Chang-Er Chen- PhD, Lancaster (U.K.)
- Professor at South China Normal University
Chang-Er Chen
- PhD, Lancaster (U.K.)
- Professor at South China Normal University
postdoc wanted, particularly with experiences of Machine Learning.
About
83
Publications
56,537
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Introduction
I am an Environmental Chemists. Research interests include:
Development and applications of passive water sampling techniques; Diffusive Gradients in Thin-films for organics (o-DGT); Machine Learning (ML) in Environmental Sciences; Bioavailability, bioaccumulation and risk assessment of emerging organic pollutants (particularly PFAS, PPCPs) in Environments, WWTPs;
Chemical Regulation and Management.
Contact: changer.chen@m.scnu.edu.cn or changer.chen@live.com
Current institution
Additional affiliations
July 2011 - August 2011
Position
- Visiting PhD student
Description
- Field sampling, SPE and LC-MS/MS for antibiotics
November 2017 - present
Position
- Professor
Description
- I am the PI on Environmental Organic Chemistry, passive sampling, machine learning, bioaccumulation, risk assessment, environmental pollution and health, etc., particularly interested in PFAS since 2018.
March 2016 - February 2018
Position
- Researcher
Description
- Bioaccumulation of natural complex substances (NCSs) and Surfactants.
Education
March 2010 - February 2014
August 2006 - July 2009
September 2002 - July 2006
Publications
Publications (83)
A novel passive water sampler (diffusive gradients in thin-films for organics, o-DGT) was previously developed and successfully tested in the laboratory, but has not yet been validated in the field. Here, o-DGT samplers were deployed in the influent and effluent of a typical UK waste water treatment plant (WWTP), the influent was also sampled with...
Chemicals in mixtures that are hydrophobic with logKow > 4 are potentially bioaccumulative. Here, we evaluate an abbreviated and benchmarked in vivo BCF measurement methodology by exposing rainbow trout to a mixture of eight test chemicals found in fragrance substances and three benchmark chemicals (musk xylene (MX), hexachlorobenzene (HCB) and PCB...
Melamine has received increasing public attention as a persistent, mobile and toxic (PMT) substance. To better assess environmental exposure and risks of melamine and related triazines (cyromazine, ammeline, and atrazine), a new passive sampling method based on the diffusive gradients in thin films (DGT) technique has been developed and validated i...
The physicochemical exchange dynamics between the solid and solution phases of per- and polyfluoroalkyl substances (PFAS) in soils needs to be better understood. This study employed an in situ tool, diffusive gradients in thin films (DGT), to understand the distribution and exchange kinetics of five typical PFAS in four soils. Results show a nonlin...
Traditional methods for identifying endocrine-disrupting chemicals (EDCs) that activate androgen receptors (AR) are costly, time-consuming, and low-throughput. This study developed a knowledge-based deep neural network model (AR-DNN) to predict AR-mediated adverse outcomes on female zebrafish fertility. This model started with chemical fingerprints...
Due to their wide applications, occurrence and “PFAS-like” environmental behaviors, ionic liquids (ILs) represent a new challenge for the environmental monitoring community, who require robust analytical methods that can determine accurately and efficiently their environmentally relevant concentrations. A new passive sampling method based on the di...
Most antibiotics contain ionizable groups that undergo acid-base dissociation giving rise to diverse dissociated forms in aquatic systems depending on the pH of the system. In sunlit surface waters, photochemical transformation plays a crucial role in determining the fate of antibiotics. This study presents a comprehensive examination of the photo-...
With the rapid increase in environmental data, machine learning has become an essential tool for environmental analysis and detection. The main goal of this review is to foster the continuous innovation of this field. In this review, the basic concepts of machine learning, common algorithms and software platforms are briefly introduced. Through a c...
Chemical additives are important components in commercial microplastics and their leaching behaviour has been widely studied. However, little is known about the potential effect of additives on the adsorption/desorption behaviour of pollutants on microplastics and their subsequent role as vectors for pollutant transport in the environment. In this...
To enhance the detection of the escalating presence of per- and poly-fluoroalkyl substances (PFAS) in aquatic environments, the development of innovative sampling techniques becomes imperative. This study focuses on testing a novel passive sampler for in situ sampling of PFAS, employing a ceramic filter tube (CFT) coupled with a hydrogel containing...
Environmental pollution is escalating due to rapid global development that often prioritizes human needs over planetary health. Despite global efforts to mitigate legacy pollutants, the continuous introduction of new substances remains a major threat to both human and ecosystem health. In response, global initiatives are focusing on risk assessment...
The contamination characteristics, migration patterns and health risks of per-and polyfluoroalkyl substances (PFAS) were investigated in 66 Chinese paper products by using target and non-target screening methods. Among 57 target PFASs, 5 and 6 PFASs were found in the hygiene paper products (<LOQ-12.6 ng/g) and stationery paper products (<LOQ-8.8 ng...
Androgen receptor (AR) agonists have strong endocrine disrupting effects in fish. Most studies mainly investigate AR binding capacity using human AR in vitro. However, there is still few methods to rapidly predict AR agonists in aquatic organisms. This study aimed to screen AR agonists of fish species using machine learning and molecular models in...
Effectively identifying persistent organic pollutants (POPs) with extensive organic chemical datasets poses a formidable challenge but is of utmost importance. Leveraging machine learning techniques can enhance this process, but previous models often demanded advanced programming skills and high-end computing resources. In this study, we harnessed...
Wastewater treatment plants (WWTPs) are one of the most important sources and sinks for per-and polyfluoroalkyl substances (PFAS). However, limited studies have evaluated short-term temporal variability of PFAS in WWTPs, particularly for their intra-day variations. For this purpose, a time-composite sampling campaign was carried out at a WWTP influ...
In this study, the effects of manure on the availability of sulfonamide antibiotics (SAs) in soils were explored in situ by the Diffusive gradients in thin films (DGT) technique. Five antibiotics, including sulfadiazine (SDZ), sulfamethoxazole (SMX), sulfamethazine (SMZ), sulfachloropyridazine (SCP), and sulfadimethoxine (SDM), were selected as tar...
Machine learning is increasingly popular and promising in environmental science due to its potential in solving various environmental problems. One such worldwide issue is the pollution caused by the persistent chemicals – per- and polyfluoroalkyl substances (PFAS), threatening the environment and human beings. Here, we introduce a no-code machine...
Perfluoroalkyl substances (PFAS) have been demonstrated to be easily adsorbed on surfaces, which may result in unneglectable measurement error. The adsorption of 10 PFAS with carbon chain lengths varying from 4 to 10 onto 7 types of containers, i.e., stainless steel (SS), alumina, glass, ceramic, polystyrene (PP), polypropylene (PS), and polyethyle...
The extensive use of artificial sweeteners (ASs) has raised concerns regarding their presence, fate, and detrimental effects in water resources. It is thus of great interest for researchers and regulators to acquire a sensitive, robust, and practical sampling technique for monitoring ASs. In the present study, an effective and established passive s...
Phytoremediation is considered an effective technology for remediating antibiotic-contaminated water; however, its underlying mechanisms remain poorly understood. Therefore, this study investigated the phytoremediation potential of fluoroquinolone antibiotics (FQs) by different wetland plant species. The phytoremediation rates of ΣFQs were 46-69 %,...
Organic chemicals associated with microplastics (MPs) can be released and thus pose potential risks during weathering processes. However, the thermodynamics and kinetics of their release processes still need to be better understood. Herein, the adsorption and desorption kinetics of triclosan on polystyrene (PS) and polyvinyl chloride (PVC) were inv...
The diffusive gradients in thin films (DGT) technique is an excellent method for investigating the dynamic processes of antibiotics in soils. However, whether it is applicable in antibiotic bioavailability assessments is yet to be disclosed. This study employed DGT to determine the antibiotic bioavailability in soil, and compared the results with p...
Recent industrial relocation in China causes lots of environment concerns including risks of emerging contaminants (ECs). Herein, the occurrence, fate, removal and ecological risks of 34 per- and polyfluoroalkyl substances (PFAS), 17 endocrine disrupting chemicals (EDCs), 16 phthalate esters (PAEs), and 23 polycyclic aromatic hydrocarbons (PAHs) we...
In response to global climate change, China recently committed to achieving peak carbon emissions by 2030 and carbon neutrality by 2060. Carbon emission reduction should be considered in every sector of society including environmental monitoring. As an energy-saving technique in environmental monitoring, passive sampling has many advantages, such a...
Per- and polyfluoroalkyl substances (PFAS) contamination has drawn considerable attention in the rivers of Shandong, China. However, their seasonal variations have not been well addressed due to the geographic scale. Here, surface waters were collected seasonally at estuaries of 13 major rivers in Shandong to investigate the spatiotemporal variatio...
Plastics gradually degrade in the natural environment from the effect of irradiation, which can change the surface properties of plastics and affect the migration behaviour of pollutants. Up to now, studies on the sorption/desorption behaviour of organic pollutants on aged plastics are still limited. In this study, several types of commercial plast...
Bisphenol A (BPA), 4-nonylphenol (4-NP), and triclosan (TCS) are phenolic endocrine disrupting chemicals (EDCs), which are widely detected in aquatic environments and further bioaccumulated and metabolized in fish. Physiologically based toxicokinetic (PBTK) models have been used to describe the absorption, distribution, metabolism, and excretion (A...
Microplastic pollution in the soil environment has gathered widespread attention. However, little is known about the effects of land use and landscape patterns on the occurrence and distribution of microplastics in the soil. Herein, the microplastic pollution in different land uses (facility farmland, traditional farmland, orchard, grassland, and w...
A method including sample pretreatment and instrumental detection for quantifying 57 per-and polyfluoroalkyl substances (PFAS) in surface water, influent and effluent waters of wastewater treatment plants (WWTPs), sediment and biological samples. Water samples and sediment samples were concentrated and purified by WAX solid phase extraction (SPE) c...
Environmental exposure to active pharmaceutical ingredients
(APIs) can have negative effects on the health of ecosystems and
humans. While numerous studies have monitored APIs in rivers,
these employ different analytical methods, measure different
APIs, and have ignored many of the countries of the world. This
makes it difficult to quantify the sca...
Environmental exposure to active pharmaceutical ingredients (APIs) can have negative effects on the health of ecosystems and humans. While numerous studies have monitored APIs in rivers, these employ different analytical methods, measure different APIs, and have ignored many of the countries of the world. This makes it difficult to quantify the sca...
The passive sampling technique, diffusive gradients in thin films (DGT) has attracted increasing interests as an in-situ sampler for organic contaminants including per-and polyfluoroalkyl substances (PFAS). However, its effectiveness has been questioned because of the small effective sampling area (3.1 cm 2). In this study, we developed a DGT probe...
Emerging organic contaminants (e.g., active pharmaceutical ingredients and personal care products ingredients) are ubiquitous in the environment and potentially harmful to ecosystems, have gained increasing public attention worldwide. Nevertheless, there is a scarcity of data on these contaminants in Africa. In this study, various types of water sa...
Fluoroquinolones (FQs) have raised significant concerns due to their ubiquitous occurrence and promoting of antimicrobial resistance (AMR). In this study, a molecularly imprinted polymer-diffusive gradient in thin-films (MIP-DGT) sampler is developed for selective measurement of FQs in waters by using a commercial available MIP material as the bind...
Denatonium benzoate (DB), a commonly used bitter agent in numerous products, has recently been recognized as a waterborne contaminant due to concern about its potential persistence, mobility and toxicity (PMT). However, its occurrence, levels and fate in global aquatic environments are largely unknown. In this study, a new sampling method, based on...
Poly- and perfluoroalkyl substances (PFASs) are contaminants of global concern. Studies in Pearl River, south China have focused on the delta area, while the upstream contributions are unclear. Here, we systematically investigated the fate, trends and potential sources of 57 PFASs in river water, sediment and fish of the North and West Rivers of the...
Cedarwood oil is an essential oil used as a fragrance material and insect repellent. Its main constituents are sesquiterpenes which are potentially bioaccumulative according to the REACH screening criteria. Cedarwood oil is a complex mixture of hydrophobic and volatile organic chemicals. The volatility and limited water solubility of its constituen...
The occurrence of endocrine disrupting chemicals (EDCs) in the aquatic environment is a global concern. In this study, we employed two different passive samplers Diffusive Gradients in Thin-films (DGT) and Chemcatcher for in situ measurement of 8 phenolic EDCs in the East River of the Pearl River system over one-year. These data were assessed along...
Human activities such as agriculture, aquaculture, and industry can lead to the pollution of coastal waters by trace organic contaminants (TrOCs), and the TrOCs can pose a threat to marine ecosystems. Therefore, it is essential to investigate the occurrence, distribution, and ecological risk of the TrOCs in coastal waters. Previous studies adopting...
The objective of this study was to evaluate the tissue distributions of antibiotics in the fish, the bioaccumulation and trophic transfer in freshwater food web in Taihu Lake, a large shallow freshwater lake. Twenty four out of 41 antibiotics were detected in the biotas of the food web; and antibiotic concentrations followed the orders: fish plasma...
Bisphenol (BP) analogues are widely used as industrial materials and various product additives and are inevitably released into environment. However, knowledge on the sources of different BPs, especially those from urban rainfall runoff to the receiving rivers is very limited. In this study, 15 BPs were determined in surface water, sediments, waste...
Bioaccumulation assessment is important for cationic surfactants in light of their use in a wide variety of consumer products and industrial processes. Since they sorb strongly to natural surfaces and to cell membranes, their bioaccumulation behaviour is expected to differ from other classes of chemicals. Divided over two mixtures, we exposed rainb...
Chemical pollution in the plastic debris is an increasing global concern as most pollutants might transfer from the environment to living organisms via plastic debris. In this study, biocides in the plastic debris floating on the surface water of the Pearl River system were investigated. The abundances of large plastic debris and microplastics in t...
The diffusion coefficient (D) is a key physicochemical parameter for the diffusive gradients in thin films technique (DGT) for environmental sampling, which has been extended to organic chemicals (so called o-DGT). D can be measured in the laboratory, although for organic chemicals this parameter might be predicted based on chemical structure. Here...
Document recommendation systems for locating relevant literature have mostly relied on methods developed a decade ago. This is largely due to the lack of a large offline gold-standard benchmark of relevant documents that cover a variety of research fields such that newly developed literature search techniques can be compared, improved and translate...
It is essential to monitor pesticides in the environment to help ensure water and soil quality. The diffusive gradients in thin-films (DGT) technique can measure quantitative in-situ labile (available) concentrations of chemicals in water, soil and sediments. This study describes the systematic development of the DGT technique for 9 current pestici...
Titanium dioxide nanoparticles (n-TiO2) are among the man-made nanomaterials that are predicted to be found at high concentrations in the aquatic environment. There, they likely co-exist with other chemical pollutants. Thus, n-TiO2 and other chemical pollutants can be taken up together or accumulate independently from each other in prey organisms o...
Background and aims
Ageing is an important factor for controlling selenium bioavailability and toxicity in soil.
Methods
The ageing processes of selenite and selenate in two soils were systematically investigated by adopting diffusive gradients in thin film technique (DGT) and sequential extraction.
Results
Soluble Se was the main fraction (29.3%...
Sulfonamide antibiotics (SAs) are increasingly detected as aquatic contaminants and exist as different dissociated species depending on the pH of the water. Their removal in sunlit surface waters is governed by photochemical transformation. Here we report a detailed examination of the hydroxyl radical (•OH) and singlet oxygen (¹O2) mediated photoox...
Antibiotics are ubiquitous pollutants in aquatic systems and can exist as different dissociated species depending on the water pH. New knowledge of their multivariate photochemical behavior (i.e., the photobehavior of different ionized forms) is needed to improve our understanding on the fate and possible remediation of these pharmaceuticals in sur...
Atrazine (2-chloro-4-ethylamino-6-isopropylamino-1,3,5-triazine) is a worldwide-used herbicide and often detected in agricultural soils and groundwater at concentrations above the permitted limit, because of its high mobility, persistence, and massive application. This study applied pot experiments to investigate the atrazine contents and speciatio...
A novel method for quantitative determination of chlorinated paraffins (CPs) was developed using bromide-anion attachment atmospheric pressure chemical ionization mass spectrometry (APCI-MS). Bromoform was used to enhance ionization of CPs. Near exclusive formation of stable bromide adduct ions ([M+Br]–) enabled accurate detection of individual CP...
Endocrine disrupting chemicals (EDCs) can be released to coastal waters and affect the endocrine system of marine organisms. To monitor their levels in seawaters, a simple, robust passive sampling method, the diffusive gradients in thin-films (DGT) technique, was developed with XDA-1 resin as a binding agent. Six EDCs (including three estrogens, tw...
Widespread use of organic chemicals in household and personal care product (HPCPs) and their discharge into aquatic systems means reliable, robust techniques to monitor environmental concentrations are needed. The passive sampling approach of diffusive gradients in thin-films (DGT) is developed here and demonstrated to provide in situ quantitative...
As coastal waters in many regions of the world have been polluted by organic micro-pollutants such as antibiotics that can promote the development of resistance genes, it is of importance to monitor the levels of antibiotics in coastal waters. For this purpose, a reliable and robust sampling approach based on diffusive gradients in thin films (DGT)...
Fragrance materials are widely used in household and personal care products in applications that can lead to emissions to the aquatic environment. Assessing the potential for fragrance materials to bioaccumulate in fish in in-vivo laboratory studies require a reliable analytical method for determining the concentrations of chemical substances in fi...
Uptake of selenium (Se) by plants largely depend on the availability of Se in soil. Soils and plants were sampled four times within 8 weeks of plant growth in pot experiments using four plant species. Sequential extraction and diffusive gradients in thin-films (DGT) method were employed to measure Se concentrations in potted soils in selenite- or s...
Hydroxylated polycyclic aromatic hydrocarbons (OH-PAHs) are contaminants of emerging concern in the aquatic environment, so it is of great significance to understand their environmental transformation and toxicity. This study investigated the aqueous photochemical behavior of four OH-PAHs, 9-Hydroxyfluorene (9-OHFL), 2-Hydroxyfluorene, 9-Hydroxyphe...
The occurrence of antibiotics in the environment has raised much concern in recent years. Understanding their release, fate and behaviour in the environment is vital to assess potential risks. In this study, a novel passive water sampler - diffusion gradients in thin-films for organics (o-DGT) - was employed to assess the occurrence and removal of...
Thousands of chemicals are commercially produced throughout the world and the total number increases each year. Environmental monitoring is required to access their release to and exposure and effects in the environment. Traditional sampling approaches such as grab and automatic samplings are time/cost consuming and labour intensive. While passive...
Although sorption/desorption of antibiotics in soils affect their mobility and availability, with consequences for risks to the surrounding environment, the dynamics of these processes are not well known. In this study, diffusive gradients in thin films devices suitable for measuring polar organic compounds (o-DGT) were deployed in two soils for a...
Passive water sampling has several advantages over active methods; it provides time-integrated data, can save on time and cost compared to active methods, and yield high spatial resolution data through co-deployment of simple, cheap units. However, one problem with many sampler designs in current use is that their uptake rates for trace substances...
Polybrominated diphenyl ethers (PBDEs) are potential persistent organic pollutants which have raised many concerns in recent years. Research focusing on children exposure to PBDEs is important but insufficient. The levels and patterns of PBDEs in children's plasma from Dalian, China were studied for the first time. Seventeen PBDE congeners (BDE-30,...
Photolysis of deca-bromodiphenyl ether (BDE-209) was investigated in tetrahydrofuran, dichloromethane, isopropanol, acetone, ethanol, methanol, acetonitrile and dimethylsulfoxide. Noticeable differences of the photolytic rates and quantum yields were found in the diverse solvents. Different to the previous deductions, hydrogen donating efficiency a...
A method for the determination of polybrominated diphenyl ethers (PBDEs) in pine needles was developed. Ultrasonic-assisted extraction (UAE) was employed with n-hexane-acetone (1 : 1, v/v), and concentrated H2SO4 and an alumina column were used for cleaning-up the extract of pine needles. The final extract was identified and quantified for the 8 PB...
Questions
Questions (22)
Hi guys,
Recently we tried the TOF MRM function and in the table, we have 9 chemicals in 9 channels/rows (Figure 1). then we acquired the data but found that only 4 MSMS functions/channels appeared in the data file (Figure 2) and the order is the not order in the MRM table. Also found that two or more chemicals fallen in 1 MSMS channel (such as four chemicals in Foundation 1, see Figure 1). what is going on? why did the order change?
Then we use the data to do the quantification with Targetlynx and found out that if chemicals were in two different channels, then targeting does not work (Figure 3). but if only one channel (such as the above channel 1), then it works.
Any idea?
Many thanks.
Chang'er
I am trying to make stock solutions in DMSO or methanol of some cationic surfactants (some are in S-HCl form, some are native form and some in S-Cl/Br form) as high concentration as possible.
But some surfactants are not dissolved in DMSO/methanol at about 2 mg/mL.
Any idea how to improve the solubility? some acid or base?
many thanks.
We have a Superlcowax 10 GC column (30m, 0.2mm, 0.2um) and I am using it for essential oil chemicals analysis as recommended.
I have a-Pinene, beta-Pinene, camphene, careen, limonene, terpinolene and so on as my target chemicals.
I am trying to develop a quantification method of this chemicals on thermos ISQ, currently inject pure standard to identify the peak and looking for SIM ions for later on use.
I have found all other chemicals by full scan, but I cannot find a-Pinene anyhow.
Is this one elute two early?
My GCMS conditions are:
GC injection (PTV), 60°c- 280°C, oven: 50 °C(2min), 10 °C/min to 240, 30 °C/min to 260 (5min). carrier gas (He) flow 1mL/min.
MS transfer line temp 260 °C, Ion source temp: 260, Scan for 40-400.
With this condition, I end up with RT as follow:
Camphene: 4.97
Beta-Pinene 5.23
Carene 5.65
Limonene 6.27
Terpinolene 7.37
…
I suppose a-Pinene will come out before camphene, but I cannot find it, even with very short solvent delay, see the TIC and EIC (attachment):
Any idea?
thanks.
Chang'er
i might design a flow through system, and need control the pH and hardness of the water? anyone has expierence on this? thinking of using buffer dosing and salt, but might need quite a lot. i will use this for fish study, so it is better to have fresh water, instead of just internal circulation.
many thanks in advance.
Hi guys, I am using Masslynx 4.1 with Quanlynx 4.1
I made a mistake that I closed the Summary window in the Quanlynx browswer Screen, but I can not see it even I go to View > Summary Bar.
(the Quanlynx Browser Screen attached)
What is Wrong? Any idea?
many thanks,
chang'er
