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Maternal serum lead level during pregnancy is positively correlated with risk of preterm birth in a Chinese population Texto completo
2017
Li, Jun | Wang, Hua | Hao, Jia-Hu | Chen, Yuan-Hua | Liu, Lu | Yu, Zhen | Fu, Lin | Tao, Fang-Biao | Xu, De-Xiang
Lead (Pb) is a well-known developmental toxicant. The aim of the present study was to analyze the association between maternal serum Pb level and risk of preterm birth in a population-based birth cohort study. The present study analyzed a sub-study of the China-Anhui Birth Cohort that recruited 3125 eligible mother-and-singleton-offspring pairs. Maternal serum Pb level was measured by graphite furnace atomic absorption spectrometry. All subjects were classified into three groups by tertile division according to serum Pb level: Low-Pb (L-Pb, <1.18 μg/dl), Medium-Pb (M-Pb, 1.18–1.70 μg/dl), and High-Pb (H-Pb, ≥1.71 μg/dl). The rate of preterm birth was 2.8% among subjects with L-Pb, 6.1% among subjects with M-Pb, and 8.1% among subjects with H-Pb, respectively. After controlling confounding factors, the adjusted OR for preterm birth was 2.33 (95%CI: 1.49, 3.65) among subjects with M-Pb and 3.09 (95%CI: 2.01, 4.76) among subjects with H-Pb. Of interest, maternal Pb exposure in early gestational stage than in middle gestational stage was more susceptible to preterm birth. Moreover, maternal serum Pb level was only associated with increased risk of late preterm birth. The present study provides evidence that maternal serum Pb level during pregnancy is positively associated with risk of preterm birth in a Chinese population.
Mostrar más [+] Menos [-]Determining potential adverse effects in marine fish exposed to pharmaceuticals and personal care products with the fish plasma model and whole-body tissue concentrations Texto completo
2017
Meador, James P. | Yeh, Andrew | Gallagher, Evan P.
The Fish Plasma Model (FPM) was applied to water exposure and tissue concentrations in fish collected from two wastewater treatment plant impacted estuarine sites. In this study we compared predicted fish plasma concentrations to Cmax values for humans, which represents the maximum plasma concentration for the minimum therapeutic dose. The results of this study show that predictions of plasma concentrations for a variety of pharmaceutical and personal care products (PPCPs) from effluent concentrations resulted in 37 compounds (54%) exceeding the response ratio (RR = Fish [Plasma]/1%Cmaxtotal) of 1 compared to 3 compounds (14%) detected with values generated with estuarine receiving water concentrations. When plasma concentrations were modeled from observed whole-body tissue residues, 16 compounds out of 24 detected for Chinook (67%) and 7 of 14 (50%) for sculpin resulted in an RRtissue value greater than 1, which highlights the importance of this dose metric over that using estuarine water. Because the tissue residue approach resulted in a high percentage of compounds with calculated response ratios exceeding a value of unity, we believe this is a more accurate representation for exposure in the field. Predicting plasma concentrations from tissue residues improves our ability to assess the potential for adverse effects in fish because exposure from all sources is captured. Tissue residues are also more likely to represent steady-state conditions compared to those from water exposure because of the inherent reduction in variability usually observed for field data and the time course for bioaccumulation. We also examined the RR in a toxic unit approach to highlight the importance of considering multiple compounds exhibiting a similar mechanism of action.
Mostrar más [+] Menos [-]Anthropogenic noise alters dwarf mongoose responses to heterospecific alarm calls Texto completo
2017
Morris-Drake, Amy | Bracken, Anna M. | Kern, Julie M. | Radford, Andrew N.
Anthropogenic noise is an evolutionarily novel and widespread pollutant in both terrestrial and aquatic habitats. Despite increasing evidence that the additional noise generated by human activities can affect vocal communication, the majority of research has focused on the use of conspecific acoustic information, especially sexual signals. Many animals are known to eavesdrop on the alarm calls produced by other species, enhancing their likelihood of avoiding predation, but how this use of heterospecific information is affected by anthropogenic noise has received little empirical attention. Here, we use two field-based playback experiments on a habituated wild population of dwarf mongooses (Helogale parvula) to determine how anthropogenic noise influences the response of foragers to heterospecific alarm calls. We begin by demonstrating that dwarf mongooses respond appropriately to the alarm calls of sympatric chacma baboons (Papio ursinus) and tree squirrels (Paraxerus cepapi); fleeing only to the latter. We then show that mongoose foragers are less likely to exhibit this flee response to tree squirrel alarm calls during road-noise playback compared to ambient-sound playback. One explanation for the change in response is that noise-induced distraction or stress result in maladaptive behaviour. However, further analysis revealed that road-noise playback results in increased vigilance and that mongooses showing the greatest vigilance increase are those that do not subsequently exhibit a flee response to the alarm call. These individuals may therefore be acting appropriately: if the greater gathering of personal information indicates the absence of an actual predator despite an alarm call, the need to undertake costly fleeing behaviour can be avoided. Either way, our study indicates the potential for anthropogenic noise to interfere with the use of acoustic information from other species, and suggests the importance of considering how heterospecific networks are affected by this global pollutant.
Mostrar más [+] Menos [-]Abundance of antibiotics, antibiotic resistance genes and bacterial community composition in wastewater effluents from different Romanian hospitals Texto completo
2017
Szekeres, Edina | Baricz, Andreea | Chiriac, Cecilia Maria | Farkas, Anca | Opris, Ocsana | Soran, Maria-Loredana | Andrei, Adrian-Stefan | Rudi, Knut | Balcázar, José Luis | Dragoș, Nicolae | Coman, Cristian
Antimicrobial resistance represents a growing and significant public health threat, which requires a global response to develop effective strategies and mitigate the emergence and spread of this phenomenon in clinical and environmental settings. We investigated, therefore, the occurrence and abundance of several antibiotics and antibiotic resistance genes (ARGs), as well as bacterial community composition in wastewater effluents from different hospitals located in the Cluj County, Romania. Antibiotic concentrations ranged between 3.67 and 53.05 μg L−1, and the most abundant antibiotic classes were β-lactams, glycopeptides, and trimethoprim. Among the ARGs detected, 14 genes confer resistance to β-lactams, aminoglycosides, chloramphenicol, macrolide-lincosamide-streptogramin B (MLSB) antibiotics, sulfonamides, and tetracyclines. Genes encoding quaternary ammonium resistance and a transposon-related element were also detected. The sulI and qacEΔ1 genes, which confer resistance to sulfonamides and quaternary ammonium, had the highest relative abundance with values ranging from 5.33 × 10−2 to 1.94 × 10−1 and 1.94 × 10−2 to 4.89 × 10−2 copies/16 rRNA gene copies, respectively. The dominant phyla detected in the hospital wastewater samples were Proteobacteria, Bacteroidetes, Firmicutes, and Actinobacteria. Among selected hospitals, one of them applied an activated sludge and chlorine disinfection process before releasing the effluent to the municipal collector. This conventional wastewater treatment showed moderate removal efficiency of the studied pollutants, with a 55–81% decrease in antibiotic concentrations, 1–3 order of magnitude lower relative abundance of ARGs, but with a slight increase of some potentially pathogenic bacteria. Given this, hospital wastewaters (raw or treated) may contribute to the spread of these emerging pollutants in the receiving environments. To the best of our knowledge, this study quantified for the first time the abundance of antibiotics and ARGs in wastewater effluents from different Romanian hospitals.
Mostrar más [+] Menos [-]Environmental exposure to polycyclic aromatic hydrocarbons (PAHs): The correlation with and impact on reproductive hormones in umbilical cord serum Texto completo
2017
Yin, Shanshan | Tang, Mengling | Chen, Fangfang | Li, Tianle | Liu, Weiping
Polycyclic aromatic hydrocarbons (PAHs) are a type of ubiquitous pollutant with the potential ability to cause endocrine disruption that would have an adverse health impact on the general population. To assess the maternal exposure to PAHs in neonates and evaluate the possible impact of PAHs on reproductive hormone levels, the concentration of PAHs and reproductive hormone levels in the umbilical cord serum of 98 mother-infant pairs in the Shengsi Islands were investigated. The median concentration of total PAHs was determined to be 164 (Inter-Quartile Range, IQR 93.6–267) ng g−1 lipid, and 68% of the PAHs were lower-molecule congeners. The highest level was found for pyrene (PYR) and naphthalene (NAP), which contributed 54.6% of all the PAHs present in the samples. The exposure to PAHs negatively affected estradiol (E2) and Anti-Mullerian hormones (AMH) and positively affected FSH in the umbilical cord serum. The result expanded the database of the human burden of PAHs and suggested that PAHs can act as a type of Endocrine-Disrupting Chemical (EDC). These results may help to understand the complex pathways involved in disorders of human reproductive health associated with prenatal exposure to PAHs.
Mostrar más [+] Menos [-]Seasonal variation and potential source regions of PM2.5-bound PAHs in the megacity Beijing, China: Impact of regional transport Texto completo
2017
Zhang, Yuepeng | Chen, Jing | Yang, Hainan | Li, Rongjia | Yu, Qing
Based on the 12-hour PM2.5 samples collected in an urban site of Beijing, sixteen PM2.5-bound Polycyclic Aromatic Hydrocarbons (PAHs) were measured to investigate the characteristics and potential source regions of particulate PAHs in Beijing. The study period included the summer period in July–August 2014, the APEC source control period during the Asia-Pacific Economic Cooperation (APEC) meeting in the first half of November 2014, and the heating period in the second half of November 2014. Compared to PM2.5, sum of 16 PM2.5-bound PAHs exhibited more significant seasonal variation with the winter concentration largely exceeding the summer concentration. Temperature appeared to be the most crucial meteorological factor during the summer and heating periods, while PM2.5-bound PAHs showed stronger correlation with relative humidity and wind speed during the APEC source control period. Residential heating significantly increased the concentrations of higher-ring-number (≥4) PAHs measured in PM2.5 fraction. Potential source contribution function (PSCF) and concentration weighted trajectory (CWT) analysis as well as the (3 + 4) ring/(5 + 6) ring PAH ratio analysis revealed the seasonal difference in the potential source area of PM2.5-bound PAHs in Beijing. Southern Hebei was the most likely potential source area in the cold season. Using black carbon (BC) and carbon monoxide (CO) as the PAH tracers, regional residential, transportation and industry emissions all contributed to the PAH pollution in Beijing.
Mostrar más [+] Menos [-]Organohalogenated contaminants in plasma and eggs of rockhopper penguins: Does vitellogenin affect maternal transfer? Texto completo
2017
Dehnhard, Nina | Jaspers, Veerle L.B. | Demongin, Laurent | Van den Steen, Evi | Covaci, Adrian | Pinxten, Rianne | Crossin, Glenn T. | Quillfeldt, Petra | Eens, Marcel | Poisbleau, Maud
Although many studies have investigated organohalogenated contaminants (OHCs) in yolk, little is known about the mechanisms and timing of transfer of OHCs from the female to the egg. Vitellogenin, a yolk precursor, has been suggested to play a role in this transport.We here report for the first time the temporal changes in OHC and an index of vitellogenin concentrations in female plasma from the pre-laying period to clutch completion in free-living birds: the southern rockhopper penguin (Eudyptes chrysocome chrysocome) breeding in the Falkland/Malvinas Islands. In addition, OHC concentrations in the corresponding clutches were analysed. OHC concentrations in female plasma and in the yolk of both the first (A-) and the second (B-)eggs followed a similar pattern, with hexachlorobenzene (HCB) > Σpolychlorinated biphenyls (PCBs) > Σdichlorodiphenyltrichloroethane (DDTs) > Σmethoxylated polybrominated diphenyl ethers (MeO-PBDEs) > Σchlordanes (CHLs) > Σpolybrominated diphenyl ethers (PBDEs) ≈ Σhexachlorocyclohexanes (HCHs). The higher concentrations of MeO-PBDEs compared to PBDEs indicate a diet containing naturally-produced MeO-PBDEs. All OHC compounds except for PBDEs increased from the pre-laying period to A-egg laying and subsequently declined from A-egg laying to B-egg laying, and female plasma vitellogenin showed the same pattern. For ΣPCBs and ΣMeO-PBDEs, we found positive correlations between female plasma during A-egg laying and both eggs, and for HCB between female plasma and A-eggs only. During pre-laying, only ΣMeO-PBDEs correlated between both eggs and female plasma, and no correlations between OHC concentrations in eggs and female plasma were found during B-egg laying, highlighting that maternal transfer of OHCs is time- and compound-specific. Finally, female vitellogenin concentrations did not significantly correlate with any OHC compounds in either female plasma or eggs, and our results therefore did not confirm the suggested role of vitellogenin in the maternal transfer of OHC molecules into their eggs.
Mostrar más [+] Menos [-]Assessment of hydrophobic organic contaminant availability in sediments after sorbent amendment and its complete removal Texto completo
2017
Wu, Yanwen | Cho, Yeo-Myoung | Luthy, Richard G. | Kim, Kibeum | Jung, Jihyeun | Gala, William R. | Choi, Yongju
Sorbents amended to sediments in situ for sequestration of hydrophobic organic contaminants (HOCs) may be swept away from the treated sites due to hydrodynamic forces applied to the sediment surface. The purpose of this study is to examine the possibility of recovery of HOC availability in sorbent-amended sediment after complete removal of the sorbent. Sediment contact with an easily separable model sorbent Tenax beads for 28 days in a slurry phase resulted in 74–98% reduction in polycyclic aromatic hydrocarbon and polychlorinated biphenyl availability compared to the untreated controls. HOC availability in the sorbent-treated sediment slightly increased by sorbent removal and after one month of mixing in a slurry phase because the slowly-desorbing HOC fraction was released and repartitioned back to the sediment, partially replenishing the rapidly-desorbing HOC fraction. However, HOC availability did not further increase during an extended mixing period of 12 months suggesting that the repartitioning process was not an infinite source. HOC availability after the 12-month post-treatment mixing for the sorbent-treated sediment was 53–97% lower than that of the untreated sediment because of the combined effect of HOC mass removal from sediment (with the sorbent) and incomplete recovery of available HOC fraction in the sorbent-treated sediment.
Mostrar más [+] Menos [-]Influences of TiO2 nanoparticles on dietary metal uptake in Daphnia magna Texto completo
2017
Tan, Cheng | Wang, Wen-Xiong
Increasing applications of titanium dioxide nanoparticles (nano-TiO2) have intensified the risk of environmental contamination. Since nano-TiO2 can absorb metals and be consumed as ‘food’ by zooplankton but also can interact with phytoplankton, they could significantly disturb the existing metal assimilation patterns. In the present study, we quantified the dietary assimilation of Cd and Zn from nano-TiO2 and algae (Chlamydomonas reinhardtii) at comparable particle concentrations as well as in complex food environment (variable food quality and quantity) in a freshwater zooplankton Daphnia magna using the radiotracer technique. For both nano-TiO2 and algae as food, the feeding food quality and depuration food quantity significantly affected the assimilation efficiencies (AEs) of Cd and Zn. At feeding food quantity of 1 mg/L to 10 mg/L without food in depuration, the AEs of Cd and Zn from nano-TiO2 were lower than those from algae. When food was added during depuration, the influences of nano-TiO2 on metal AEs were variable due to the differential effects of food quantity on the gut passage of nano-TiO2 and algae. Furthermore, mixed nano-TiO2 and algae had the lowest metal AEs compared to sole nano-TiO2 or algae as a result of interaction between nano-TiO2 and algae during feeding. Overall, this study showed the distinguishing metal AEs between nano-TiO2 and algae, and that nano-TiO2 could significantly reduce the existing metal AEs from algae. More attention should be paid to the potential roles of nano-TiO2 in disturbing metal assimilation in the environmental risk assessments of nanoparticles.
Mostrar más [+] Menos [-]Regional transport, source apportionment and health impact of PM10 bound polycyclic aromatic hydrocarbons in Singapore's atmosphere Texto completo
2017
Urbančok, Dejan | Payne, Anthony J.R. | Webster, Richard D.
A study of 16 United States Environmental Protection Agency (USEPA) priority listed PAHs associated with particulate matter ≤ 10 μm (PM10) was conducted in Singapore during the period 29th May 2015 to 28th May 2016. The sampling period coincided with an extensive, regional smoke haze episode (5th September to 25th October) that occurred as a result of forest and peat fires in neighboring Indonesia. Throughout this study, 54 atmospheric PM10 samples were collected in 24 h periods using a high volume sampler (HVS) and quarts fiber filters (QFF) as the collection medium. Hysplit software for computing 3-D backward air mass trajectories, diagnostic ratio analysis and ring number distribution calculations were used to examine the sources of PAHs in the atmosphere in Singapore. Under normal conditions the total PAH concentrations were in a range from 0.68 ng m−3 to 3.07 ng m−3, while for the high haze period the results showed approximately double the concentrations with a maximum value of 5.97 ng m−3. Diagnostic ratio (DR) and principal component analysis (PCA) were conducted and indicated the contribution of the traffic as a dominant pyrogenic source of PAHs during normal periods, while results from the haze dataset showed relatively strong influence of smoke from peat and forest fires in Indonesia. Environmental and health risk from PAHs were assessed for both regular and hazy days.
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