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Surface water flooding, groundwater contamination, and enteric disease in developed countries: A scoping review of connections and consequences
2018
Andrade, L. | O'Dwyer, J. | O'Neill, E. | Hynds, P.
Significant volumes of research over the past four decades has sought to elucidate the social, infrastructural, economic, and human health effects of climate change induced surface flooding. To date, epidemiological and public health studies of flooding events have focused on mental health effects, vector-borne diseases, and infectious enteric disease due to floodwater contact (i.e. typically low consumption rates). The inherent nature of groundwater (i.e. out of sight, out of mind) and the widely held belief that aquifers represent a pristine source of drinking water due to natural attenuation may represent the “perfect storm” causing direct consumption of relatively large volumes of surface flood-contaminated groundwater. Accordingly, the current study sought to systematically identify and synthesize all available peer-reviewed literature pertaining to the nexus between surface flooding, groundwater contamination and human gastroenteric outcomes. Just 14 relevant studies were found to have been published during the period 1980–2017, thus highlighting the fact that this potentially significant source of climate-related exposure to environmental infection has remained understudied to date. Studies differed significantly in terms of type and data reporting procedures, making it difficult to discern clear trends and patterns. Approximately 945 confirmed cases of flood-related enteric disease were examined across studies; these concurred with almost 10,000 suspected cases, equating to approximately 20 suspected cases per confirmed case. As such, no regional, national or global estimates are available for the human gastrointestinal health burden of flood-related groundwater contamination. In light of the demonstrable public health significance of the concurrent impacts of groundwater susceptibility and climate change exacerbation, strategies to increase awareness about potential sources of contamination and motivate precautionary behaviour (e.g. drinking water testing and treatment, supply interruptions) are necessary. Mainstreaming climate adaptation concerns into planning policies will also be necessary to reduce human exposure to waterborne sources of enteric infection.
Mostrar más [+] Menos [-]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.
Mostrar más [+] Menos [-]Performance evaluation of Bacteroidales genetic markers for human and animal microbial source tracking in tropical agricultural watersheds
2018
Somnark, Pornjira | Chyerochana, Natcha | Mongkolsuk, Skorn | Sirikanchana, Kwanrawee
Microbial source tracking (MST) DNA-based assays have been used to successfully solve fecal pollution problems in many countries, particularly in developed nations. However, their application in developing countries has been limited but continues to increase. In this study, sixteen endpoint and quantitative PCR (qPCR) assays targeting universal and human-, swine-, and cattle-specific Bacteroidales gene markers were modified for endpoint PCR, evaluated for their performance with sewage and fecal samples from the Tha Chin watershed and subsequently validated with samples from the Chao Phraya watershed, Thailand. Sample sizes of 81 composite samples (from over 1620 individual samples) of farm animals of each type as well as 19 human sewage samples from the Tha Chin watershed were calculated using a stratified random sampling design to achieve a 90% confidence interval and an expected prevalence (i.e., desired assay's sensitivity) of 0.80. The best universal and human-, swine-, and cattle-specific fecal markers were BacUni EP, HF183/BFDrev EP, Pig-2-Bac EP, and Bac3 assays, respectively. The detection limits for these assays ranged from 30 to 3000 plasmid copies per PCR. The positive predictive values were high in universal and swine- and cattle-specific markers (85–100%), while the positive predictive value of the human-specific assay was 52.2%. The negative predictive values in all assays were relatively high (90.8–100%). A suite of PCR assays in Thailand was established for potential MST use in environmental waters, which supports the worldwide applicability of Bacteroidales gene markers. This study also emphasizes the importance of using a proper sample size in assessing the performance of MST markers in a new geographic region.
Mostrar más [+] Menos [-]Assessment of annual air pollution levels with PM1, PM2.5, PM10 and associated heavy metals in Algiers, Algeria
2018
Talbi, Abdelhamid | Kerchich, Yacine | Kerbachi, Rabah | Boughedaoui, Ménouèr
Concentrations of particulate matter less than 1 μm, 2.5 μm, 10 μm and their contents of heavy metals were investigated in two different stations, urban and roadside at Algiers (Algeria). Sampling was conducted during two years by a high volume samplers (HVS) equipped with a cascade impactor at four levels stage, for one year sampling. The characterization of the heavy metals associated to the particulate matter (PM) was carried out by X-Ray Fluorescence analysis (XRF). The annual average concentration of PM1, PM2.5 and PM10 in both stations were 18.24, 32.23 and 60.01 μg m⁻³ respectively. The PM1, PM2.5 and PM10 concentrations in roadside varied from 13.46 to 25.59 μg m⁻³, 20.82–49.85 μg m⁻³ and 45.90–77.23 μg m⁻³ respectively. However in the urban station, the PM1, PM2.5 and PM10 concentrations varied from 10.45 to 26.24 μg m⁻³, 18.53–47.58 μg m⁻³ and 43.8–91.62 μg m⁻³. The heavy metals associated to the PM were confirmed by Scanning Electron Microscopy-Energy Dispersive X-Ray analyses (SEM-EDX). The different spots of PM2.5 analysis by SEM-EDX shows the presence of nineteen elements with anthropogenic and natural origins, within the heavy metal detected, the lead was found with maximum of 5% (weight percent). In order to determine the source contributions of PM levels at the two sampling sites sampling, principal compound analysis (PCA) was applied to the collected data. Statistical analysis confirmed anthropogenic source with traffic being a significant source and high contribution of natural emissions. At both sites, the PM2.5/PM10 ratio is lower than that usually recorded in developed countries. The study of the back-trajectories of the air masses starting from Sahara shows that desert dust influences the concentration and the composition of the PM measured in Algiers.
Mostrar más [+] Menos [-]Environmental risk assessment of triclosan and triclocarban from personal care products in South Africa
2018
Musee, N.
Trends in the widespread use of personal care products (PCPs) containing triclosan (TCS) and triclocarban (TCC) have led to continuous emissions of these chemicals into the environment. Consequently, both chemicals are ubiquitously present at high concentrations in the aquatic systems based on widely reported measured environmental concentration (MECs) data in different environmental systems (e.g. freshwater) worldwide, especially in developed countries. In developing countries, however, lack of MECs data is a major issue, and therefore, inhibits effective risk assessment of these chemicals. Herein, TCS and TCC releases from personal care products (PCPs) were quantified, using a modelling approach to determine predicted environmental concentrations (PECs) in wastewater, freshwater, and soils, and likely risk(s) were estimated by calculating risk quotient (RQs). TCS and TCC in freshwater had RQs >1 based on estimated PECs with wide variations (≈2–232) as performed across the three dilutions factors (1, 3, and 10) considered in this study; an indicator of their likely adverse effect on freshwater organisms. In untreated and treated wastewater, TCS RQs values for bacteria were >1, but <1 for TCC, implying the former may adversely affect the functioning of wastewater treatment plants (WWTPs), and with no plausible impacts from the latter. In terrestrial systems, RQ results for individual chemicals revealed no or limited risks; therefore, additional investigations are required on their toxicity, as effects data was very limited and characterised by wide variations. Future national monitoring programs in developing countries should consider including TCS and TCC as the results suggest both chemicals are of concern to freshwater, and TCS in WWTPs. Potential risks of their metabolites remain unquantified to date.
Mostrar más [+] Menos [-]Tracing perfluoroalkyl substances (PFASs) in soils along the urbanizing coastal area of Bohai and Yellow Seas, China
2018
Meng, Jing | Wang, Tieyu | Song, Shuai | Wang, Pei | Li, Qifeng | Zhou, Yunqiao | Lü, Yonglong
With the shift of fluorine chemical industry from developed countries to China and increasing demand for fluorine chemical products, occurrence of perfluoroalkyl substances (PFASs) in production and application areas has attracted more attention. In this study, 153 soil samples were collected from 21 cities along the urbanizing coastal area of the Bohai and Yellow Seas. PFASs in this area were relatively higher, compared with other study areas. The concentrations ranged from 2.76 to 64.0 ng g−1, and those in most sites were between 2.76 and 13.9 ng g−1, with a predominance of perfluorooctanoic acid (PFOA) and perfluorooctane sulfonate (PFOS). Among the 21 coastal cities, contaminations of PFASs in Zibo, Nantong and Binzhou were elevated, which was likely affected by local fluorine chemical plants, equipment manufacturing and chemical industry, respectively. The total emissions of PFOA and PFOS were similar, with amount of 4431 kg and 4335 kg, respectively. Atmospheric deposition was the largest source, accounting for 93.2% of total PFOA and 69.6% of PFOS, respectively. In addition, due to application of aqueous film-forming foams (AFFFs) and sulfluramid, disposal of sewage sludge and stacking of solid waste, emission of PFOA and PFOS to soil was 1617 kg, accounting for 9.29% of the whole China. In general, pollution in Jiangsu, Shandong and Tianjin was more serious than those in Liaoning and Hebei, which was consistent with industrialization level and size of industrial sectors emitting PFASs.
Mostrar más [+] Menos [-]Perfluoroalkyl acids in surface seawater from the North Pacific to the Arctic Ocean: Contamination, distribution and transportation
2018
The bioaccumulative, persistent and toxic properties of long-chain perfluoroalkyl acids (PFAAs) resulted in strict regulations on PFAAs, especially in developed countries. Consequently, the industry manufacturing of PFAAs shifts from long-chain to short-chain. In order to better understand the pollution situation of PFAAs in marine environment under this new circumstance, the occurrence of 17 linear PFAAs was investigated in 30 surface seawater samples from the North Pacific to Arctic Ocean (123°E to 24°W, 32 to 82°N) during the sixth Chinese Arctic Expedition in 2014. Total concentrations of PFAAs (∑PFAAs) were between 346.9 pg per liter (pg/L) to 3045.3 pg/L. The average concentrations of ∑PFAAs decreased in the order of East China Sea (2791.4 pg/L, n = 2), Sea of Japan (East Sea) (832.8 pg/L, n = 6), Arctic Ocean (516.9 pg/L, n = 7), Chukchi Sea (505.2 pg/L, n = 4), Bering Sea (501.2 pg/L, n = 8) and Sea of Okhotsk (417.7 pg/L, n = 3). C4 to C9 perfluoroalkyl carboxylic acids (PFCAs) were detected in more than 80% of the surface water samples. Perfluorobutanoic acid (PFBA) was the most prevalent compound and perfluorooctanoic acid (PFOA) was the second abundant homolog. The concentration of individual PFAAs in the surface seawater of East China Sea was much higher than other sampling seas. As the spatial distribution of PFAAs in the marine environment was mainly influenced by the river inflow from the basin countries, which proved the large input from China. Furthermore, the marginal seas of China were found with the greatest burden of PFOA comparing the pollution level in surface seawater worldwide. PFBA concentration in the surrounding seas of China was also high, but distributed more evenly with an obvious increase in recent years. This large-scale monitoring survey will help the improvement and development of PFAAs regulations and management, where production shift should be taken into consideration.
Mostrar más [+] Menos [-]Collected marine litter — A growing waste challenge
2018
Schneider, Falk | Parsons, Sophie | Clift, Sally | Stolte, Andrea | McManus, Marcelle C.
Marine litter, in particular plastic debris, poses a serious threat to marine life, human health and the economy. In order to reduce its impact, marine litter collections such as beach clean-ups are frequently conducted. This paper presents a systematic review of temporal developments, geographical distribution, quantities and waste treatment pathways of collected marine litter. Results from over 130 studies and projects highlight the worldwide increase in collection efforts. Many of these are in wealthy countries that do not primarily contribute to the problem. Over 250 thousand tonnes, have already been removed, but there is little or no information available regarding how this waste is treated or used post collection. This paper highlights the need for a whole-system quantitative assessment for the collection and waste treatment of marine litter, and identifies the challenges associated with utilising this waste in the future.
Mostrar más [+] Menos [-]The nexus between energy consumption and financial development: estimating the role of globalization in Next-11 countries
2018
Danish, | Saud, Shah | Baloch, Muhammad Awais | Lodhi, Rab Nawaz
In the modern era of globalization, the economic activities expand with the passage of time. This expansion may increase demand for energy both in developing and developed countries. Therefore, this study assesses the impact of financial development on energy consumption incorporating the role of globalization in Next-11 countries. A group of panel estimation techniques is used to analyze the panel data and time series data for the time 1990–2014. The empirical results of the study suggest that financial development stimulates energy consumption. Also, globalization increases demand for energy consumption, although the single country analysis suggests that the effect of globalization on energy demand is heterogeneous among N-11 countries. Furthermore, feedback hypothesis is confirmed between financial development and energy consumption. Also, bidirectional causality is found between economic growth and energy consumption. The findings urge for the attention of policymaker in emerging countries to develop a strategy to reduce the consequences of energy consumption by controlling resource transfer through globalization to the host country and by adopting energy conversation policies.
Mostrar más [+] Menos [-]Are shocks to renewable energy consumption permanent or temporary? Evidence from 54 developing and developed countries
2018
Demir, Ender | Gözgor, Giray
The renewable energy sources are considered as the important factor to decrease the level of carbon emissions and to promote the global green economy. Understanding the dynamics of renewable energy consumption, this paper analyzes whether there is a unit root in renewable energy consumption in 54 countries over the period 1971–2016. To this end, the unit root test of Narayan–Popp with two endogenous (unknown) breaks is implemented. The paper finds that renewable energy consumption series are stationary around a level and the time trend in 45 of 54 countries. In other words, renewable energy consumption follows a unit root process only in nine countries: Brazil, China, Colombia, India, Israel, Japan, the Netherlands, Spain, and Turkey. The evidence implies that renewable energy demand policies, which aimed to decrease the carbon emissions, will only have permanent effects in those nine countries.
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