In recent years, the widespread use of rare earth elements (REEs) has raised the issue of their harmful effects on the aquatic environment. REEs are now considered as contaminants of emerging concern. Despite the increasing interest of REEs in modern industry, there is still a lack of knowledge on their potential impact on the environment and especially in the marine environment. In this context, the need for monitoring tools to assess REEs pollution status in marine ecosystems is considered as the first step towards their risk assessment. Similar to mussels, filter-feeder sponges have emerged as a key bio-monitor species for marine chemical pollution. Their key position at a low level of the trophic chain makes them suitable model organisms for the study of REEs potential transfer through the aquatic food web. We therefore undertook a comparative study on seven marine sponge species, assessing their capability to bioaccumulate REEs and to potentially transfer these contaminants to higher positions in the trophic chain. A spike experiment under controlled conditions was carried out and the intra- and inter-species variability of REEs was monitored in the sponge bodies by ICP-MS. Concentrations were found to be up to 170 times higher than the corresponding control specimens. The tubular species Aplysina cavernicola showed the highest concentrations among the studied species. This study shows, for the first time, the potential of marine sponges as bio-monitor of REEs as well as their possible application in the bioremediation of polluted sites.

The accumulation of human-derived debris in the oceans is a global concern and a serious threat to marine wildlife. There is a volume of evidence that points to deleterious effects of marine debris (MD) on cetaceans in terms of both entanglement and ingestion. This review suggests that about 68% of cetacean species are affected by interacting with MD with an increase in the number of species reported to have interacted with it over the past decades. Despite the growing body of evidence, there is an ongoing debate on the actual effects of plastics on cetaceans and, in particular, with reference to the ingestion of microplastics and their potential toxicological and pathogenic effects. Current knowledge suggests that the observed differences in the rate and nature of interactions with plastics are the result of substantial differences in species-specific diving and feeding strategies. Existing projections on the production, use and disposal of plastics suggest a further increase of marine plastic pollution. In this context, the contribution of the ongoing COVID-19 pandemic to marine plastic pollution appears to be substantial, with potentially serious consequences for marine life including cetaceans. Additionally, the COVID-19 pandemic offers an opportunity to investigate the direct links between industry, human behaviours and the effects of MD on cetaceans. This could help inform management, prevention efforts, describe knowledge gaps and guide advancements in research efforts. This review highlights the lack of assessments of population-level effects related to MD and suggests that these could be rather immediate for small populations already under pressure from other anthropogenic activities. Finally, we suggest that MD is not only a pollution, economic and social issue, but also a welfare concern for the species and populations involved.

Little is known about the main sources of ambient particulate matter (PM) in the 22 Eastern Mediterranean Region (EMR) countries. We designed this study to systematically review all published and unpublished source apportionment (SA), identification and characterization studies as well as emission inventories in the EMR. Of 440 articles identified, 82 (11 emission inventory ones) met our inclusion criteria for final analyses. Of 22 EMR countries, Iran with 30 articles had the highest number of studies on source specific PM followed by Pakistan (n = 15 articles) and Saudi Arabia (n = 8 papers). By contrast, there were no studies in Afghanistan, Bahrain, Djibouti, Libya, Somalia, Sudan, Syria, Tunisia, United Arab Emirates and Yemen. Approximately 72% of studies (51) were published within a span of 2015–2021.48 studies identified the sources of PM₂.₅ and its constituents. Positive matrix factorization (PMF), principal component analysis (PCA) and chemical mass balance (CMB) were the most common approaches to identify the source contributions of ambient PM. Both secondary aerosols and dust, with 12–51% and 8–80% (33% and 30% for all EMR countries, on average) had the greatest contributions in ambient PM₂.₅. The remaining sources for ambient PM₂.₅, including mixed sources (traffic, industry and residential (TIR)), traffic, industries, biomass burning, and sea salt were in the range of approximately 4–69%, 4–49%, 1–53%, 7–25% and 3–29%, respectively. For PM₁₀, the most dominant source was dust with 7–95% (49% for all EMR countries, on average). The limited number of SA studies in the EMR countries (one study per approximately 9.6 million people) in comparison to Europe and North America (1 study per 4.3 and 2.1 million people respectively) can be augmented by future studies that will provide a better understanding of emission sources in the urban environment.

High demands for but strict regulatory measures on Organophosphorus Flame Retardants (OPFRs) have resulted in mainland China transitioning from the region that imports OPRFs to one that exports these substances. Simultaneously, large quantities of terrigenous OPFRs have been exported to adjacent seas by the major river systems, particularly the Yangtze River. This study examined the presence of ten OPFRs in China's adjacent seas. High levels of OPFRs were observed in seas south of mainland China, with Tris (2-chloroethyl) phosphate (TCEP) and Tris (1,3-dichloro-2-propyl) phosphate (TDCPP) dominant. The terrigenous OPFRs were redistributed by the ocean surface currents, with OPFRs tending to accumulate in regions with lower current speed. The producers of OPFRs are mainly distributed along the Haihe, Yellow, and Yangtze river systems. The application of OPFRs to electric vehicle charging stations, charging connectors, and 5G infrastructure in the Chinese mainland will likely drive rapid growth in OPFR related industry in the future. The diffusion trend map of OPFR indicated that the Bohai Sea and the central northern Yellow Sea are at high risk of ecological damage in the spring. The offshore region of the north of the South China Sea tended to aggregate more OPFRs in summer. Regions of the OPFR aggregation effect were at a higher risk of ecological damage.

As the logistics and plate capital of China, the sources and regional transport of O₃ in Linyi are different from those in other cities because of the significant differences in industrial structure and geographical location. Twenty-five ozone pollution episodes (OPEs, 52 days) were identified in 2021, with a daily maximum 8-h moving average O₃ concentration (O₃₋MDA₈) of 184.5 ± 22.5 μg/m³. Oxygenated volatile organic compounds (OVOCs) and aromatics were the dominant contributors to ozone formation potential (OFP), with contributions of approximately 23.5–52.7% and 20.0–40.8%, respectively, followed by alkenes, alkanes, and alkynes. Formaldehyde, an OVOC with high concentrations emitted from the plate industry and vehicles, contributed the most to OFP (22.7 ± 5.5%), although formaldehyde concentrations only accounted for 9.4 ± 2.7% of the total non-methane hydrocarbon (NMHC) concentrations. The source apportionment results indicated that the plate industry was the dominant O₃ contributor (27.0%), followed by other sources (21.6%), vehicle-related sources (18.0%), solvent use (16.9%), liquefied petroleum gas (LPG)/natural gas (NG) (8.8%), and combustion sources (7.7%). Therefore, there is an urgent need to control the plating industry in Linyi to mitigate O₃ pollution. The backward trajectory, potential source contribution function (PSCF), and concentration weighted trajectory (CWT) models were used to identify the air mass pathways and potential source areas of air pollutants during the OPEs. O₃ pollution was predominantly affected by air masses that originated from eastern and local regions, while trajectories from the south contained the highest O₃ concentrations (207.0 μg/m³). The potential source area was from east and south Linyi during the OPEs. Therefore, it is critical to implement regional joint prevention and control measures to lower O₃ concentrations.

Distillery sludge is a major source of aquatic pollution, but little is known about their microbial community and their association with the organic and metal pollutants. Sugarcane molasses-based distillery is an important industry in India, although the waste is usually treated prior to disposal, the treatment is often inadequate. The adverse effects of the organic and metal pollutants in sugarcane molasses-based distillery sludge on the microbial biodiversity and abundance in the disposal site have not been elucidated. This study aims to address this gap of knowledge. Samples were collected from the discharge point, 1 and 2 km downstream (D1, D2, and D3, respectively) of a sugarcane distillery in Uttar Pradesh, India, and their physico-chemical properties characterised. Using QIIME, taxonomic assignment for the V3 and V4 hypervariable regions of 16 S rRNA was performed. The phyla Proteobacteria (28–39%), Firmicutes (20–28%), Bacteriodetes (9–10%), Actinobacteria (5–10%), Tenericutes (1–9%) and Patescibacteria (2%) were the predominant bacteria in all three sites. Euryechaeota, were detected in sites D1 and D2 (1–2%) but absent in D3. Spirochaetes (5%), Sinergistetes (2%) and Cloacimonetes (1%) were only detected in samples from site D1. Shannon, Simpson, Chao1, and Observed-species indices indicated that site D1 (10.18, 0.0013, 36706.55 and 45653.84, respectively) has higher bacterial diversity and richness than D2 (6.66, 0.0001, 25987.71 and 49655.89, respectively) and D3 (8.31, 0.002, 30345.53 and 30654.88, respectively), suggesting the organic and metal pollutants provided the stressors to favour the survival of microbial community that can biodegrade and detoxify them in the distillery sludge. This study confirmed that the treatment of the distillery waste was not sufficiently effective and provided new metagenomic information on its impact on the surrounding microbial community. It also offered new insights into potential bioremediation candidates.

Many technologies have been designed to monitor, evaluate, and improve surface water quality, as high-quality water is essential for human activities including agriculture, livestock, and industry. As such, in this study, we investigated water quality indices (WQIs), trophic status indices (TSIs), and heavy metal indices (HMIs) for assessing surface water quality. Based on these indices, we summarised and compared water assessment models using expert system (ES) and machine learning (ML) methods. We also discussed the current status and future perspectives of water quality management. The results of our analyses showed that assessment indices can be used in three aspects of surface water quality assessment: WQIs are aggregated from multiple parameters and commonly used in surface water quality classification; TSIs are calculated from the concentrations of different nutrients required for algae and bacteria, and employed to evaluate the eutrophication levels of lakes and reservoirs; HMIs are mainly applied for human health risk assessment and the analysis of correlation of heavy metal sources. ES- and ML-based assessment models have been developed to efficiently generate assessment indices and predict water quality status based on big data obtained from new techniques. By implementing dynamic monitoring and analysis of water quality, we designed a next-generation water quality management system based on the above indices and assessment models, which shows promise for improving the accuracy of water quality assessment.

Although biomass fuel has always been regarded as a source of sustainable energy, it potentially emits polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs). This study investigated PCDD/F emissions from industrial boilers fired with three types of biomass fuel (i.e., bagasse, coffee residue, and biomass pellets) via stack sampling and laboratory analysis. The measured mass concentrations of PCDD/Fs varied among the boilers from 0.0491 to 12.7 ng Nm⁻³ (11% O₂), with the calculated average international toxic equivalent quantity (I-TEQ) from 0.00195 to 1.71 ng I-TEQ Nm⁻³ (11% O₂). Some of them were beyond the limit value for municipal waste incineration. 2,3,4,7,8-PeCDF could be used as a good indicator of dioxin-induced toxicity of stack flue gases from biomass-fired boilers. The PCDFs/PCDDs ratios were more than 1, likely indicating the formation of dioxins in the boilers favored by de novo synthesis. The emission factor (EF) of total PCDD/Fs averaged 5.35 ng I-TEQ kg⁻¹ air-dry biomass (equivalent to 39.0 ng kg⁻¹ air-dry biomass). Specifically, the mean EF was 6.94 ng I-TEQ kg⁻¹ (52.6 ng kg⁻¹) for biomass-pellet-fired boiler, 11.8 ng I-TEQ kg⁻¹ (74.6 ng kg⁻¹) for coffee-residue -fired boiler, and 0.0277 ng I-TEQ kg⁻¹ (0.489 ng kg⁻¹) for bagasse-fired boilers. The annual PCDD/F emission was estimated to be 208 g I-TEQ in 2020 in China, accounting for approximately 2% of the total national annual emission of PCDD/Fs. The results can be used to develop PCDD/Fs emission inventories and offer valuable insights to authorities regarding utilizing biomass in industry in the future.

China has been in a rapid development period in recent decades, the mass production and use of chemical industrial products and pesticides have resulted in a large amount of pollutants in the environment. These pollutants enter the human body through environmental exposure and dietary intake, causing adverse health effects. Although many of them have been banned and restricted in the production and use in China, these pollutants still remain in the human body due to their high persistence and strong bioaccumulation. In this review, we aim to reveal the accumulation levels and profiles, as well as the temporal and spatial distribution of common chemical pollutants including chlorinated paraffins (CPs), polycyclic aromatic hydrocarbons (PAHs), organochlorine pesticides (OCPs), polybrominated diphenyl ethers, organophosphorus flame retardants (OPFRs), new halogenated flame retardants (NHFRs), polychlorinated biphenyls, phthalic acid esters, perfluorinated compounds, bisphenols, organophosphorus pesticides and pyrethroid insecticides in the blood (including whole blood, serum and plasma) of Chinese adults by extracting 93 related studies published from 1990 to 2021. Results have shown that CPs, OCPs and PAHs were the main pollutants in China, the levels of short-chain chlorinated paraffin, p,p'-DDE and phenanthrene in blood even reached 11,060.58, 740.41 and 498.28 ng/g lipid respectively. Under the strict control of pollutants in China, the levels of most pollutants have been on a downward trend except for perfluoro octanoate and perfluoro nonanoate. Besides, OPFRs, NHFRs and PAHs may have a potential upward trend, requiring further research and observation. As for spatial distribution, East China (Bohai Bay and Yangtze River Delta) and South China (Pearl River Delta) were the major polluted regions due to their fast development of industry and agriculture.

Trace metal (loid) contamination in the atmosphere is widely monitored, but there is a gap in understanding its long-term patterns, especially in North China, which is currently a global contamination hotspot mainly caused by heavy industry emissions and coal combustion. Herein, historical trends of atmospheric As, Cd, Cr, Cu, Hg, Ni, Pb and Zn contamination in North China over the past ∼500 years are comparatively studied with sediment cores from two subalpine lakes (Gonghai and Muhai). Arsenic, Pb, Cd and Hg were main pollutants according to Pb isotopes and enrichment factors. Mercury contamination has increased continuously since the late 1800s and increasing As, Pb and Cd contamination started in the 1950s in Gonghai. In contrast, the contamination in Muhai lagged two decades for As, Cd and Pb and a half-century for Hg behind that in Gonghai, although the trends were similar. This contamination lag was attributed to the low sensitivity of Muhai sediment to early weak atmospheric metal contamination under 2.1-fold higher detrital sedimentation. As, Pb and Cd contamination has intensified since the 1980s, and the metals showed similar sedimentary fluxes in the cores. However, sedimentary fluxes of Hg contamination were 3.4-fold higher in Gonghai than in Muhai due to combination with organic matter. No obvious Cr, Cu and Ni contamination in the cores was mainly because of the low atmospheric deposition from anthropogenic sources relative to detrital input, although some of their atmospheric emissions were higher than those of As, Cd and Hg. Atmospheric As, Pb and Cd contamination was mainly from domestic sources of coal combustion and nonferrous smelting. Mercury contamination was mainly from global and Asian sources in the first half of the 20th century, and domestic emissions gradually dominated Hg contamination after the mid-1900s.