Biomonitoring of Polycyclic Aromatic Hydrocarbon Deposition in Greenland Using Historical Moss Herbarium Specimens Shows a Decrease in Pollution During the 20th Century

Review on biochar as a sustainable green resource for the rehabilitation of petroleum hydrocarbon-contaminated soil

Petroleum pollution is one of the primary threats to the environment and public health. Therefore, it is essential to create new strategies and enhance current ones. The process of biological reclamation, which utilizes a biological agent to eliminate harmful substances from polluted soil, has drawn much interest. Biochars are inexpensive, environmentally beneficial carbon compounds extensively employed to remove petroleum hydrocarbons from the environment. Biochar has demonstrated an excellent capability to remediate soil pollutants because of its abundant supply of the required raw materials, sustainability, affordability, high efficacy, substantial specific surface area, and desired physical-chemical surface characteristics. This paper reviews biochar's methods, effectiveness, and possible toxic effects on the natural environment, amended biochar, and their integration with other remediating materials towards sustainable remediation of petroleum-polluted soil environments. Efforts are being undertaken to enhance the effectiveness of biochar in the hydrocarbon-based rehabilitation approach by altering its characteristics. Additionally, the adsorption, biodegradability, chemical breakdown, and regenerative facets of biochar amendment and combined usage culminated in augmenting the remedial effectiveness. Lastly, several shortcomings of the prevailing methods and prospective directions were provided to overcome the constraints in tailored biochar studies for long-term performance stability and ecological sustainability towards restoring petroleum hydrocarbon adultered soil environments.

Investigation of the spatial distribution of airborne polycyclic aromatic hydrocarbons using Rhytidiadelphus squarrosus in Tórshavn, Faroe Islands

Due to adverse effects of Polycyclic Aromatic Hydrocarbons (PAHs) on human health, it is important to understand how airborne PAHs, are spatially distributed within urban areas. Moss has been shown to be a suitable material for biomonitoring of airborne PAH pollution. In this study, the moss Rhytidiadelphus squarrosus was sampled throughout Tórshavn, Faroe Islands. 53 Rhytidiadelphus squarrosus samples were extracted using a matrix solid-phase dispersive extraction method and analysed for 19 parent PAHs and six groups of alkylated PAHs using gas chromatography mass-spectrometry. All PAHs were quantified in at least one Rhytidiadelphus squarrosus sample, and the sum of the EPA 16 PAHs (ƩPAHEPA16) ranged from 0.90 to 344 µg kg-1 dry weight. Higher concentrations were found close to the harbour and the main roads. The spatial correlation was investigated for the ƩPAHEPA16, pyrene, fluoranthene, chrysene, benzo(e)pyrene, benzo(g,h,i)perylene, C1-phenanthrenes/C1-anthracenes, and C2-phenanthrenes/C2-anthracenes using variograms. The effective range of the spatial correlation was between 500 to 700 m of all PAHs. The evaluation of diagnostic ratios of fluoranthene to pyrene, and benzo(a)anthracene to chrysene suggest that different pollution sources affect urban areas of different types. To the best of our knowledge, this is the first time airborne PAH pollution patterns were mapped in an Arctic town, and the first time, Rhytidiadelphus squarrosus was used for tracing PAH pollution sources. Rhytidiadelphus squarrosus is suitable for biomonitoring and mapping PAH pollution within urban areas since it is widespread, and suitable for mapping PAHs.

Polycyclic aromatic hydrocarbons (PAHs) levels in PM10 and bulk deposition using Mosspheres: A pilot study in an urban environment

Study air polycyclic aromatic hydrocarbons (PAHs) capturing the spatial variability of their concentrations is not economically feasible with conventional methods. In the present work we tested, for the first time and under real conditions, the suitability for intensive monitoring and mapping these contaminants of innovative, cost-effective passive air samplers known as "Mosspheres". The Mosspheres, filled with a devitalised Sphagnum palustre L. moss clone, were placed in a 575 m. grid in a medium-sized European city for three months. Concentrations in the moss tissues of 15 priority PAHs, including benzo(a)pyrene, were determined and converted into PM₁₀ and bulk deposition with the equations proposed in a recent study. Low concentrations of PAHs were detected, with only a few enriched points never exceeding the legal thresholds, near industrial areas and busy roads. Despite these low PAH concentrations, Mosspheres were able to detect spatial structure for several PAHs and high-resolution pollution maps were constructed for these compounds. The results prove the high sensitivity and suitability of Mosspheres for mapping PAH levels and for quantitative (i.e. PAHs with 4 or more rings) and qualitative (3-ring PAHs) monitoring. Thus, this study supports their widespread application and its potential inclusion in European Directives on air quality control.

Global ambient air quality monitoring: Can mosses help? A systematic meta-analysis of literature about passive moss biomonitoring

Surging incidents of air quality-related public health hazards, and environmental degradation, have prompted the global authorities to seek newer avenues of air quality monitoring, especially in developing economies, where the situation appears most alarming besides difficulties around 'adequate' deployment of air quality sensors. In the present narrative, we adopt a systematic review methodology (PRISMA, Preferred Reporting Items for Systematic reviews and Meta-Analyses) around recent global literature (2002-2022), around moss-based passive biomonitoring approaches which might offer the regulatory authorities a complementary means to fill 'gaps' in existing air quality records. Following the 4-phased search procedure under PRISMA, total of 123 documents were selected for review. A wealth of research demonstrates how passive biomonitoring, with strategic use of mosses, could become an invaluable regulatory (and research) tool to monitor atmospheric deposition patterns and help identifying the main drivers of air quality changes (e.g., anthropogenic and/or natural). Besides individual studies, we briefly reflect on the European Moss Survey, underway since 1990, which aptly showcases mosses as 'naturally occurring' sensors of ambient air quality for a slew of metals (heavy and trace) and persistent organic pollutants, and help assessing spatio-temporal changes therein. To that end, we urge the global research community to conduct targeted research around various pollutant uptake mechanisms by mosses (e.g., species-specific interactions, environmental conditions, land management practices). Of late, mosses have found various environmental applications as well, such as in epidemiological investigations, identification of pollutant sources and transport mechanisms, assessment of air quality in diverse and complex urban ecosystems, and even detecting short-term changes in ambient air quality (e.g., COVID-19 Lockdown), each being critical for the authorities to develop informed and strategic regulatory measures. To that end, we review current literature and highlight to the regulatory authorities how to extend moss-based observations, by integrating them with a wide range of ecological indicators to assess regional environmental vulnerability/risk due to degrading air quality. Overall, an underlying motive behind this narrative was to broaden the current regulatory outlook and purview, to bolster and diversify existing air quality monitoring initiatives, by coupling the moss-based outputs with the traditional, sensor-based datasets, and attain improved spatial representation. However, we also make a strong case of conducting more targeted research to fill in the 'gaps' in our current understanding of moss-based passive biomonitoring details, with increased case studies.

Supplementary Information

The online version contains supplementary material available at 10.1007/s10668-023-03043-0.

The Application of Active Biomonitoring with the Use of Mosses to Identify Polycyclic Aromatic Hydrocarbons in an Atmospheric Aerosol

The use of biological indicators of environmental quality is an alternative method of monitoring ecosystem pollution. Various groups of contaminants, including organic ones, can be measured in environmental samples. Polycyclic aromatic hydrocarbons (PAHs) have not yet been determined by the moss bag technique. This technique uses several moss species simultaneously in urban areas to select the best biomonitoring of these compounds, which are dangerous to humans and the environment. In this research, a gas chromatography coupled with mass spectrometry was used for the determination of selected PAHs in three species of mosses: Pleurozium schreberi, Sphagnum fallax and Dicranum polysetum (active biomonitoring) and for comparison using an air filter reference method for atmospheric aerosol monitoring. The chlorophyll fluorescence of photosystem II (PSII) was also measured to assess changes in moss viability during the study. As a result of the study, the selective accumulation of selected PAHs by mosses was found, with Pleurozium schreberi being the best bioindicator—9 out of 13 PAHs compounds were determined in this species. The photosynthetic yield of photosystem (II) decreased by 81% during the exposure time. The relationship between PAHs concentrations in mosses and the total suspended particles (TSP) on the filter indicated the possibility of using this bioindicator to trace PAHs in urban areas and to apply the moss bag technique as a method supporting classical instrumental air monitoring.

PAHs in an urban-industrial area: The role of lichen transplants in the detection of local and study area scale patterns

Spatial variation of the levels of polycyclic aromatic hydrocarbons (PAHs) was evaluated within an urban-industrial district where the main anthropogenic pressures are a 15 MW biomass power plant (BPP) and road traffic. The use of a high-density lichen transplant network and wind quantitative relationships made it possible to perform a hierarchical analysis of contamination. Combined uni-bi and multivariate statistical analyses of the resulting databases revealed a dual pattern. In its surroundings (local scale), the BPP affected the bioaccumulation of fluoranthene, pyrene and total PAHs, although a confounding effect of traffic (mostly petrol/gasoline engines) was evident. Spatial variation of the rate of diesel vehicles showed a significant association with that of acenaphthylene, acenaphthene, fluorene, anthracene and naphthalene. The series of high-speed wind values suggests that wind promotes diffusion rather than dispersion of the monitored PAHs. At the whole study area scale, the BPP was a source of acenaphthylene and acenaphthene, while diesel vehicles were a source of acenaphthylene. PAHs contamination strongly promotes oxidative stress (a threefold increase vs pre-exposure levels) in lichen transplants, suggesting a marked polluting effect of anthropogenic sources especially at the expense of the mycobiont. The proposed monitoring approach could improve the apportionment of the different contributions of point and linear anthropogenic sources of PAHs, mitigating the reciprocal biases affecting their spatial patterns.

Pollutants from shipping - new environmental challenges in the subarctic and the Arctic Ocean

Maritime activities in the subarctic and Arctic Ocean are predicted to substantially increase in the future due to climate change and declining sea ice cover. Inevitably, the consequences will be seen in impacts on marine ecosystems in this region at many different levels, such as increased pollution load due to antifouling biocides, polycyclic aromatic hydrocarbons, metals and pharmaceuticals. Here we discuss the current situation and evaluate the effect of increased shipping on the environmental status of subarctic and Arctic waters, in relation to elevated loads of both legacy and emerging pollutants in the region. It is of high importance to evaluate the current levels of selected pollutants, which will most likely rise in near future. Furthermore, it is important to improve our understanding of the effects of these pollutants on marine organisms at high latitudes, as the pollutants may behave differently in cold environments compared to organisms at lower latitudes, due to dissimilar physiological responses and adaptations of the cold-water organisms. Integrative studies are needed to better understand the impact of pollutants on the marine fauna while monitoring programmes and research should be continued, with an increased capacity for emerging pollutants of concern.