Heavy metal contamination is an elevating threat to the aquatic environment of estuarine bays. In the present study, surface sediments from Shantou Bay in South China were collected and detected for the concentrations of heavy metals including copper (Cu), zinc (Zn), chromium (Cr), nickel (Ni), cadmium (Cd), and lead (Pb) using ICP-MS. Spatial distribution, temporal trend, and potential ecological risks for the metal pollution were discussed. The results showed that levels of metals generally decreased by the order of Zn > Pb > Cr > Cu > Ni > Cd. Spatial variation of metal contents was observed with an order of Rongjiang River > Niutian Bay > Shanthou Harbor for Zn and Cd. Sediments of the Niutian Bay were observed with higher levels of Cu, Cr, Ni, and Pb. Compared with reported data from the same region at different sampling periods, a low–high–low trend was observed for the concentrations of the six elements, suggesting a great improvement of sediment quality in Shantou Bay. The average I_geo values suggested moderate pollution of Cu, Zn, Pb, and Cd. The potential ecological risks of Cu, Pb, Zn, Ni, and Cr were in low levels. More attention should be paid to the Cd pollution, considering its great values of potential ecological risk index. Our findings provided better understanding of heavy metal pollution in estuarine environments.

In this study, a microbial fuel cell (MFC) that can achieve simultaneous anode anaerobic ammonium oxidation (anammox) and electricity generation (anode anammox MFC) by high-effective anammox bacteria fed with purely inorganic nitrogen media was constructed. As the influent concentrations of ammonium (NH₄⁺-N) and nitrite (NO₂⁻-N) gradually increased from 25 to 250 mg/L and 33–330 mg/L, the removal efficiencies of NH₄⁺-N, NO₂⁻-N and TN were over 90%, 90% and 80%, respectively, and the maximum volumetric nitrogen removal rate reached 3.01 ± 0.27 kgN/(m³·d). The maximum voltage and maximum power density were 225.48 ± 10.71 mV and 1308.23 ± 40.38 mW/m³, respectively. Substrate inhibition took place at high nitrogen concentrations (NH₄⁺-N = 300 mg/L, NO₂⁻-N = 396 mg/L). Electricity production performance significantly depended upon the nitrogen removal rate under different nitrogen concentrations. The reported low coulombic efficiency (CE, 4.09–5.99%) may be due to severe anodic polarization. The anode charge transfer resistance accounted for about 90% of the anode resistance. The anode process was the bottleneck for energy recovery and should be further optimized in anode anammox MFCs. The high nitrogen removal efficiency with certain electricity recovery potential in the MFCs suggested that anode anammox MFCs may be used in energy sustainable nitrogen-containing wastewater treatment.

In the present study, winter jujube organs including fruit, fruiting leaf and foliage leaf, and associated soils in 14 typical orchards in Binzhou City, Shandong Province, China were collected and determined for the mass fractions of Co, Ni, Cu, Zn, and Cd. The mass fractions of Co, Ni, Cu, Zn, and Cd in plant tissues generally showed an order of Cu > Zn > Ni > Co > Cd as well as those in the soils decreased as Zn > Cu > Ni > Co > Cd. The values of single factor index and Nemerow pollution index suggested the jujube fruits were not polluted by heavy metals. Values of estimated daily intake for all the elements were far below their associated acceptable reference values, indicating no health risks would be caused by a single trace element. The results of targeted hazard quotient (THQ) of the metals in the fruits decreased as Cu > Ni > Zn > Cd accompanying total THQ (TTHQ) lower than 1 showing no hazard would be caused by those metals. Correlation analysis showed soil might not be the main source of heavy metals in winter jujube organs. Bioaccumulation factors (BAFs) for Co, Ni, Zn and Cd in fruits and leaves were far below 1 suggesting their low bioavailablities. The relatively great BAFs of Cu in the leaves might be due to the application of fertilizers and pesticides containing great amounts of Cu through soil and foliar spraying. To sum up, heavy metals tended not to be a major threat to winter jujube cultivation, and winter jujube had great edible safety.

With the global proliferation of vehicular transportation, tire wear particles (TWPs) have emerged as a pervasive class of emerging contaminants in the environment. Primarily originating from terrestrial road networks, these anthropogenic particulates undergo complex environmental transport through atmospheric deposition and hydrological processes, ultimately accumulating in marine compartments through seawater column retention, benthic sedimentation, and bioaccumulation within marine trophic webs. The environmental impacts of TWPs manifest through multiple mechanisms including physically effects on marine organisms, chemically leaching of toxic tire components, and ecologically bioaccumulation and biomagnification. Current research priorities emphasize the development of standardized monitoring protocols for TWPs quantification and the implementation of source control strategies through green material engineering. This review systematically examines the environmental fate, ecological impacts, and risk mitigation approaches associated with marine TWPs pollution, providing critical insights for developing evidence-based management frameworks.

Oilfield-wetland zones are ecologically fragile landscapes where petroleum extraction, traffic, and agricultural activities may jointly affect soil metal accumulation. In this study, surface soils from oilfield-wetland patches in the Yellow River Delta were analyzed for Cr, Co, Ni, Cu, Zn, Cd, and Pb, together with selected soil properties. The concentrations of Cr, Co, Ni, Cu, Zn, Cd, and Pb ranged from 47.11 to 106.72, 11.01 to 23.53, 27.61 to 64.28, 6.41 to 60.45, 10.41 to 190.95, ND to 0.37, and 16.53 to 104.58 mg/kg, respectively, and were below the Chinese agricultural soil risk-screening values. Ni exceeded the local background value in all samples, while Pb, Co, Cr, and Cu showed frequent background exceedance, indicating limited enrichment rather than regulatory risk. Spatial differences were element-specific, with Cu differing significantly between Gudao and Xianhe towns and Zn tending to be higher away from oil wells and in vegetated zones. Correlation and PCA results suggested possible influences from both natural processes and anthropogenic activities. Pollution and ecological risk indices indicated low overall risk, but Pb enrichment, consistent Ni background exceedance, and localized Cd-related ecological risk require continued monitoring.