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Increasing pressures on natural resources has led to the adoption of water quality standards to protect ecological and human health. Lakes and reservoirs are particularly vulnerable to pressure on water quality owing to long residence times compared with rivers. This has raised the question of how to determine and to quantify the sources of priority chemicals (e.g. nutrients, persistent organic pollutants and metals) so that suitable measures can be taken to address failures to comply with regulatory standards. Contaminants enter lakes waters from a range of diffuse and point sources. Decision support tools and models are essential to assess the relative magnitudes of these sources and to estimate the impacts of any programmes of measures. This paper describes the development and testing of the Source Apportionment Geographical Information System (SAGIS) for future management of 763 lakes in England and Wales. The model uses readily available national data sets to estimate contributions of a number of key chemicals including nutrients (nitrogen and phosphorus), metals (copper, zinc, cadmium, lead, mercury and nickel) and organic chemicals (Polynuclear Aromatic Hydrocarbons) from multiple sector sources. Lake-specific sources are included (groundbait from angling and bird faeces) and hydrology associated with pumped inputs and abstraction. Validation data confirms the efficacy of the model to successfully predicted seasonal patterns of all types of contaminant concentrations under a number of hydrological scenarios. Such a tool has not been available on a national scale previously for such a wide range of chemicals and is currently being used to assist with future river basin planning. [ABSTRACT FROM AUTHOR]

This paper introduces the MAQ (Multi-dimensional Air Quality) model aimed at defining cost-effective air quality plans at different scales (urban to national) and assessing the co-benefits for GHG emissions. The model implements and solves a non-linear multi-objective, multi-pollutant decision problem where the decision variables are the application levels of emission abatement measures allowing the reduction of energy consumption, end-of pipe technologies and fuel switch options. The objectives of the decision problem are the minimization of tropospheric secondary pollution exposure and of internal costs. The model assesses CO 2 equivalent emissions in order to support decision makers in the selection of win-win policies. The methodology is tested on Lombardy region, a heavily polluted area in northern Italy. [ABSTRACT FROM AUTHOR]

The illicit manufacture of methamphetamine (MAP) produces substantial amounts of hazardous waste that is dumped illegally. This study presents the first environmental evaluation of waste produced from illicit MAP manufacture. Chemical oxygen demand (COD) was measured to assess immediate oxygen depletion effects. A mixture of five waste components (10 mg/L/chemical) was found to have a COD (130 mg/L) higher than the European Union wastewater discharge regulations (125 mg/L). Two environmental partition coefficients, KOW and KOC, were measured for several chemicals identified in MAP waste. Experimental values were input into a computer fugacity model (EPI Suite™) to estimate environmental fate. Experimental log KOW values ranged from -0.98 to 4.91, which were in accordance with computer estimated values. Experimental KOC values ranged from 11 to 72, which were much lower than the default computer values. The experimental fugacity model for discharge to water estimates that waste components will remain in the water compartment for 15 to 37 days. Using a combination of laboratory experimentation and computer modelling, the environmental fate of MAP waste products was estimated. While fugacity models using experimental and computational values were very similar, default computer models should not take the place of laboratory experimentation. [ABSTRACT FROM AUTHOR]

The UV filter benzophenone-3 (BP3) has UV photolysis quantum yield Φ BP3 =(3.1±0.3)·10−5 and the following second-order reaction rate constants: with •OH, =(2.0±0.4)·1010 M−1 s−1; with the triplet states of chromophoric dissolved organic matter (3CDOM*), =(1.1±0.1)·109 M−1 s−1; with 1O2, =(2.0±0.1)·105 M−1 s−1, and with CO3 −•, <5·107 M−1 s−1. These data allow the modelling of BP3 photochemical transformation, which helps filling the knowledge gap about the environmental persistence of this compound. Under typical surface-water conditions, direct photolysis and reactions with •OH and 3CDOM* would be the main processes of BP3 phototransformation. Reaction with •OH would prevail at low DOC, direct photolysis at intermediate DOC (around 5mg C L−1), and reaction with 3CDOM* at high DOC. If the reaction rate constant with CO3 −• is near the upper limit of experimental measures (5·107 M−1 s−1), the CO3 −• degradation process could be somewhat important for DOC<1mg C L−1. The predicted half-life time of BP3 in surface waters under summertime conditions would be of some weeks, and it would increase with increasing depth and DOC. BP3 transformation intermediates were detected upon reaction with •OH. Two methylated derivatives were tentatively identified, and they were probably produced by reaction between BP3 and fragments arising from photodegradation. The other intermediates were benzoic acid (maximum concentration ~10% of initial BP3) and benzaldehyde (1%). [ABSTRACT FROM AUTHOR]

Abstract: Previous research on brominated flame retardants (BFRs), including polybrominated diphenyl ethers (PBDEs) has largely focussed on their concentrations in the environment and their adverse effects on human health. This paper explores their transfer from waste streams to water and soil. A comprehensive mass balance model is developed to track polybrominated diphenyl ethers (PBDEs), originating from e-waste and non-e-waste solids leaching from a landfill. Stepwise debromination is assumed to occur in three sub-systems (e-waste, aqueous leachate phase, and non-e-waste solids). Analysis of landfill samples and laboratory results from a solid-liquid contacting chamber are used to estimate model parameters to simulate an urban landfill system, for past and future scenarios. Sensitivity tests to key model parameters were conducted. Lower BDEs require more time to disappear than high-molecular weight PBDEs, since debromination takes place in a stepwise manner, according to the simplified reaction scheme. Interphase mass transfer causes the decay pattern to be similar in all three sub-systems. The aqueous phase is predicted to be the first sub-system to eliminate PBDEs if their input to the landfill were to be stopped. The non-e-waste solids would be next, followed by the e-waste sub-system. The model shows that mass transfer is not rate-limiting, but the evolution over time depends on the kinetic degradation parameters. Experimental scatter makes model testing difficult. Nevertheless, the model provides qualitative understanding of the influence of key variables. [Copyright &y& Elsevier]

Agricultural pesticides can become persistent environmental pollutants. Among many, glyphosate (GLP) is under particular scrutiny because of its extensive use and its alleged threats to the ecosystem and human health. Here, we introduce the first global environmental contamination analysis of GLP and its metabolite, AMPA, conducted with a mechanistic dynamic model at 0.5 × 0.5° spatial resolution (about 55 km at the equator) fed with geographically-distributed agricultural quantities, soil and biogeochemical properties, and hydroclimatic variables. Our analyses reveal that about 1% of croplands worldwide (385,000 km2) are susceptible to mid to high contamination hazard and less than 0.1% has a high hazard. Hotspots found in South America, Europe, and East and South Asia were mostly correlated to widespread GLP use in pastures, soybean, and corn; diffuse contributing processes were mainly biodegradation recalcitrance and persistence, while soil residue accumulation and leaching below the root zone contributed locally to the hazard in hotspots. Hydroclimatic and soil variables were major controlling factors of contamination hotspots. The relatively low risk of environmental exposure highlighted in our work for a single active substance does not rule out a greater recognition of environmental pollution by pesticides and calls for worldwide cooperation to develop timely standards and implement regulated strategies to prevent excess global environmental pollution. Unlabelled Image • Glyphosate use worldwide is controversial for its potential negative effects on human and environmental health. • Currently, there is no global-scale assessment of glyphosate use and environmental contamination risk. • We have linked our new PEST-CHEMGRIDS global spesticide use database and our BRTSim model to predict glyphosate dynamics over global croplands. • We have quantified biodegradation, soil residue accumulation, runoff potential, leaching to aquifers, and persistence • Low but pervasive contamination occurs in croplands globally; a few geographic hotspots have mid to high contamination hazard [ABSTRACT FROM AUTHOR]

Several laboratory studies have demonstrated that exposure to oil components cause toxicity to copepods, however, this has never been shown in natural populations of copepods. In the present study, we sampled copepods in an area of the North Sea with high density of oil production platforms discharging produced water. Environmental modelling was used to predict produced water and copepod trajectories prior to copepod sampling in situ. To maximise output from a minimal number of field samples, a novel and combined methodology was developed to allow exploitation of the same extract for several purposes; contaminant body burden, lipidomics, and metabolomics analysis. PAH body burdens were low compared to laboratory experiments where correlations between PAH body burden and acute toxicity, reproduction and molecular endpoints had been established. Still, station-specific PAH profiles strongly indicated copepod exposure to PW. NMR metabolomics, focusing on water-soluble metabolites, suggested no correlation between metabolites and stations. Interestingly, lipidomics analyses suggested site-specific fingerprints and profiles displayed for acyl-glycerols and wax esters. Potential effects of produced water exposure on lipid metabolism in copepods cannot be ruled out and deserves more attention. Our study exemplifies the importance of incorporating novel and improved analytical methodologies in environmental monitoring. Unlabelled Image • A novel method was developed where copepod samples were serially extracted for different analytical platforms and endpoints. • Marine copepods sampled offshore close to oil production platforms displayed location-specific PAH and lipid profiles. • Potential effects of produced water exposure on copepod lipid metabolism deserves more attention. [ABSTRACT FROM AUTHOR]