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Toxocara eggs in public places worldwide - A systematic review and meta-analysis Texto completo
2018
Fakhri, Y. | Gasser, R.B. | Rostami, A. | Fan, C.K. | Ghasemi, S.M. | Javanian, M. | Bayani, M. | Armoon, B. | Murādī, Bahrām
Toxocariasis is a neglected tropical disease of humans. Although many studies have indicated or shown that environmental contamination with Toxocara species eggs is a major risk factor for toxocariasis in humans, there has been no comprehensive analysis of published data or information. Here, we conducted the first systematic review and meta-analysis of current literature to assess the global prevalence of Toxocara eggs in public places (including beaches, parks and playgrounds). We conducted searches of the PubMed, Embase, Scopus and Science Direct databases for relevant studies published until 20 April 2018, and assessed the prevalence rates of Toxocara eggs in public places. We used the random effects model to calculate pooled prevalence estimates, with 95% confidence intervals (CIs), and analysed data in relation to WHO geographical regions. Subgroup analysis and meta-regressions regarding the geographical and environmental variables were also performed. Of 2384 publications identified, 109 studies that tested 42,797 soil samples in 40 countries were included in the meta-analysis. The pooled global prevalence of Toxocara eggs in public places was 21% (95% CI, 16–27%; 13,895/42,797). The estimated prevalence rates in the different WHO regions ranged from 13% to 35%: Western Pacific (35%; 95% CI, 15–58%), Africa (27%; 95% CI, 11–47%), South America (25%; 95% CI, 13–33%), South-East Asia (21%; 95% CI, 3–49%), Middle East and North Africa (18%; 95% CI, 11–24%), Europe (18%; 95% CI, 14–22%), and North and Central Americas (13%; 95% CI, 8–23%). A high prevalence was significantly associated with high geographical longitude (P = 0.04), low latitude (P = 0.02) and high relative environmental humidity (P = 0.04). This meta-analysis of data from published records indicates that public places are often heavily contaminated with eggs of Toxocara. This finding calls for measures to reduce the potential risk of infection and disease in humans.
Mostrar más [+] Menos [-]Plastic ingestion and trophic transfer between Easter Island flying fish (Cheilopogon rapanouiensis) and yellowfin tuna (Thunnus albacares) from Rapa Nui (Easter Island) Texto completo
2018
Chagnon, Catherine | Thiel, Martin | Antunes, Joana | Ferreira, Joana Lia | Sobral, Paula | Ory, Nicolas Christian
Millimetre-sized fragments have been documented in many fish species, but their transfer through food webs is still poorly understood. Here we quantified and described plastic fragments in the digestive tracts of 43 Easter Island flying fish (Cheilopogon rapanouiensis) and 50 yellowfin tunas (Thunnus albacares) from coastal waters around Rapa Nui (Easter Island) in the South Pacific subtropical gyre, and of fish preyed upon by T. albacares. Overall, seven C. rapanouiensis (16%) individuals had ingested microplastics, most of which resembled the common planktonic prey of the fish. One microplastic was found in the gut of a fish ingested by a tuna, which indicates that trophic transfer may occur between tuna and prey. A single T. albacares (2%) had ingested five mesoplastics (15.2–26.3 mm) that were probably not mistaken for prey items, but rather accidentally ingested during foraging on fish prey. The absence of microplastics in T. albacares suggests that such small particles, if transferred from the prey, do not accumulate in the relatively large digestive tract of large predators. On the other hand, larger plastic items may accumulate in the gut of tunas, to which they may induce deleterious effects that still need to be examined. However, only a small portion of the fish had ingested mesoplastics. The results of this study suggest that microplastic contamination is not an immediate threat to large predatory fish, such as T. albacares, along the coast of Easter Island within the South Pacific subtropical gyre.
Mostrar más [+] Menos [-]Use of green spaces and blood glucose in children; a population-based CASPIAN-V study Texto completo
2018
Dadvand, Payam | Poursafa, Parinaz | Heshmat, Ramin | Motlagh, Mohammad Esmaeil | Qorbani, Mostafa | Basagaña, Xavier | Kelishadi, Roya
A limited but emerging body of evidence is suggestive for a beneficial association between contact with green spaces and glucose homeostasis in adults; however, such an evidence for children is scarce. We evaluated the association between time spent in green spaces and fasting blood glucose (FBG) levels and impaired fasting glucose (IFG, FBG≥110 mg/dL) in a population-based multicentric sample of 3844 Iranian schoolchildren aged 7–18 years (2015). Participants were instructed to report the average hours per week spent in green spaces separately during each season and in each type of green space (parks, woods/other natural green spaces, and private gardens/agricultural field) for a 12-month period preceding the interview. We developed linear and logistic mixed effects models with centre as random effect to evaluate the association of time spent in green spaces (separately for each type as well as all types together) with FBG and IFG, respectively, controlled for a wide range of covariates including household indicators of socioeconomic status. We observed inverse associations between time spent in green spaces, especially in natural green spaces, and FBG levels. Specifically, 1.83 h increase in the total time spent in green spaces was associated with −0.5 mg/dl (95% confidence intervals: −0.9, −0.1) change in FBG levels. We also observed reduced risk of IFG associated with time spent in green spaces; however, the association was statistically significant only for the time spent in natural green spaces. There were suggestions for stronger associations for those residing in urban areas and those from lower socioeconomic status groups; however, the interaction terms for socioeconomic status and urbanity were not statistically significant. Further longitudinal studies are required to replicate our findings in other settings with different climates and population susceptibilities.
Mostrar más [+] Menos [-]Effects of long-term pig manure application on antibiotics, abundance of antibiotic resistance genes (ARGs), anammox and denitrification rates in paddy soils Texto completo
2018
Rahman, M Mizanur | Shan, Jun | Yang, Pinpin | Shang, Xiaoxia | Xia, Yongqiu | Yan, Xiaoyuan
Previous studies of long-term manure applications in paddy soil mostly focused on the effects on denitrification, occurrence of antibiotics and antibiotic resistance genes (ARGs) without considering the effects on anaerobic ammonium oxidation (anammox). Here, we investigated the potential rates of anammox and denitrification, occurrence of antibiotics and AGRs in response to three fertilization regimes (C, no fertilizer; N, mineral fertilizer; and NM, N plus pig manure) in six long-term paddy experiment sites across China. The potential rates of anammox (0.11–3.64 nmol N g−1 h−1) and denitrification (1.5–29.05 nmol N g−1 h−1) were correlated with the abundance of anammox genes (hzsB) and denitrification functional genes (narG, nirK, nirS and nosZ), respectively. The anammox and denitrification rates were affected by soil organic carbon (SOC) and significantly (p < 0.05) increased in NM treatments relative to those in N treatments. Although pig manure application increased antibiotic concentrations and abundance of ARGs compared with N treatments, the increased antibiotics did not directly affect the anammox and denitrification rates. Our results suggested that long-term pig manure application significantly increased antibiotic concentrations, abundance of ARGs, and rates of anammox and denitrification, and that the effects of pig manure-derived antibiotics on anammox and denitrification were marginal. This is the first report that investigates the effects of long-term pig manure application on anammox in paddy soils. More attention should be paid to the potential ecological risk of increased ARGs caused by pig manure application in paddy soils.
Mostrar más [+] Menos [-]Uptake of nicotine from discarded cigarette butts – A so far unconsidered path of contamination of plant-derived commodities Texto completo
2018
Selmar, Dirk | Radwan, Alzahraa | Abdalla, Neama | Taha, Hussein | Wittke, Carina | El-Henawy, Ahmed | Alshaal, Tarek | Amer, Megahed | Kleinwächter, Maik | Nowak, Melanie | El-Ramady, Hassan
This study aimed to elucidate the origin of the widespread nicotine contamination of plant-derived commodities, by conducting field experiments with various herbs and spice plants. By scattering tobacco and cigarette butts on the field and subsequent nicotine analyses of the acceptor plants, we verified that the alkaloid is leached out into the soil and is taken up by the crop plants. This path of contamination pertains even when there is only one cigarette butt per square meter. Even such minor pollution results - at least in the case of basil and peppermint - in considerable high nicotine contaminations, which exceed the maximum residue level by more than 20-fold.The data reported here clearly outline the large practical relevance of this soil-borne contamination path and imply that unthoughtful disposal of cigarette butts in the field by farm workers may be the reason for the widespread occurrence of nicotine contamination in plant-derived commodities. Therefore, such misbehavior needs to be prevented using education and sensitization, and by including this issue into the guidelines of good agricultural practice.
Mostrar más [+] Menos [-]Microplastics in the Arctic: A case study with sub-surface water and fish samples off Northeast Greenland Texto completo
2018
Scotti Morgana, Silvia | Ghigliotti, Laura | Estévez-Calvar, Noelia | Stifanese, Roberto | Wieckzorek, Alina | Doyle, Tom | Christiansen, Jørgen S. | Faimali, Marco | Garaventa, Francesca
The Arctic is a unique and fragile ecosystem that needs to be preserved and protected. Despite its remoteness, plastic pollution has been documented in this region. In the coming years, it is likely to worsen since, with climate changes and the opening of new shipping routes, the human presence is going to increase in the whole area. Here, we investigated the presence of microplastics (MPs) in sub-surface water and in two mid-trophic level Arctic fishes collected off Northeast Greenland: the demersal bigeye sculpin, Triglops nybelini, and the pelagic polar cod, Boreogadus saida. Plastics debris were found in the water samples at a concentration of 2.4 items/m³ ±0.8 SD which is higher than in most seas at lower latitudes. Both fish species had eaten MPs with different proportion among the species, 34% for T. nybelini (n = 71) and 18% for B. saida (n = 85). The significant difference in the occurrence of MPs between the two species is likely a consequence of their feeding behavior and habitat. Polyethylene was the main plastic polymer for water samples (41%, n = 17) and polyester (34%, n = 156) for fish samples as analyzed by Fourier Transformed Infrared (FT-IR) spectroscopy. Our data underscore that the Arctic regions are turning into a hotspot for plastic pollution, and this calls urgently for precautionary measures.
Mostrar más [+] Menos [-]Contamination, potential mobility, and origins of lead in sediment cores from the Shima River, south China Texto completo
2018
Gao, Lei | Li, Shaoheng | Wang, Zhuowei | Liang, Zuobing | Chen, Jianyao | Liang, Bin
Identifying contamination sources of environmental media and revealing their changing trends over time is useful for regional contamination control and environmental improvements. Four sediment cores (S1−S4) were collected from the Shima River to determine lead (Pb) concentrations, geochemical fractions and isotopic compositions, as well as the geochronology of core S3. The results show that Pb concentrations decreased from the upper and middle reach sites (means: 57.6, 95.9, and 97.6 mg kg⁻¹, respectively) to the lower reach site (43.8 mg kg⁻¹), resulting in a minimal to moderate enrichment in the sediments; enrichment increased due to anthropogenic Pb inputs at the river middle reach site since the 1990s. Sediment Pb in the geochemical fractions followed a decreasing order of reducible (47.3%) > residual (37.8%) > oxidizable (11.2%) > acid-soluble fraction (3.68%), exhibiting high mobility, further verifying the anthropogenic inputs. A descending trend in the ²⁰⁶Pb/²⁰⁷Pb ratio of the top sediments was the result of anthropogenic activities. In the present study, coal combustion, which was the major anthropogenic Pb source determined by its isotopic composition, contributed significantly (means: 18.4–60.6%) to sediment Pb based on a three end-members model. Less of a contribution (0–10.6%) was derived from vehicle exhaust. The increasing trend in the coal contribution was in accordance with that of the coal consumption in the study area. These results suggest that Pb contamination resulting from coal combustion has grown to become a major environmental issue in the study area.
Mostrar más [+] Menos [-]Influence of microplastic addition on glyphosate decay and soil microbial activities in Chinese loess soil Texto completo
2018
Yang, Xiaomei | Bento, Célia P.M. | Chen, Hao | Zhang, Hongming | Xue, Sha | Lwanga, Esperanza Huerta | Zomer, Paul | Ritsema, Coen J. | Geissen, Violette
The intensive use of pesticide and plastic mulches has considerably enhanced crop growth and yield. Pesticide residues and plastic debris, however, have caused serious environmental problems. This study investigated the effects of the commonly used herbicide glyphosate and micrometre-sized plastic debris, referred as microplastics, on glyphosate decay and soil microbial activities in Chinese loess soil by a microcosm experiment over 30 days incubation. Results showed that glyphosate decay was gradual and followed a single first-order decay kinetics model. In different treatments (with/without microplastic addition), glyphosate showed similar half-lives (32.8 days). The soil content of aminomethylphosphonic acid (AMPA), the main metabolite of glyphosate, steadily increased without reaching plateau and declining phases throughout the experiment. Soil microbial respiration significantly changed throughout the entirety of the experiment, particularly in the treatments with higher microplastic addition. The dynamics of soil β-glucosidase, urease and phosphatase varied, especially in the treatments with high microplastic addition. Particles that were considerably smaller than the initially added microplastic particles were observed after 30 days incubation. This result thus implied that microplastic would hardly affect glyphosate decay but smaller plastic particles accumulated in soils which potentially threaten soil quality would be further concerned especially in the regions with intensive plastic mulching application.
Mostrar más [+] Menos [-]Spatial variability of on-bicycle black carbon concentrations in the megacity of São Paulo: A pilot study Texto completo
2018
Targino, Admir Créso | Krecl, Patricia | Danziger Filho, João Edson | Segura, Julián Felipe | Gibson, Mark David
In 2015, a controversial bicycle lane was installed on Paulista Avenue –a thoroughfare in the heart of the megacity of São Paulo with a high rate of motorised vehicles. For the first time, on-bicycle air pollution concentrations were assessed along this lane using black carbon (BC) as an indicator of fossil fuel combustion. We measured BC concentrations with a hand-held microaethalometer at a high temporal resolution, enabling the capture of fine spatial gradients along the route. Although this new link expanded the city's cycling network, our pioneering study showed that BC concentrations were large (mean 8.5 μg m⁻³) with extreme values reaching 24.0 μg m⁻³, comparable to concentrations found in many megacities. In agreement with other studies, we observed that concentrations decreased about 1.6 times on a section of the bicycle lane running through a calmer neighbourhood, which could indicate the potential to safeguard the health of cyclists by installing lanes with greater separation from main roads, such as Paulista Avenue. This pilot work paves the way to more detailed studies aiming to map out the spatial distribution of other traffic-related pollutants across the city's 458-km long bicycle network.
Mostrar más [+] Menos [-]Suspect screening and non-targeted analysis of drinking water using point-of-use filters Texto completo
2018
Newton, Seth R. | McMahen, Rebecca L. | Sobus, Jon R. | Mansouri, Kamel | Williams, Antony J. | McEachran, Andrew D. | Strynar, Mark J.
Monitored contaminants in drinking water represent a small portion of the total compounds present, many of which may be relevant to human health. To understand the totality of human exposure to compounds in drinking water, broader monitoring methods are imperative. In an effort to more fully characterize the drinking water exposome, point-of-use water filtration devices (Brita® filters) were employed to collect time-integrated drinking water samples in a pilot study of nine North Carolina homes. A suspect screening analysis was performed by matching high resolution mass spectra of unknown features to molecular formulas from EPA's DSSTox database. Candidate compounds with those formulas were retrieved from the EPA's CompTox Chemistry Dashboard, a recently developed data hub for approximately 720,000 compounds. To prioritize compounds into those most relevant for human health, toxicity data from the US federal collaborative Tox21 program and the EPA ToxCast program, as well as exposure estimates from EPA's ExpoCast program, were used in conjunction with sample detection frequency and abundance to calculate a “ToxPi” score for each candidate compound. From ∼15,000 molecular features in the raw data, 91 candidate compounds were ultimately grouped into the highest priority class for follow up study. Fifteen of these compounds were confirmed using analytical standards including the highest priority compound, 1,2-Benzisothiazolin-3-one, which appeared in 7 out of 9 samples. The majority of the other high priority compounds are not targets of routine monitoring, highlighting major gaps in our understanding of drinking water exposures. General product-use categories from EPA's CPCat database revealed that several of the high priority chemicals are used in industrial processes, indicating the drinking water in central North Carolina may be impacted by local industries.
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