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Tissue distribution of phthalates in celery under different cultivation patterns and associated dietary exposure Full text
2022
Zhao, Fang | Ma, Zhihong | Ping, Hua | He, Zhaoying | Li, Bingru | Gao, Yuan | Li, Cheng
To investigate tissue distribution, spatial difference, temperature variation, and potential health risks of PAEs in vegetables, celery was used as a model plant. Celery samples were collected from open fields and greenhouses from two provinces in China over four seasons. Celery tissues were analyzed for 16 PAE compounds by gas chromatography–tandem mass spectrometry. The total content of PAEs was 89.0–1130.3 μg kg⁻¹ dry weight (dw) in stems and 155.0–2730.8 μg kg⁻¹ dw in leaves. Concentrations of PAEs in celeries showed notable spatial differences (P < 0.05), and the levels in samples from open fields were lower than those in samples from plastic greenhouses. In celeries from greenhouses, higher PAE concentrations were observed for plants grown at high temperatures than in plants grown at low temperatures. Discrepancies in tissue distribution indicated different uptake pathways of PAE contaminants. Risk assessments to humans found that both carcinogenic risks and non-carcinogenic risks of PAEs via celery consumption were at an acceptable level. Further research should consider other exposure pathways of PAEs and pay special attention to reducing PAE contents in vegetables.
Show more [+] Less [-]Sediment nitrogen contents controlled by microbial community in a eutrophic tributary in Three Gorges Reservoir Full text
2022
Lv, Kun | Guo, Xiaojuan | Wang, Congfeng | Su, Qingqing | Liu, Defu | Xiao, Shangbin | Yang, Zhengjian
Nitrogen pollution caused serious environmental problems in reservoir ecosystems. Reducing nitrogen pollution by enhancing nitrogen removal in river sediments deserved intensive research. Distributions of nitrogen contents in sediment-water interface were characterized along the Xiangxi bay (XXB), a eutrophic tributary in Three Gorges Reservoir, China. More than 47% of total Kjeldahl nitrogen (TKN) and 67% of total organic nitrogen (TON) were degraded during burial. Higher TN, TON and NH₄⁺ consuming at downstream sites indicated stronger nitrogen mineralization and release due to higher turbulence of the overlying density currents. Nitrifying bacteria, denitrifying bacteria, anaerobic ammonium oxidizing (anammox) bacteria and nitrite/nitrate-dependent anaerobic methane oxidation (N-DAMO) bacteria were detected in nitrate-ammonium transition zone. Nitrogen contents transitions were responded to microbial stakeholders indicated microbially mediated nitrogen cycling in sediments. The dissolved oxygen and nitrate availabilities were the key limits of denitrification and associated reactions. These results suggested microbial mediated nitrogen cycling processes in sediments were critical for nitrogen removal in aquatic ecosystems, and replenishing dissolved oxygen and nitrate was expected to enhance sediment denitrification and strengthen potential environmental self-purification.
Show more [+] Less [-]Photolytic degradation of novel polymeric and monomeric brominated flame retardants: Investigation of endocrine disruption, physiological and ecotoxicological effects Full text
2022
Esther, Smollich | Malte, Büter | Gerhard, Schertzinger | Elke, Dopp | Bernd, Sures
Ecotoxicological effects of photolytic degradation mixtures of the two brominated flame retardants PolymericFR and Tetrabromobisphenol A-bis (2,3-dibrom-2-methyl-propyl) Ether (TBBPA-BDBMPE) have been studied in vitro and in vivo. Both substances were experimentally degraded separately by exposure to artificial UV-light and the resulting degradation mixtures from different time points during the UV-exposure were applied in ecotoxicological tests. The in vitro investigation showed no effects of the degraded flame retardants on the estrogenic and androgenic receptors via the CALUX (chemically activated luciferase gene expression) assay. Short-term exposures (up to 96 h) of Lumbriculus variegatus lead to temporary physiological reactions of the annelid. The exposure to degraded PolymericFR lead to an increased activity of Catalase, while the degradation mixture of TBBPA-BDBMPE caused increases of Glutathione-S-transferase and Acetylcholine esterase activities. Following a chronic exposure (28 d) of L. variegatus, no effects on the growth, reproduction, fragmentation and energy storage of the annelid were detected. The results indicate that the experimental degradation of the two flame retardants causes changes in their ecotoxicological potential. This might lead to acute physiological effects on aquatic annelids, which, however, do not affect the animals chronically according to our results.
Show more [+] Less [-]Current progress in treatment technologies for plastic waste (bisphenol A) in aquatic environment: Occurrence, toxicity and remediation mechanisms Full text
2022
Kataria, Navish | Bhushan, Divya | Gupta, Renuka | Rajendran, Saravanan | Mun Teo, Michelle Yee | Khoo, Kuan Shiong
Bisphenol-A (BPA) is a type of Endocrine Disrupting Compound (EDC) that is being widely used in the production of polycarbonate and epoxy resins. Last few years, the human exposure to BPA has been extensively high due to continuous increment in Annual Growth Rate (AGR) of BPA global market. The presence and transportation of BPA in the environment could cause serious damage to the aquatic life and human health. In this paper, we have reviewed the literature on the exposure and toxicity mechanism of BPA and advanced analytical techniques for detection of BPA in environment and human beings. The study indicated that BPA can cause damaging effects on numerous tissues and organs, including reproductive system, metabolic dysfunction, respiratory system, immune system and central nervous system. On the basis of reported studies on animal indicates that the exposure of BPA can be the carcinogenic and responsible for causing a variety of cancers like ovarian cancer, uterine cancer, prostate cancer, testicular cancer and liver cancer. This review paper mainly focused on current progress in BPA removal technologies in last ten years (2012–2022). This paper presenting the comprehensive overview of individual removal technology including-adsorption, photocatalysis/photodegradation, ozonation/advance oxidation, photo-fenton, membrane/nanofilters, and biodegradation along with removal mechanism. The extensive literature study shows that each technology has its own removal mechanism and limitation in BPA treatment. In adsorption and membrane separation process, most of BPA has been treated by electrostatic interaction, hydrogen boning and π-π interations mechanism. Whereas in degradation mechanism, O* and OH* species has been played major role in BPA removal. Some factors could be altered the removal potential and efficiency of BPA removal. This review paper will provide a useful guide in providing directions for future investigation to address the problem of BPA-containing wastewater treatment.
Show more [+] Less [-]Xenobiotic pollution affects transcription of antibiotic resistance and virulence factors in aquatic microcosms Full text
2022
Zhang, Zhenyan | Wang, Yan | Chen, Bingfeng | Lei, Chaotang | Yu, Yitian | Xu, Nuohan | Zhang, Qi | Wang, Tingzhang | Gao, Wenwen | Lu, Tao | Gillings, Michael | Qian, Haifeng
Antibiotic resistance genes (ARGs) and virulence factors (VFs) are critical threats to human health. Their abundance in aquatic ecosystems is maintained and enhanced via selection driven by environmental xenobiotics. However, their activity and expression in these environments under xenobiotic stress remains unknown. Here ARG and VF expression profiles were examined in aquatic microcosms under ciprofloxacin, glyphosate and sertraline hydrochloride treatment. Ciprofloxacin increased total expression of ARGs, particularly multidrug resistance genes. Total expression of ARGs and VFs decreased significantly under glyphosate and sertraline treatments. However, in opportunistic human pathogens, these agents increased expression of both ARGs and VFs. Xenobiotic pollutants, such as the compounds we tested here, have the potential to disrupt microbial ecology, promote resistance, and increase risk to human health. This study systematically evaluated the effects of environmental xenobiotics on transcription of ARGs and VFs, both of which have direct relevance to human health. Transcription of such genes has been overlooked in previous studies.
Show more [+] Less [-]Generation of novel n-p-n (CeO2-PPy-ZnO) heterojunction for photocatalytic degradation of micro-organic pollutants Full text
2022
Rajendran, Saravanan | Hoang, Tuan K.A. | Trudeau, Michel L. | Jalil, A.A. | Naushad, Mu | Awual, Md Rabiul
Recently, hetero junction materials (p-n-p and n-p-n) have been developed for uplifting the visible light activity to destroy the harmful pollutants in wastewater. This manuscript presents a vivid description of novel n-p-n junction materials namely CeO₂-PPy-ZnO. This novel n-p-n junction was applied as the photocatalyst in drifting the mobility of charge carriers and hence obtaining the better photocatalytic activity when compared with p-n and pure system. Such catalyst's syntheses were successful via the copolymerization method. The structural, morphological and optical characterization techniques were applied to identify the physio-chemical properties of the prepared materials. Additionally, the superior performance of this n-p-n nanostructured material was demonstrated in the destruction of micro organic (chlorophenol) toxic wastes under visible light. The accomplished ability of the prepared catalysts (up to 92% degradation of chlorophenol after 180 min of irradiation) and their profound degradation mechanism was explained in detail.
Show more [+] Less [-]Evaluating the effects of aquaculture on the freshwater lake from the perspective of plankton communities: The diversity, co-occurrence patterns and their underlying mechanisms Full text
2022
Xu, Huimin | Zhao, Dayong | Zeng, Jin | Mao, Zhigang | Gu, Xiaohong | Wu, Qinglong L.
Aquaculture has significant impacts on freshwater lakes, but plankton communities, as key components of the microbial food web, are rarely considered when assessing the impacts of aquaculture. Revealing the dynamics of plankton communities, including bacterioplankton, phytoplankton and zooplankton, under anthropological disturbances is critical for predicting the freshwater ecosystem functioning in response to future environmental changes. In the present study, we examined the impacts of aquaculture on water quality, plankton diversity and the co-occurrence patterns within plankton metacommunities in a shallow freshwater lake. The study zones are influenced by the 20-year historical intensive aquaculture, but now they are undergoing either ecological aquaculture or ecological restoration. Our results showed that ecological aquaculture was more efficient in nitrogen removal than ecological restoration. Moreover, lower bacterioplankton diversity but higher phytoplankton and zooplankton diversity were found in the ecological aquaculture and ecological restoration zones compared to the control zone. The lower network connectivity of the plankton metacommunities in the ecological aquaculture and ecological restoration zones indicated the decreasing complexity of potential microbial food web, suggesting a possible lower resistance of the plankton metacommunities to future disturbance. Furthermore, plankton communities of different trophic levels were driven under distinct mechanisms. The bacterioplankton community was primarily affected by abiotic factors, whereas the phytoplankton and zooplankton communities were explained more by trophic interactions. These results revealed the impacts of aquaculture on the plankton communities and their potential interactions, thereby providing fundamental information for better understanding the impacts of aquaculture on freshwater ecosystem functioning.
Show more [+] Less [-]Interrelationships among feather mercury content, body condition and feather corticosterone in a Neotropical migratory bird, the Purple Martin (Progne subis subis) Full text
2022
Branco, Jonathan M. | Hingst-Zaher, Erika | Jordan-Ward, Renee | Dillon, Danielle | Siegrist, Joe | Fischer, Jason D. | Schiesari, Luis | von Hippel, Frank A. | Buck, C Loren
Purple Martins (Progne subis) are migratory birds that breed in North America and overwinter and complete their molt in South America. Many of the breeding populations are declining. The eastern North American subspecies of Purple Martin (P. subis subis) comprises >90% of all Purple Martins. This subspecies overwinters and molts in the Amazon Basin, a region that is high in mercury (Hg) contamination, which raises the possibility that observed declines in Purple Martins could be linked to Hg exposure. Exposure to Hg results in numerous and systemic negative health outcomes, including endocrine disruption. Corticosterone (CORT) is a primary modulator of the stress and metabolic axes of vertebrates; thus, it is important in meeting metabolic and other challenges of migration. Because feathers accumulate Hg and hormones while growing, quantification of Hg and CORT in feathers provides an opportunity to retrospectively assess Hg exposure and adrenal activity of birds using minimally invasive methods. We evaluated interrelationships among concentrations of total Hg (THg) and CORT in feathers that grew in the Amazon Basin and body condition (mass, fat score) of these birds in North America. Concentrations of THg in Purple Martin feathers ranged from 1.103 to 8.740 μg/g dw, levels associated with negative physiological impacts in other avian species. Concentrations of CORT did not correlate with THg concentration at the time of feather growth. However, we found evidence that THg concentration may negatively impact the ability of Purple Martins to accumulate fat, which could impair migratory performance and survivorship due to the high energy requirements of migration. This finding suggests potential carryover effects of Hg contamination at the wintering grounds in the Amazon to the summer breeding grounds in North America.
Show more [+] Less [-]Associations of parks, greenness, and blue space with cardiovascular and respiratory disease hospitalization in the US Medicare cohort Full text
2022
Klompmaker, Jochem O. | Laden, Francine | Browning, Matthew H.E.M. | Dominici, Francesca | Ogletree, S Scott | Rigolon, Alessandro | Hart, Jaime E. | James, Peter
Natural environments have been linked to decreased risk of cardiovascular disease (CVD) and respiratory disease (RSD) mortality. However, few cohort studies have looked at associations of natural environments with CVD or RSD hospitalization. The aim of this study was to evaluate these associations in a cohort of U.S. Medicare beneficiaries (∼63 million individuals). Our open cohort included all fee-for-service Medicare beneficiaries (2000–2016), aged ≥65, living in the contiguous U.S. We assessed zip code-level park cover based on the United States Geological Survey Protected Areas Database, average greenness (Normalized Difference Vegetation Index, NDVI), and percent blue space cover based on Landsat satellite images. Cox-equivalent Poisson models were used to estimate associations of the exposures with first CVD and RSD hospitalization in the full cohort and among those living in urban zip codes (≥1000 persons/mile²). NDVI was weakly negatively correlated with percent park cover (Spearman ρ = −0.23) and not correlated with percent blue space (Spearman ρ = 0.00). After adjustment for potential confounders, percent park cover was not associated with CVD or RSD hospitalization in the full or urban population. An IQR (0.27) increase in NDVI was negatively associated with CVD (HR: 0.97, 95%CI: 0.96, 0.97), but not with RSD hospitalization (HR: 0.99, 95%CI: 0.98, 1.00). In urban zip codes, an IQR increase in NDVI was positively associated with RSD hospitalization (HR: 1.02, 95%CI: 1.00, 1.03). In stratified analyses, percent park cover was negatively associated with CVD and RSD hospitalization for Medicaid eligible individuals and individuals living in low socioeconomic status neighborhoods in the urban population. We observed no associations of percent blue space cover with CVD or RSD hospitalization. This study suggests that natural environments may benefit cardiorespiratory health; however, benefits may be limited to certain contexts and certain health outcomes.
Show more [+] Less [-]Association of ambient air pollution exposure and its variability with subjective sleep quality in China: A multilevel modeling analysis Full text
2022
Wang, Lingli | Zhang, Jingxuan | Wei, Jing | Zong, Jingru | Lü, Chunyu | Du, Yajie | Wang, Qing
Growing epidemiological evidence has shown that exposure to ambient air pollution contributes to poor sleep quality. However, whether variability in air pollution exposure affects sleep quality remains unclear. Based on a large sample in China, this study linked individual air pollutant exposure levels and temporal variability with subjective sleep quality. Town-level data on daily air pollution concentration for 30 days prior to the survey date were collected, and the monthly mean value, standard deviations, number of heavily polluted days, and trajectory for six common pollutants were calculated to measure air pollution exposure and its variations. Sleep quality was subjectively assessed using the Pittsburgh Sleep Quality Index (PSQI), and a PSQI score above 5 indicated overall poor sleep quality. Multilevel and negative control models were used. Both air pollution exposure and variability contributed to poor sleep quality. A one-point increase in the one-month mean concentration of particulate matter with aerodynamic diameters of ≤2.5 μm (PM₂.₅) and ≤10 μm (PM₁₀) led to 0.4% (95% confidence interval (CI): 1.002–1.006) and 0.3% (95% CI: 1.001–1.004) increases in the likelihoods of overall poor sleep quality (PSQI score >5), respectively; the odds ratios of a heavy pollution day with PM₂.₅ and PM₁₀ were 2.2% (95% CI: 1.012–1.032) and 2.2% (95% CI: 1.012–1.032), respectively. Although the mean concentrations of nitrogen dioxide, sulfur dioxide, and carbon monoxide met the national standard, they contributed to the likelihood of overall poor sleep quality (PSQI score >5). A trajectory of air pollution exposure with maximum variability was associated with a higher likelihood of overall poor sleep quality (PSQI score >5). Subjective measures of sleep latency, duration, and efficiency (derived from PSQI) were affected in most cases. Thus, sleep health improvements should account for air pollution exposure and its variations in China under relatively high air pollution levels.
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