A large portion of the toxic effects observed in surface waters cannot be attributed to compounds regularly measured by water authorities. Hence, there is an urgent need for an effect-based ...monitoring strategy that employs bioassays to identify environmental risks. The aim of the present study was to perform an effect-based nationwide water quality assessment to identify ecotoxicological risks in a wide variety of surface waters. At 45 locations silicone rubbers and polar organic chemical integrative samplers were exposed to surface water for 6 weeks. Alongside the passive samplers an in-situ daphnid test was performed. Subsequent to field exposure, accumulated compounds were extracted from the passive samplers after which a battery of in vivo and in vitro bioassays was exposed to the extracts. The bioassay battery was selected such that it could identify the risks posed by a wide range of chemical pollutants and their transformation products, while simultaneously allowing for targeted identification of groups of compounds that cause specific effects. Bioassay responses were compared to effect-based trigger values to identify potential ecotoxicological risks at the investigated locations. Responses were observed in all bioassays, and trigger values were exceeded in 9 out of the 21 applied assays, allowing for ranking of the investigated locations based on ecotoxicological risks. No relationship between land use and the identification of ecotoxicological risks was observed. Based on the results, considerations regarding future improvements of effect-based monitoring are given. It is concluded that effect-based water quality assessment allowed prioritization of sites based on ecotoxicological risks, identified the presence of hazardous compounds regardless of being listed as priority substances, and meanwhile could prevent costly chemical analysis at sites with low ecotoxicological risks.
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•Responses were observed in all 21 bioassays in a nationwide campaign.•Effect-based trigger values were exceeded for 9 out of 21 bioassays.•Effect-based assessment allowed prioritization based on ecotoxicological risks.•Improvements of effect-based monitoring are proposed.
Over the last years the variety of food and beverage packaging has increased with the development of new plastic materials and (co)polymer modifications. Oligomers which are always present in ...polymers evoke attention as potential migrants, from a qualitatively and quantitatively viewpoint.
This article deals with oligomers as potential migrants from plastics food contact materials and reviews their occurrence as well as analytical methods for their identification and quantification. Additionally a section about migration summarizes literature providing oligomer levels in food simulants and foods. Special attention was given to polycondensates since these represent a rapidly expanding polymer field due to increased numbers of (co)-monomers authorized by the EU.
Evaluating a polymer regarding the content and migration potential of its oligomers several factors like the separation of oligomers from the material, the choice of suitable separation and detection techniques for identification and quantification and the choice of an appropriate standard have to be considered. Generally, MS technologies coupled to liquid chromatography have been shown to represent the analytical approach of choice. This is, so far as the authors are aware of, the first review exclusively focusing on analytical methods for oligomers as polymer specific substances, which suggests to consider them as a separate polymer related and polymer type specific group besides the so-called non-intentionally added substances (NIAS).
•Food contact polymers are sources of different oligomeric structures.•Identification of oligomers using mass spectrometry.•Quantification of oligomers with different analytical approaches.•Oligomers as potential migrants in plastic food contact materials.•Analysis of polymeric additives.
We investigated the occurrence of metal-based nanoparticles in a natural system, the river Dommel in the Netherlands. The river itself is well-studied as far as hydrology and water quality is ...concerned, easily accessible and contains one major wastewater treatment plant discharging onto this river. We sampled water from various locations along the river and collected samples of influent, effluent and sewage sludge from the wastewater treatment plant. The sampling campaign was carried out in June 2015 and these samples were analysed for seven elements using high-resolution inductively coupled plasma mass spectrometry (HR-ICP-MS), ultrafiltration with a sequence of mesh sizes and scanning electron microscopy (SEM).
From the results we conclude that there are indeed nanoparticles present in the treatment plant we studied, as we found titanium and gold particles in the influent and effluent. In the river water only 10 to 20% of the mass concentration of titanium, cerium and other elements we examined is made up of free, i.e. unattached, particles with a size smaller than 20 nm or of dissolved material. The rest is attached to natural colloids or is present as individual particles or clusters of smaller particles, as it could be filtered out with 450 nm ultrafilters.
We found evidence that there is no appreciable anthropogenic emission of cerium into the river, based on the geochemical relationship between cerium and lanthanum. Besides, the effluent of the treatment plant has lower concentrations of some examined elements than the surface water upstream. The treatment plant discharges much less of these elements than estimated using previous publications. However, a potential diffuse source of titanium dioxide in the form of nanoparticles or of larger particles is their use in paints and coatings, as the concentration of titanium increased considerably in the urbanised area of the river Dommel.
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•Ultrafiltration shows that most metal is adsorbed to particles larger than 0.5 μm.•Nanoparticles found in influent and sewage sludge are mainly aggregated.•Estimated concentration of nanoparticles is at most 10% of total metal concentration.•Titanium concentrations may be enhanced due to urban runoff.
Polyfluorinated alkylated substances have recently gained scientific interest because they have been found to be present in appreciable concentrations in human serum, in surface waters, and in ...tissues of wildlife from remote areas. The developments in analytical chemistry of these mainly neutral or anionic surface-active compounds are reviewed in this paper. Problems associated with the determination of polyfluorinated alkylated compounds include diverse aspects such as unique physicochemical properties, lack of reliable standards, impurities, complicated mixtures of isomers and congeners, ion suppression, and contamination during all stages of the analytical procedure, including instrumental sources. State-of the-art analysis involves either direct or ion-paired extraction of the compounds from environmental media, followed by LC-MS(/MS) or GC-MS (for neutral compounds).
The European Reach legislation will possibly drive producers to develop newly designed chemicals that will be less persistent, bioaccumulative or toxic. If this innovation leads to an increased use ...of more hydrophilic chemicals it may result in higher mobilities of chemicals in the aqueous environment. As a result, the drinking water companies may face stronger demands on removal processes as the hydrophilic compounds inherently are more difficult to remove. Monitoring efforts will also experience a shift in focus to more water-soluble compounds. Screening source waters on the presence of (emerging) contaminants is an essential step in the control of the water cycle from source to tap water. In this article, some of our experiences are presented with the hybrid linear ion trap (LTQ) FT Orbitrap mass spectrometer, in the area of chemical water analysis. A two-pronged strategy in mass spectrometric research was employed: (i) exploring effluent, surface, ground- and drinking-water samples searching for accurate masses corresponding to target compounds (and their product ions) known from,
e.g. priority lists or the scientific literature and (ii) full-scan screening of water samples in search of ‘unknown’ or unexpected masses, followed by MS
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experiments to elucidate the structure of the unknowns. Applications of both approaches to emerging water contaminants are presented and discussed. Results are presented for target analysis search for pharmaceuticals, benzotriazoles, illicit drugs and for the identification of unknown compounds in a groundwater sample and in a polar extract of a landfill soil sample (a toxicity identification evaluation bioassay sample). The applications of accurate mass screening and identification described in this article demonstrate that the LC–LTQ FT Orbitrap MS is well equipped to meet the challenges posed by newly emerging polar contaminants.
The presence of perfluoroalkyl substances (PFASs) in sediments and groundwater on the Maltese Islands is reported here for the first time. Sediments and soil samples were collected from 24 sites and ...groundwater was collected from 10 boreholes. PFASs were extracted from water and solid samples using solid phase extraction. The extracts were then analysed using ultra performance liquid chromatography coupled to mass spectrometry in tandem (UPLC-MS/MS). All sediment, soil and groundwater samples were contaminated with at least one PFAS. PFOS (<LOQ – 5.91 ng/g), PFOA (<LOQ – 0.58 ng/g) and PFDA (<LOQ – 1.05 ng/g) were the major PFASs being detected in 100% of the sediment and soil samples. Meanwhile PFOA (<LOD – 2.68 ng/L) was the PFAS detected in all groundwater samples. The concentrations of PFASs observed in groundwater on the Maltese Islands were below the parameters set by the Directive 98/83/EC.
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•Occurrence and distribution of 7 perfluoroalkyl substances in the Maltese soil, sediment and groundwater were investigated.•PFOS, PFOA and PFDA were the most abundant PFASs in soil and sediment with the highest PFAS concentration always being PFOS.•All PFAS analysed were found in groundwater with PFOA being the most abundant.
The presence of perfluoroalkyl substances (PFASs) in rain water on the Maltese Islands is reported here for the first time and an extensive survey of these substances in surface water also reported. ...The Maltese archipelago lies at the centre of the Mediterranean Sea and consists of three main inhabited islands: Malta, Gozo and Comino. Surface water was collected from 41 valleys during the months of February and March 2015 at the peak of the wet season. Rain water was collected during the months of December 2014, February, August, September and October 2015. PFASs were extracted from the water samples using solid phase extraction and the extracts were then analysed using ultra performance liquid chromatography coupled to mass spectrometry in tandem (UPLC-MS/MS). All surface and rain water samples were contaminated with at least one PFAS. PFOS (<LOD – 8.6ng/L) and PFOA (ND – 16ng/L) were the two major PFASs being detected in 100% and 95% of the surface waters respectively. The ΣPFAS concentrations in rain water ranged between 0.38ng/L (1st October 2015) and 6ng/L (21st February 2015). The Maltese archipelago is surrounded by sea and disconnected from any other mainland; therefore the results confirm that remote environments can become contaminated by PFASs from rain events depending on wind prevailing trajectories.
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•The occurrence and distribution of 2 perfluorosulfonates and 5 perfluorocarboxylates in the Maltese surface and rain water were investigated.•PFOA and PFOS were the most abundant PFASs in surface water.•Except for a few samples PFAS concentrations and PFAS composition in precipitation were quite uniform suggesting common sources.•Air masses from source regions yielded rain with higher ƩPFAS concentrations than ones travelling over sea or having rain events prior to sampling.
Legally-prescribed chemical monitoring is unfit for determining the pollution status of surface waters, and there is a need for improved assessment methods that consider the aggregated risk of all ...bioavailable micropollutants present in the aquatic environment. Therefore, the present study aimed to advance effect-based water quality assessment by implementing methodological improvements and to gain insight into contamination source-specific bioanalytical responses. Passive sampling of non-polar and polar organic compounds and metals was applied at 14 surface water locations that were characterized by two major anthropogenic contamination sources, agriculture and wastewater treatment plant (WWTP) effluent, as well as reference locations with a low expected impact from micropollutants. Departing from the experience gained in previous studies, a battery of 20 in vivo and in vitro bioassays was composed and subsequently exposed to the passive sampler extracts. Next, the bioanalytical responses were divided by their respective effect-based trigger values to obtain effect-based risk quotients, which were summed per location. These cumulative ecotoxicological risks were lowest for reference locations (4.3–10.9), followed by agriculture locations (11.3–27.2) and the highest for WWTP locations (12.8–47.7), and were mainly driven by polar organic contaminants. The bioanalytical assessment of the joint risks of metals and (non-)polar organic compounds resulted in the successful identification of pollution source-specific ecotoxicological risk profiles: none of the bioassays were significantly associated with reference locations nor with multiple location types, while horticulture locations were significantly characterized by anti-AR and anti-PR activity and cytotoxicity, and WWTP sites by ERα activity and toxicity in the in vivo bioassays. It is concluded that the presently employed advanced effect-based methods can readily be applied in surface water quality assessment and that the integration of chemical- and effect-based monitoring approaches will foster future-proof water quality assessment strategies on the road to a non-toxic environment.
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•Passive sampling combined with a bioassay battery elucidated ecotoxicological risks.•Methodological improvements led to advancements in effect-based monitoring.•Cumulative ecotoxicological risks increased from reference < horticulture < WWTP.•Bioanalytical responses were location type-specific and driven by polar compounds.•Effect-based methods can readily be applied in surface water quality monitoring.
Exposure science, in its broadest sense, studies the interactions between stressors (chemical, biological, and physical agents) and receptors (e.g. humans and other living organisms, and non-living ...items like buildings), together with the associated pathways and processes potentially leading to negative effects on human health and the environment. The aquatic environment may contain thousands of compounds, many of them still unknown, that can pose a risk to ecosystems and human health. Due to the unquestionable importance of the aquatic environment, one of the main challenges in the field of exposure science is the comprehensive characterization and evaluation of complex environmental mixtures beyond the classical/priority contaminants to new emerging contaminants.
The role of advanced analytical chemistry to identify and quantify potential chemical risks, that might cause adverse effects to the aquatic environment, is essential. In this paper, we present the strategies and tools that analytical chemistry has nowadays, focused on chromatography hyphenated to (high-resolution) mass spectrometry because of its relevance in this field. Key issues, such as the application of effect direct analysis to reduce the complexity of the sample, the investigation of the huge number of transformation/degradation products that may be present in the aquatic environment, the analysis of urban wastewater as a source of valuable information on our lifestyle and substances we consumed and/or are exposed to, or the monitoring of drinking water, are discussed in this article. The trends and perspectives for the next few years are also highlighted, when it is expected that new developments and tools will allow a better knowledge of chemical composition in the aquatic environment. This will help regulatory authorities to protect water bodies and to advance towards improved regulations that enable practical and efficient abatements for environmental and public health protection.
•The role of modern analytical chemistry is essential in exposure science.•Hyphenation of chromatography and HRMS allows the identification of many organic contaminants in the aquatic environment.•Different strategies (target, suspect, non-target) are used for the broad investigation of emerging chemical risks in water.•Monitoring programs and risks assessments are normally focused on parent contaminants.•Little information exists on occurrence and (eco)toxicological effects of transformation products/metabolites in water.
In the past decade during automated surface water monitoring in the river Meuse at border station Eijsden in The Netherlands, a set of unknown compounds were repeatedly detected by online liquid ...chromatography-diode-array detection in a relatively high signal intensity. Because of the unknown nature of the compounds, the consequently unknown fate of this mixture in water treatment processes, the location being close to the water inlet of a drinking water supply company and their possible adverse public health effects, it was deemed necessary to elucidate the identity of the compounds. No data are available for the occurrence of these unknowns at downstream locations. After concentration and fractionation of a sample by preparative Liquid Chromatography, identification experiments were performed using Liquid Chromatography-High Resolution Mass Spectrometry (LC-HR-MS) combined with High Resolution Nuclear Magnetic Resonance Spectroscopy (HR-NMR). Accurate mass determination of the unknown parent compound and its fragments obtained in MS/MS provided relevant information on the elemental composition of the unknown compounds. With the use of NMR techniques and the information about the elemental composition, the identity of the compounds in the different sample fractions was determined. Beside some regularly detected compounds in surface water, like caffeine and bisphenol-S, five dihydroxydiphenylmethane isomers were identified. The major unknown compound was identified as 4,4′-dihydroxy-3,5,3′,5′-tetra(hydroxymethyl)diphenylmethane. This compound was confirmed by analysis of the pure reference compound. This is one of the first studies that employs the combination of high resolution MS with NMR for identification of truly unknown compounds in surface waters at the μg/L level. Five of the seven identified compounds are unexpected and not contained in the CAS database, while they can be presumed to be products generated during the production of resins.
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