Volatile organic compounds (VOCs) are of public concern due to their adverse health effects. Botanical air filtration is a promising technology for reducing indoor air contaminants, but the underlying mechanisms are not fully understood. This study assessed active botanical biofilters for their single-pass removal efficiency (SPRE) for benzene, ethyl acetate and ambient total volatile organic compounds (TVOCs), at concentrations of in situ relevance. Biofilters containing four plant species (Chlorophytum orchidastrum, Nematanthus glabra, Nephrolepis cordifolia ‘duffii’ and Schefflera arboricola) were compared to discern whether plant selection influenced VOC SPRE. Amongst all tested plant species, benzene SPREs were between 45.54 and 59.50%, with N. glabra the most efficient. The botanical biofilters removed 32.36–91.19% of ethyl acetate, with C. orchidastrum and S. arboricola recording significantly higher ethyl acetate SPREs than N. glabra and N. cordifolia. These findings thus indicate that plant type influences botanical biofilter VOC removal. It is proposed that ethyl acetate SPREs were dependent on hydrophilic adsorbent sites, with increasing root surface area, root diameter and root mass all associated with increasing ethyl acetate SPRE. The high benzene SPRE of N. glabra is likely due to the high wax content in its leaf cuticles. The SPREs for the relatively low levels of ambient TVOCs were consistent amongst plant species, providing no evidence to suggest that in situ TVOC removal is influenced by plant choice. Nonetheless, as inter-species differences do exist for some VOCs, botanical biofilters using a mixture of plants is proposed.

Coupled bioelectrochemical system-upflow anaerobic sludge blanket (BES-UASB) was utilized for wastewater treatment containing 2,4-dichloronitrobenzene (DClNB). The results indicated that a proper voltage enhanced the DClNB reduction, however, over high voltage presented a negative impact (2.0 V). Synergistic effect of external voltage and anaerobic sludge was observed, and dechlorination efficiency reached 57.8 ± 5.4% in the coupled BES, which was higher than the sum of anaerobic sludge and electric system (48.2%). Moreover, the coupled system was more tolerant of high salinity and pollutant concentration. Dehydrogenase activity (DHA) was related to microbial electron transfer activity and DHA reached a maximum 453 ± 33 μgTF g⁻¹VSS h⁻¹ in the coupled reactor which was 1.6-fold that of the control, meanwhile, extracellular polymeric substances (EPS) content was significantly enhanced in the presence of external voltage. In summary, the coupled BES-UASB systems could be an alternative for removal of recalcitrant pollutants such as DClNB.

The concentration level related to toxicities of trace elements in drinking water, rice, wheat flour, and their associated negative impacts on human health have become an emergent issue in China. Because Xinjiang is the largest province in China with the majority of arable pasture land available for cultivation, it is important to analyze the concentrations of trace elements in relation to their toxicities in water, rice, and wheat flour and to investigate the health risk differences between agricultural and pastoral areas in Bay County, Xinjiang. The study results showed that (1) metal concentrations from drinking water, rice, and wheat flour were within the permissible limits; (2) concentration levels of trace elements and their total risk from drinking water and rice were higher in the agricultural areas than those in the pastoral areas, whereas concentration levels of trace elements and their total risk from wheat flour were higher in the pastoral areas than those in the agricultural areas; (3) the concentration level of the trace elements in rice were higher than in the wheat flour, but the risk from the wheat flour was higher than the risk from rice; (4) total non-cancer risk from the flour (HIf) in both areas exceeded the respective safe reference doses; (5) total cancer risk from the wheat flour, rice, and water exceeded the safety limit (1 × 10⁻⁴); (6) for the exposed population, arsenic was suggested as the most evident pollutant leading to carcinogenic concerns regarding the water, rice, and wheat flour; (7) the risk index from the wheat flour made up the highest percentage both in the total cancer risk and the non-cancer risk, followed by rice and then water; and (8) the human health risk was attributed to influence from the local environment in the agriculture areas, while it was attributed to the external environment in the pastoral areas. Graphical abstract

Groundwater is a major resource for water supply in Canada, and 43 of 68 Saskatchewan municipalities rely on groundwater or combined groundwater and surface water sources. The Regina landfill is built on top of the Condie aquifer, without an engineered liner. Missing data and inconsistent sampling make a traditional groundwater assessment difficult. An integrated statistical approach using principle component analysis, correlation analysis, ion plots, and multiple linear regression is used to study groundwater contamination at the Regina landfill. Geological locations of the water samples were explicitly considered. The abundance of cations in the groundwater was Ca²⁺ > Mg²⁺ > Na⁺ > K⁺ > Mn²⁺; and for anions SO₄²⁻ > HCO₃⁻ > Cl⁻. Correlation analysis and ion plots pointed to gypsum and halite dissolution being the main factors affecting groundwater chemistry. Principal component analysis yielded three principal components, responsible for 80.7% of the total variance. For all monitoring well groups, the sodium absorption ratio was generally less than one. The variation in the ratio from monitoring well groups suggests possible groundwater contamination from landfill operation. Wilcox diagrams indicate groundwater near the landfill is unsuitable for irrigation. A two-step multiple linear regression was used to develop a model for total hardness prediction.

Mercury is a global neurotoxic pollutant, which can be globally transported and bioaccumulated in the food chain. Iron–steel production is one of the most significant sources of anthropogenic atmospheric mercury emission, while information on this source is scarce. Hourly gaseous elemental mercury (GEM) and particle bound mercury (PBM) were studied inside (IP) and at the boundary (BP) of a typical iron–steel plant in the Yangtze River Delta (YRD), China from September 2016 to August 2017. The GEM concentrations were 0.97–503.1 and 0.05–112.6 ng/m³ at the IP and BP sites, respectively, while PBM concentrations were one to four orders of magnitude higher than urban and suburban ambient levels. Several lines of evidences indicated that PBM was mainly originated from the iron–steel manufacturing process, especially from sintering and coke-making processes in this iron–steel plant. However, a combined emission effect contributed to GEM variation. The receptor model of positive matrix factorization (PMF) showed that local direct emissions (coal combustion, industrial activity, vehicle exhaust, and secondary evaporation from polluted soil) contributed 51.3% of the total GEM concentration variation. Potential source contribution function (PSCF) and concentration weighted trajectory (CWT) models clearly showed that air masses moving from areas surrounding YRD had the highest concentrations of atmospheric mercury. These results provided evidence that iron–steel manufacturing emissions have a considerable effect on regional atmospheric mercury concentrations, especially PBM.

The attractive qualities of plastics lead us, around the world, to an enormous need for plastic goods, which results in their unsustainable overconsumption. Bio-based products are the core concept of circular economy, yet this sector suffers from the high cost of their production. In practice, biopolymers, such as polylactic acid (PLA), are still limitedly used, due to their expensiveness and not outstanding technological properties. A circular and sustainable solution would be to use waste from the food industry as filler that contributes to reduce the cost of PLA-based materials, thereby encouraging their widespread use. At the same time, this would be a circular approach to wisely upgrade food waste and prevent pollution. Ceramic food waste powder fillers from egg shells and from mussel shells were compounded with PLA at 180 °C to obtain composites, which contain an unprecedented high amount of filler, equal to 140 over 100 parts of PLA. We analyzed volatile organic compounds emitted from PLA and, for the very first time, from its composites via headspace-solid phase microextraction-gas chromatography-mass spectrometry (HS-SPME-GC-MS). The molecular fingerprint of the volatiles comprises only three aldehydes, a ketone, and two lactides. Volatiles typical of fossil plastics, that are causative factors of hormone disruption or reproductive dysfunction, are effectively missing. Scanning electron microscopy, used to examine the structure of the composite, indicates that both the egg shells and the mussel shells are suitable fillers, in that they form a sufficiently strong interface with the polymer.

Wastewater treatment plants (WWTPs) have been identified as “hot spots” of antibiotics release to the environment. Treatment operations at WWTPs may remove a significant proportion of antibiotics from influent wastewater; however, the effects of tertiary treatment processes on antibiotics removal are not well understood. The objective of this review is to summarize the current literature regarding antibiotics removal from common tertiary processes at full-scale municipal WWTPs and to reveal the research gaps and inform future research directions. Chlorination, ultraviolet (UV) irradiation, and sand filtration were reviewed due to their popularity of application in the USA. The majority of studies of antibiotics removal via tertiary wastewater treatment have been conducted in EU nations, the USA, Australia, and China. Chlorination significantly reduces antibiotics concentrations in wastewater effluents. In comparison, sand filtration and UV irradiation are less effective. However, a large discrepancy of removal efficiencies is apparent across different studies of these treatment processes. Increases in antibiotics concentration following tertiary treatment have also been observed. Possible reasons for the discrepancies, such as sorption to filtered particles, sampling strategies, specific operating parameters of wastewater treatment plants, and deconjugation, are discussed. It is concluded that the effects of tertiary treatment on antibiotic removal efficiency are still arguable, and caution must be taken when sampling wastewater in full-scale WWTPs for comparison of removal efficiencies of antibiotics.

The statistics from Europe and the USA have proven a high risk for skin diseases associated with plant contact. Therefore, plant-induced dermatitis is of increasing attention in dermatology. The focus of this paper was to present the current knowledge on aspects of contact allergy related to Asteraceae (Compositae) species. The Asteraceae family is one of the largest in the world with members across all continents. The PubMed/Medline databases have been searched. The Asteraceae representatives consist of diverse secondary metabolites, which exhibit various advantageous effects in humans. In particular, sesquiterpene lactones (SLs) may cause sensitization resulting in skin irritation and inflammation. In this study, we tried to reveal the allergenic potential of several Asteraceae species. The Asteraceae-related allergy symptoms involve eczema, hay fever, asthma, or even anaphylaxis. Furthermore, the evidence of severe cross-reactivity with food and pollen allergens (PFS) in patients sensitive to Asteraceae allergens have been announced. Further identification and characterization of secondary metabolites and possible allergens in Asteraceae are necessary for the better understanding of Asteraceae-related immune response. The Asteraceae allergy screening panel (the SL mix and the Compositae mix of five plant species) is a promising tool to improve allergy diagnostics and therapy.

DDT transformation to DDD in soil is the most commonly reported pathway under anaerobic conditions. A few instances of DDT conversion to products other than DDD/DDE have been reported under aerobic conditions and hardly any under anaerobic conditions. In particular, few reports exist on the anaerobic degradation of DDT in African tropical soils, despite DDT contamination arising from obsolete pesticide stockpiles in the continent as well as new contamination from DDT use for mosquito and tsetse fly control. Moreover, the development of possible remediation strategies for contaminated sites demands adequate understanding of different soil processes and their effect on DDT persistence, hence necessitating the study. The aim of this work was to study the effect of simulated anaerobic conditions and slow-release carbon sources (compost) on the dissipation of DDT in two tropical clay soils (paddy soil and field soil) amenable to periodic flooding. The results showed faster DDT dissipation in the field soil but higher metabolite formation in the paddy soil. To explain this paradox, the levels of dissolved organic carbon and carbon mineralization (CH₄ and CO₂) were correlated with p,p-DDT and p,p-DDD concentrations. It was concluded that DDT underwent reductive degradation (DDD pathway) in the paddy soil and both reductive (DDD pathway) and oxidative degradation (non-DDD pathway) in the field soil.

The maximisation of the efficiency of the photovoltaic system is crucial in order to increase the competitiveness of this technology. Unfortunately, several environmental factors in addition to many alterable and unalterable factors can significantly influence the performance of the PV system. Some of the environmental factors that depend on the site have to do with dust, soiling and pollutants. In this study conducted in the city centre of Kraków, Poland, characterised by high pollution and low wind speed, the focus is on the evaluation of the degradation of efficiency of polycrystalline photovoltaic modules due to natural dust deposition. The experimental results that were obtained demonstrated that deposited dust-related efficiency loss gradually increased with the mass and that it follows the exponential. The maximum dust deposition density observed for rainless exposure periods of 1 week exceeds 300 mg/m² and the results in efficiency loss were about 2.1%. It was observed that efficiency loss is not only mass-dependent but that it also depends on the dust properties. The small positive effect of the tiny dust layer which slightly increases in surface roughness on the module performance was also observed. The results that were obtained enable the development of a reliable model for the degradation of the efficiency of the PV module caused by dust deposition. The novelty consists in the model, which is easy to apply and which is dependent on the dust mass, for low and moderate naturally deposited dust concentration (up to 1 and 5 g/m² and representative for many geographical regions) and which is applicable to the majority of cases met in an urban and non-urban polluted area can be used to evaluate the dust deposition-related derating factor (efficiency loss), which is very much sought after by the system designers, and tools used for computer modelling and system malfunction detection.