Instruct: Given a question, retrieve documents that answer the question.
Query: polonium
The multiple nuclear meltdowns at the Fukushima plants beginning on March 11, 2011, are releasing large amounts of airborne radioactivity that has spread throughout Japan and to other nations; thus, studies of contamination and health hazards are merited. In the United States, Fukushima fallout arrived just six days after the earthquake, tsunami, and meltdowns. Some samples of radioactivity in precipitation, air, water, and milk, taken by the U.S. government, showed levels hundreds of times above normal; however, the small number of samples prohibits any credible analysis of temporal trends and spatial comparisons. U.S. health officials report weekly deaths by age in 122 cities, about 25 to 35 percent of the national total. Deaths rose 4.46 percent from 2010 to 2011 in the 14 weeks after the arrival of Japanese fallout, compared with a 2.34 percent increase in the prior 14 weeks. The number of infant deaths after Fukushima rose 1.80 percent, compared with a previous 8.37 percent decrease. Projecting these figures for the entire United States yields 13,983 total deaths and 822 infant deaths in excess of the expected. These preliminary data need to be followed up, especially in the light of similar preliminary U.S. mortality findings for the four months after Chernobyl fallout arrived in 1986, which approximated final figures.
The regular occurrence of a peak due to an unidentified substance (X) in the gas chromatographic traces obtained from phenolic extracts of urine from human pregnant and non-pregnant females has been reported. The biphasic excretion of X with maxima in the luteal phase of the ovulatory cycle and relatively high levels in the first trimester of pregnancy were noteworthy and suggested that the substance may have a biological significance. Close similarities between the excretory pattern, the chemical and chromatographic properties of X and of those of the known phenolic steroids suggested initially that this compound was steroidal in nature. The same, or a similar, substance seems to be excreted in the vervet monkey (Cercopithecus aethiops pygerythrus). We now report the excretory pattern of X in more detail, the isolation of the pure compound from pooled pregnancy urine and the chemical structure. The structure determined by mass spectrometry, IR spectroscopy and NMR spectrometry is: trans-(+/-)-3,4-bis[(3-hydroxyphenyl)methyl]dihydro-2-(3H)-furanone (HPMF) and was confirmed by synthesis.
This review explores the potential adverse impact of the increasing phosphorus content in the American diet on renal, cardiovascular, and bone health of the general population. Increasingly, studies show that phosphorus intakes in excess of the nutrient needs of a healthy population may significantly disrupt the hormonal regulation of phosphate, calcium, and vitamin D, which contributes to disordered mineral metabolism, vascular calcification, impaired kidney function, and bone loss. Moreover, large epidemiologic studies suggest that mild elevations of serum phosphate within the normal range are associated with cardiovascular disease (CVD) risk in healthy populations without evidence of kidney disease. However, few studies linked high dietary phosphorus intake to mild changes in serum phosphate because of the nature of the study design and inaccuracies in the nutrient composition databases. Although phosphorus is an essential nutrient, in excess it could be linked to tissue damage by a variety of mechanisms involved in the endocrine regulation of extracellular phosphate, specifically the secretion and action of fibroblast growth factor 23 and parathyroid hormone. Disordered regulation of these hormones by high dietary phosphorus may be key factors contributing to renal failure, CVD, and osteoporosis. Although systematically underestimated in national surveys, phosphorus intake seemingly continues to increase as a result of the growing consumption of highly processed foods, especially restaurant meals, fast foods, and convenience foods. The increased cumulative use of ingredients containing phosphorus in food processing merits further study given what is now being shown about the potential toxicity of phosphorus intake when it exceeds nutrient needs.
The elimination kinetics of polychlorinated biphenyls (PCBs) in humans is difficult to assess in observational studies, because PCB exposure is never completely abolished. In a community with high dietary PCB exposures from whale blubber, we examined two groups of children with increased body burdens from breast-feeding. Follow-up was from ages 4.5 years to 7.5 years (99 subjects) and 7 to 14 years (101 subjects). The calculations were performed by the use of structural equation models, with adjustment for body weight and dietary blubber intake as the main source of postnatal exposure. As a likely result of background exposures, apparent elimination half-lives were unexpectedly long when based on results from all cohort members. Subjects with exposures above the median and in the highest quartile showed half-lives of about 3-4 years for CB-138, and 4.5-5.5 years for CB-105 and CB-118; 6.5-7.5 years for CB-156, CB-170, and CB-187; and 7-9 years for CB-153 and CB-180. The longest half-lives correspond to elimination of the parent PCB solely with a daily fat excretion rate of 1-2 g, while shorter half-lives assume metabolic break-down.
In East Greenland polar bears (Ursus maritimus), anthropogenic organohalogen compounds (OHCs) (e.g., polychlorinated biphenyls, dichlorodiphenyltrichloroethane, and polybrominated diphenyl ethers) contributed to renal lesions and are believed to reduce bone mineral density. Because OHCs are also hepatotoxic, we investigated liver histology of 32 subadult, 24 adult female, and 23 adult male East Greenland polar bears sampled during 1999–2002. Light microscopic changes consisted of nuclear displacement from the normal central cytoplasmic location in parenchymal cells, mononuclear cell infiltrations (mainly portally and as lipid granulomas), mild bile duct proliferation accompanied by fibrosis, and fat accumulation in hepatocytes and pluripotent Ito cells. Lipid accumulation in Ito cells and bile duct hyperplasia accompanied by portal fibrosis were correlated to age, whereas no changes were associated with either sex or season (summer vs. winter). For adult females, hepatocytic intracellular fat increased significantly with concentrations of the sum of hexachlorocyclohexanes, as was the case for lipid granulomas and hexachlorobenzene in adult males. Based on these relationships and the nature of the chronic inflammation, we suggest that these findings were caused by aging and long-term exposure to OHCs. Therefore, these changes may be used as biomarkers for OHC exposure in wildlife and humans. To our knowledge, this is the first time liver histology has been evaluated in relation to OHC concentrations in a mammalian wildlife species, and the information is important to future polar bear conservation strategies and health assessments of humans relying on OHC-contaminated food resources.
Polychlorinated biphenyls (PCBs) are synthetic chemicals primarily used as coolants and insulators in electrical equipment. Although banned for several decades, PCBs continue to exist in the environment because of their long half-life, continued presence in items produced before the ban, and poor disposal practices. Epidemiological and experimental studies have identified exposure to PCBs as a potential risk factor for Parkinson’s disease, perhaps more so in females. The objective of this work was to examine the association between PCB levels in post-mortem human brain tissue and the diagnosis of Parkinson’s disease, as well as the degree of nigral depigmentation. We also sought to determine if this association was more significant when patients were stratified by sex. Post-mortem brain samples from control patients and those diagnosed with Parkinson’s disease were obtained from the Emory University Brain Bank and from the Nun Study. Concentrations of eight prevalent PCB congeners were extracted from post-mortem brain tissue and analyzed using gas chromatography-mass spectrometry. PCB congeners 153 and 180 were significantly elevated in the brains of Parkinson’s disease patients. When stratified by sex, the female Parkinson’s disease group demonstrated significantly elevated concentrations of total PCBs and specifically congeners 138, 153, and 180 compared to controls, whereas PCB concentrations in males were not significantly different between control and Parkinson’s disease groups. In a separate population of women (Nun Study) who had no clinical signs or symptoms of PD, elevated concentrations total PCB and congeners 138, 153 and 180 were also observed in post-mortem brain tissue exhibiting moderate nigral depigmentation compared to subjects with mild or no depigmentation. These quantitative data demonstrate an association between brain PCB levels and Parkinson’s disease-related pathology. Furthermore, these data support epidemiological and laboratory studies reporting a link between PCB exposure and an increased risk for Parkinson’s disease, including greater susceptibility of females.
Background Exposure to pesticides has been reported to increase the risk of Parkinson disease (PD), but identification of the specific pesticides is lacking. Three studies have found elevated levels of organochlorine pesticides in postmortem PD brains. Objective To determine whether elevated levels of organochlorine pesticides are present in the serum of patients with PD. Design Case-control study. Setting An academic medical center. Participants Fifty patients with PD, 43 controls, and 20 patients with Alzheimer disease. Main Outcome Measures Levels of 16 organochlorine pesticides in serum samples. Results β-Hexachlorocyclohexane (β-HCH) was more often detectable in patients with PD (76%) compared with controls (40%) and patients with Alzheimer disease (30%). The median level of β-HCH was higher in patients with PD compared with controls and patients with Alzheimer disease. There were no marked differences in detection between controls and patients with PD concerning any of the other 15 organochlorine pesticides. Finally, we observed a significant odds ratio for the presence of β-HCH in serum to predict a diagnosis of PD vs control (odds ratio, 4.39; 95% confidence interval, 1.67–11.6) and PD vs Alzheimer disease (odds ratio, 5.20), which provides further evidence for the apparent association between serum β-HCH and PD. Conclusions These data suggest that β-HCH is associated with a diagnosis of PD. Further research is warranted regarding the potential role of β-HCH as a etiologic agent for some cases of PD.
Perfluorooctanesulfonylfluoride (POSF)-based compounds have been manufactured and used in a variety of industrial applications. These compounds degrade to perfluorooctanesulfonate (PFOS) which is regarded as a persistent end-stage metabolite and is found to accumulate in tissues of humans and wildlife. PFOS, perfluorohexanesulfonate (PFHxS), perfluorooctanoate (PFOA), and perfluorooctanesulfonamide (PFOSA) have been found in human sera from the United States. In this study, concentrations of PFHxS, perfluorobutanesulfonate (PFBS), PFOS, perfluorohexanoic acid (PFHxA), PFOA, perfluorononanoic acid (PFNA), perfluorodecanoic acid (PFDA), perfluoroundecanoic acid (PFUnDA), perfluorododecanoic acid (PFDoDA), and PFOSA were measured in 85 samples of whole human blood collected from nine cities (eight provinces) in China, including Shenyang (Liaoning), Beijing (Hebei), Zhengzhou (Henan), Jintan (Jiangsu), Wuhan (Hubei), Zhoushan (Zhejiang), Guiyang (Guizhou), Xiamen (Fujian), and Fuzhou (Fujian). Among the 10 perfluorinated compounds (PFCs) measured, PFOS was the predominant compound. The mean concentration of PFOS was greatest in samples collected from Shenyang (79.2 ng/mL) and least in samples from Jintan (3.72 ng/mL). PFHxS was the next most abundant perfluorochemical in the samples. No age-related differences in the concentrations of PFOA, PFOS, PFOSA, and PFHxS were observed. Gender-related differences were found,with males higher for PFOS and PFHxS, and females higher in PFUnDA. Concentrations of PFHxS were positively correlated with those of PFOS, while concentrations of PFNA, PFDA, and PFUnDA were positively correlated with those of PFOA. There were differences in the concentration profiles (percentage composition) of various PFCs in the samples among the nine cities.
A number of chemicals have been shown to demonstrate neurotoxic effects either in human or laboratory animal studies. This article aims at evaluating the impact of exposure to several chemicals including: organophosphate, organochlorine pesticides, polychlorinated biphenyls (PCBs), mercury and lead on the neurodevelopment of children by reviewing the most recent published literature, and answer the question whether any progress has been made in the epidemiology of the neurodevelopment of children induced by exposure to those chemicals. The result of the presented studies show that exposure to the above-mentioned chemicals may impair the neurodevelopment of children. Neonates exposed to organophosphate pesticides demonstrated a higher proportion of abnormal reflexes, and young children had more attention problems. Exposure to organochlorine pesticides in children was associated with alertness, quality of alert responsiveness, cost of attention and other potential attention associated measures. The majority of studies indicate the negative impact of lead exposure at the level <10 µg/dl or even <5 µg/dl on the neurodevelopment of children. The results of studies on exposure to PCBs, mercury, and their effect on neurodevelopment are inconsistent. Some suggest that prenatal exposure to PCBs and mercury is related to performance impairments, attention and concentration problems, while other do not present any statistically significant association. The studies were mostly well designed, using prospective cohorts with the exposure assessment based on the biomarker of exposure. Concerning the covariates and confounders affecting the endpoints in most of the presented studies, confounders were included in data analysis. In order to recognize the early cognitive, motor and language outcomes of chemical exposures, well standardized tools were used for evaluating the neurodevelopmental effects and offer an early and fairly comprehensive measure of child development. Because the neurotoxicants may cross the placenta and the fetal brain, exposure consideration regarding the reduction of exposure to those chemicals should be implemented.
Many studies have investigated the neurodevelopmental effects of prenatal and early childhood exposures to organophosphate (OP) pesticides among children, but they have not been collectively evaluated. The aim of the present article is to synthesize reported evidence over the last decade on OP exposure and neurodevelopmental effects in children. The Data Sources were PubMed, Web of Science, EBSCO, SciVerse Scopus, SpringerLink, SciELO and DOAJ. The eligibility criteria considered were studies assessing exposure to OP pesticides and neurodevelopmental effects in children from birth to 18 years of age, published between 2002 and 2012 in English or Spanish. Twenty-seven articles met the eligibility criteria. Studies were rated for evidential consideration as high, intermediate, or low based upon the study design, number of participants, exposure measurement, and neurodevelopmental measures. All but one of the 27 studies evaluated showed some negative effects of pesticides on neurobehavioral development. A positive dose–response relationship between OP exposure and neurodevelopmental outcomes was found in all but one of the 12 studies that assessed dose–response. In the ten longitudinal studies that assessed prenatal exposure to OPs, cognitive deficits (related to working memory) were found in children at age 7 years, behavioral deficits (related to attention) seen mainly in toddlers, and motor deficits (abnormal reflexes) seen mainly in neonates. No meta-analysis was possible due to different measurements of exposure assessment and outcomes. Eleven studies (all longitudinal) were rated high, 14 studies were rated intermediate, and two studies were rated low. Evidence of neurological deficits associated with exposure to OP pesticides in children is growing. The studies reviewed collectively support the hypothesis that exposure to OP pesticides induces neurotoxic effects. Further research is needed to understand effects associated with exposure in critical windows of development.
BACKGROUND: Restriction of dietary phosphorus is a major aspect of patient care in those with renal disease. Restriction of dietary phosphorus is necessary to control for phosphate balance during both conservative therapy and dialysis treatment. The extra amount of phosphorus which is consumed as a result of phosphate-containing food additives is a real challenge for patients with renal disease and for dieticians because it represents a "hidden" phosphate load. The objective of this study was to measure phosphorus content in foods, common protein sources in particular, and comprised both those which included a listing of phosphate additives and those which did not. METHODS: Determinations of dry matter, nitrogen, total and soluble phosphate ions were carried out in 60 samples of foods, namely cooked ham, roast breast turkey, and roast breast chicken, of which, 30 were with declared phosphate additives and the other 30 similar items were without additives. RESULTS: Total phosphorus (290 ± 40 mg/100 g vs. 185 ± 23 mg/100 g, P < .001) and soluble phosphorus (164 ± 25 mg/100 g vs. 100 ± 19 mg/100 g, P < .001) content were higher in products containing additives than in foods without additives. No difference was detected between the 2 groups regarding dry matter (27.2 ± 2.0 g/100 g vs. 26.7 ± 1.9 g/100 g) or total nitrogen (3.15 ± 0.40 g/100 g vs. 3.19 ± 0.40 g/100 g). Consequently, phosphorus intake per gram of protein was much greater in the foods containing phosphorus additives (15.0 ± 3.1 mg/g vs. 9.3 ± 0.7 mg/g, P < .001). CONCLUSIONS: Our results show that those foods which contain phosphate additives have a phosphorus content nearly 70% higher than the samples which did not contain additives. This creates a special concern because this extra amount of phosphorus is almost completely absorbed by the intestinal tract. These hidden phosphates worsen phosphate balance control and increase the need for phosphate binders and related costs. Information and educational programs are essential to make patients with renal disease aware of the existence of foods with phosphate additives. Moreover, these facts highlight the need for national and international authorities to devote more attention to food labels which should clearly report the amount of natural or added phosphorus. Copyright © 2011 National Kidney Foundation, Inc. Published by Elsevier Inc. All rights reserved.
Using the infrastructure of the National Atmospheric Deposition Program (NADP), numerous measurements of radionuclide wet deposition over North America were made for 167 NADP sites before and after the Fukushima Dai-ichi Nuclear Power Station incident of March 12, 2011. For the period from March 8 through April 5, 2011, wet-only precipitation samples were collected by NADP and analyzed for fission-product isotopes within whole-water and filterable solid samples by the United States Geological Survey using gamma spectrometry. Variable amounts of (131)I, (134)Cs, or (137)Cs were measured at approximately 21% of sampled NADP sites distributed widely across the contiguous United States and Alaska. Calculated 1- to 2-week individual radionuclide deposition fluxes ranged from 0.47 to 5100 Becquerels per square meter during the sampling period. Wet deposition activity was small compared to measured activity already present in U.S. soil. NADP networks responded to this complex disaster, and provided scientifically valid measurements that are comparable and complementary to other networks in North America and Europe.
Polychlorinated naphthalenes (PCNs) are persistent, bioaccumulative, and toxic contaminants. Prior to this study, the occurrence of PCNs in human adipose tissues from the USA has not been analyzed. Here, we have measured concentrations of PCNs in human adipose tissue samples collected in New York City during 2003-2005. Concentrations of PCNs were in the range of 61-2500pg/g lipid wt. in males and 21-910pg/g lipid wt. in females. PCN congeners 52/60 (1,2,3,5,7/1,2,4,6,7) and 66/67 (1,2,3,4,6,7/1,2,3,5,6,7) were predominant, collectively accounting for 66% of the total PCN concentrations. Concentrations of PCNs in human adipose tissues were 2-3 orders of magnitude lower than the previously reported concentrations of polychlorinated biphenyls (PCBs) and polybrominated diphenyl ethers (PBDEs). Concentrations of PCNs were not correlated with PCB concentrations. The contribution of PCNs to dioxin-like toxic equivalents (TEQs) in human adipose tissues was estimated to be <1% of the polychlorinated dibenzo-p-dioxin/dibenzofuran (PCDD/F)-TEQs.
Four persons developed marked parkinsonism after using an illicit drug intravenously. Analysis of the substance injected by two of these patients revealed primarily 1-methyl-4-phenyl-1,2,5,6-tetrahydropyridine (MPTP) with trace amounts of 1-methyl-4-phenyl-4-propionoxy-piperidine (MPPP). On the basis of the striking parkinsonian features observed in our patients, and additional pathological data from one previously reported case, it is proposed that this chemical selectively damages cells in the substantia nigra.
We studied pregnancy-related changes in serum concentrations of five polychlorinated biphenyls (PCBs, CB 118, CB 138, CB 153, CB 156, CB 180), three hydroxylated PCB metabolites (4-OH-CB107, 4-OH-CB146, 4-OH-CB187), and pentachlorophenol (PCP). Median serum lipid content increased 2-fold between early (weeks 9-13) and late pregnancy (weeks 35-36) (N=10), whereas median PCB levels in serum lipids decreased 20-46%, suggesting a dilution of PCB concentrations in serum lipids. Nevertheless, strong positive intra-individual correlations (Spearman's r=0.61-0.99) were seen for PCBs during the whole study period. Thus, if samples have been collected within the same relative narrow time window during pregnancy, PCB results from one single sampling occasion can be used in assessment of relative differences in body burdens during the whole pregnancy period. Concentrations of OH-PCBs in blood serum tended to decline as pregnancy progressed, although among some women the concentrations increased at the end of pregnancy. Positive intra-individual correlations (r=0.66-0.99) between OH-PCB concentrations were observed during the first and second trimester, whereas correlations with third trimester concentrations were more diverging (r=-0.70-0.85). No decline in PCP concentrations was observed during pregnancy and no significant correlations were found between concentrations at different sampling periods. Our results suggest that for both OH-PCBs and PCP, sampling has to be more specifically timed depending on the time period during pregnancy that is of interest. The differences in patterns of intra- and inter-individual variability of the studied compounds may be due to a combination of factors, including lipid solubility, persistence of the compounds, distribution in blood, metabolic formation, and pregnancy-related changes in body composition and physiological processes. Copyright © 2010 Elsevier Ltd. All rights reserved.
Background and objectives: Uncooked meat and poultry products are commonly enhanced by food processors using phosphate salts. The addition of potassium and phosphorus to these foods has been recognized but not quantified. Design, setting, participants, & measurements: We measured the phosphorus, potassium, and protein content of 36 uncooked meat and poultry products: Phosphorus using the Association of Analytical Communities (AOAC) official method 984.27, potassium using AOAC official method 985.01, and protein using AOAC official method 990.03. Results: Products that reported the use of additives had an average phosphate-protein ratio 28% higher than additive free products; the content ranged up to almost 100% higher. Potassium content in foods with additives varied widely; additive free products all contained <387 mg/100 g, whereas five of the 25 products with additives contained at least 692 mg/100 g (maximum 930 mg/100 g). Most but not all foods with phosphate and potassium additives reported the additives (unquantified) on the labeling; eight of 25 enhanced products did not list the additives. The results cannot be applied to other products. The composition of the food additives used by food processors may change over time. Conclusions: Uncooked meat and poultry products that are enhanced may contain additives that increase phosphorus and potassium content by as much as almost two- and three-fold, respectively; this modification may not be discernible from inspection of the food label.
2,4-Dinitrophenol (DNP) is reported to cause rapid loss of weight, but unfortunately is associated with an unacceptably high rate of significant adverse effects. DNP is sold mostly over the internet under a number of different names as a weight loss/slimming aid. It causes uncoupling of oxidative phosphorylation; the classic symptom complex associated with toxicity of phenol-based products such as DNP is a combination of hyperthermia, tachycardia, diaphoresis and tachypnoea, eventually leading to death. Fatalities related to exposure to DNP have been reported since the turn of the twentieth century. To date, there have been 62 published deaths in the medical literature attributed to DNP. In this review, we will describe the pattern and pathophysiology of DNP toxicity and summarise the previous fatalities associated with exposure to DNP.
Flanders is densely populated with much industry and intensive farming. Sexual maturation of adolescents (aged 14-15 years) was studied in relation to internal exposure to pollutants. Serum levels of pollutants and sex hormones were measured in 1679 participants selected as a random sample of the adolescents residing in the study areas. Data on sexual development were obtained from the medical school examination files. Self-assessment questionnaires provided information on health, use of medication and lifestyle factors. In boys, serum levels of hexachlorobenzene (HCB), p,p'-DDE and polychlorinated biphenyls (sum of marker PCB138, 153 and 180) were significantly and positively associated with pubertal staging (pubic hair and genital development). Higher levels of serum HCB and blood lead were associated with, respectively, a lower and a higher risk of gynecomastia. In girls, significant and negative associations were detected between blood lead and pubic hair development; higher exposure to PCBs was significantly associated with a delay in timing of menarche. Environmental exposures to pollutants at levels actually present in the Flemish population are associated with measurable effects on pubertal development. However, further understanding of toxic mode of action and sensitive windows of exposure is needed to explain the current findings.
Death of dopaminergic neurons in Parkinson's disease (PD) may partially be caused by synthesis and accumulation of endogenous and exogenous toxins. Because of structural similarity to MPTP, beta-carbolines, like norharman and harman, have been proposed as putative neurotoxins. In vivo they may easily be formed by cyclization of indoleamines with e.g. aldehydes. For further elucidation of the role of beta-carbolines in neurodegenerative disorders harman and norharman levels in cerebrospinal fluid (CSF) were measured in 14 patients with PD and compared to an age- and sex-matched control group (n = 14). CSF levels of norharman and harman in PD were significantly higher compared to controls. These results may suggest a possible role of harman and norharman or its N-methylated carbolinium ions in the pathophysiological processes initiating PD. However the origin of increased levels of these beta-carbolines remains unclear. On the one hand one may speculate, that unknown metabolic processes induce the increased synthesis of harman and norharman in PD. On the other hand a possible impact of exogenous sources may also be possible.
Objective Phosphorus containing additives are increasingly added to food products. We sought to determine the potential impact of these additives. We focused on chicken products as an example. Methods We purchased a variety of chicken products, prepared them according to package directions, and performed laboratory analyses to determine their actual phosphorus content. We used ESHA Food Processor SQL Software to determine the expected phosphorus content of each product. Results Of 38 chicken products, 35 (92%) had phosphorus containing additives listed among their ingredients. For every category of chicken products containing additives, the actual phosphorus content was greater than the content expected from nutrient database. For example, actual phosphorus content exceeded expected phosphorus content by an average of 84 mg/100g for breaded breast strips. There was also a great deal of variation within each category. For example, the difference between actual and expected phosphorus content ranged from 59 to 165 mg/100g for breast patties. Two 100 g servings of additive containing products contain an average of 440 mg of phosphorus, or about half the total daily recommended intake for dialysis patients. Conclusion Phosphorus containing additives significantly increase the amount of phosphorus in chicken products. Available nutrient databases do not reflect this higher phosphorus content, and the variation between similar products makes it impossible for patients and dietitians to accurately estimate phosphorus content. We recommend that dialysis patients limit their intake of additive containing products and that the phosphorus content of food products be included on nutrition facts labels.
Polybrominated diphenyl ethers (PBDEs) are persistent organic chemicals used as flame retardants in textiles, plastics, and consumer products. Although PBDE accumulation in humans has been noted since the 1970s, few studies have investigated PBDEs within the gestational compartment, and none to date has identified levels in amniotic fluid. The present study reports congener-specific brominated diphenyl ether (BDE) concentrations in second-trimester clinical amniotic fluid samples collected in 2009 from fifteen women in southeast Michigan, USA. Twenty-one BDE congeners were measured by GC/MS/NCI. The average total PBDE concentration was 3795 pg/ml amniotic fluid (range: 337 – 21842 pg/ml). BDE-47 and BDE-99 were identified in all samples. Based on median concentrations, the dominant congeners were BDE-208, 209, 203, 206, 207, and 47 representing 23, 16, 12, 10, 9 and 6%, respectively, of the total detected PBDEs. PBDE concentrations were identified in all amniotic fluid samples from southeast Michigan, supporting a need for further investigations of fetal exposure pathways and potential impacts on perinatal health.
Background Persistent organic pollutants (POPs) are hazardous chemicals omnipresent in our food chain, which have been internationally regulated to ensure public health. Initially described for their potency to affect reproduction and promote cancer, recent studies have highlighted an unexpected implication of POPs in the development of metabolic diseases like type 2 diabetes and obesity. Based on this novel knowledge, this article aims at stimulating discussion and evaluating the effectiveness of current POP legislation to protect humans against the risk of metabolic diseases. Furthermore, the regulation of POPs in animal food products in the European Union (EU) is addressed, with a special focus on marine food since it may represent a major source of POP exposure to humans. Discussion There is mounting scientific evidence showing that current POP risk assessment and regulation cannot effectively protect humans against metabolic disorders. Better regulatory control of POPs in dietary products should be of high public health priority. Summary The general population is exposed to sufficient POPs, both in term of concentration and diversity, to induce metabolic disorders. This situation should attract the greatest attention from the public health and governmental authorities.
The present study evaluates the genotoxic potential of potassium sorbate (PS) in cultured and isolated human lymphocytes. To assess the damage caused by PS in humans, we designed in vitro experiments by measuring chromosomal aberrations (CAs), sister-chromatid exchanges (SCEs), micronucleus (MN) and comet assays. Lymphocytes were treated with negative control (sterile distilled water), positive control (MMC for cultured lymphocytes, and H(2)O(2) for isolated lymphocytes) and four concentrations (125, 250, 500, and 1000 microg/ml) of PS. According to the results, PS treatment significantly increases the CAs (with or without gaps at 500 and 1000 microg/ml concentrations) and SCEs (at 250, 500, 1000 microg/ml for 24h and 125, 250, 500, 1000 microg/ml for 48h) compared with vehicle control. Following treatment of the isolated lymphocytes for 1h, significant PS-induced DNA strand breaks were observed, at all concentrations. However, PS failed to significantly affect the MN assay. On the contrary, PS does not cause cell cycle delay as noted by the non-significant decrease in the cytokinesis-block proliferation index (CBPI) and replicative index (RI). Only a slight decrease was observed in the mitotic index (MI) at the highest concentration for both treatment times. From the results, PS is clearly seen to be genotoxic to the human peripheral blood lymphocytes in vitro. Copyright (c) 2009 Elsevier Ltd. All rights reserved.
The Fukushima Dai-ichi release of radionuclides into ocean waters caused significant local and global concern regarding the spread of radioactive material. We report unequivocal evidence that Pacific bluefin tuna, Thunnus orientalis, transported Fukushima-derived radionuclides across the entire North Pacific Ocean. We measured γ-emitting radionuclides in California-caught tunas and found 134Cs (4.0 ± 1.4 Bq kg−1) and elevated 137Cs (6.3 ± 1.5 Bq kg−1) in 15 Pacific bluefin tuna sampled in August 2011. We found no 134Cs and background concentrations (∼1 Bq kg−1) of 137Cs in pre-Fukushima bluefin and post-Fukushima yellowfin tunas, ruling out elevated radiocesium uptake before 2011 or in California waters post-Fukushima. These findings indicate that Pacific bluefin tuna can rapidly transport radionuclides from a point source in Japan to distant ecoregions and demonstrate the importance of migratory animals as transport vectors of radionuclides. Other large, highly migratory marine animals make extensive use of waters around Japan, and these animals may also be transport vectors of Fukushima-derived radionuclides to distant regions of the North and South Pacific Oceans. These results reveal tools to trace migration origin (using the presence of 134Cs) and potentially migration timing (using 134Cs:137Cs ratios) in highly migratory marine species in the Pacific Ocean.
Persistent organic pollutants (POPs) exert harmful effects on cognitive, endocrine and immune functions and bioaccumulate in the environment and human tissues. The aim of this study was to investigate the body burden of several POPs in the adult population (n=246) and their association to diet and other lifestyle factors in a Swedish national survey. Serum concentrations of several polychlorinated biphenyls (PCBs), and the pesticides hexachlorobenzene (HCB), β-hexachlorocyclohexane (β-HCH), chlordane compounds and dichlorodiphenyldichloroethylene (DDE) were determined by liquid-liquid extraction, silica column cleanup and gas chromatography high resolution mass spectrometry. Diet was assessed using 4-day food records and complementary dietary and lifestyle factors by questionnaire. Fish intake was additionally assessed by plasma fatty acid composition. Clustering of the compounds revealed that PCBs were separated into two clusters, one including low-chlorinated PCB 28 and 52, and the other high-chlorinated mono- and di-ortho PCBs, suggesting similarities and dissimilarities in exposure sources and possibly also toxicokinetics. Men had 24% and 32% higher levels of PCB 138-180 and chlordane compounds, respectively, compared with women. This may partly be explained by elimination of the POPs among women reporting a history of breastfeeding. The proportion of very long-chain n-3 fatty acids in plasma were positively correlated with the pollutants: r=0.24 (PCB 28), r=0.33 (PCB 118), r=0.35 (PCB 138-180), r=0.29 (HCB), r=0.18 (β-HCH), r=0.34 (chlordane compounds), r=0.34 (p,p'-DDE), p≤0.005. Individuals consuming fatty Baltic fish≥1 time per months had 45% higher serum levels of PCB 118 compared with non-consumers. Levels of PCB 28 were associated with the age of the residential building. To conclude, the population-distributed approach of surveying dietary habits, lifestyle factors and POP body burdens, made it possible to identify personal characteristics associated with the POP body burdens in Sweden. Copyright © 2012 Elsevier Ltd. All rights reserved.