With the technological advances and economic development, the multiplicity and wide variety of applications of electrical and electronic equipment have increased, as well as the amount of end-of-life products (waste of electrical and electronic equipment, WEEE). Accompanying their increasing application, there is an increasing risk to aquatic ecosystems and inhabiting organisms. Among the most common elements present in WEEE are rare earth elements (REE) such as Dysprosium (Dy). The present study evaluated the metabolic and oxidative stress responses of mussels Mytilus galloprovincialis exposed to an increasing range of Dy concentrations, after a 28 days experimental period. The results obtained highlighted that Dy was responsible for mussel’s metabolic increase associated with glycogen expenditure, activation of antioxidant and biotransformation defences and cellular damage, with a clear loss of redox balance. Such effects may greatly impact mussel’s physiological functions, including reproduction capacity and growth, with implications for population conservation. Overall the present study pointed out the need for more research on the toxic impacts resulting from these emerging pollutants, especially towards marine and estuarine invertebrate species.

Ozone has become a major atmospheric pollutant in China as the pattern of urban energy usage has changed and the number of motor vehicles has grown rapidly. The Beijing-Tianjin-Hebei Urban Agglomeration, also known as the Jing-Jin-Ji Urban Agglomeration (hereafter, JJJUA), with a precarious balance between protecting the ecological environment and sustaining economic development, is challenged by high levels of ozone pollution. Based on ozone observation data from 13 cities in the JJJUA from 2014 to 2017, the spatio-temporal trends in the evolution of ozone pollution and its associated influencing factors were analyzed using Moran’s I Index, hot-spot analysis, and Geodetector using ArcGIS and SPSS software. Five key results were obtained. 1) There was an increase in the annual average ozone concentration, for the period 2014–2017. Comparing the 13 prefecture-level cities, ozone pollution in Chengde and Hengshui decreased, while it worsened in the remaining 11 cities. 2) Ozone pollution was worse in spring and summer than in autumn and winter; the peak ozone pollution season was from May to September; the average ozone concentration on workdays was higher than that on non-workdays, showing a counter-weekend effect. 3) Annual average concentrations were high in the central and southern parts of the study region but low in the north. 4) Prominent positive spatial correlations were observed in ozone concentration, with the best correlations shown in summer and autumn; concentrations were high in Baoding and Xingtai but low in Beijing and Chengde. 5) Concentrations of PM10, NO2, CO, SO2, and PM2.5, as well as average wind speed, sunshine duration, evaporation, precipitation, and temperature, all had significant effects on ozone pollution, and interactions between these influencing factors increased it.

Atmospheric pollution could significantly alter tree growth independently and synergistically with meteorological conditions. North China offers a natural experiment for studying how plant growth responds to air pollution under different meteorological conditions, where rapid economic growth has led to severe air pollution and climate changes increase drought stress. Using a single aspen clone (Populus euramericana Neva.) as a ‘phytometer’, we conducted three experiments to monitor aspen leaf photosynthesis and stem growth during in situ exposure to atmospheric pollutants along the urban-rural gradient around Beijing. We used stepwise model selection to select the best multiple linear model, and we used binned regression to estimate the effects of air pollutants, atmospheric moisture stress and their interactions on aspen leaf photosynthesis and growth. Our results indicated that ozone (O₃) and vapor pressure deficit (VPD) inhibited leaf photosynthesis and stem growth. The interactive effect of O₃ and VPD resulted in a synergistic response: as the concentration of O₃ increased, the negative impact of VPD on leaf photosynthesis and stem growth became more severe. We also found that nitrogen (N) deposition had a positive effect on stem growth, which may have been caused by an increase in canopy N uptake, although this hypothesis needs to be confirmed by further studies. The positive impact of aerosol loading may be due to diffuse radiation fertilization effects. Given the decline in aerosols and N deposition amidst increases in O₃ concentration and drought risk, the negative effects of atmospheric pollution on tree growth may be aggravated in North China. In addition, the interaction between O₃ and VPD may lead to a further reduction in ecosystem productivity.

The Pacific Island Countries and Territories (PICTs) are heavily dependent on the marine resources for food security, employment, government revenue and economic development, hence the concern about the potential exposure of these resources to pollutants. The main goal of this review was to identify ecotoxicology studies published that were done in PICTs. Four major gaps were identified: i) a quantitative gap, with low number of studies published on the PICTs; ii) a geographic gap, where ecotoxicology studies have unevenly covered the different PICTs; iii) a temporal gap, as no biological effect monitoring study has so far been published for the PICTs; and, iv) a pollutants gap, as all of the PICTs studies focused mainly on environmental monitoring studying on average two types of pollutants (heavy metals and pesticides) per PICT only. We suggest, therefore, the potential risk to the marine environment to be estimated by assessing the fate of pollutants via chemical and biological effect monitoring.

In this study, we investigated the historical variation, source identification, and distribution of heavy metal pollution in sediments of the Pearl River Estuary (PRE) using ²¹⁰Pb dating. Our results suggest that the heavy metal concentrations were higher in the western part of the estuary. For all heavy metals, Cd was significantly enriched in the sediments. The Pearl River Delta (PRD) has experienced rapid economic development in the past 40 years, a decreasing trend in heavy metal fluxes after 2004 was identified, which suggests a reduction in heavy metal concentrations due to the removal of heavy polluting industries and the effective control of sewage discharge. A binary mixing model reveals that the contributions of anthropogenic Pb ranged from 45.4 to 64%. Based on lead isotopic ratios (²⁰⁶/²⁰⁷Pb and ²⁰⁸/²⁰⁶Pb), it was found that geologic materials and industrial pollution were the main sources of heavy metals in the PRE sediments.

Over the past 40 years since China’s reform and opening up, the industrial structure has undergone tremendous changes. The rapid development of the economy has been accompanied by a surge in carbon emissions. How to achieve a win-win situation for economic growth and carbon emissions reduction has aroused widespread concern from all sectors of society. Here, this paper discusses the dynamic relationship of industrial structure upgrading, economic growth, and carbon emission reduction. Results show that there is a long-term equilibrium relationship among industrial structure upgrading, economic growth, and carbon emissions. In the short term, when the three variables deviate from the long-term equilibrium state, the non-equilibrium state will be pulled back to equilibrium with the adjustment strength of − 0.0633, − 0.0097, and 0.0013. Carbon emission reduction promotes industrial structure upgrading. Industrial structure upgrading has a greater positive impact on economic growth. Industrial structure upgrading and economic growth have a negative impact on carbon emissions, thereby promoting emission reduction. And at the 10% significance level, there is a one-way Granger causality from carbon emissions to industrial structure upgrading, economic growth can cause one-way changes in carbon emissions, and industrial structure upgrading is a one-way Granger cause of economic growth. Finally, several carbon emission reduction policies are proposed promote industrial restructuring and sustainable economic development.

The nexus of remittances and CO2 emission is very important and gathers a significant place in empirical research. This paper tries to find out the asymmetric relationship between carbon emissions, remittances, and financial development in India for the period 1980–2014. Based on the theoretical linkages, we develop a nonlinear ARDL model with the use of time series data in this study. The results of the NARDL bound test suggest that there is long-run cointegration among the variables. The findings show that positive shock in remittances causes an increase in CO2 emissions, where negative shock reduces it. The coefficient for financial development is positive but becomes statistically insignificant. Empirical results also support the existence of asymmetric long-run relationship among the variables. Based on the findings, the paper recommends the proper channelization of remittances and financial development towards environment-friendly energy sources and projects without compromising economic growth.

This study investigates the causal connection between economic growth, foreign direct investment, primary and renewable energy utilization, trade openness, and ecological footprint for 33 upper-middle-income countries (UMICs) from Africa, Asia, Europe, and America during the period from 1994 to 2017. Initially, first- as well as second-generation panel unit root tests are applied to check the integration order after confirming the cross-sectional dependency and heterogeneity. Four different tests (FMOLS, DOLS, FGLS, and AMG) are applied to estimate the long-run elasticity, whereas Dumitrescu and Hurlin (D-H) non-causality test is used to test growth, conservation, and feedback hypothesis. Results show negative relationship of economic growth on ecological footprint in Africa and Europe; renewable energy utilization in Asia, Europe, and America; and trade openness in Asia. Moreover, the results revealed an adverse impact of trade openness on ecological footprint in case of Africa and America. Furthermore, the results of D-H panel non-causality test confirm the growth hypothesis for economic growth to ecological footprint in Africa, Asia, and Europe; foreign direct investment to ecological footprint in Africa and Asia; primary energy utilization to ecological footprint in Asia; renewable energy utilization to ecological footprint in America; and trade openness to ecological footprint in Africa, Asia, and America. Furthermore, the feedback hypothesis was confirmed between economic growth and ecological footprint in Asia and Europe; foreign direct investment and ecological footprint in Africa and Asia; renewable energy utilization and ecological footprint for America; and trade openness and ecological footprint for Asia and America. Finally, in context to efficient policy implications, it is suggested to associate the economic growth with clean energy and environment-friendly technologies by expanding the share of renewable energy in America and economic growth in Africa and Europe. Furthermore, Asian policy makers need to focus on foreign direct investment and trade openness by using green energy to overcome the environmental degradation. Impulsion with these findings, the central authorities of UMICs need to focus on more investments in environmental quality not only through foreign direct investment but also exchanging their clean energy technologies through trade policies such as tax exemption, feed-in tariffs, and subsidies. Government of these countries ought to upgrade the conventional capital which will ultimately improve the human lives by providing clean environment.

Vigorously developing high-tech industry has been considered to be an effective way to coordinate economic growth with excessive carbon dioxide (CO₂) emissions. However, previous studies have not explored the heterogeneous impacts of high-tech industry on CO₂ emissions in regions with different levels of high-tech industry development, and not distinguished the direct and indirect impacts. Based on STIRPAT model, this study investigates the impacts of high-tech industry development on CO₂ emissions in China between 2005 and 2016. Adopting the K-medians cluster method, effects in regions with high, middle, and low levels of high-tech industry development are considered. Indirect effects of high-tech industry development on CO₂ emissions by affecting industry structure upgrades and economic growth are explored. Empirical results illustrate a positive U-shaped nonlinear link between the level of high-tech industry development and CO₂ emissions at the national level and regional (high, middle, and low) level. In terms of indirect impacts, high-tech industry development attenuates the reduction of CO₂ emissions due to industry structure upgrades, and promotes economic growth to increase CO₂ emissions slightly. The indirect impact intensity gradually decreases as the level of high-tech industry development decreases across three regions. Reasonable implications of our findings are proposed.

Air pollution has an important impact on both human health and sustainable economic development. The relationship of the current account, which is an important carrier of international economic activity, with air pollution has rarely been discussed by scholars. This paper aims to investigate how air pollution affects the current account and the mechanism of this effect. We conducted a theoretical analysis of the relationship between air pollution and the current account by adopting an extended form of the life-cycle model. Then, we used panel data (2000–2017) from 159 countries and the panel double fixed-effect method to empirically test the theoretical outcomes. We found that an increase in the degree of air pollution in a country leads to the deterioration of the domestic current account. In addition, air pollution changes the current account by affecting the demographic structure, following the “air pollution→demographic structure→current account” mechanism. The study also tested the robustness of the benchmark results by solving endogeneity problems, subsample regression and controlling measurement errors. Our findings are an important expansion and innovation for the research about the current account and have important implications for external economic equilibrium and sustainable economic development.