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Seasonal variation of semen parameters correlates with environmental temperature and air pollution: A big data analysis over 6 years
2018
Santi, Daniele | Magnani, Elisa | Michelangeli, Marco | Grassi, Roberto | Vecchi, Barbara | Pedroni, Gioia | Roli, Laura | De Santis, Maria Cristina | Baraldi, Enrica | Setti, Monica | Trenti, Tommaso | Simoni, Manuela
Male fertility is progressively declining in many developed countries, but the relationship between male infertility and environmental factors is still unclear.To assess the influence of environmental temperature and air pollution on semen parameters, using a big-data approach.A big data analysis of parameters related to 5131 men, living in a province of Northern Italy and undergoing semen analyses between January 2010 and March 2016 was performed. Ambient temperature was recorded on the day of analysis and the 90 days prior to the analysis and the average value of particulate matter (PM) and NO2 in the year of the test. All data were acquired by geocoding patients residential address. A data warehouse containing 990,904,591 data was generated and analysed by multiple regressions.5573 semen analyses were collected. Both maximum and minimum temperatures registered on the day of collection were inversely related to total sperm number (p < .001), non-progressive motility (NPrM) (p < .005) and normal forms (p < .001). Results were confirmed considering temperature in the 30 and 60 days before collection, but not in the 90 days before collection. Total sperm number was lower in summer/autumn (p < .001) and was inversely related with daylight duration (p < .001). PM10 and PM2.5 were inversely related to PrM (p < .001 and p < .005) and abnormal forms (p < .001).This is the first evaluation of the relationship between male fertility-related parameters and environment using a big-data approach. A seasonal change in semen parameters was found, with a fluctuation related to both temperature and daylight duration. A negative correlation between air pollution and semen quality is suggested. Such seasonal and environmental associations should be considered when assessing changes of male fertility-related parameters over time.
Afficher plus [+] Moins [-]Surface O3 photochemistry over the South China Sea: Application of a near-explicit chemical mechanism box model
2018
Wang, Yu | Guo, Hai | Zou, Shichun | Lyu, Xiaopu | Ling, Zhenhao | Cheng, Hairong | Zeren, Yangzong
A systematic field measurement was conducted at an island site (Wanshan Island, WSI) over the South China Sea (SCS) in autumn 2013. It was observed that mixing ratios of O₃ and its precursors (such as volatile organic compounds (VOCs), nitrogen oxides (NOₓ = NO + NO₂) and carbon monoxide (CO)) showed significant differences on non-episode days and episode days. Additional knowledge was gained when a photochemical box model incorporating the Master Chemical Mechanism (PBM-MCM) was applied to further investigate the differences/similarities of O₃ photochemistry between non-episode and episode days, in terms of O₃-precursor relationship, atmospheric photochemical reactivity and O₃ production. The simulation results revealed that, from non-O₃ episode days to episode days, 1) O₃ production changed from both VOC and NOₓ-limited (transition regime) to VOC-limited; 2) OH radicals increased and photochemical reaction cycling processes accelerated; and 3) both O₃ production and destruction rates increased significantly, resulting in an elevated net O₃ production over the SCS. The findings indicate the complexity of O₃ pollution over the SCS.
Afficher plus [+] Moins [-]Blood concentrations of PCBs and DDTs in an avian predator endemic to southern Africa: Associations with habitat, electrical transformers and diet
2018
Garcia-Heras, Marie-Sophie | Arroyo, Beatriz | Simmons, Robert E. | Camarero, Pablo R. | Mateo, Rafael | Mougeot, Francois
Persistent pollutants such as organochlorine compounds (OCs) have been highlighted as a cause of population decline in avian predators. Understanding patterns of OCs contamination can be crucial for the conservation of affected species, yet little is known on these threats to African raptors. Here we report on OC concentrations in an endangered predator endemic to southern Africa, the Black Harrier Circus maurus. Blood samples were collected in 2012–2014 from wild nestlings (n = 90) and adults (n = 23) in south-western South Africa, where agriculture and urbanization have developed rapidly since the 1950s. Polychlorinated biphenyl (ΣPCB) and dichlorodiphenyltrichloroethane (ΣDDT, for p,p’-DDT + p,p’-DDE) were detected in 79% and 84% of sampled individuals, respectively, with varying concentrations among demographic groups: nestlings had significantly higher ΣPCB and p,p’-DDT concentrations than adults, while adults had higher levels of p,p’-DDE than nestlings. Levels of ΣPCB significantly increased with an index of electric transformer density, a measure of the number and power of electric transformers around active nests. We propose this index as a useful tool for assessing ΣPCB exposure risk in other wildlife. Levels of p,p’-DDE significantly increased with the proportion of wetlands within the breeding territory, and also with the proportion of bird biomass in the diet. No association was found between OC levels and the protected area status of nesting sites. Physiological effects of contaminants were also manifest in increased white blood cell counts with higher p,p’-DDT levels. Heterophil to lymphocyte ratio increased with higher ΣPCB levels, suggesting increased physiological stress and reduced immunity in contaminated individuals. Our results suggest that OCs are still a current cause of concern for endangered Black Harriers, as well as other sympatric predators.
Afficher plus [+] Moins [-]Metagenome enrichment approach used for selection of oil-degrading bacteria consortia for drill cutting residue bioremediation
2018
Guerra, Alaine B. | Oliveira, Jorge S. | Silva-Portela, Rita C.B. | Araújo, Wydemberg | Carlos, Aline C. | Vasconcelos, Ana Tereza R. | Freitas, Ana Teresa | Domingos, Yldeney Silva | de Farias, Mirna Ferreira | Fernandes, Glauber José Turolla | Agnez-Lima, Lucymara F.
Drill cuttings leave behind thousands of tons of residues without adequate treatment, generating a large environmental liability. Therefore knowledge about the microbial community of drilling residue may be useful for developing bioremediation strategies. In this work, samples of drilling residue were enriched in different culture media in the presence of petroleum, aiming to select potentially oil-degrading bacteria and biosurfactant producers. Total DNA was extracted directly from the drill cutting samples and from two enriched consortia and sequenced using the Ion Torrent platform. Taxonomic analysis revealed the predominance of Proteobacteria in the metagenome from the drill cuttings, while Firmicutes was enriched in consortia samples. Functional analysis using the Biosurfactants and Biodegradation Database (BioSurfDB) revealed a similar pattern among the three samples regarding hydrocarbon degradation and biosurfactants production pathways. However, some statistical differences were observed between samples. Namely, the pathways related to the degradation of fatty acids, chloroalkanes, and chloroalkanes were enriched in consortia samples. The degradation colorimetric assay using dichlorophenolindophenol as an indicator was positive for several hydrocarbon substrates. The consortia were also able to produce biosurfactants, with biosynthesis of iturin, lichnysin, and surfactin among the more abundant pathways. A microcosms assay followed by gas chromatography analysis showed the efficacy of the consortia in degrading alkanes, as we observed a reduction of around 66% and 30% for each consortium in total alkanes. These data suggest the potential use of these consortia in the bioremediation of drilling residue based on autochthonous bioaugmentation.
Afficher plus [+] Moins [-]Contaminants of emerging concern presence and adverse effects in fish: A case study in the Laurentian Great Lakes
2018
Jorgenson, Zachary G. | Thomas, Linnea M. | Elliott, Sarah M. | Cavallin, Jenna E. | Randolph, Eric C. | Choy, Steven J. | Alvarez, David A. | Banda, Jo A. | Gefell, Daniel J. | Lee, K. E. (Kathy E.) | Furlong, Edward T. | Schoenfuss, Heiko L.
The Laurentian Great Lakes are a valuable natural resource that is affected by contaminants of emerging concern (CECs), including sex steroid hormones, personal care products, pharmaceuticals, industrial chemicals, and new generation pesticides. However, little is known about the fate and biological effects of CECs in tributaries to the Great Lakes. In the current study, 16 sites on three rivers in the Great Lakes basin (Fox, Cuyahoga, and Raquette Rivers) were assessed for CEC presence using polar organic chemical integrative samplers (POCIS) and grab water samplers. Biological activity was assessed through a combination of in vitro bioassays (focused on estrogenic activity) and in vivo assays with larval fathead minnows. In addition, resident sunfish, largemouth bass, and white suckers were assessed for changes in biological endpoints associated with CEC exposure. CECs were present in all water samples and POCIS extracts. A total of 111 and 97 chemicals were detected in at least one water sample and POCIS extract, respectively. Known estrogenic chemicals were detected in water samples at all 16 sites and in POCIS extracts at 13 sites. Most sites elicited estrogenic activity in bioassays. Ranking sites and rivers based on water chemistry, POCIS chemistry, or total in vitro estrogenicity produced comparable patterns with the Cuyahoga River ranking as most and the Raquette River as least affected by CECs. Changes in biological responses grouped according to physiological processes, and differed between species but not sex. The Fox and Cuyahoga Rivers often had significantly different patterns in biological response Our study supports the need for multiple lines of evidence and provides a framework to assess CEC presence and effects in fish in the Laurentian Great Lakes basin.
Afficher plus [+] Moins [-]Lead-based paint in children's toys sold on China's major online shopping platforms
2018
Shen, Zhengtao | Hou, Deyi | Zhang, Ping | Wang, Yinan | Zhang, Yunhui | Shi, Peili | O'Connor, David
Lead in paint is a major public health concern and has drawn much attention from international organizations such as the World Health Organization (WHO) and the United Nations Environmental Programme (UNEP). However, there is limited research on lead-based paint, especially its use in toys, which poses an explicit health risk to vulnerable children. The present study sampled 100 different toys purchased from the three largest online shopping platforms in China: JD, Taobao (TB) and Tmall (TM). These selected toys have been sold nearly 3 million times in total, suggesting that they may have reached the dwellings of millions of children. It was found that the toys sold by JD and TM, which are considered organized sellers, had average lead concentrations of 25 mg/kg and 32 mg/kg, respectively, much lower than that of toys sold by unorganized sellers on the TB platform, at 219 mg/kg. Approximately 12% of the toys purchased from TB contained paint with total lead concentrations exceeding China's regulatory standard for paints in toy manufacturing, and nearly 36% of the toys purchased from TB exceeded the equivalent US regulatory standard and EU standard. These results suggest that further action is needed to verify the health and safety standards of toys sold by such unorganized sellers. Moreover, this study found that China's regulatory standard (90 mg/kg) based on soluble lead may underestimate the risk posed by lead in paints, and it is suggested that future regulatory thresholds for lead levels in paints for toy manufacture be based on total rather than soluble lead concentrations. The present study also explored various influencing factors on lead concentration, and found that lead concentrations were related to toy price, age group, color, and sales volume.
Afficher plus [+] Moins [-]Emission measurement of diesel vehicles in Hong Kong through on-road remote sensing: Performance review and identification of high-emitters
2018
Huang, Yuhan | Organ, Bruce | Zhou, John L. | Surawski, Nic C. | Hong, Guang | Chan, Edward F.C. | Yam, Yat Shing
A two-year remote sensing measurement program was carried out in Hong Kong to obtain a large dataset of on-road diesel vehicle emissions. Analysis was performed to evaluate the effect of vehicle manufacture year (1949–2015) and engine size (0.4–20 L) on the emission rates and high-emitters. The results showed that CO emission rates of larger engine size vehicles were higher than those of small vehicles during the study period, while HC and NO were higher before manufacture year 2006 and then became similar levels between manufacture years 2006 and 2015. CO, HC and NO of all vehicles showed an unexpectedly increasing trend during 1998–2004, in particular ≥6001 cc vehicles. However, they all decreased steadily in the last decade (2005–2015), except for NO of ≥6001 cc vehicles during 2013–2015. The distributions of CO and HC emission rates were highly skewed as the dirtiest 10% vehicles emitted much higher emissions than all the other vehicles. Moreover, this skewness became more significant for larger engine size or newer vehicles. The results indicated that remote sensing technology would be very effective to screen the CO and HC high-emitters and thus control the on-road vehicle emissions, but less effective for controlling NO emissions. No clear correlation was observed between the manufacture year and percentage of high-emitters for ≤3000 cc vehicles. However, the percentage of high-emitters decreased with newer manufacture year for larger vehicles. In addition, high-emitters of different pollutants were relatively independent, in particular NO emissions, indicating that high-emitter screening criteria should be defined on a CO-or-HC-or-NO basis, rather than a CO-and-HC-and-NO basis.
Afficher plus [+] Moins [-]Investigating a probable relationship between microplastics and potentially toxic elements in fish muscles from northeast of Persian Gulf
2018
Akhbarizadeh, Razegheh | Moore, Farid | Keshavarzi, Behnam
Although weekly consumption of fish is recommended, the presence of contaminants in seafood has raised many concerns regarding the benefits of fish intake. In the present study microplastics (MPs) and metals’ concentration in muscles of both benthic and pelagic fish species from northeast of Persian Gulf were investigated and the risk/benefit of their consumption was assessed. The results demonstrated that MPs and Hg in all species and Se in benthic species increase with size, while relationship between other metals, and fish size is not consistent. Consumption of a meal ration of 300 and < 100 g/week for adults and children, respectively, is recommended since it would provide the required essential elements with no human health risk. On the other hand, the estimated intake of MPs from fish muscles revealed that the mean intake of MPs for P. indicus, E. coioides, A. djedaba, and S. jello consumption is 555, 240, 233, and 169 items/300 g-week, respectively. Moreover, the relationship between MPs and metals in fish muscles were positive for A. djedaba, and negative for E. coioides. Considering the chemical toxicity of MPs and metals, and their good linear relationships in some species, consumption of high doses of the studied fish may pose a health threat to the consumers.
Afficher plus [+] Moins [-]Estimation of the soil hazardous concentration of methylparaben using a species sensitivity approach
2018
Kim, Dokyung | Cui, Rongxue | Moon, Jongmin | Kwak, Jin Il | Kim, Shin Woong | Kim, Dasom | An, Youn-Joo
Methylparaben, which is known to be an endocrine-disrupting chemical, is added to various personal care products, including cosmetics, and is also used as a food preservative and in pharmaceuticals. However, information on the toxicity of methylparaben in soil ecosystems is limited. Furthermore, unlike other substances such as metals and pesticides, there is no regulation of levels or safe concentrations of methylparaben in soil ecosystems. Therefore, the aims of this study were to evaluate the toxicity of methylparaben on soil species and to derive hazardous concentration (HC) values with respect soil ecosystem protection. We conducted acute bioassays on eight species within six taxonomic groups and chronic bioassays on five species within four taxonomic groups. On the basis of the results obtained, we derived an acute HC₅ value of 44 mg/kg soil and a corresponding chronic value of 27 mg/kg soil for methylparaben using species sensitivity distribution methodology following Australian and New Zealand guidelines. Given that there has been no proposed standard value for methylparaben in soil in any country, it was not possible to compare the HC values calculated in this study with regulation standard levels. Nevertheless, to our knowledge, this study is first to assess the toxicity of methylparaben against soil-inhabiting species and to estimate acute and chronic HCs for soil fauna and flora. The results of this study will provide valuable fundamental data for the establishment of acceptable levels of methylparaben in soil.
Afficher plus [+] Moins [-]Gut as a target for cadmium toxicity
2018
Tinkov, Alexey A. | Gritsenko, Viktor A. | Skalnaya, Margarita G. | Cherkasov, Sergey V. | Aaseth, Jan | Skalny, Anatoly V.
The primary objective of the present study was to review the impact of Cd exposure on gut microbiota and intestinal physiology, as well as to estimate whether gut may be considered as the target for Cd toxicity. The review is based on literature search in available databases. The existing data demonstrate that the impact of Cd on gut physiology is two-sided. First, Cd exposure induces a significant alteration of bacterial populations and their relative abundance in gut (increased Bacteroidetes-to-Firmicutes ratio), accompanied by increased lipopolysaccharide (LPS) production, reflecting changed metabolic activity of the intestinal microbiome. Second, in intestinal wall Cd exposure induces inflammatory response and cell damage including disruption of tight junctions, ultimately leading to increased gut permeability. Together with increased LPS production, impaired barrier function causes endotoxinemia and systemic inflammation. Hypothetically, Cd-induced increase gut permeability may also result in increased bacterial translocation. On the one hand, bacteriolysis may be associated with aggravation of endotoxemia. At the same time, together with Cd-induced impairment of macrophage inflammatory response, increased bacterial translocation may result in increased susceptibility to infections. Such a supposition is generally in agreement with the finding of higher susceptibility of Cd-exposed mice to infections. The changed microbiome metabolic activity and LPS-induced systemic inflammation may have a significant impact on target organs. The efficiency of probiotics in at least partial prevention of the local (intestinal) and systemic toxic effects of cadmium confirms the role of altered gut physiology in Cd toxicity. Therefore, probiotic treatment may be considered as the one of the strategies for prevention of Cd toxicity in parallel with chelation, antioxidant, and anti-inflammatory therapy.
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