Instruct: Given a question, retrieve documents that answer the question.
Query: polyethylene plastic
Bisphenol A (BPA) and bisphenol B (BPB) concentrations were determined in peeled canned tomatoes of different brands bought in Italian supermarkets. Tomato samples analyzed were packaged in cans coated with either epoxyphenolic lacquer or low BADGE enamel. A solid phase extraction (SPE) was performed on C-18 Strata E cartridge followed by a step on Florisil cartridge. Detection and quantitation were performed by a reversed phase high-performance liquid chromatography (RP-HPLC) method with both UV and fluorescence detection (FD). On the total of 42 tested tomato samples, BPA was detected in 22 samples (52.4%), while BPB was detected in 9 samples (21.4%). BPA and BPB were simultaneously present in 8 of the analyzed samples. The levels of BPA found in this study are much lower than the European Union migration limits of 3 mg/kg food and reasonably unable to produce a daily intake exceeding the limit of 0.05 mg/kg body weight, established by European Food Safety Authority.
A polyphenol-rich (P-R) juice drink was developed as a potential approach to increase intake of dietary polyphenols. Analysis of the beverage by HPLC with PDA, fluorescence, and MS detection facilitated the identification/partial identification of 40 flavonoids and related phenolic compounds. The main constituents were (-)-epigallocatechin and other green tea flavan-3-ols, phloretin-2'-O-glucoside, gallic acid, hesperetin-7-O-rutinoside, 5-O-caffeoylquinic acid, and procyanidins, with trace levels of several flavonols and purple grape juice anthocyanins also being present. Healthy human subjects (n = 10) consumed 350 mL of the P-R juice drink, after which plasma and urine samples were collected over a 0-24 h period. HPLC-MS analysis identified 13 metabolites in plasma and a further 20 in urine. Qualitatively, the profiles of the glucuronide, sulfated, and methylated metabolites were very similar to those detected in earlier investigations when the main components in the juice drink were consumed separately in feeding studies with coffee, green tea, orange juice, and apple cider.
The exposure to some chemicals can lead to hormone disrupting effects. Presently, much attention is focused on so-called xeno-estrogens, synthetic compounds that interact with hormone receptors causing a number of reactions that eventually lead to effects related to reproduction and development. The current study was initiated to investigate the presence of a number of such compounds in precipitation as a follow-up on a previous study in which pesticide concentrations in air and precipitation were determined. Rainwater samples were collected at about 50 locations in The Netherlands in a four week period. The samples were analysed for bisphenol-A, alkylphenols and alkylphenol ethoxylates, phthalates, flame retardants and synthetic musk compounds. The results clearly indicated the presence of these compounds in precipitation. The concentrations ranged from the low ng l(-1) range for flame retardants to several thousands of ng l(-1) for the phthalates. Bisphenol-A was found in 30% of the samples in concentrations up to 130 ng l(-1), while alkylphenols and alkylphenol ethoxylates were found in virtually all locations in concentrations up to 920 ng l(-1) for the individual compounds. Phthalates were by far the most abundant xeno-estrogens in the precipitation samples and were found in every sample. Di-isodecyl phthalate was found in a surprisingly high concentration of almost 100 000 ng l(-1). Polybrominated flame retardants were found in the low ng l(-1) range and generally in less than 20% of the samples. Noticeable was the finding of hexabromocyclododecane, a replacement for the polybrominted diphenyl ethers at one location in a concentration of almost 2000 ng l(-1). Finally, as expected, synthetic musk compounds were detected in almost all samples. This is especially true for the polycyclic musks HHCB and AHTN. Nitro musks were found, but only on a few locations. Kriging techniques were used to calculate precipitation concentrations in between actual sampling locations to produce contour plots for a number of compounds. These plots clearly show located emission sources for a number of compounds such as bisphenol-A, nonylphenol ethoxylate, phthalates and AHTN. On the contrary, the results for HHCB and some phthalates indicated diffuse emission patterns, probably as the result of the use of consumer products containing these compounds.
Various pesticides are being used to destabilize, perturb, or inhibit crucial biochemical and physiological targets related to metabolism, growth, development, nervous communication, or behavior in pestiferous organisms. Chitin is an eukaryotic extracellular aminosugar biopolymer, massively produced by most fungal systems and by invertebrates, notably arthropods. Being an integral supportive component in fungal cell wall, insect cuticle, and nematode egg shell, chitin has been considered as a selective target for pesticide action. Throughout the elaborate processes of chitin formation and deposition, only the polymerization events associated with the cell membrane compartment are so far available for chemical interference. Currently, the actinomycetes-derived nucleoside peptide fungicides such as the polyoxins and the insecticidal benzoylaryl ureas have reached commercial pesticide status. The polyoxins and other structurally-related antibiotics like nikkomycins are strong competitive inhibitors of the polymerizing enzyme chitin synthase. The exact biochemical lesion inflicted by the benzoylaryl ureas is still elusive, but a post-polymerization event, such as translocation of chitin chains across the cell membrane, is suggested. Hydrolytic degradation of the chitin polymer is essential for hyphal growth, branching, and septum formation in fungal systems as well as for the normal molting of arthropods. Recently, insect chitinase activity was strongly and specifically suppressed by allosamidin, an actimomycetes-derived metabolite. In part, the defense mechanism in plants against invasion of pathogens is associated with induced chitinases. Chitin, chitosan, and their oligomers are able to act as elicitors which induce enhanced levels of chitinases in various plants. Lectins which bind to N-acetyl-D-glucosamine strongly interfere with fungal and insect chitin synthases. Plant lectins with similar properties may be involved in plant-pathogen interaction inter alia by suppressing fungal invasion.
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.
4-Nonylphenols (NPs) are common products of biodegradation of a widely used group of nonionic surfactants, the nonylphenol ethoxylates (NPEs). These compounds are known to be persistent, toxic, and estrogen active. There is a worldwide scientific and public discussion on the potential consequences of human long term dietary exposure to such endocrine disrupters. Despite numerous determinations of NPs in environmental samples no systematical reports exist relating to concentrations of NPs in food. We analyzed NPs in 60 different foodstuff commercially available in Germany. The results indicate that NPs are ubiquitous in food. The concentrations of NPs on a fresh weight basis varied between 0.1 and 19.4 microg/kg regardless of the fat content of the foodstuff. Based on data on German food consumption rates and these first analyses of NPs in food, the daily intake for an adult was calculated to be 7.5 microg/day NPs. For infants exclusively fed with breast milk or infant formulas daily intakes of 0.2 microg/day and 1.4 microg/day NPs, respectively, can be estimated.
SCOPE: Dietary polyphenols (PP) can be divided into two groups: extractable polyphenols (EPP) or compounds solubilized by aqueous organic solvents, and nonextractable polyphenols (NEPP) or compounds that remain in their corresponding extraction residues. Most studies on food polyphenols and dietary intakes address exclusively EPP. The objective of this work was to determine the actual amount of PP, including NEPP, in food and in a whole diet. METHODS AND RESULTS: HPLC-MS analyses were performed to identify EPP in methanol-acetone extracts and NEPP in the acidic hydrolyzates of their extraction residues in cereals, fruits, vegetables, nuts, and legumes. NEPP contents, estimated as hydrolyzable PP plus nonextractable proanthocyanidins (PA), ranged from 880 mg/100 g dry weight in fruits to 210 mg/100 g in cereals and were substantially higher than the contents of EPP. NEPP intake (day/person) in the Spanish diet (942 mg) is higher than EPP intake (258 mg) fruits and vegetables (746 mg) are the major contributors to the total PP intake (1201 mg). CONCLUSION: Non extractable polyphenols are the major part of dietary polyphenols. The knowledge of intakes and physiological properties of NEPP may be useful for a better understanding of the potential health effects of dietary PP.
BACKGROUND: Olive oil polyphenols have been associated with several cardiovascular health benefits. This study aims to examine the influence of a polyphenol-rich olive oil on blood pressure (BP) and endothelial function in 24 young women with high-normal BP or stage 1 essential hypertension. METHODS: We conducted a double-blind, randomized, crossover dietary-intervention study. After a run-in period of 4 months (baseline values), two diets were used, one with polyphenol-rich olive oil (∼30 mg/day), the other with polyphenol-free olive oil. Each dietary period lasted 2 months with a 4-week washout between diets. Systolic and diastolic BP, serum or plasma biomarkers of endothelial function, oxidative stress, and inflammation, and ischemia-induced hyperemia in the forearm were measured. RESULTS: When compared to baseline values, only the polyphenol-rich olive oil diet led to a significant (P < 0.01) decrease of 7.91 mm Hg in systolic and 6.65 mm Hg of diastolic BP. A similar finding was found for serum asymmetric dimethylarginine (ADMA) (-0.09 ± 0.01 µmol/l, P < 0.01), oxidized low-density lipoprotein (ox-LDL) (-28.2 ± 28.5 µg/l, P < 0.01), and plasma C-reactive protein (CRP) (-1.9 ± 1.3 mg/l, P < 0.001). The polyphenol-rich olive oil diet also elicited an increase in plasma nitrites/nitrates (+4.7 ± 6.6 µmol/l, P < 0.001) and hyperemic area after ischemia (+345 ± 386 perfusion units (PU)/sec, P < 0.001). CONCLUSIONS: We concluded that the consumption of a diet containing polyphenol-rich olive oil can decrease BP and improve endothelial function in young women with high-normal BP or stage 1 essential hypertension.
Most research studies in the field of dietary polyphenols or phenolic compounds use a chemical approach focusing exclusively on polyphenols extracted from plant foods with organic solvents. However, an appreciable part of polyphenols are not extracted with organic solvents and thus are ignored in biological, nutritional, and epidemiological studies. Recent studies have shown that these nonextractable polyphenols (NEPP) are a major part of total dietary polyphenols and that they exhibit a significant biological activity. A physiological approach is proposed on the basis that the bioavailability and health-related properties of polyphenols depend on their solubility in intestinal fluids, which is different from their solubility in organic solvents. This paper tries to clarify the concept of NEPP, distinguishing between chemical and physiological approaches and pointing out the main qualitative and quantitative differences between them. It is stressed that the literature and databases refer to only extractable polyphenols. Greater attention to NEPP may fill the current gap in the field of dietary polyphenols.
Background Phthalates are compounds that are used in a wide range of consumer products. However, the contribution of dietary intake to phthalate exposure has not been well defined. Objective The objective of this study was to assess the contribution of different food types to phthalate exposure. Phthalates are chemicals of concern because of the high levels measured in people and the environment, as well as the demonstrated toxicity in animal studies and limited epidemiological studies. Previous research, although limited, has suggested that phthalates contaminate food in various countries. Methods We conducted an exploratory analysis of data collected as part of the 2003–2004 National Health and Nutrition Examination Survey (NHANES). Associations between dietary intake (assessed by a 24-hr dietary recall) for a range of food types (meat, poultry, fish, fruit, vegetable, and dairy) and phthalate metabolites measured in urine were analyzed using multiple linear regression modeling. Results We found that metabolites of di-(2-ethylhexyl) phthalate (DEHP) and high-molecular-weight phthalate metabolites were associated with the consumption of poultry. Monoethyl phthalate, the metabolite of diethyl phthalate (DEP), was associated with vegetable consumption, specifically tomato and potato consumption. Discussion These results, combined with results from previous studies, suggest that diet is an important route of intake for phthalates. Further research is needed to determine the sources of food contamination with these toxic chemicals and to describe the levels of contamination of U.S. food in a large, representative U.S. sample.
Because of volatilization and leaching from their application in consumer and personal care products, phthalate esters are ubiquitous contaminants in the indoor environment. In this study, we measured concentrations and profiles of 9 phthalate esters in indoor dust samples collected from six cities in China (n = 75). For comparison, we also analyzed samples collected from Albany, New York, USA (n = 33). The results indicated that concentrations, except for dicyclohexyl phthalate (DCHP) and bis(2-ethylhexyl) phthalate (DEHP), and profiles of phthalate esters varied significantly between the two countries. Concentrations of diethyl phthalate (DEP), di-n-hexyl phthalate (DNHP), and benzyl butyl phthalate (BzBP) were 5 to 10 times higher in dust samples collected from Albany than those from the Chinese cities. In contrast, concentrations of di-iso-butyl phthalate (DIBP) in dust samples from Albany were 5 times lower than those from the Chinese cities. We estimated the daily intake (DI) of phthalate esters through the routes of dust ingestion and dermal dust absorption. The extent of contribution of indoor dust to human exposures varied, depending on the type of phthalate esters. The contribution of dust to DEHP exposure was 2-5% and 10-58% of the estimated total DIs in China and the USA, respectively. On the basis of the estimates of total DIs of phthalates, extrapolated from urinary metabolite concentrations, the contributions of inhalation, dermal absorption, and dietary intake to total DIs were estimated. The results indicated that dietary intake is the main source of exposure to DEHP (especially in China), whereas dermal exposure was a major source for DEP. This is the first study to elucidate sources of human exposure to phthalates among the general population in China.
Peanuts and peanut butter are commonly consumed as a snack, meal component and ingredient in various commercial products. Their consumption is associated with reduced CVD risk and they pose little threat to positive energy balance. However, questions have arisen as to whether product form (e.g. whole nut v. butter) and processing properties (e.g. roasting and adding flavours) may compromise their positive health effects. The present study investigated the effects of peanut form and processing on two CVD risk factors: fasting plasma lipids and body weight. One hundred and eighteen adults (forty-seven males and seventy-one females; age 29.2 (sd 8.4) years; BMI 30.0 (sd 4.5) kg/m2) from Brazil, Ghana and the United States were randomised to consume 56 g of raw unsalted (n 23), roasted unsalted (n 24), roasted salted (n 23) or honey roasted (n 24) peanuts, or peanut butter (n 24) daily for 4 weeks. Peanut form and processing did not differentially affect body weight or fasting plasma lipid responses in the total sample. However, HDL-cholesterol increased significantly at the group level, and total cholesterol, LDL-cholesterol and TAG concentrations decreased significantly in individuals classified as having elevated fasting plasma lipids compared with those with normal fasting plasma lipids. These observations suggest that the processing attributes assessed in this trial do not compromise the lipid-lowering effects of peanuts, and do not negatively impact body weight. Further studies are warranted to determine the effects of form and processing on other health risk factors.
Linaclotide (Linzess) for irritable bowel syndrome with constipation and for chronic idiopathic constipation.
Roundup is a glyphosate-based herbicide used worldwide, including on most genetically modified plants that have been designed to tolerate it. Its residues may thus enter the food chain, and glyphosate is found as a contaminant in rivers. Some agricultural workers using glyphosate have pregnancy problems, but its mechanism of action in mammals is questioned. Here we show that glyphosate is toxic to human placental JEG3 cells within 18 hr with concentrations lower than those found with agricultural use, and this effect increases with concentration and time or in the presence of Roundup adjuvants. Surprisingly, Roundup is always more toxic than its active ingredient. We tested the effects of glyphosate and Roundup at lower nontoxic concentrations on aromatase, the enzyme responsible for estrogen synthesis. The glyphosate-based herbicide disrupts aromatase activity and mRNA levels and interacts with the active site of the purified enzyme, but the effects of glyphosate are facilitated by the Roundup formulation in microsomes or in cell culture. We conclude that endocrine and toxic effects of Roundup, not just glyphosate, can be observed in mammals. We suggest that the presence of Roundup adjuvants enhances glyphosate bioavailability and/or bioaccumulation.
This study reviewed the literature on the relations between exposure to chemicals with endocrine-disrupting abilities and obesity in humans. The studies generally indicated that exposure to some of the endocrine-disrupting chemicals was associated with an increase in body size in humans. The results depended on the type of chemical, exposure level, timing of exposure and gender. Nearly all the studies investigating dichlorodiphenyldichloroethylene (DDE) found that exposure was associated with an increase in body size, whereas the results of the studies investigating polychlorinated biphenyl (PCB) exposure were depending on dose, timing and gender. Hexachlorobenzene, polybrominated biphenyls, beta-hexachlorocyclohexane, oxychlordane and phthalates were likewise generally associated with an increase in body size. Studies investigating polychlorinated dibenzodioxins and polychlorinated dibenzofurans found either associations with weight gain or an increase in waist circumference, or no association. The one study investigating relations with bisphenol A found no association. Studies investigating prenatal exposure indicated that exposure in utero may cause permanent physiological changes predisposing to later weight gain. The study findings suggest that some endocrine disruptors may play a role for the development of the obesity epidemic, in addition to the more commonly perceived putative contributors. © 2011 The Authors. obesity reviews © 2011 International Association for the Study of Obesity.
BACKGROUND: Plaque rupture and/or erosion is the leading cause of cardiovascular events; however, the process is not well understood. Although certain morphologic characteristics have been associated with ruptured plaques, these observations are of static histological images and not of the dynamics of plaque rupture. To elucidate the process of plaque rupture, we investigated the transformation of cholesterol from liquid to solid crystal to determine whether growing crystals are capable of injuring the plaque cap. HYPOTHESIS: We hypothesized that during cholesterol crystallization the spatial configuration rapidly changes, causing forceful expansion of sharp-edged crystals that can damage the plaque cap. METHODS: Two experiments were performed in vitro: first, cholesterol powder was melted in graduated cylinders and allowed to crystallize at room temperature. Volume changes from liquid to solid state were measured and timed. Second, thin biological membranes (20-40 microm) were put in the path of growing crystals to determine damage during crystallization. RESULTS: As cholesterol crystallized, the peak volume increased rapidly by up to 45% over 3 min and sharp-tipped crystals cut through and tore membranes. The amount of cholesterol and peak level of crystal growth correlated directly (r = 0.98; p < 0.01), as did the amount of cholesterol and rate of crystal growth (r = 0.99; p < 0.01). CONCLUSIONS: These observations suggest that crystallization of supersaturated cholesterol in atherosclerotic plaques can induce cap rupture and/or erosion. This novel insight may help in the development of therapeutic strategies that can alter cholesterol crystallization and prevent acute cardiovascular events.
Nonstarch polysaccharides (NSPs) occur naturally in many foods. The physiochemical and biological properties of these compounds correspond to dietary fiber. Nonstarch polysaccharides show various physiological effects in the small and large intestine and therefore have important health implications for humans. The remarkable properties of dietary NSPs are water dispersibility, viscosity effect, bulk, and fermentibility into short chain fatty acids (SCFAs). These features may lead to diminished risk of serious diet related diseases which are major problems in Western countries and are emerging in developing countries with greater affluence. These conditions include coronary heart disease, colo-rectal cancer, inflammatory bowel disease, breast cancer, tumor formation, mineral related abnormalities, and disordered laxation. Insoluble NSPs (cellulose and hemicellulose) are effective laxatives whereas soluble NSPs (especially mixed-link β-glucans) lower plasma cholesterol levels and help to normalize blood glucose and insulin levels, making these kinds of polysaccharides a part of dietary plans to treat cardiovascular diseases and Type 2 diabetes. Moreover, a major proportion of dietary NSPs escapes the small intestine nearly intact, and is fermented into SCFAs by commensal microflora present in the colon and cecum and promotes normal laxation. Short chain fatty acids have a number of health promoting effects and are particularly effective in promoting large bowel function. Certain NSPs through their fermented products may promote the growth of specific beneficial colonic bacteria which offer a prebiotic effect. Various modes of action of NSPs as therapeutic agent have been proposed in the present review. In addition, NSPs based films and coatings for packaging and wrapping are of commercial interest because they are compatible with several types of food products. However, much of the physiological and nutritional impact of NSPs and the mechanism involved is not fully understood and even the recommendation on the dose of different dietary NSPs intake among different age groups needs to be studied.
The prevalence of allergic diseases has increased in recent decades. Allergic diseases, particularly asthma, are complex diseases with strong gene-environment interactions. Epidemiological studies have identified a variety of risk factors for the development of allergic diseases. Among them, endocrine-disrupting chemicals (EDCs) play an important role in triggering or exacerbating these diseases. 4-Nonylphenol (NP) and 4-octylphenol (OP)--two major alkylphenols--have been recognized as common toxic and xenobiotic endocrine disrupters. Due to their low solubility, high hydrophobicity, and low estrogenic activity, they tend to accumulate in the human body and may be associated with the adverse effects of allergic diseases. Recently, new evidence has supported the importance of alkylphenols in the in vitro allergic response. This review focuses on the effects of alkylphenols on several key cell types in the context of allergic inflammation. Copyright © 2012. Published by Elsevier B.V.
A double-blind comparative study was conducted on cedar pollinosis patients in order to evaluate the treatment efficacy of apple polyphenol (Ap). Ap was administered (500 mg) once daily for 12 weeks, starting about 2 weeks prior to cedar pollen dispersion. Pollinosis symptoms during the study were evaluated according to the classification in the guidelines for allergic rhinitis diagnosis and treatment. The results show that the sneezing score was significantly lower for the Ap group than with the placebo group during the early period of pollen dispersion and during the main dispersion period. In addition, no adverse reactions were induced by Ap during the study. These results suggest that Ap may alleviate the symptoms of cedar pollinosis.
Erythritol, a naturally occurring polyol, is gaining attention as a bulk sweetener for human nutrition. Industrially, it is produced from glucose by fermentation. From various studies it is known to be non-cariogenic. Moreover, it is rapidly absorbed in the small intestine and quantitatively excreted in the urine. Only about 10 % enters the colon. Earlier in vitro experiments showed that erythritol remained unfermented for a fermentation period of 12 h. In order to investigate whether fresh human intestinal microbiota is able to adapt its enzyme activities to erythritol, a 24 h lasting fermentation was carried out under well-standardised in vitro conditions. For comparison maltitol, lactulose and blank (faecal inoculum only) were incubated as well. Fermentation patterns were established by following total gas production, hydrogen accumulation, changes in pH value, SCFA production and substrate degradation. Taking all fermentation parameters into account, erythritol turned out to be completely resistant to bacterial attack within 24 h, thus excluding an adaptation within that period. Since under in vivo conditions more easily fermentable substrates enter the colon continuously, it seems very unlikely that erythritol will be fermented in vivo.
Plants contain numerous polyphenols, which have been shown to reduce inflammation and hereby to increase resistance to disease. Examples of such polyphenols are isothiocyanates in cabbage and broccoli, epigallocatechin in green tee, capsaicin in chili peppers, chalones, rutin and naringenin in apples, resveratrol in red wine and fresh peanuts and curcumin/curcuminoids in turmeric. Most diseases are maintained by a sustained discreet but obvious increased systemic inflammation. Many studies suggest that the effect of treatment can be improved by a combination of restriction in intake of proinflammatory molecules such as advanced glycation end products (AGE), advanced lipoperoxidation end products (ALE), and rich supply of antiinflammatory molecules such as plant polyphenols. To the polyphenols with a bulk of experimental documentation belong the curcuminoid family and especially its main ingredient, curcumin. This review summarizes the present knowledge about these turmericderived ingredients, which have proven to be strong antioxidants and inhibitors of cyclooxigenase-2 (COX-2), lipoxygenase (LOX) and nuclear factor kappa B (NF-kappaB) but also AGE. A plethora of clinical effects are reported in various experimental diseases, but clinical studies in humans are few. It is suggested that supply of polyphenols and particularly curcuminoids might be value as complement to pharmaceutical treatment, but also prebiotic treatment, in conditions proven to be rather therapy-resistant such as Crohn's, long-stayed patients in intensive care units, but also in conditions such as cancer, liver cirrhosis, chronic renal disease, chronic obstructive lung disease, diabetes and Alzheimer's disease.
A human breast cancer cell line (MCF-7) was used to develop an in vitro screening assay for the detection of xenoestrogenic environmental pollutants. MCF-7 cells were cultured in DMEM containing 5% fetal bovine serum (FBS). An estrogenic response was defined as an increase in the frequency of proliferating MCF-7 cells, and was measured using a thymidine analog, bromodeoxyuridine, and flow cytometry. Di-2-ethylhexyl phthalate (DEHP) and 4-n-nonylphenol (4-n-NP) were used as model chemicals. The proliferation rate of S-phase cells after 24 h of exposure to various concentrations of 17beta-estradiol and to model compounds was compared with a positive and a negative control, containing 1 nM 17beta-estradiol and 0.1% ethanol, respectively. DEHP and 4-n-NP increased the frequency of proliferating MCF-7 cells in a dose-dependent manner. The lowest concentration that significantly increased the proliferation of MCF-7 cells was 10 microM for DEHP and 1 microM for 4-n-NP. The results showed that the assay is accurate and quick to perform. It may prove a valuable tool for screening potential estrogen-mimicking environmental pollutants.
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.
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.
The objective of this article is to review the epidemiologic literature examining the role of plant foods and plant-based diets in the prevention of childhood obesity. Available data suggest a protective effect of ready-to-eat cereal on risk of obesity, although prospective studies are still needed. Studies on fruit and vegetables; grains other than cereal; high-protein foods, including beans, legumes, and soy; fiber; and plant-based dietary patterns are inconsistent or generally null. The evidence base is limited, and most studies are fraught with methodologic limitations, including cross-sectional design, inadequate adjustment for potential confounders, and lack of consideration of reporting errors, stage of growth, and genetic influences. Well-designed prospective studies are needed. The lack of evidence showing an association between plant-based diets and childhood obesity does not mean that such diets should not be encouraged. Plant foods are highlighted in the Dietary Guidelines for Americans, and children do not meet the current recommendations for most plant foods. Although the advice to consume a plant-based, low-energy-dense diet is sound, ethical questions arise concerning the relatively high price of these diets in the United States and the way in which such diets are perceived in other parts of the world. Reducing the burden of childhood obesity, eliminating health disparities, and preventing the further spread of the disease around the globe will require not only policy interventions to ensure that plant foods are affordable and accessible to children of all income levels but also awareness of sociocultural norms that affect consumption.