Environmental context. 4-tert-Butylphenol, an environmental endocrine disruptor, can be taken in by humans and animals resulting in reproductive and developmental problems. We report a theoretical study on the degradation mechanism of 4-tert-butylphenol in the atmosphere, and calculate the atmospheric lifetime of this chemical. The data will help our understanding of the behaviour of 4-tert-butylphenol in the environment and thereby provide valuable information about its possible effect on human health.

Environmental context. The increasing use of sun-creams containing UV-filtering chemicals has led to increased inputs of these compounds to the aquatic environment. Chlorinated waters can convert these chemicals into chlorinated products whose toxic effects are of primary concern. To better understand the environmental fate of sun-cream chemicals, we studied the stability of two UV-filtering compounds under varying conditions of pH, chlorine concentration, temperature, dissolved organic matter and solar irradiation.

Environmental context. Metal–carbonato complexes have been reported to contribute to metal uptake and toxicity in aquatic organisms. We show that in the presence of lead–carbonato complexes, Pb internalisation by the microalga Chlamydomonas reinhardtii is higher than that predicted on the basis of the free Pb²⁺ concentration. This effect, which was not observed for another microalga that takes up Pb more slowly, is attributed to the very high rates of Pb uptake by C. reinhardtii, which result in diffusion limitation.

Environmental context. Organic hydrophobic compounds are present in water in low concentrations, and they can be analysed by means of a preconcentration technique called solid phase microextraction. We investigate the role and role of sorbing nanoparticles on the solid phase microextraction analysis of organic compounds. Our results show that nanoparticles are capable of partitioning between water and the solid phase and aggregate at the interface leading, most probably, to substantial overestimation of the original sample concentration.

Environmental context. Mercury is a very hazardous substance for human and environmental health. Systematic long-term direct measurements in the atmosphere can provide valuable information about the effect of emission controls on the global budget of atmospheric mercury, and offer insight into source–receptor transboundary transport of mercury. A complete setup for the measurement of the four most relevant atmospheric mercury species (total gaseous mercury, gaseous oxidised mercury, particle-bound mercury, and gaseous elemental mercury) has been operating at the rural background site of Waldhof, Germany, since 2009. We present the dataset for 2009–2011, the first full-speciation time series for atmospheric mercury reported in Central Europe.

Environmental context. Throughout the world there are many places where ozone levels are elevated above internationally accepted guidelines set to protect human health. Policy makers use air quality models to formulate emission control strategies to achieve these air quality goals for ozone. There are large uncertainties in these air quality models that mask the sensitivity of the model control strategies to chemical mechanism choice.

Environmental context. Alkanes, major constituents of vehicle exhausts, are emitted to the atmosphere where they react, chiefly by gas-phase reactions with the hydroxyl radical, to form products which can also react further. In laboratory experiments, we studied the further reactions of a model first-generation alkane reaction product. Understanding alkane reaction chains is important because the toxicity, secondary aerosol formation and other properties of vehicle emissions can change as new compounds are formed.

Environmental context. Phytoplankton form the base of marine food-webs, and hence they have been proposed as the likely source of many arsenic compounds found in marine animals. Because of the difficulties associated with field experiments with phytoplankton, attempts to test this hypothesis have relied mainly on laboratory experiments. This study assesses the environmental validity of this research approach by investigating the influence of the culturing experimental protocol on the uptake, accumulation and biotransformation of arsenic by marine phytoplankton.

Environmental context. Understanding the exchange of energy, gases and particles at the ocean–atmosphere interface is critical for the development of robust predictions of, and response to, future climate change. The international Surface Ocean–Lower Atmosphere Study (SOLAS) coordinates multi-disciplinary ocean–atmosphere research projects that quantify and characterise this exchange. This article details five new SOLAS research strategies – upwellings and associated oxygen minimum zones, sea ice, marine aerosols, atmospheric nutrient supply and ship emissions – that aim to improve knowledge in these critical areas.

Environmental context. Nitrogen is an essential nutrient for marine organisms, and thus an understanding of the marine nitrogen cycle is a crucial factor in predicting the sensitivity of marine life to environmental change. Hydroxylamine is a short-lived intermediate in nitrogen transformation processes, and reliable detection of this compound in seawater can help to identify these processes within the marine nitrogen cycle.

Environmental context. Identifying the sources responsible for air pollution is crucial for reducing the effect of the pollutants on human health. The sources of the pollutants were found here by applying two mathematical models to data consisting of particle size distribution and chemical composition data. The identified sources could be used as the basis for controlling or reducing emissions of air pollution into the atmosphere.

Environmental context. The mobility and bioavailability of both contaminants and nutrients in the environment depends, to a large extent, on their diffusion. Because the majority of microorganisms in the environment are embedded in biofilms, it is essential to quantify diffusion in biofilms in order to evaluate the risk of emerging contaminants, including nanomaterials and charged solutes. This study quantifies diffusion, in a model environmental biofilm, for a number of model contaminants of variable size and charge.

Environmental context. Some long-lived organic contaminants, such as chlorinated organics, brominated flame retardants and polycyclic aromatic hydrocarbons, can undergo transport through the atmosphere to remote regions. A series of measurements of these compounds taken over almost 3 years in the air at a remote location was combined with meteorological data to try to reveal potential source areas. After adjusting several parameters to optimise the method’s ability to identify sources it was found that for most contaminants no definitive sources are revealed.

Environmental context. Contamination of groundwater by arsenic compounds used in chemical warfare research is a recently discovered environmental problem in Japan. We report evidence that the arsenic compounds originally present in the groundwater are transforming to thio-arsenic compounds of currently unknown environmental fate.

Environmental context. We report the baseline levels of dissolved nutrients, organic matter and metals in the main temperate rivers draining the three Northern Galicia rias. Because the rivers are pristine, these rias are little affected by anthropogenic inputs, and their properties reflect the lithological characteristics of the rivers’ watersheds. Useful information in the development of European and global initiatives for assessing anthropogenic inputs to estuarine, coastal and open-sea environments has been provided.

Environmental context. In 2009, at the end of the longest drought period ever recorded in Australia, a major dust storm blanketed the cities of Sydney and Brisbane for more than 24 h. The source of the dust was inner New South Wales and South Australia, where large scale open-cut mining occurs together with agricultural practices. We report results of extensive mineralogical and chemical analyses of the dust, and discuss their significance in terms of the dust origins and potential human health risks.

Environmental context. Aquatic ecosystem health may be adversely affected by dissolved organic nitrogen pollution, and accurate analytical techniques are needed to assess these effects. Our study shows that dialysis is the best sample pre-treatment technique to increase the accuracy of dissolved organic nitrogen determination. It will improve analysis and understanding of the role of dissolved organic nitrogen in the nitrogen cycle of affected aquatic ecosystems.

Environmental context. Predicting metal toxicity is an important tool for effective and efficient risk assessment and regulation of metal pollution in the environment. The present study aims to provide scientific support for the development of a predictive Ni toxicity model for aquatic plants that is particularly applicable to mining-affected natural waters. We show that the effects of pH and natural organic ligands on Ni accumulation and toxicity can be modelled, but further research is required to understand the effects of flotation ligands used in the mining industry.

Environmental context. Aromatic amines are widely used chemicals, which show enhanced toxicity and longer environmental persistence when halogenated. We investigated the chlorination of aniline in seawater and in natural aqueous solutions containing Fe³⁺ and Cl^–, under simulated sunlight irradiation. The results increase our understanding of the transformation pathway of typical nitrogen-containing aromatic contaminants in the environment.

Environmental context. Arsenic in drinking water is a global environmental concern with serious effects on human health. We have developed a cheap and effective adsorbent, based on porous hematite, for removing arsenic from water. This material could be used in adsorption columns to remove arsenic from drinking water supplies.

Environmental context. Mercury, a globally important pollutant, undergoes transformations in the environment to form methylmercury that is toxic to humans. Naturally occurring dissolved organic matter is a controller in these transformations, and we demonstrate that its strength of interaction with mercury is time dependent. These changes in complexation with dissolved organic matter are likely to affect mercury’s reactivity in aquatic systems, thereby influencing how mercury is methylated and bioaccumulated.

Environmental context. Perfluoroalkyl acids are persistent environmental contaminants that are also found in soils. We use a metabolomics approach based on nuclear magnetic resonance analyses to investigate the responses of earthworms to exposure to sub-lethal levels of two perfluoroalkyl acids. The results indicate that this metabolomics approach is able to delineate the toxic mode of action of contaminants present at sub-lethal levels.

Environmental context. Pesticides emitted to the atmosphere can undergo extensive chemical transformations through reaction with atmospheric oxidants. Understanding the atmospheric lifetime and degradation mechanism of typical pesticides is very important to health and environmental risk assessments. We investigate the degradation products, lifetimes and reaction mechanisms of two representative pesticides oxidised by ozone in order to understand the environmental behaviours of these pesticides and their analogues.

Environmental context. Perfluorinated compounds are synthetic chemicals shown to be present in the blood of humans. To study how these contaminants get into our blood requires a good understanding of their physicochemical properties. We describe an alternative way to obtain values for how perfluorinated compounds distribute between water and fatty phases (mimicking e.g. gut content and gut wall), which is essential information for modelling and understanding the environmental fate of these chemicals.

Environmental context. Exchange processes at the water–sediment interface can release metals to riverine waters, having negative effects on organisms in the water column. We investigate the geochemical processes and metal exchange between the surface sediment and the overlying water under metal contamination conditions. Results suggest that the sediment can be a significant source of metal pollution in aquatic systems, particularly during anoxic events.