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Exposure to acrylamide induces cardiac developmental toxicity in zebrafish during cardiogenesis
2018
Huang, Mengmeng | Jiao, Jingjing | Wang, Jun | Xia, Zhidan | Zhang, Yu
Acrylamide (AA), an environmental pollutant, has been linked to neurotoxicity, genotoxicity and carcinogenicity. AA is widely used to synthesize polymers for industrial applications, is widely found in Western-style carbohydrate-rich foods and cigarette smoke, and can also be detected in human umbilical cord blood and breast milk. This is the first study that demonstrated the cardiac developmental toxicity of AA in zebrafish embryos. Post-fertilization exposure to AA caused a clearly deficient cardiovascular system with a shrunken heart and abortive morphogenesis and function. Disordered expression of the cardiac genes, myl7, vmhc, myh6, bmp4, tbx2b and notch1b, as well as reduced number of myocardial cells and endocardial cells, indicated the collapsed development of ventricle and atrium and failed differentiation of atrioventricular canal (AVC). Although cell apoptosis was not affected, the capacity of cardiomyocyte proliferation was significantly reduced by AA exposure after fertilization. Further investigation showed that treatment with AA specifically reduced the expressions of nkx2.5, myl7 and vmhc in the anterior lateral plate mesoderm (ALPM) during the early cardiogenesis. In addition, AA exposure disturbed the restricted expressions of bmp4, tbx2b and notch1b during atrioventricular (AV) valve development and cardiac chambers maturation. Our results showed that AA-induced cardiotoxicity was related to decreased cardiac progenitor genes expression, reduced myocardium growth, abnormal cardiac chambers morphogenesis and disordered AVC differentiation. Our study demonstrates that AA exposure during a time point analogous to the first trimester in humans has a detrimental effect on early heart development in zebrafish. A high ingestion rate of AA-containing products may be an underlying risk factor for cardiogenesis in fetuses.
Show more [+] Less [-]Detection of glyphosate residues in companion animal feeds
2018
Zhao, Jiang | Pacenka, Steven | Wu, Jing | Richards, Brian K. | Steenhuis, Tammo | Simpson, Kenneth | Hay, Anthony G.
The widespread adoption of genetically modified, glyphosate-tolerant corn and soybean varieties in US crop production has led to a dramatic increase in glyphosate usage. Though present at or below regulatory limits currently set for human foodstuffs, the concentration of glyphosate in companion animal feed is currently unknown. In the present study, 18 commercial companion animal feeds from eight manufacturers were analyzed for glyphosate residues using ELISA. Every product contained detectable glyphosate residues in the range of 7.83 × 10¹–2.14 × 10³ μg kg⁻¹ dry weight, with the average and medians being 3.57 × 10² and 1.98 × 10² μg kg⁻¹ respectively. Three products were tested for within-bag variation and six were tested for lot to lot variation. Little within-bag variation was found, but the concentration of glyphosate varied by lot in half of the products tested. Glyphosate concentration was significantly correlated with crude fiber content, but not crude fat or crude protein. Average daily intakes by animals consuming feeds containing the median glyphosate concentration are estimated to result in exposures that are 0.68–2.5% of the Allowable Daily Intake (ADI) for humans in the US and EU, which are 1750 and 500 μg kg⁻¹ respectively. Consumption of the most contaminated feed, however, would result in exposure to 7.3% and 25% of the above ADIs, though the relevance of such an exposure to companion animals is currently unknown.Companion animal feeds contained 7.83 × 10¹–2.14 × 10³ μg kg⁻¹ glyphosate which is likely to result in pet exposure that is 4–12 times higher than that of humans on a per Kg basis.
Show more [+] Less [-]Environmental and lifestyle factors affecting exposure to polycyclic aromatic hydrocarbons in the general population in a Middle Eastern area
2018
Hoseini, Mohammad | Nabizadeh, Ramin | Delgado-Saborit, Juana Maria | Rafiee, Ata | Yaghmaeian, Kamyar | Parmy, Saeid | Faridi, Sasan | Hassanvand, Mohammad Sadegh | Yunesian, Masud | Naddafi, Kazem
The aim of this study was to investigate environmental and lifestyle factors affecting exposure to PAHs in the general population in a large city of the Middle East (Tehran) by measuring urinary monohydroxy polycyclic aromatic hydrocarbons (OH-PAHs) and establishing relationships between PAHs exposure and related factors. Urine samples were collected from 222 randomly chosen subjects who were living in the urban area of Tehran, Iran. Subjects were required to complete a detailed questionnaire aimed to document their personal and sociodemographic information, activities, cooking-related appliances, smoking history/exposure, and consumed foodstuff. Identification and quantification of six OH-PAHs was carried out using a gas chromatography with mass spectrometry (GC-MS). The geometric means for 1-OHP, 1-NAP, 2-NAP, 2-FLU, 9-FLU, and 9-PHE for whole population study were 310, 1220, 3070, 530, 330, and 130 ng/g creatinine, respectively. The two naphthalene metabolites contributed on average 77% of the total concentration of six measured OH-PAHs, followed by the 2-FLU, 1-OHP, 9-FLU, and 9-PHE. The most important predictors of urinary PAHs were consumption of grilled/barbecued foods, smoking, and exposure to environmental tobacco smoking. Water pipe smoking was linked to urinary OH-PAH metabolite in a dose-response function. Residential traffic was also related with OH-PAH metabolite concentrations. Other factors including gender, age, exposure to common house insecticides, open burning, and candle burning were found to be statistically associated with the urinary levels of some OH-PAHs. High exposure to PAHs among general population in Middle Eastern large cities and its associated health implications calls for public health measures to reduce PAHs exposure.
Show more [+] Less [-]Environmental concentrations and toxicology of 2,4,6-tribromophenol (TBP)
2018
Koch, Christoph | Sures, Bernd
2,4,6-Tribromophenol is the most widely produced brominated phenol. In the present review, we summarize studies dealing with this substance from an environmental point of view. We cover concentrations in the abiotic and biotic environment including humans, toxicokinetics as well as toxicodynamics, and show gaps of the current knowledge about this chemical.2,4,6-Tribomophenol occurs as an intermediate during the synthesis of brominated flame retardants and it similarly represents a degradation product of these substances. Moreover, it is used as a pesticide but also occurs as a natural product of some aquatic organisms. Due to its many sources, 2,4,6-tribromophenol is ubiquitously found in the environment. Nevertheless, not much is known about its toxicokinetics and toxicodynamics. It is also unclear which role the structural isomer 2,4,5-tribromophenol and several degradation products such as 2,4-dibromophenol play in the environment. Due to new flame retardants that enter the market and can degrade to 2,4,6-tribromophenol, this compound will remain relevant in future years – not only in aquatic matrices, but also in house dust and foodstuff, which are an important exposure route for humans.
Show more [+] Less [-]Interaction of melamine and di-(2-ethylhexyl) phthalate exposure on markers of early renal damage in children: The 2011 Taiwan food scandal
2018
Wu, Chia-Fang | Hsiung, Chao A. | Tsai, Hui-Ju | Tsai, Yi-Chun | Xie, Huimin | Chen, Bai-Hsiun | Wu, Ming-Tsang
Melamine and phthalate, mainly di-(2-ethylhexyl) phthalate (DEHP), are ubiquitously present in the general environment. We investigated whether urine melamine levels can modify the relationship between DEHP exposure and markers of early renal damage in children. A nationwide health survey for Children aged ≤12 years possibly exposed to phthalates were enrolled between August 2012 and January 2013. They were administered questionnaires to collect details regarding past DEHP exposure to phthalate-tainted foodstuffs. Urine samples were measured melamine levels, phthalate metabolites and biomarkers of renal damage, including urine microalbumin/creatinine ratio (ACR), N-acetyl-beta-d-glucosaminidase (NAG), and β2-microglobulin. The study included 224 children who had a median urine melamine level (μg/mmol creatinine) of 1.61 ranging 0.18–47.42. Positive correlations were found between urine melamine levels and urine ACR as well as urine NAG levels (both Spearman correlation coefficients r = 0.24, n = 224, p < .001). The higher the past DEHP exposure or urine melamine levels, the higher the prevalence of microalbuminuria. An interaction effect was also found between urine melamine levels and past DEHP exposure on urine ACR. Melamine levels may further modify the effect of past DEHP exposure on urine ACR in children.
Show more [+] Less [-]A critical review of selenium biogeochemical behavior in soil-plant system with an inference to human health
2018
Andrews, Martina | Shāhid, Muḥammad | Niazi, Nabeel Khan | Khalid, Sana | Murtaza, Behzad | Bibi, Irshad | Rashid, Muhammad Imtiaz
Selenium (Se) is an essential trace element for humans and animals, although controversial for different plant species. There exists a narrow line between essential, beneficial and toxic levels of Se to living organisms which greatly varies with Se speciation, as well as the type of living organisms. Therefore, it is crucial to monitor its solid- and solution-phase speciation, exposure levels and pathways to living organisms. Consumption of Se-laced food (cereals, vegetables, legumes and pulses) is the prime source of Se exposure to humans. Thus, it is imperative to assess the biogeochemical behavior of Se in soil-plant system with respect to applied levels and speciation, which ultimately affect Se status in humans. Based on available relevant literature, this review traces a plausible link among (i) Se levels, sources, speciation, bioavailability, and effect of soil chemical properties on selenium bioavailability/speciation in soil; (ii) role of different protein transporters in soil-root-shoot transfer of Se; and (iii) speciation, metabolism, phytotoxicity and detoxification of Se inside plants. The toxic and beneficial effects of Se to plants have been discussed with respect to speciation and toxic/deficient concentration of Se. We highlight the significance of various enzymatic (catalase, peroxidase, superoxide dismutase, ascorbate peroxidase, glutathione peroxidase) and non-enzymatic (phytochelatins and glutathione) antioxidants which help combat Se-induced overproduction of reactive oxygen species (ROS). The review also delineates Se accumulation in edible plant parts from soils containing low or high Se levels; elucidates associated health disorders or risks due to the consumption of Se-deficient or Se-rich foods; discusses the potential role of Se in different human disorders/diseases.
Show more [+] Less [-]Phthalates contamination in China: Status, trends and human exposure-with an emphasis on oral intake
2018
Wang, Wei | Leung, Anna Oi Wah | Chu, Lam Hang | Wong, Ming Hung
Despite the extensive production and use of phthalates in Asian countries, especially China, limited information is available about the current situation of human exposure in this region, and thus identification of further research needs is warranted. This review summarized the current trends of phthalates related to industrial production and human exposure by conducting a comprehensive assessment of phthalates contaminations in air, indoor dust, personal care products (PCPs), foodstuff and internal exposure in China, with comparisons with other countries. The concentrations of phthalates in indoor dust and PCPs in China were moderate, while concentrations in foods and air were among the highest worldwide. Dietary intake of phthalates varied with location, with hotspots in the southern and eastern coastal regions of China which correlated with the extensive industrial production recorded in these regions. This review firstly revealed the significantly differentiated food-type contribution profiles for phthalates in China and in other countries, which were affected by dietary habits and food contamination. The internal exposure for the Chinese population was found to be moderate, however there is a paucity of data available. Knowledge gaps identified concerning phthalates in China include trends in phthalates exposure, sources (e.g. PCPs, pharmaceuticals and medical treatment), and internal exposure derived from biomonitoring, warranting phthalates a research priority.
Show more [+] Less [-]Comparative feeding rates of native and invasive ascidians
2018
Hoxha, Tedi | Crookes, Steve | Lejeusne, Christophe | Dick, Jaimie T.A. | Chang, Xuexiu | Bouchemousse, Sarah | Cuthbert, Ross N. | MacIsaac, Hugh J.
Ascidians have a recent history of species introductions globally, often with strong ecological impacts. Comparisons of per capita effects of invaders and comparable natives are useful to assess such impacts. Here, we explore ingestion rates (IR) and clearance rates (CR) of Ciona intestinalis and Ciona robusta, co-occurring native and non-native ascidians, respectively, from Brittany, France. IR was positively related to food concentration, with the invader responding more strongly to increasing food concentration. CR also differed by species, with the invader demonstrating higher values. C. robusta exhibited a higher functional response (Type I) than did C. intestinalis (Type II). Relative impact measured using seasonal abundance and IR revealed that C. robusta has a much greater impact than C. intestinalis at all food concentrations tested, though the former has a constrained distribution which limits its regional impact. Nevertheless, when abundant, we expect C. robusta to exert a greater impact on algal foods.
Show more [+] Less [-]Heavy metal contamination and health risk assessment in three commercial fish species in the Persian Gulf
2018
Keshavarzi, Behnam | Hassanaghaei, Mina | Moore, Farid | Rastegari Mehr, Meisam | Soltanian, Siyavash | Lahijanzadeh, Ahmad Reza | Sorooshian, Armin
Five heavy metals/metalloids and related potential health risks were investigated in three commercially important fish species (Anodontostoma chacunda, Belangerii, and Cynoglossurs arel) in Musa Estuary and Mahshahr Harbour of the Persian Gulf. A total of 116 fish samples were collected, and their liver and muscle organs were separately analyzed using ICP-MS. Results revealed that studied metals concentrations (with some exceptions) varied among sampling stations, fish species and their organs. Human health risk is evaluated using different indices. The results indicated that arsenic and mercury are the most hazardous elements. Estimated daily intake (EDI) for the metals exceeded the provisional tolerable daily intake (PTDI) for all studied fish species. Also, target risk (TR) of arsenic indicated that consumption over a long period of time may result in a carcinogenic effect. The results are expected to create awareness among the public on the safety of consuming food products grown in particular areas.
Show more [+] Less [-]Characterization and quality assessment of recycled post-consumption poly(ethylene terephthalate) (PET)
2018
Masmoudi, Fatma | Fenouillot, Françoise | Mehri, Afef | Jaziri, Mohamed | Ammar, Emna
In the present study, the recycled post-consumption polyethylene terephthalate (PET) flakes were investigated as possible raw materials for the production of food packaging. After heating at 220 °C for 1 h, a steaming stage was conducted as a control test to assess the quality of the product. Different samples were characterized by ¹H-NMR, FT-IR, DSC/TGA analysis, viscosity index (VI), and trace metals analysis. The results showed that the recycled post-consumed PET flakes’ properties were generally conform to the standard norms of PET except the color of some flakes turned to yellow. Subsequently, a complementary study was undertaken to assess whether the material could be possibly reused for food packaging. For this purpose, rheological, thermal, and mechanical characterizations were performed. The results of the comparative study between the virgin and the recycled PET flakes concluded that the PET recycling affected the rheological properties but did not have any significant effect on their thermal and mechanical characteristics. Hence, it was deduced that the post-consumed PET flakes could be reused as a packaging material except food products.
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