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Microplastics are plastic particles which are widely distributed in the environment. The pollution of microplastics in environment have attracted increasing attention in recent years. This paper reviews research progress in sources, analytical methods, eco-environmental effects and control in environment, and suggests relevant countermeasures in governance and research. Microplastics mainly originate from two sources: firstly, a significant direct input of primary microplastics; second, secondary microplastics generate from the fragmentations of larger plastic materials. The analysis and identification of microplastics are critical to other researches, and related instrument methods have also been applied to the analysis and identification of microplastics. The advantages and disadvantages of microplastics analytical methods were reviewed. The eco-environmental effects of microplastics can be divided into four aspects: adsorption, biological uptake, ecotoxicological and combined pollution. Control measures need to strengthen the systematic research of microplastics pollution control and management technology system from the aspects of organizational cooperation, technological research and development, laws and regulations. In the future, a unified quantitative analysis method for microplastics should be established, and more accurate traceability analysis techniques should be developed to further explore its environmental behavior and fate. To strengthen scientific research on microplastic pollution in terrestrial, freshwater and atmospheric environments, and develop more scientific and rational control policies. This paper aims to provide a theoretical basis for the prevention and control of microplastics pollution, and also provides insights for the next step of research.

A geochemical-environmental mapping was carried for a low polluted forest in North-western Mexico (Santiago Papasquiaro mining area), as part of the North American forests accounting for environmental behavior of arsenic (As), lead (Pb), zinc (Zn) and copper (Cu) in soil and tree components (stem wood and aciculums). Spectroscopic and microscopic techniques along with standard protocols were used to determine the mineralogical phases containing these elements, and their corresponding spatial distributions in soil and forests and mobility. In soil, total As, Pb, Zn and Cu ranged from 4.9 to 98.3, 19.6 to 768.6, 19.6 to 407.1, and 1.6 to 63.8 mg kg−1, respectively. Ultrafine particles (

There is very little information on the levels and particle size distributions of lower chlorinated dibenzo-p-dioxins and dibenzofurans (mono- to tri-CDD/Fs, ΣCl1-3DD/Fs) in the atmosphere, while a number of studies have examined tetra- to octa-chlorinated homologues (ΣCl4-8DD/Fs). In this study, we measured the concentration and particle size distribution of ΣCl1-3DD/Fs in ambient air in suburban Beijing and compared them with that of ΣCl4-8DD/Fs for the first time. The mean concentration of ΣCl1-3DD/Fs was 54.63 pg m(-3), which is about 5.4 times that of ΣCl4-8DD/Fs. The ΣCl1-3DD/Fs accounted for 85% of ΣCl1-8DD/Fs, and MoCDFs made up the largest proportion (43%) of PCDD/F homologues. The ΣCl1-3DD/Fs mainly occurred in the gas phase, while the ΣCl4-8DD/Fs mainly occurred in the particulate phase. The majority of ΣCl1-3DD/Fs (70%) occurred in dae > 1.0 μm particles, which is the reverse of the trend observed for ΣCl4-8DD/Fs, of which 78% occurred in dae

With the ever-increasing development on novel chemicals and materials, with radically different properties and environmental behavior, it is challenging to compare their environmental behavior under similar conditions. For example, pesticides may be non-ionizable organics, ionizable organics, metal ion-based, or nanomaterials. These very different chemicals behave very differently. To date, no single modeling platform can handle all adequately, in a dynamic framework that accounts for actual variability in meteorology, rates of release to the environment, and the actual characteristics of the region of interest. Here we present ChemFate, a framework to address this challenge, by incorporating four different fate and transport models, each to address these four classes of chemicals (non-ionizable organics, ionizable organics, metal ion-based, or nanomaterials). We build upon established models, but have incorporated a number of additional processes. After demonstrating that the individual models comparable favorably with observed data and the previous models, under similar conditions, we conducted a case study with four radically different fungicides, used in the Central Valley, California. We found that although the concentrations of the non-ionizable and ionizable organic fungicide spike after application and temporarily may exceed toxicity thresholds for Daphnia Magna, they do not accumulate over time, while the metal ion and metallic nanoparticle result in increasing accumulation of Cu2+, eventually exceeding the toxicity threshold during runoff events. This case study demonstrates the value of a framework that allows the comparison of different classes of chemicals under the same conditions.

Contamination by per- and polyfluoroalkyl substances (PFASs) is of great concern in global environments. Due to strong regulation of legacy PFASs, emerging PFASs including alternatives and precursors have been introduced to the industrial market. In this study, legacy and emerging PFASs were measured in seawater, sediment, and bivalves collected along the Korean coast to investigate the occurrence, distribution, contamination sources, and bioaccumulation potential of PFASs. Wide concentration ranges of legacy PFASs were detected in multiple environmental samples, indicating widespread contamination. C8-based PFASs (e.g., PFOA and PFOS) were still major contaminants in all of the environmental samples. Some precursors, such as 8:2 fluorotelomer sulfonate (8:2 FTS) and N-ethyl-perfluorooctane sulfonamidoacetic acid (N-EtFOSAA), and perfluoro-2-propoxypropanoic potassium 9-chlorohexadecafluoro-3-oxanonane-1-sulfonate (F-53B), an alternative to PFOS, were detected in sediment or bivalve samples, implying a shift in consumption patterns from legacy to emerging PFASs. The highest concentrations of PFASs in environmental samples were found at the locations near industrial complexes, such as those for the semi-conductor, paper mill, automobile, and metal-plating industry. This result indicates that PFAS contamination is associated with intensive industrial activities in the coastal environment. Matrix-dependent contamination and profiles of PFASs were observed. Seawater was dominated by short-chained PFASs as a prompt reflection of regulation, while the sediment and bivalves were dominated by long-chained PFASs. Carbon-chain length was a major factor governing environmental behavior and bioaccumulation of PFASs. This was the first nation-wide survey on legacy and emerging PFASs in the coastal environment of Korea.

The presence of neoformed cement-like phases during the weathering of non-stabilized freshly quenched bottom ash favours the development of a bound pavement material with improved mechanical properties. Use of weathered and freshly quenched bottom ash mix layers placed one over the other allowed the retention of leached heavy metals and metalloids by means of a reactive percolation barrier. The addition of 50% of weathered bottom ash to the total subbase content diminished the release of toxic species to below environmental regulatory limits. The mechanisms of retention and the different processes and factors responsible of leaching strongly depended on the contaminant under concern as well as on the chemical and physical factors. Thus, the immediate reuse of freshly quenched bottom ash as a subbase material in road constructions is possible, as both the mechanical properties and long-term leachability are enhanced.

The environmental behavior and pollution status of nickel (Ni) were investigated in seven major cities in Korea over a 13-year time span (1998–2010). The mean concentrations of Ni measured during the whole study period fell within the range of 3.71 (Gwangju: GJ) to 12.6 ng m −3 (Incheon: IC). Although Ni values showed a good comparability in a relatively large spatial scale, its values in most cities (6 out of 7) were subject to moderate reductions over the study period. To assess the effect of major sources on the long-term distribution of Ni, the relationship between their concentrations and the potent source processes like non-road transportation sources (e.g., ship and aircraft emissions) were examined from some cities with port and airport facilities. The potential impact of long-range transport of Asian dust particles in controlling Ni levels was also evaluated. The overall results suggest that the Ni levels were subject to gradual reductions over the study period irrespective of changes in such localized non-road source activities. The pollution of Ni at all the study sites was maintained well below the international threshold (Directive 2004/107/EC) value of 20 ng m −3 .

International audience; Following legislation, the assessment of the environmental risks of 30 000 to 100 000 chemical substances is required for their registration dossiers. However, their behavior in the environment and their transfer to environmental components such as water or atmosphere are studied for only a very small proportion of the chemical in laboratory tests or monitoring studies because it is time-consuming and/or cost prohibitive. Therefore, the objective of this work was to develop a new methodology, TyPol, to classify organic compounds, and their degradation products, according to both their behavior in the environment and their molecular properties. The strategy relies on partial least squares analysis and hierarchical clustering. The calculation of molecular descriptors is based on an in silico approach, and the environmental endpoints (i.e. environmental parameters) are extracted from several available databases and literature. The classification of 215 organic compounds inputted in TyPol for this proof-of-concept study showed that the combination of some specific molecular descriptors could be related to a particular behavior in the environment. TyPol also provided an analysis of similarities (or dissimilarities) between organic compounds and their degradation products. Among the 24 degradation products that were inputted, 58% were found in the same cluster as their parents. The robustness of the method was tested and shown to be good. TyPol could help to predict the environmental behavior of a "new" compound (parent compound or degradation product) from its affiliation to one cluster, but also to select representative substances from a large data set in order to answer some specific questions regarding their behavior in the environment.

Knowledge of the environmental behavior of chemicals is a fundamental part of the risk assessment process. The present paper discusses various methods of ranking of a series of persistent organic pollutants (POPs) according to the persistence, bioaccumulation and toxicity (PBT) characteristics. Traditionally ranking has been done as an absolute (total) ranking applying various multicriteria data analysis methods like simple additive ranking (SAR) or various utility functions (UFs) based rankings. An attractive alternative to these ranking methodologies appears to be partial order ranking (POR). The present paper compares different ranking methods like SAR, UF and POR. Significant discrepancies between the rankings are noted and it is concluded that partial order ranking, as a method without any pre-assumptions concerning possible relation between the single parameters, appears as the most attractive ranking methodology. In addition to the initial ranking partial order methodology offers a wide variety of analytical tools to elucidate the interplay between the objects to be ranked and the ranking parameters. In the present study is included an analysis of the relative importance of the single P, B and T parameters.

The environmental behavior of gaseous elemental mercury (Hg) in the ambient air was investigated from the center of a municipal landfill site (area ∼0.6 km2) located in Dae Gu, Korea in the winter of 2004. In order to provide insight on the Hg exchange processes in strong source areas, we continuously analyzed Hg concentration gradients developed across two heights between 1 m and 5 m over soil surfaces at hourly intervals. The results displayed Hg concentrations in the lower and upper levels in the range of 1.46–13.1 ng m−3 (3.33 ± 1.29 ng m−3: N = 139) and 1.20–13.7 ng m−3 (3.27 ± 1.23 ng m−3: N = 139), respectively. The results of our analysis, when divided separately into emission and dry deposition, showed that emission of Hg was fairly dominant in frequency (up to 58%) over dry deposition. By multiplying our Hg gradient data with the K-values predicted indirectly from the results of previous studies, the emission and deposition fluxes of Hg were estimated as 39.0 ± 43.3 ng m−2 h−1 (N = 80) and −60.0 ± 80.2 ng m−2 h−1 (N = 59), respectively. Although the magnitudes of exchange were moderately lower than previously investigated anthropogenic sources, the overall results of this study suggest that an active landfill site can act as an important source of Hg in an urban environment along with other man-made activities.

An increasing number of organic compounds detected today in the aquatic environment are ionizable and, therefore, partially or permanently charged (ionic) under the pH conditions encountered in these systems. For evaluating their environmental behavior, which strongly depends on the charge state, the identification of functional groups together with their correct assignment of the respective acidic or basic dissociation constants (pKa) is essential. Despite the growing concern and increasing awareness for ionizable compounds, contradicting and/or confusing information regarding their acid/base properties can be regularly found in the literature, especially when complex structures are encountered. Therefore, we provide a simplified, general, and comprehensive guideline for the identification of ionizable functional groups in organic compounds combined with the correct assignment of their respective pKa values. Beside the explicit definition of basic terms, several tables with more than 30 of the most frequently encountered ionizable compound classes, including their typical pKa value ranges are the centerpiece of the proposed procedure. The straight forward application of the guideline is successfully shown for several environmentally relevant compounds as example.

Lindane, a highly persistent and lipophilic pesticide, is still used in large quantities. This chemical can be found with appreciable concentrations in biota, atmosphere, and in other environmental compartments in the adsorbed form. This information provided a basis for assessing the simulation performances of CHEMFRANCE, a regional level III fugacity model allowing to generate environmental behavior profile of organic chemicals in France. The comparison between the estimated environmental fate and field and laboratory observations suggests that this fugacity model can be used to determine the processes that control the environmental fate of lindane in France. CHEMFRANCE also provides accurate estimates of environmental compartment contaminations.

Biodegradation behavior of nonylphenol polyethoxylates (NPEOs) under Fe(III)-reducing conditions was investigated. The study demonstrated that NPEOs could be rapidly biodegraded under Fe(III)-reducing conditions. Almost 60% of the total NPEOs were removed within three days and the maximum biodegradation rate was 34.95 ± 0.84 μM d −1 . NPEOs were degraded via sequential removal of ether units under Fe(III)-reducing conditions. No nonylphenol polyethoxy-carboxylates (NPECs) were formed in this process. This ether removal process was coupled to Fe(III) reduction. Nonylphenol (NP), nonylphenol monoethoxylate (NP1EO), and nonylphenol diethoxylate (NP2EO) slightly accumulated in the anaerobic biodegradation process. The accumulation of these estrogenic metabolites led to a significant increase in the estrogenic activity during the biodegradation period. The calculated estrogenic activity reached its top on day 14 when the total concentration of these estrogenic metabolites was maximal. This is the first report of the primary biodegradation behavior of NPEOs under Fe(III)-reducing conditions. These findings are of major environmental importance in terms of the environmental behavior of NPEO contaminants in natural environment.

In this study, the environmental behavior of two major airborne pollutants, ozone and nitrogen dioxide, was investigated with respect to their exceedance patterns of air quality criteria. For this purpose, we used data sets collected from a total of 31 air quality monitoring stations dispersed across the Seoul metropolitan city between 1990 and 2000. In the case of NO 2 , the frequency of hourly exceedance data sets exhibited little changes in the early 90s. However, it increased dramatically after 1995, probably in compliance with a rapid increase in the total number of automobiles. Likewise, the daily exceedance of O 3 in the early 90s was not significant, approaching 100 cases (except in 1994). However, its total quantity began to surpass 300 cases since around 1996. Comparison of those exceedance data was also made among spatially divided data groups. In the case of NO 2 , the occurrence of exceedance data was dominated by the western part of the city in both magnitude and frequency. On the other hand, that for O 3 was characterized by notably strong occurrences in the eastern counterpart. The overall results of our analysis of the NO 2 and O 3 exceedance data sets indicate an inextricable linkage between the two pollutants in association with geographical and meteorological factors.

A Level III fugacity model is presented (which can be used in the form of a micro-computer program) to calculate the behavior of a chemical which is subject to steady state partitioning, reaction, advection and intercompartmental transfer in a evaluative environment consisting of six compartments, air, soil, water, bottom and suspended sediments and fish. The model is applied to 14 chemicals of varying properties and is shown to generate behavior profiles which are consistent with the reported fate of the respective chemicals in the real environment. Since this single model generates a set of consistent behavior profiles, it is suggested that it may be useful for predicting the behavior of chemicals for which no environmental observations yet exist. Environmental processes which are still inadequately treated by the model are discussed with a view to later improving the model's predictive reliability.