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Public perception and health implication of loom-dye effluent irrigation on growth of rice (Oryza sativa L.) and red amaranth (Amaranthus tricolor L.) seedlings Full text
2020
Rahman, Md Arifur | Saha, Biplob Kumar | Chowdhury, Md Akhter Hossain | Chowdhury, Md Abul Khair | Mohiuddin, K. M.
Loom-dye effluent discharge has constituted a major environmental threat to the people of Belkuchi Upazila of Sirajganj District. The present study was conducted to characterize loom-dye effluents and investigate their health implications by the growth analysis of rice and red amaranth seedlings along with a survey study among the individuals associated with loom-dyeing, weaving, and crop farming activities. A total of twenty-eight loom-dye effluent samples were collected for physicochemical characterization; among them, only three loom-dye effluents, i.e. pink, violet, and black dyes, at concentrations of 0, 10, 25, 50, 75, and 100% were applied as irrigation water to rice and red amaranth. The plant growth experiment was laid out following a completely randomized design with three replicas. Chemical analyses of loom-dye effluents showed the presence of a significant amount of plant nutrients and heavy metals. The mean concentrations of Pb, Cd, Cr, Fe, Mn, Zn, and Cu were 0.938, 0.046, 0.212, 7.109, 0.609, 0.351, and 0.191 mg L⁻¹, respectively. Among the metals, the concentrations of Pb, Cr, Fe, and Mn were above the recommended limit proposed by the irrigation water guideline value. Application of ≤ 25% pink and violet dye effluent and ≤ 10% black dye effluent had significant (p < 0.05) and positive impacts on growth and yield parameters. Heavy metal content in seedlings increased with increasing effluent application rate and crossed the utmost permissible limit at higher concentration. Survey data discovered a moderate knowledge level among the respondents, which might account for the indiscriminate discharge of loom-dye effluent into the surrounding environment. Attitudes, practices, and protective behaviours of the respondents also reflect the caused for long-term pollution through loom-dye effluents. To reduce its negative effects on the health and crop environment, the loom-dye effluents should not be discharged indiscriminately and used for crop irrigation without proper treatment. Furthermore, training programs ought to be introduced to educate the individuals involved in the discharge and subsequent use of loom-dye effluents.
Show more [+] Less [-]Parasitism, host feeding, and transgenerational effects of three insecticides on the eulophid parasitoid Tamarixia triozae when exposed in the immature stages Full text
2020
Morales, Sinue I. | Martínez, Ana M. | Viñuela, Elisa | Figueroa, José I. | Tamayo, Fernando | Rodríguez-Leyva, Esteban | Pineda, Samuel
The ectoparasitoid Tamarixia triozae is a promising biological control agent of the tomato psyllid, Bactericera cockerelli, based on its high parasitism rates on different crops. The parasitism, host feeding, and transgenerational effects (in terms of sex ratio) of T. triozae females exposed to three insecticides (soybean oil, imidacloprid, and abamectin) as eggs, larvae, and pupae were evaluated when a mixture of second, third, fourth, and fifth instars of the host B. cockerelli was offered. The concentrations bioassayed of each insecticide corresponded to the minimum field-registered concentration [MiFRC] and one-half the MiFRC. No parasitism of B. cockerelli second instars was recorded when parasitoid’s females were exposed in any of the three immature stages to any of the insecticides. In contrast, in some cases, parasitism of T. triozae females treated as eggs, larvae, or pupae with soybean oil and imidacloprid was reduced in third, fourth, or fifth instar. In most cases, the host feeding was reduced in second and third instar of the host B. cockerelli when T. triozae females were treated as eggs, larvae, or pupae. Any insecticide modified the sex ratio in the F2 generation. In conclusion, both parasitism and host feeding were affected by the insecticides depending on the concentration and on the nymphal instar of the host B. cockerelli offered.
Show more [+] Less [-]Cyanobacterial bloom expansion caused by typhoon disturbance in Lake Taihu China Full text
2020
Chen, Huaimin | Zhu, Yuyang | Zhang, Yong | Chen, Xuqing | Wang, Ruochen | Zhu, Wei
It remains unclear why the area of a cyanobacterial bloom increases in a shallow lake after a typhoon passes. In this study, the mechanisms of cyanobacterial bloom expansion were investigated by studying meteorological factors, water quality, algal biomass, and bloom area in Lake Taihu before and after typhoons (2007–2016). Our results showed that typhoon-induced sediment resuspension caused a short-term increase in nutrients, but nutrients returned to pre-typhoon levels after the typhoon passages. The short-term nutrient release during a typhoon did not result in an obvious increase in Microcystis cell density in two bays of Lake Taihu (Gonghu and Meiliang). Under strong winds, Microcystis aggregates were uniformly distributed in the water column downwind and then dispersed into different directions by wind-driven currents. In particular, Microcystis in the surface water were transported to the center of Lake Taihu. After a typhoon, dispersed Microcystis refloated and formed blooms. Thus, the bloom area was enlarged compared with before a typhoon. Several days after a typhoon, the bloom area gradually reduced as a result of a steady breeze on the horizontal accumulation of Microcystis.
Show more [+] Less [-]Facing the threat: common yellowjacket wasps as indicators of heavy metal pollution Full text
2020
Skaldina, Oksana | Ciszek, Robert | Peräniemi, Sirpa | Kolehmainen, Mikko | Sorvari, Jouni
We investigated the common wasp, Vespula vulgaris as a bioindicator and biomonitor of metals in the industrial area. Using traps, we collected 257 yellowjackets along a pollution gradient in the Harjavalta Cu-Ni smelter in Southwest Finland. Our method detected metal elements such as arsenic (As), cobalt (Co), copper (Cu), iron (Fe), nickel (Ni), lead (Pb), zinc (Zn), and mercury (Hg) in wasps. The data analyses revealed V. vulgaris can be a proper indicator for As, Cd, Co, Cu, Ni, and Pb, rather than for Fe and Zn contamination. Body burdens of As, Cd, Co, Cu, Ni, and Pb decreased with an increase in distance from smelter. Enrichment factor (EF) followed the pattern Pb ˃ Cd ˃ As ˃ Co ˃ Cu ˃ Ni. The highest bioaccumulation (BAF) values were revealed for Cd (5.9) and the lowest for Pb (0.1). Specially designed software (WaspFacer) allowed revealing body burdens of As, Cd, Co, Cu, Ni, and Pb to be associated with rather smaller than more asymmetric facial colour markings in yellowjackets. These results add to the body of literature on how heavy metal contaminants can have tangible phenotypic effects on insects and open future opportunities for using wasps as indicators of metal pollution.
Show more [+] Less [-]Properties and characterization of thyme essential oil incorporated collagen hydrolysate films extracted from hide fleshing wastes for active packaging Full text
2020
Ocak, Bugra
In this investigation, collagen hydrolysate (CH) films extracted from hide fleshing wastes were successfully developed using solvent casting method by incorporating different concentrations of thyme essential oil (TO) (2%, 4%, 6%, and 8%) into the CH. Depending on the concentration of TO, thickness, tensile strength (TS), elongation at break (EAB), film solubility (FS), color, opacity, light transmittance, and thermal properties varied. Addition of TO resulted in the increases in the thickness, EAB (%), and light barrier performance of CH–TO films while there was a significant decrease in TS and FS of the CH films (p ≤ 0.05). According to our findings, the increment of TO content induced higher lightness and yellowness but lower redness values compared to CH film. Fourier-transform infrared spectroscopy was conducted to determine the molecular changes and interactions between CH extracted from hide fleshing wastes and TO. In order to analyze the thermal behavior of the films, differential scanning calorimetry analysis was conducted. Moreover, the structure–property relationships of CH and TO were examined by scanning electron microscopy and a reduction in the compact and homogenous structures of the films containing TO was observed. Promising results have been obtained showing that CH-based films can be used for active packaging purposes, thereby contributing to a significant reduction in the environmental impact of both leather solid waste and plastic packaging materials.
Show more [+] Less [-]Impairment of testicular development in rats exposed to acephate during maternal gestation and lactation Full text
2020
Sampaio, Carolina Ferreira | Prates, Kelly Valério | Siervo, Gláucia Eloisa Munhoz Lion | Mathias, Paulo Cézar de Freitas | Fernandes, Glaura Scantamburlo Alves
Acephate is an organophosphate insecticide that disrupts the endocrine system and impairs the male reproductive system. Thus, the aim of the present study was to evaluate whether exposure to acephate during maternal gestation and lactation histologically damages the testes of male Wistar rats in adulthood. For this study, adult Wistar rats were divided into the following groups: ACE-mother, (2.5 mg/kg/bw, gestational day (GD) 7 to postnatal day (PND) 21) and oil-mother (corn oil (control), GD 7 to PND 21). The male offspring (PND 90) were euthanized, and the prostates and testes were collected and weighed. The testes were utilized for histopathological analyses and to determine the sperm count. A spermatogenesis kinetic analysis revealed an increased number of seminiferous tubules in stages I–VI in the ACE-mother group. Additionally, we observed a decrease in the epithelium and the diameters of the evaluated seminiferous tubules and in the number of Sertoli cells in the group exposed to acephate. The sperm count analysis showed no difference between the groups. We conclude that maternal exposure to the pesticide acephate did not affect testicular function, but led to the impairment of testicular development and morphology of the tissue in adulthood.
Show more [+] Less [-]Magnetite-based catalysts for wastewater treatment Full text
2020
Masudi, Ahmad | Harimisa, Grace Erlinda | Ghafar, Nawal Abdul | Jusoh, Nurfatehah Wahyuny Che
The increasing number and concentration of organic pollutants in water stream could become a serious threat in the near future. Magnetite has the potential to degrade pollutants via photocatalysis with a convenient separation process. This study discusses in detail the control size and morphology of magnetite nanoparticles, and their composites with co-precipitation, hydrothermal, sol-gel, and electrochemical route. Further photocatalytic enhancement with the addition of metal and porous support was proposed. This paper also discussed the technology to extend the lifetime of recombination through an in-depth explanation of charge transfer. The possibility to use waste materials as catalyst support was also elucidated. However, magnetite-based photocatalysts still require many improvements to meet commercialization criteria.
Show more [+] Less [-]Electrical energy efficiency of China and its influencing factors Full text
2020
Guang, Fengtao
Due to the implementation of “electrical energy substitution” strategy in China, the proportion of electrical energy in terminal energy consumption is increasing. The improvement of electrical energy efficiency could increase overall energy efficiency. Thus, a special attention should be paid on electrical energy efficiency. An input-oriented epsilon-based measure-DEA (data envelopment analysis) model was used to measure electrical energy efficiency from the perspective of total factor, and the spatial-temporal variability of electrical energy efficiency was investigated. Results draw that the overall electrical energy efficiency is relatively low and shows a downward trend. The eastern region has the best scores of electrical energy efficiency, followed by the central region and then the western region. Furthermore, the main associated determinants were investigated by panel Tobit regression model. It was found that the effect of industrial structure and economic opening degree on electrical energy efficiency is positive on the whole country level, whereas the effect of government intervention and urbanization is negative. From a regional perspective, there are great differences in the effect of each influencing factors. Some corresponding policy recommendations are given.
Show more [+] Less [-]Catalytic reduction of nitrate with Pd-In2O3 Full text
2020
Pizarro, Alejandro Herrero | Torija, Irene | Moreno, Reyes | Arauzo, Jesús | Monsalvo, Victor M.
This work presents a novel catalyst preparation method and the optimization of operation conditions for an effective NO₃⁻ conversion with a high selectivity and stability that guarantee water quality for human consumption. Catalytic reduction of NO₃⁻ and NO₂⁻ was carried out with Pd supported on In₂O₃ under mild operation conditions (25 °C, 1 atm) with H₂ and CO₂ as reducing and acidifying agents, respectively. The catalyst was used in batch experiments showing the suppression of NO₂⁻ accumulation and low NH₄⁺ selectivity at acid pH. Long-term experiments were carried out with Pd on γ-Al₂O₃ spheres covered with In₂O₃. This catalyst presented a high stability during more than 700 h. A concentration of NO₃⁻ below 50 mg/L was achieved, producing less than 0.5 mg/L of NH₄⁺ as reaction by-product by a strict limitation of the H₂ fed and controlling several operating conditions.
Show more [+] Less [-]Diabetes mortality burden attributable to short-term effect of PM10 in China Full text
2020
Yang, Jun | Zhou, Maigeng | Zhang, Fengying | Yin, Peng | Wang, Boguang | Guo, Yuming | Tong, Shilu | Wang, Hao | Zhang, Chunlin | Sun, Qinghua | Song, Xiuping | Liu, Qiyong
Ambient air pollution may be associated with diabetes mellitus. However, evidence from developing countries is limited although the concentrations of air pollution are disproportionably higher in these countries. We collected daily data on diabetes mortality, air pollution, and weather conditions from 16 Chinese provincial cities during 2007–2013. A quasi-Poisson regression combined with a distributed lag model was used to quantify the city-specific mortality risk of PM₁₀ (particulate matter with aerodynamic diameter < 10 μm). Then, a random-effect meta-analysis was conducted to pool effect estimates from 16 cities. We also calculated the attributable fraction and attributable number of diabetes mortality due to PM₁₀. Effects of PM₁₀ were found to be acute and limited to 3 days. Harvesting effect of PM₁₀ was found during lag 4–10 days on diabetes mortality. An increase of 0.17% (95%CI: 0.01–0.34), 0.48% (95%CI: 0.22–0.73), and 0.53% (95%CI: 0.27–0.80) in diabetes mortality was associated with per 10 μg/m³ increase in PM₁₀ at lag 0, 0–4 and 0–10 days, respectively. Totally, 5.76% (95%CI: 2.59–8.00%) and 5878 (95%CI: 2639–8163) deaths due to diabetes could be attributable to PM₁₀. If the concentration of PM₁₀ attained the Chinese government and WHO targets, the reduction in number of PM₂.₅-attributed diabetes deaths was 2016 and 5528, respectively. Higher effect estimates of PM₁₀ were observed among females and those aged 0–64 years old at lag 0 day, while greater cumulative effects of PM₁₀ were among males, the elderly aged 75 or over, and the illiterate at lag 0–10 days. However, the between-group differences were not statistically significant. It is one of the few studies on examining the attributable burden of diabetes mortality caused by particulate matter. Our findings indicated that effective efforts on controlling air pollution could reduce a prominent number of air pollution-related diabetes deaths.
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