while employed in capacitor manufacturing facilit
In vitro analysis of polychlorinated biphenyls (PCBs) and 2,3,4,7,8-pentachlorodibenzofuran (PCDF) cellular toxicity in PLC/PRF/5 cell proliferation--the effect of ursodeoxycholic acid, inchin-gorei-san and shou-saiko-to on cell toxicity.
Other data set: Additional PCB congeners are reported under data file name PCBPOL_F. Among these PCB congeners PCB 105, 114, 118, 156, 157, 167 and 189 has a toxic equivalence factor (TEF) and may be used with this data set for calculating a total TCDD equivalence.. Subsample Weights. PCDDs, PCDFs, and cPCBs were measured in a one-third subsample of participants 12 years and older. Special sample weights are required to analyze these data properly. Specific sample weights for this subsample are included in this data file and should be used when analyzing these data.. Samples were pooled in groups of 8 samples per pool within 40 demographic groups. The analysis of NHANES 2009-2010 pooled-sample data must be conducted with the basic demographic variables provided in this data file. This pooled-sample data file cannot be linked to other NHANES 2009-2010 data. Because each sample person does not have an equal probability of selection, sample weighting is needed to produce correct population ...
Persistent organic pollutants (POPs) are fat soluble chemical substances that persist in the environment and bioaccumulate in the food chain. Through long-range environmental transportation by air, water and migratory species they are transferred to new locations distant from the source of release and might cause adverse effects to human health and to the environment. POPs comprise pesticides, industrial chemicals and unwanted by-products. The European Commission has implemented food and feed legislations concerning maximum permitted levels (MPLs) of polychlorinated dibenzo-p-dioxins and furans (PCDD/Fs), dioxin-like polychlorinated biphenyls (DLPCBs), polycyclic aromatic hydrocarbons (PAHs) and organochlorine pesticides (OCPs). Fish and consequently fishmeal and fish oil has been identified as one of the most important contributors to the level of dioxins and DL-PCBs in food and feed products. Fish caught in some of the North-European fishing areas contain high dioxin and PCB levels resulting ...
Polychlorinated Biphenyls (PCBs) are synthetic organic chemicals. Uses include plasticisers in paints, plastics & rubber PCBs are a persistent organic pollutant
The microbial synthesis of polyhydroxyalkanoates (PHA) from organic wastes is a valuable process to valorize available renewable resources, such as food wastes and biological sludge. Bioplastics find many applications in various sectors, from medical field to food industry. However, persistent organic pollutants could be transferred from wastes to the final product. The present paper demonstrates that the use of municipal wastes in PHA production is safe for the environment and human health and provides a polychlorinated biphenyl (PCB) profile in both commercial and waste-based PHA samples. PCB analysis in several PHA samples showed very low concentrations of the target analytes. Commercial PHA samples showed a similar PCB level with respect to PHA samples from municipal waste/sludge and higher than PHA samples from fruit waste. For all analyzed PCBs, detected concentrations were consistently lower than the ones reported in regulatory framework or guidelines.
Background: Polychlorinated biphenyls (PCBs) and their hydroxylated metabolites (HO-PCBs) interfere with thyroid hormone action both in vitro and in vivo. However, epidemiologic studies on the link between PCB exposure and thyroid function have yielded discordant results, while very few data are available for HO-PCBs. Objectives: Our study aimed at investigating the relationship between clinically available markers of thyroid metabolism and serum levels of both PCBs and HO-PCBs. Subjects and Methods: In a group of 180 subjects, thyroid-stimulating hormone (TSH) and free thyroxin (fT4), 29 PCBs (expressed both in lipid weight and in wet weight) and 18 HO-PCBs were measured in serum. Results: In regression models, adjusted for gender, age, current smoking behavior, BMI and total lipid levels, serum levels of 3HO-PCB118 and 3HO-PCB180, and PCB95lw, PCB99lw and PCB149lw were independent, significant predictors of fT4. A stepwise, multiple regression with gender, age, current smoking behavior, BMI and total
Polychlorinated biphenyl (PCB) exposure may affect serum concentrations of polyunsaturated fatty acids (PUFAs) by inhibiting desaturases Δ5 and Δ6 that drive their synthesis from precursor fatty acids. Such changes in the composition of fatty acids may affect cardiovascular disease risk, which is thought to increase at elevated PCB exposures. This population-based cross-sectional study examined 712 Faroese men and women aged 70-74 years. The serum phospholipid fraction of fasting blood samples was used to determine the PUFA profile, including linoleic acid, dihomo-γ-linolenic acid, arachidonic acid, eicosatrienoic acid, and other relevant fatty acids. Ratios between precursor and metabolite fatty acids were used as proxies for Δ5 and Δ6 desaturase activity. Tertiles of serum-PCB concentrations were used in multiple regression analyses to determine the association between the exposure and desaturase activity. In multiple regression models, PCB exposure was inversely related to the estimated ...
The most common technique used for the analysis of Organochlorine pesticides (OCPs) and polychlorinated biphenyls (PCBs) at trace level is gas chromatography coupled to an electron capture detector (GC-ECD). Click to read more...
Chromosomal abnormalities contribute substantially to reproductive problems, but the role of environmental risk factors has received little attention.,We evaluated the association of polychlorinated biphenyl (PCB) and dichlorodiphenyldichloroethylene (p,p-DDE) exposures with sperm sex-chromosome disomy.,We conducted a cross-sectional study of 192 men from subfertile couples. We used multiprobe fluorescence in situ hybridization (FISH) for chromosomes X, Y, and 18 to determine XX, YY, XY, and total sex-chromosome disomy in sperm nuclei. Serum was analyzed for concentrations of 57 PCB congeners and p,p-DDE. Poisson regression models were used to calculate incidence rate ratios (IRRs) for disomy by exposure quartiles, controlling for demographic characteristics and semen parameters.,The median percent disomy was 0.3 for XX and YY, 0.9 for XY, and 1.6 for total sex-chromosome disomy. We observed a significant trend of increasing IRRs for increasing quartiles of p,p-DDE in XX, XY, and total ...
Dioxin-like chemicals and brominated flame retardants are ubiquitous in the environment, despite the introduction of international prohibitions and restrictions. These chemicals do not remain in the vicinity of their source, instead they can be transported over long distances, in fact even to pristine areas in the northern latitudes. However, there have been rather few time series experiments monitoring the trends in the levels of chlorinated and brominated forms of these chemicals in the environment. In this study, the concentrations of polychlorinated dibenzo-p-dioxins and -furans (PCDDs/Fs), polychlorinated biphenyls (PCBs) and polybrominated diethyl ethers (PBDEs) were measured in the liver and muscle of bank voles (Myodes glareolus) caught in a remote area in Finnish Lapland during 1986-2007. Five time points were selected: years 1986, 1992, 1998, 2003 and 2007. The levels of PCDDs/Fs and PCBs declined from 1986 until 2003 in both females and males, but tended to increase again in 2007. The peak
Despite production having stopped in the 1970s, polychlorinated biphenyls (PCBs) represent persistent organic pollutants that continue to pose a serious human health risk. Exposure to PCBs has been...
Several studies have suggested that exposure to persistent pollutant, polychlorinated biphenyls (PCBs), may increase the risk of developing endometriosis
Background: Multiple studies have suggested a relationship between adult exposures to environmental organochlorines and fecundability. There is a paucity of data, however, regarding fetal exposure to organochlorines via the mothers blood and fecundability of adult female offspring. Methods: Data from a two-generation cohort of maternal fisheaters was investigated to assess female offspring fecundability. Serum concentrations of polychlorinated biphenyls (PCBs) and 1,1-bis-(4-chlorophenyl)-2,2-dichloroethene (DDE) in Michigan female anglers were serially measured between 1973 and 1991 and used to estimate in utero exposure in their female offspring using two different methods. The angler cohort included 391 women of whom 259 provided offspring information. Of 213 daughters aged 20-50, 151 participated (71 %) and provided information for time intervals of unprotected intercourse (TUI). The daughters reported 308 TUIs (repeated observations), of which 288 ended in pregnancy. We estimated the ...
PCBs are a group of synthetic organic chemicals that can cause a number of different harmful effects. There are no known natural sources of PCBs in the environment. PCBs are either oily liquids or solids and are colorless to light yellow. Some PCBs are volatile and may exist as a vapor in air. They have no known smell or taste. PCBs enter the environment as mixtures containing a variety of individual chlorinated biphenyl components, known as congeners, as well as impurities
This testimony discusses the concerns of NIOSH on the proposed rule from the Environmental Protection Agency (EPA) regarding polychlorinated biphenyls (PCBs) in electrical transformers. NIOSH suggests that the rule is directed primarily toward allowing the use of PCB containing transformers as replacements for existing non PCB containing transformers in certain emergency situations where a non PCB
A mortality study was conducted in workers with at least 90 days exposure to polychlorinated biphenyls PCBs between 1946 and 1977. Vital status was established for 98.7% of the 7075 workers studied. In hourly male workers, the mortality from all cancers was significantly below expected standardized mortality ratio SMR=81 ; 95% confidence...
A method is described for the analysis of polychlorinated biphenyl (PCB) compounds in tissue samples. Cleanup by hexane-aceto-nitrile partitioning and Florisil column chromatography are performed on samples before oxidative treatment to convert DDE to DCBP. PCB components are then determined semi-quantitatively by TLC. No prior separation of PCB from chlorinated pesticides is required. The lower limit of sensitivity is 0.2 ?g....
Polychlorinated biphenyls (PCBs) and hydroxylated PCBs (OH-PCBs) were investigated in human adipose tissue samples collected from 20 women undergoing surgery. Mean sum of PCB and sum of OH-PCB levels were 737ng/g of lipid and 8pg/g of lipid, respectively. Among PCBs, congeners 180, 153, 138 and 170 were the most frequent and abundant, and together constituted 72% of the total amount of PCBs in adipose tissue. The PCB congener pattern and the frequencies and concentrations of non-dioxin-like and non-hydroxylated congeners observed in adipose tissue were similar in distribution and order of magnitude to the profile previously published in Spain but lower than that found in other European countries. Among OH-PCB congeners studied, 4-OH-PCB 107/118 was found at the highest concentrations followed by 3-OH-PCB 180 and 3-OH-PCB 138. To date, no information on levels of PCB metabolites in the Spanish population is available for comparison. These three predominant OH-PCBs contributed 97% of all OH-PCBs. ...
Linh hoạt thay thế cho Chất thải xử lý ô nhiễm Polychlorinated biphenyls (PCBs) và các hợp chất thơm khác được khử trùng bằng clo được phân phối trong đất, bùn cặn, cửa sông, vv, tại hơn 400 trang web trong Hoa Kỳ một mình. Clo béo hydrocarbon (CAHs), rộng rãi được sử dụng để tẩy dầu mỡ và làm sạch động cơ, phụ tùng ô tô, và các thành phần điện tử, chất gây ô nhiễm nghiêm trọng tại 358 lớn các trang web trong chất thải nguy hại Hoa Kỳ. ...
Article Abundances, Depositional Fluxes, and Homologue Patterns of Polychlorinated Biphenyls in Dated Sediment Cores from the Pearl River Delta, China. Despite the recent efforts to investigate the distribution and fate of persistent organic pollutan...
TY - JOUR. T1 - Serum persistent organic pollutants (POPs) and prostate cancer risk. T2 - A case-cohort study. AU - Lim, Jung eun. AU - Nam, Chungmo. AU - Yang, Jiyeon. AU - Rha, KoonHo. AU - Lim, Kyung Min. AU - Jee, Sun Ha. PY - 2017/7/1. Y1 - 2017/7/1. N2 - It is still unclear whether persistent organic pollutants (POPs) exposure increases the prostate cancer incidence risk. This prospective cohort study evaluated the associations between serum POPs concentrations and prostate cancer risk. Within a case-cohort study, we identified 110 people diagnosed with prostate cancer and randomly selected 256 sub-cohort participants without prostate cancer. Serum concentrations of 32 polychlorinated biphenyl (PCB) congeners and 19 organochlorine pesticides (OCPs) were measured. The hazard ratios (HRs) and 95% confidence interval (95% CI) for determining the associations between POPs and risk of prostate cancer were estimated using the weighted Cox regression model. Compared to the lowest tertile, ...
Polychlorinated dibenzo-p-dioxins, dibenzofurans, and polychlorinated biphenyls are persistent environmental pollutants which ubiquitously occur as complex mixtures and accumulate in the food and feed chain due to their high lipophilic properties. Of the 419 possible congeners, only 29 share a common mechanism of action and cause similar effects, the so called dioxin-like compounds. Dioxin-like compounds evoke a broad spectrum of biochemical and toxic responses, i.e. enzyme induction, dermal toxicity, hepatotoxicity, immunotoxicity, carcinogenicity as well as adverse effects on reproduction, development, and the endocrine system in laboratory animals and in humans. Most, if not all, of the aforementioned responses, are mediated by the aryl hydrocarbon receptor. In the present work, the elicited biochemical effects of a selection of dioxin-like compounds and the non dioxin-like PCB 153 were examined in mouse (in vivo) and in human liver cell models (in vitro). Emphasis was given to the main ...
5,5-Bis-trifluoromethyl-2,2-dichlorobiphenyl (5,5CF3-2,2PCB) is representative of a unique class of trifluoromethyl polychlorinated biphenyls (CF3-PCBs) found in sediments and fish of Lake Ontario, the Niagara river, and their tributaries. The potential hazard of 5,5CF3-2,2PCB was assessed by …
Epidemiological studies suggest that exposure to persistent organic pollutants such as organochlorines might induce cardiovascular disorders and diabetes. Some of these organochlorines, such as dioxins and some dioxin-like PCBs, have been characterised as anti-estrogenic due to their inhibition of estrogenic-induced responses. In the present pilot study, 40 female rats were subjected to either exposure to the dioxin-like 3,3,4,4,5-pentachlorobiphenyl (PCB 126) or vehicle, as well as ovariectomy (OVX) or sham operation in a 2 x 2 factorial design over 12 weeks to explore potential interactions between estrogen status and PCB 126 exposure on cardiovascular risk factors. PCB 126 increased heart weight and serum cholesterol levels in both groups. PCB 126 increased blood pressure in the sham-operated animals only. In conclusion, PCB 126 exposure in female rats resulted in effects on cardiovascular risk factors, such as serum cholesterol, blood pressure, and heart weight. Of these effects of PCB ...
This paper presents a detailed congener-specific estimate of PCB exposure to the UK population. The average PCB intake (i.e. the sum of IUPAC congeners No. 28, 44, 52, 61/74, 66, 99, 101, 105, 110, 118, 138, 151, 153, 156, 170, 180, 183, 187, 189, 194/205, 201, 202, 206 and 209) for the contemporary UK population was estimated to be 0.53 μg/person/day. Food consumption accounted for 97% of the PCB exposure, with fish, milk and dairy products, vegetables and meat and animal fat accounting for 32, 24, 24 and 15%, respectively. The congener pattern for different food products varied, with vegetables playing a major part in the intake of lower chlorinated compounds, whilst fatty foods such as fish, dairy products and meat, were of greater importance for the intake of higher chlorinated compounds. Theoretical body burdens and body fat concentrations of selected PCB congeners were derived for the UK population, based on the estimated contemporary human daily intake of PCBs and a number of ...
Looking for Biphenyl degradation? Find out information about Biphenyl degradation. C12H10 A white or slightly yellow crystalline hydrocarbon, melting point 70.0°C, boiling point 255.9°C, and density 1.9896, which gives plates or monoclinic... Explanation of Biphenyl degradation
1G3M: Crystallographic analysis of a hydroxylated polychlorinated biphenyl (OH-PCB) bound to the catalytic estrogen binding site of human estrogen sulfotransferase.
Jenna Ladd| July 11, 2017 In the largest study of its kind, UI researchers have detected polychlorinated biphenyls (PCBs) in six schools throughout the midwest. Polychlorinated biphenyls (PCBs) are a class of manmade organic chemicals that were heavily used in construction and industry from 1929 until they were banned in 1979. PCBs are now known to…
Polychlorinated biphenyls, or PCBs, are toxic, persistent, bioaccumulative, and lipophilic (fat-loving). This means that PCBs build up and are stored in fatty tissues and fluids, such as breast milk, and can be passed on to fetuses and infants during pregnancy and lactation. In humans PCBs are linked to increased rates of a number of cancers, including malignant melanoma; non-Hodgkins lymphoma; and brain, liver, and lung cancer. PCB poisonings in humans have caused fetal and infant death, birth defects, and brain damage in children exposed in the womb. PCBs are known to interfere with hormonal processes. In 1976, the manufacture of PCBs was banned in the United States because of concern for human health impacts, but are still widely found in the general population of the U.S. In humans, PCBs are associated with skin lesions, thyroid disruption, and altered menstrual cycling, as well as damage to the nervous, immune, and cardiovascular systems. PCB exposure in the womb or during lactation is ...
PCBs have been used for their electrical insulating properties in transformers, capacitors ( even in some domestic equipments), heat transfer and cooling systems, hydraulic systems and vaccum pumps, and a variety of other uses. Use of PCBs has now been restricted or stopped in numerous countries, but certain occupational groups are still exposed, notably in handling of chemical wastes, dealing with fires or accidents, working in or cleaning contaminated areas of servicing and dismantling old electrical apparatus; and the public in the vicinity of incinerators if the temperature is not high enough. Low levels of PCBs can be detected in many members of most industrial populations, and are concentrated in human milk. Poisoning by PCBs has been recognised as a result of occupational exposure, and in outbreaks in the general population, such as occurred in japan (Yusho disease), and in Taiwan, due to contamination of rice oil ...
Exposure to high concentrations of persistent organochlorines may cause fetal toxicity, but the evidence at low exposure levels is limited. Large studies with substantial exposure contrasts and appropriate exposure assessment are warranted. Within th
Commonly, cohort studies investigating multiple cancer rates can find a statistically significant positive association with a particular cancer, at a rate of 5 associations per 100 examined, because of a multiple comparison issue. Thus, in the evaluation of causality, both consistency and dose-response relationships must be shown, as stated above. In the case of PCB studies, there are, indeed, individual studies reporting associations that are not replicated in other studies, but examination of Table 4 shows for any single positive association reported in a published study, the other studies (usually larger or with longer follow-up) are null.. The largest study to date assessing risks related to PCB exposure was published by Kimbrough et al. (60). There were 7,075 PCB-exposed capacitor workers studied with 235,984 person-years of observation and 1,654 deaths. The workers were studied in a number of different ways, providing evidence of internal consistency. The study found no associations with ...
PCBs are now banned in the U.S. but can be found in old electrical equipment. From the U.S. National Library of Medicine. [ ]
INTERNATIONAL. IARC releases monograph on benzene. OECD…. …Draft test guidelines. …Risks of mixed exposures. …Validation studies of two in vitro test methods (skin corrosion and eye irritation). …Updated reporting templates. JECFA reports on food contaminants. WHO Expert Committee on Drug Dependence reviews a range of drugs including cannabis. EUROPE. REACH…. …Member State Committee (MSC) deliberations on substances of very high concern (SVHCs). …Draft recommendation for authorisation list. …Testing proposals involving vertebrate animals. …ECHA to derive occupational exposure limits. Classification and labelling…. …Proposal for harmonised classification and labelling. …RAC opinions on harmonised classification and labelling. Biocidal Products Regulation. …BPC opinions on seven active substances. EFSA…. …Evaluation of propylene glycol esters of fatty acids as a food additive. …Consideration of dioxins and dioxin-like polychlorinated biphenyls. …Assessment of ...
Sigma-Aldrich offers abstracts and full-text articles by [Marta G Commendatore, Marcos A Franco, Patricia Gomes Costa, Italo B Castro, Gilberto Fillmann, Gregorio Bigatti, José L Esteves, Marina L Nievas].
... is a condition caused by poisoning with polychlorinated biphenyls (PCBs) and polychlorinated dibenzofurans (PCDFs). This primarily refers to a specific mass poisoning with PCBs and PCDFs in rice bran oil, which occurred in northern Kyushu, Japan, in 1968. About 14,000 people who had consumed the contaminated rice oil in Japan were affected. Common symptoms included some abnormalities on the skin and eye tissues, irregular menstrual cycles and a lowered immune system. Other symptoms included fatigue, headache, cough, and unusual skin sores. Additionally, in children, there were reports of poor cognitive development.. An almost identical case occurred in Taiwan a decade later in 1979, known as Yu-cheng disease.. ...
(2007) Steinberg et al. Hormones and Behavior. Polychlorinated biphenyls (PCBs) are a family of toxicants that persist in measurable quantities in human and wildlife tissues, despite their ban in production in 1977. Some PCB mixtures can act as...
adshelp[at]cfa.harvard.edu The ADS is operated by the Smithsonian Astrophysical Observatory under NASA Cooperative Agreement NNX16AC86A ...
Retrospective analysis of archived soil samples collected and stored from long-term agricultural experiments in the UK has shown how soil organic chemical composition has changed over time. High molecular weight polycyclic aromatic hydrocarbons (e.g. benzo[a]pyrene) and polychlorinated dibenzo-p-dioxins and -furans have increased in concentration through this century as a result of cumulative atmospheric depositional inputs. Concentrations of polychlorinated biphenyls and low molecular weight hydrocarbons (e.g. phenanthrene) peaked in the late 1960s/early 1970s, but have declined subsequently. This reflects declining atmospheric inputs of these compounds and losses from surface soils by volatilisation back to the atmosphere and biodegradation. PCBs and low molecular weight PAHs exist predominantly in the vapour phase in air, whilst heavy PAHs and PCDD/Fs are predominantly particulate-bound. Outgassing from soils is probably the most important contemporary source of PCBs to the atmosphere in the ...
in Accreditation and Quality Assurance (2006), 11(1-2), 38-43. In the determination of contaminants (dioxins, polychlorinated biphenyls, polyaromatic hydrocarbons), cell-based assays are useful methods for screening purposes: they are mainly characterized by high ... [more ▼]. In the determination of contaminants (dioxins, polychlorinated biphenyls, polyaromatic hydrocarbons), cell-based assays are useful methods for screening purposes: they are mainly characterized by high sample throughput and lower costs than the Mass Spectrometry (MS)-based methods. Although cell-based assays can be sensitive enough for the determination of dioxins and related substances in agreement with the presently tolerable limits in food and feed (Regulation No. 2375/2001/EC and Directive 2003/57/EC respectively), their lack of specificity make their use rather questionable in control laboratories. In this paper, we present and compare results obtained from the analysis of a limited number of feed samples by both gas ...
① Water tanks breeding Medaka ② Medaka pair ( ♂ 1 - ♀ 1or2 ) ③ Collect fertilized eggs every morning. ⑥ Observe the embryos under stereo-microscope. ④ Incubate the eggs in an incubato r for 24 hours at 26±0.5 ℃. On the next day, remove dead eggs. Method of egg collection and observation ⑤ Settle the eggs into each well of a microtiter plate wit h 200 m l of dioxin solution. ⑦ RNA extraction ⑧ Quantitative RT- PCR
The Great Lakes Regional Pollution Prevention Roundtable provides a forum for information exchange among P2 professionals through meetings, working groups and information resources,
We have developed an approach to classify toxicants based upon their influence on profiles of mRNA transcripts. Changes in liver gene expression were examined after exposure of mice to 24 model treatments that fall into five well-studied toxicological categories: peroxisome proliferators, aryl hydrocarbon receptor agonists, noncoplanar polychlorinated biphenyls, inflammatory agents, and hypoxia-inducing agents. Analysis of 1200 transcripts using both a correlation-based approach and a probabilistic approach resulted in a classification accuracy of between 50 and 70%. However, with the use of a forward parameter selection scheme, a diagnostic set of 12 transcripts was identified that provided an estimated 100% predictive accuracy based on leave-one-out cross-validation. Expansion of this approach to additional chemicals of regulatory concern could serve as an important screening step in a new era of toxicological testing.. ...
Three chemicals, bisphenol A, butyraldehyde, and polychlorinated biphenyls, have been experimentally tested with C16orf71 for evidence of interaction.[26] Bisphenol A is suspected to cause impairment in male reproduction.[27] An experiment utilizing seminiferous tubule culture was conducted to observe the effects on meiosis and potential germ-line abnormalities.[27] Gene expression analysis revealed decrease expression for C16orf71 when exposed to the chemical.[27] Butyraldehyde has been observed to affect inflammatory responses in bronchial airway tissue on a genetic level.[28] Microarray analysis was used to determine levels of expression in human alveolar epithelial cells after exposure to the compound.[28] Results indicated decreased expression for C16orf71 when exposed to the chemical.[28] Polychlorinated biphenyl was used in an experiment to determine its effects on external male genital development.[29] Human fetal corpora cavernosa cells were used as the model tissue.[29] Toxicogenomic ...
In 1974, Congress passed the Safe Drinking Water Act. This law requires EPA to determine safe levels of contaminants in drinking water...
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52744-13-5 - UUTNFLRSJBQQJM-UHFFFAOYSA-N - 2,2,3,3,5,6-Hexachlorobiphenyl - Similar structures search, synonyms, formulas, resource links, and other chemical information.
AUTHORS NOTE: This article was originally intended as an online resource. Most documents, therefore, are referenced by their www publications. Most of these sources are available in print form. For more information on the Hudson River cleanup, please contact Riverkeeper (www.riverkeeper.org) and Hudson Watch (www.hudsonwatch.org or www.hudsonwatch.net).]. AGAINST PREVAILING SCIENTIFIC wisdom, an August 2001 General Electric press release declares that "there is no credible evidence that PCB exposure causes disease in people.". PCBs, polychlorinated biphenyls, are various mixtures of 209 individual chlorinated compounds first manufactured by Swann Chemical Company around 1880. PCBs were once considered a miracle-product for manufacturers because of their water insolubility, high tolerance for heat, and chemical stability.. These properties led to their widespread usage in the manufacturing of products as diverse as inks, vacuum pump fluids, carbonless paper, lubricants, heat transfer media, ...
In 2012, several school renovation projects were hindered by caulk. The reason: PCBs.. In Connecticut, the towns of Southington and Fairfield discovered PCBs in the window caulking of their middle school and high school, respectively. In both cases, the discovery led to an unexpected increase in cost. The clean-up can also be confusing, since PCBs leach from caulk into surrounding porous building materials, including masonry, wood, and concrete. In October, the USEPA issued a reinterpretation of PCB Bulk Product Waste, specifically to address this issue.. PCBs, short for Polychlorinated Biphenyls, were commonly used in electrical equipment and building materials, until Congress banned manufacture of the toxic chemical in 1979. PCBs were used in caulk to impart flexibility, and can still be present in buildings constructed or renovated in the 1950s through the 1970s. The USEPA states that caulk containing PCBs at levels ≥ 50 parts per million (ppm) must be removed. When disposed, the caulk is ...
For about 50 years, polychlorinated biphenyls (PCBs) were commonly used in industrial materials including, caulking, cutting oils, inks, paints and as dielectric fluids in electrical equipment such as transformers and capacitors. Concerns over health effects led to a North American ban of manufacturing PCBs in 1977. By the mid-1980s, an initiative was started to clean up contaminated areas and to phase out PCB-containing equipment and products that were still in use. This cleanup effort continues today.
Polychlorinated biphenyls (PCBs) were first synthesized in 1881, and commercial production in the United States began in 1929. PCBs were used in the electrical industry, as well as surface coatings and plasticizers in sealants, caulking, rubber, paints and asphalt. By 1972, scientific evidence showed that PCBs were an environmental and human health hazard and, in 1977, the manufacturing and non-electrical use of PCBs was banned. PCBs are a chemical that gained a lot of attention when scientific evidence began to suggest that it was an extremely dangerous substance.
But This Time Its Nature Doing the Dirty Work! In the late 1970s, the U.S. government banned a group of manmade chemical compounds known as PCBs (polychlorinated biphenyls) thanks to scientific evidence that they caused harm to both people and animals. This group of[...]
Several polychlorinated biphenyls (PCBs) and their hydroxylated metabolites display axial chirality. The Synthesis Core provided a series of chiral methoxylated PCB (MeO-PCB) standards to develop an enantioselective, gas chromatographic separation of MeO-PCBs using a chemically bonded -cyclodextrin column (Chirasil-Dex). The atropisomers of several MeO-PCBs could be separated on this column with resolutions ranging from 0.42-0.87 under isothermal or temperature programmed conditions. In addition, the enantiomeric fraction of OH-PCB 136 metabolites was determined in male and female rats treated with racemic PCB 136. As shown in the Figure, the second eluting enantiomer (E2) of 3-MeO-PCB 150 and 5-MeO-PCB 136 was enriched in the liver of male (A) and female (B) Sprague-Dawley rats. Rats received two intraperitoneal injection of racemic PCB 136 (2 × 100 mol/kg body weight, 2 × 36.1 mg/kg body weight) dissolved in corn oil (5 ml/kg body weight) on day 1 and 4, and were euthanized on day 7 ...
A study from Drexel University, in Philadelphia, has linked autism spectrum disorder with prenatal exposure to organochlorine chemicals. The researchers examined 1,144 children born in southern California between 2000 and 2003 with mothers who had enrolled in a state-sponsored prenatal screening program.. Blood tests were taken during their second trimester of pregnancy, a critical time for neurodevelopment, to measure exposure to organochlorine chemicals, including polychlorinated biphenyls (PCB) and pesticides such as DDT. These compounds were banned from production in the U.S. in 1977 but remain in the environment. Its well known that they can cross the placental barrier, impacting neurodevelopment in fetuses.. The researchers selected participants based on previous health diagnoses: 545 children with autism spectrum disorder and 181 with intellectual disabilities, plus 418 free of both issues as a control group. They found a 50 to 82 percent increased autism risk in children with the ...
Although it is demonstrated that meat and meat products have a major nutritional value because of their contribution of protein, amino acids, vitamin B12 and iron, their daily consumption also leads to exposure to toxic substances that reach us through the diet consumed by the animals, based on feed, forage or grass.. "The water drunk and the air breathed by livestock may be minor pathways of contamination to humans through the consumption of meat," said Mr Domingo.. "The risks to consumer health are related to micropollutants - generated by human activity through breeding or veterinary treatments - or toxins induced by the processing itself," the authors emphasise in the study.. The potential environmental toxins include inorganic elements such as arsenic, cadmium, mercury, lead, PAHs, PFAs, dioxins, pesticides and other persistent organic pollutants (POPs), such as polychlorinated biphenyls (PCBs).. Most of these substances are fat-soluble, so any food with high fat contents accumulates higher ...
Table 3. Semivolatile organic and polychlorinated biphenyl (PCB) compounds in streambed sediment from the Puget Sound Basin, September 1995 (micrograms per kilogram unless otherwise specified in less than 2 millimeter size fraction, dry weight; MDL, method detection limit; nd, not detected or below MDL; (), detection below MDL; E, detection level different from MDL, --, no published Canadian guidelines) ...
SPE Supra-Clean® FL Column 1 g/6 mL is recommended for extracting polar compounds when analyzing pesticides, Polychlorinated Biphenyls (PCB).
The L2000 PCB/Chloride Analyzer is an instrument used to test for polychlorinated biphenyls (PCBs) in soil, in transformer oil, and on surfaces. It works by first adding a chemical to the medium to be tested. The chemical removes all of the chloride from the PCB molecule. The instrument then measures the amount of chloride ions. Because PCBs contain chloride ions, the device is able to quantify the concentration of PCBs. The instrument converts the chloride reading into parts per million (ppm) ...
The Polychlorinated Biphenyls (PCBs) Profile can help identify which of the most toxic PCBs a patient has been exposed to and the body burden of the patient.
University of Iowa. Since polychlorinated biphenyls (PCBs) are produced through industrial processes or activities, it is assumed that people living in industrial cities will have higher concentrations of these toxic chemicals in their blood than people in rural communities.. Researchers at the University of Iowa say this isn´t the case. In a paper published in March in the journal Environmental Science & Technology, scientists report that mothers and children in East Chicago, Ind., and Columbus Junction, Iowa, had only subtle differences in their PCB blood levels. This analytical paper is the first to report such a comparison between two communities, between mothers and children, and including all 209 PCB compounds.. "This is not good news, and it certainly applies to all of us," says Keri Hornbuckle, professor of civil and environmental engineering in the UI College of Engineering and senior author on the paper. "I thought it would be worse in a very industrial city than in a rural community. ...
2001 article (updated 2005) from Health Canada and the Public Health Agency of Canada. Low levels of PCBs are found in the environment, and as result, in foods. The presence of these contaminants in foods and the environment means that everyone can be exposed to very low levels of PCBs. Exposure to these low levels does not appear to affect human health. However, PCBs can accumulate in the human body and remain there for years.
Read more about Exposure to common PCB toxins may up asthma symptoms on Business Standard. Children exposed to polychlorinated biphenyls (PCBs), which were commonly used in a range of industrial products, could be at increased risk of asthma symptoms, a new study has found.
The European Food Safety Authority has published a new report on levels of dioxins and polychlorinated biphenyls (PCBs) in food and feed. Canada Environment Siskinds LLP 16 Aug 2012
Shortly after the first successful synthesis of DB[a,l]P in 1966 (17 , 18) , carcinogenicity studies demonstrated that this PAH possesses extraordinarily high carcinogenic potency (19 , 20) . Twenty years later, several investigations confirmed the high carcinogenic potency of DB[a,l]P in mouse skin and rat mammary gland compared with that of other carcinogenic PAH, including benzo[a]pyrene and 7,12-dimethylbenz[a]anthracene (1, 2, 3, 4) . DB[a,l]P, like other PAHs, exerts genotoxic effects through DNA adduct formation in biological systems only after metabolism to reactive intermediates such as vicinal diol epoxides (21, 22, 23) . The oxidative steps in metabolic activation of carcinogenic PAH are catalyzed by P450 enzymes, especially P450 1A1 and 1B1 (10 , 11 , 24, 25, 26, 27, 28) . Whereas P450 1A1 is expressed in substantial amounts in most tissues only after induction by compounds such as 2,3,7,8-tetrachlorodibenzo-p-dioxin, MC, polychlorinated biphenyls (Aroclor 1254), or PAHs (24 , 29) , ...
GC Application #14775: PCB Congener Analysis on ZB-50 (Mix 1). Column used: Zebron™ ZB-50, GC Cap. Column 30 m x 0.32 mm x 0.25 µm, Ea Part#: 7HM-G004-11
GC Application #14776: PCB Congener Analysis on ZB-1701 (Mix 2). Column used: Zebron™ ZB-1701, GC Cap. Column 30 m x 0.32 mm x 0.25 µm, Ea Part#: 7HM-G006-11
Many human carcinogens are environmental carcinogens, for example, polychlorinated biphenyls (PCBs) from transformers. Other known carcinogens are tobacco smoke, aflatoxins (produced by moldy peanuts), sunlight (increase in malignant melanoma and squamous cell carcinoma), radiation, chemicals, dioxin, and benzene. Most authorities believe that the herpes viruses and papillomaviruses have a potential for producing cancerous changes. Patients with a history of certain diseases, such as hepatitis, have a higher incidence of liver cancer than patients without such history.. Normal cells have a mechanism to turn off cell growth with certain signals. In cancer, however, a change in the cells occurs so that they continue to grow. With a lack of control (switch does not turn off), the abnormal neoplastic cells continue to grow. The cell-surface antigens appear similar to the normal fetal types, so the body does not mount an immune response. The tumor stem cells have chromosomal abnormalities, ...
Monsanto is being sued by three cities in California and the state of Washington due to impacts from contamination by their PCBs. Monsantos motion to dismiss lawsuits over PCB (polychlorinated biphenyls) contamination filed by the California cities of… Read More. ...
There are a number of industrial chemicals that have estrogenic effects, meaning that they can bind and stimulate the bodys estrogen receptors. Some examples of these compounds are: PCB (Polychlorinated biphenyl), BPA (Bisphenol A) and phthalates. Most of us are familiar with these substances from news reports of their being banned from manufacturing practices. The hormonal disruption caused by the accidental ingestion of these chemicals is associated with developmental abnormalities in babies, and with certain types of hormone sensitive cancers like breast or uterine cancer. These compounds have also been associated with infertility in male wildlife in regions of contamination. It would not be a far stretch to assume that similar effects would occur in human males exposed to the same substances ...
Simply because, if someone lies at a straight angle, the triggered to paper, glue, guide bindings, photos, sugar, coffee, hair, carpeting and clothing...
Associations of bisphenol A and polychlorinated biphenyls with spermatogenesis and steroidogenesis in two biological fluids from men attending an infertility clinic ...
aAdjusted for maternal age, prepregnancy BMI, parity, maternal smoking, maternal education, maternal alcohol intake, maternal cholesterol, maternal triglycerides, child birth weight, and sex. bEstimated in a Cox regression model with age as the underlying time scale. cEstimated in a logistic regression model. dEstimated with median concentrations in each tertile entered in the Cox or logistic regression models as a continuous variable. eSum of PCB congeners 118 and 156. fSum of PCB congeners 138, 153, 170, and 180. gSum of PCB congeners 118, 138, 153, 156, 170, 180 ...
PCBs are environmental toxins known to be transferred from mothers to babies across the placenta - and to damage babies mental and motor development. We k
The CAB and DIY packages miss the programmable oscillator and the analog to digital converter chips because they are rather expensive (about 6€ each, depending on order quantity) and cant be used without additional electronics. If you need their functionality its possible to add them later on because they come in leaded packages and are hand solderable. If people want boards containing these chips in addition to everything else I will try to add another assembly option. Update: The PCBs arrived a few days ago. They should get assembled during the next week. Update: The first three completely assembled PCBs are tested and work as expected (see test status). Ill do a 100% test of the remaining six, but Im quite confident that they will just work as well. This weekend Ill prepare everything for shipping and post a public announcement. ...
The telecom industry is today categorized by being able to wirelessly transmit large amounts of data between systems in a short time. A precondition for this is that the PCBs (printed circuit board) being developed and manufactured can handle and distribute large amounts of data internally. Often presented as multiple high-speed links up to 10-28 Gbit/s. The PCBs of today contains electric conductors, which all lead from one point to another, with no possibility of branching or flexibility without being rebuilt. A significant problem with all these electric conductors in the PCBs and all the PCBs close contact with each other is the interference building up between them. EMI is a general explanation for this, Electro Magnetic Interference. To avoid this problem and instead meet the constraints of EMC, Electro Magnetic Compatibility, these electric conductors can be replaced with optical conductors. This new concept with optical conductors is not initially going to replace all electric conductors ...
PF-03549184 ≥98% (HPLC); CAS Number: 1221971-47-6; Synonym: N-(3′,4′-dichloro[1,1′-biphenyl]-4-yl)-4-hydroxy-2H-1,2-benzothiazine-3-carboxamide 1,1-dioxide, PF-9184; Linear Formula: C21H14Cl2N2O4S; find Sigma-Aldrich-PZ0326 MSDS, related peer-reviewed papers, technical documents, similar products & more at Sigma-Aldrich.
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本书就如何使用的OrCAD设计套件来设计与制造印刷电路板(PCB)提供指导。它是针对想知道如何使用该软件以及深入了解软件包的功能和局限性的学生和有实践经验的工程师而编写的快速教程。该书力图达到两个目标 ...
Polychlorinated dibenzofurans (PCDFs) are a family of organic compounds with one or several of the hydrogens in the dibenzofuran structure replaced by chlorines. For example, 2,3,7,8-tetrachlorodibenzofuran (TCDF) has chlorine atoms substituted for each of the hydrogens on the number 2, 3, 7, and 8 carbons (see structure in the upper left corner of the second image). Polychlorinated dibenzofurans are much more toxic than the parent compounds, with properties and chemical structures similar to polychlorinated dibenzodioxins. These groups together are often inaccurately called dioxins. They are known teratogens, mutagens, and suspected human carcinogens. PCDFs tend to co-occur with polychlorinated dibenzodioxins (PCDDs). PCDFs can be formed by pyrolysis or incineration at temperatures below 1200 °C of chlorine containing products, such as PVC, PCBs, and other organochlorides, or of non-chlorine containing products in the presence of chlorine donors. Dibenzofurans are known persistent organic ...
Dioxins and dioxin-like compounds (DLCs) are compounds that are highly toxic environmental persistent organic pollutants (POPs). They are mostly by-products of various industrial processes - or, in case of dioxin-like PCBs and PBBs, part of intentionally produced mixtures. They include: Polychlorinated dibenzo-p-dioxins (PCDDs), or simply dioxins. PCDDs are derivatives of dibenzo-p-dioxin. There are 75 PCDD congeners, differing in the number and location of chlorine atoms, and seven of them are especially toxic, the most dangerous being 2,3,7,8-Tetrachlorodibenzodioxin (TCDD) Polychlorinated dibenzofurans (PCDFs), or furans. PCDFs are derivatives of dibenzofuran. There are 135 isomers, ten have dioxin-like properties. Polychlorinated/polybrominated biphenyls (PCBs/PBBs), derived from biphenyl, of which twelve are "dioxin-like". Under certain conditions PCBs may form dibenzofurans/dioxins through partial oxidation. Finally, dioxin may refer to 1,4-Dioxin proper, the basic chemical unit of the ...
Changes in atropisomer composition of chiral polychlorinated biphenyls (PCBs) and their mono- and dihydroxylated metabolites (OH- and diOH-PCBs) via rat cytochrome P450 2B1 (CYP2B1) mediated biotransformation were investigated in vitro. Rat CYP2B1 could stereoselectively biotransform chiral PCBs to generate meta-OH-PCBs as the major metabolites after 60 min incubations. Nonracemic enantiomer fractions (EFs: concentration ratios of the (+)-atropisomer or the first-eluting atropisomer over the total concentrations of two atropisomers) of 5-OH-PCBs, were 0.17, 0.20, 0.85, 0.77, and 0.41 for incubations with PCBs 91, 95, 132, 136, and 149, respectively. CYP-mediated stereoselective formation of diOH-PCBs from OH-PCBs was observed for the first time. After 60 min stereoselective biotransformation, the EFs of both 4-OH-PCB 95 and 5-OH-PCB 95 changed from racemic (i.e., 0.50) to 0.62 and 0.46, respectively. These transformations generated statistically nonracemic 4,5-diOH-PCB 95, with EFs of 0.53 and 0.58 for
Spens, K. (2003) Community strategy on dioxins, furans and polychlorinated biphenyls and the EU Implementation of the Stockholm Convention and the UN ECE Protocol on POPs. Persistent Toxic Substances Contamination of the European Region as a reflection of results of the GEF/UNEP Regional Based Assessment of Persistent Toxic Substances (RBA PTS) in Europe, the implementation of the Stockholm Convention and Community Strategy for Dioxins, Furans and PCBs ...
TY - JOUR. T1 - Inhibition of intercellular communication and induction of ethoxyresorufin-O-deethylase activity by polychlorobiphenyls, -dibenzo-p-dioxins and -dibenzofurans in mouse hepa1c1c7 cells.. AU - de Haan, L.H.J.. AU - Halfwerk, S.. AU - Hovens, S.E.L.. AU - de Roos, B.. AU - Koeman, J.H.. AU - Brouwer, A.. PY - 1996. Y1 - 1996. U2 - 10.1016/1382-6689(95)00006-2. DO - 10.1016/1382-6689(95)00006-2. M3 - Article. VL - 1. SP - 27. EP - 37. JO - Environmental Toxicology and Pharmacology. JF - Environmental Toxicology and Pharmacology. SN - 1382-6689. ER - ...
Since 1987, the World Health Organization (WHO) carried out global surveys on polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs) and polychlorinated biphenyls (PCBs) in human milk. This study presents a review of the three most recent surveys from 2000 to 2010, including DDT. The objective was to identify global quantitative differences and provide baseline information for 52 countries or provide time-trends for countries with previous data. Individual human milk samples were collected following a WHO-designed procedure and combined to form a national pooled sample. Here, we report global levels for PCDDs, PCDFs, PCBs and the sum of o,p′-DDT, p,p′-DDT, o,p′-DDE, p,p′-DDE, o,p′-DDD and p,p′-DDD (ΣDDTs). A concise risk-benefit evaluation related to human milk contamination with these persistent organic pollutants (POPs) was also done. Large global and regional differences were observed. Levels of PCDDs and PCDFs were highest in India and some European and ...
Dioxins refers to a group of persistent chlorinated chemical compounds that have similar chemical structures and properties, and have similar biological characteristics, including toxicity. Food Standards Australia New Zealand (FSANZ) has conducted an analytical survey of dioxins in a range of food sampled in Australia with the purpose of assessing the level of risk to human health associated with the dietary exposure of the Australian population to dioxins. The overall conclusion of this report is that, on the basis of the available data, taking into account all the inherent uncertainties and limitations, the public health and safety risk for all Australians from exposure to dioxins from foods is very low.. Dioxins includes the polychlorinated dibenzodioxins (PCDDs or dioxins), the closely related polychlorinated dibenzofurans (PCDFs or furans) and polychlorinated biphenyls (dioxin-like PCBs, or PCBs). These compounds can accumulate in the body fat of animals and humans and have a tendency ...
In this work, we examined the profile of metabolites produced from the doubly para-substituted biphenyl analogs 4,4-dihydroxybiphenyl, 4-hydroxy-4-chlorobiphenyl, 3-hydroxy-4,4-dichlorobiphenyl, and 3,3-dihydroxy-4,4-chlorobiphenyl by biphenyl-induced Pandoraea pnomenusa B356 and by its biphenyl dioxygenase (BPDO). 4-Hydroxy-4-chlorobiphenyl was hydroxylated principally through a 2,3-dioxygenation of the hydroxylated ring to generate 2,3-dihydro-2,3,4-trihydroxy-4-chlorobiphenyl and 3,4-dihydroxy-4-chlorobiphenyl after the removal of water. The former was further oxidized by the biphenyl dioxygenase to produce ultimately 3,4,5-trihydroxy-4-chlorobiphenyl, a dead-end metabolite. 3-Hydroxy-4,4-dichlorobiphenyl was oxygenated on both rings. Hydroxylation of the nonhydroxylated ring generated 2,3,3-trihydroxy-4-chlorobiphenyl with concomitant dechlorination, and 2,3,3-trihydroxy-4-chlorobiphenyl was ultimately metabolized to 2-hydroxy-4-chlorobenzoate, but hydroxylation of the ...
POLYCHLORINATED NAPHTHALENE (PCN) AND DIBENZOFURAN (PCDF) CONGENER PATTERNS FROM PHENOL PRECURSORS IN THERMAL PROCESS: [II] EXPERIMENTAL RESULTS FROM DICHLOROPHENOLS (DCPs) - Municipal waste incinerator;Thermal process;Combustion;Polychlorinated Naphthalenes;Polychlorinated Dibenzofurans;Chlorophenol;
Dioxins and polychlorinated biphenyls (PCBs) are toxic chemicals that persist in the environment and accumulate in the food chain. Their presence in the environment in Europe has declined since the 1970s, following concerted efforts by public authorities and industry.. In the context of EFSAs work, dioxins refers to two groups of compounds: Polychlorinated dibenzo-p-dioxins (PCDDs) and dibenzofurans (PCDFs). Dioxins have no technological or other use, but are generated in a number of thermal and industrial processes as unwanted and often unavoidable by-products. In contrast to dioxins, PCBs had widespread use in numerous industrial applications, and were produced in large quantities for several decades with an estimated total world production of 1.2-1.5 million tonnes, until they were banned in most countries by the 1980s.. Dioxins and PCBs are found at low levels in many foods. Longer-term exposure to these substances has been shown to cause a range of adverse effects on the nervous, immune ...
Dioxins and polychlorinated biphenyls (PCBs) are toxic chemicals that persist in the environment and accumulate in the food chain. Their presence in the environment in Europe has declined since the 1970s, following concerted efforts by public authorities and industry.. In the context of EFSAs work, dioxins refers to two groups of compounds: Polychlorinated dibenzo-p-dioxins (PCDDs) and dibenzofurans (PCDFs). Dioxins have no technological or other use, but are generated in a number of thermal and industrial processes as unwanted and often unavoidable by-products. In contrast to dioxins, PCBs had widespread use in numerous industrial applications, and were produced in large quantities for several decades with an estimated total world production of 1.2-1.5 million tonnes, until they were banned in most countries by the 1980s.. Dioxins and PCBs are found at low levels in many foods. Longer-term exposure to these substances has been shown to cause a range of adverse effects on the nervous, immune ...
Persistent organic pollutants (POPs) are a large group of chemicals widely used and produced in various industrial applications. Many cell culture/animal studies have shown that POPs can induce oxidative stress. Since such data is lacking in humans, we conducted a large population-based study to analyze associations between POPs and oxidative stress markers. We measured following POPs; 16 polychlorinated biphenyls (PCBs), 5 organochlorine (OC) pesticides, octachlorinated dibenzo-p-dioxin, and polybrominated diphenyl ether 47, and oxidative stress markers; homocysteine, reduced [GSH] and oxidized glutathione [GSSG], glutathione ratio [GSSG/GSH], total glutathione, oxidized low-density lipoprotein [ox-LDL], ox-LDL antibodies, conjugated dienes, baseline conjugated dienes of LDL, and total anti-oxidative capacity in plasma samples collected from 992 70-year old individuals (50% women) from the population-based Prospective Investigation of the Vasculature in Uppsala Seniors (PIVUS) cohort. Linear ...