Nano-sized particles of plastic can be more damaging to marine species than larger sized microplastics, a new study shows. Lab tests revealed that nanoplastics can damage cell membranes in tiny marine creatures called rotifers (Rotifera), disrupting their natural defences against toxicants. The researchers found that rotifers that had been exposed to nanoparticles of polystyrene were significantly more susceptible to the lethal effects of persistent organic pollutants (POPs).

Soil biodiversity, soil quality, and soil health are integral to protecting the natural environment. Soils are crucial to food production and human well-being, as highlighted by the UN Sustainable Development Goals (SDGs). The abundance of soil biota is of great importance for the provision of associated ecosystem services (ES) and fundamental driver of self-regulation in soil. This study explores how the presence, or absence, of earthworms affects aspects of crop health and productivity, focusing on their shielding of winter wheat from the toxic plant fungi Fusarium.

Microplastics, polymer-based particles of less than five millimetres in size, have become an archetypal sign of anthropogenic waste and environmental pollution. This German study explores how microplastics in soil affect plants, screening the potential effects of six different microplastics on the soil environment, plant traits and function using a terrestrial plant-soil model based on the spring onion (Allium fistulosum). The researchers find that plants react strongly to microplastic exposure, with significant changes observed in the physical parameters of soil, plant root and leaf traits and plant biomass.

Rare earth elements (REE) are used to make many low-carbon technologies, including electric vehicles and wind turbines. Mining and processing of REE, which mostly takes place in China, has a reputation for causing environmental damage. A new study presents a method for evaluating the environmental impacts of REE production based on life-cycle assessment (LCA: a way of determining a product's overall impact during some or all of its journey from extraction to end-of-life). The researchers applied the method to a prospective REE mine in Malawi, south-east Africa, to reveal the most environmentally impactful stages of production, and the greenest source of energy.

Of all the MATLAB or MathWorks toolbox functions that have been mentioned in this blog since 2006, imshow and imread have appeared the most. As in last week's post, they often appear together, right at the beginning: ... read more >>

In my first year of writing this blog (2006!), I showed how to overlay a color onto an image based on a mask. This was the example I gave back then:... read more >>

The 3rd edition of Digital Image Processing Using MATLAB (DIPUM3E) has just been published, at long last. The new edition includes extensive new coverage of image transforms, spectral color models, geometric transformations, clustering, superpixels, graph cuts, active contours, maximally-stable extremal regions, SURF and similar feature detection, and deep learning networks.... read more >>

I like to think of geometric transformations of images (stretching, shrinking, rotating, etc.) by starting with the geometric transformations of points. You could think of a geometric point transformation as just moving a point from one location to another, like this:... read more >>

Baylis, Françoise, 1961- author

Methane gas emissions could have a larger warming effect on climate than has been previously thought. A recent study has found that the interactions between greenhouse gas (GHG) emissions and aerosols in the atmosphere can change the impact of various emissions, and that mitigation policies should take these effects into account.

If the effects of air pollution on climate change are included in air quality strategies, efficiency gains of €2.5 billion can be achieved in the EU, according to recent research.

New research suggests potential benefits in integrating air quality and climate change policy. It predicts that accounting for the climate impact of certain air pollutants in the EU, USA and China could complement policies designed to reduce the air quality impacts of these pollutants.

A new study has assessed the potential of several “fast-action” climate change mitigation strategies. Key options are reducing use of hydrofluorocarbons (HFCs), reducing emissions of black carbon and ozone-forming pollutants, and sequestering carbon through afforestation and biochar production.

A new study suggests that widespread adoption of hydrogen fuel could have major benefits for tackling climate change and air pollution. The researchers modelled the impacts of replacing petrol with hydrogen as a fuel for cars and claim their methods, which employ a new modelling tool, could be useful in planning and policymaking.

20 years of policies in Europe to reduce emissions that contribute to the formation of ozone have successfully reduced short-term peak ozone levels, according to a new study conducted in central England. However, tougher targets are needed to further reduce average annual levels.

The policy implications of agricultural losses caused by high concentrations of ground level ozone have been highlighted by a recent study. The study modelled ozone impacts on 14 of the most important crops grown in the Greater Thessaloniki area of Greece. The results provide information about differences in scale of losses and economic impacts across the region which may be useful in designing agricultural subsidy schemes.

Climate change is likely to significantly affect future air quality over Europe. According to a recent European study, climate change alone is likely to significantly increase ozone pollution in Europe and by as much as 50 µg.m-3 (micrograms per cubic metre) over central France in July by the year 2100, compared with 1990 levels.

A recent study has compared the impact of future power generated from large, central stations with power generated from smaller distributed generators (DG) in California on air quality. It concluded that although DG produces more emissions, its impact on air quality is likely to be smaller than central power stations due to complex interactions between air chemistry and transport.

A study by Swedish scientists provides new insights into how climate change could affect future ozone concentrations in European countries. The findings of this study suggest that average ozone concentrations will increase more in Southern Europe than in more Northern and mountainous regions under the influence of climate change in the 21st century.

Combining policies that tackle local air pollution and global climate change will deliver enhanced benefits for climate change mitigation, according to researchers. Medium-term efforts to control air pollution will provide additional benefits to long-term strategies that aim to curb climate change.

A study in the Czech Republic has found a link between exposure to certain air pollutants and an increase in DNA damage for people exposed to high levels of the pollution. They found that breathing small quantities of a polycyclic aromatic hydrocarbon (PAH), called benzo[a]pyrene (B[a]P), caused an increase in the number of certain ‘biomarkers’ in DNA associated with a higher risk of diseases, including cancer.

Using hydrogen as an energy carrier can help reduce air pollution and greenhouse gas (GHG) emissions associated with fossil fuels, according to recent research. However, if used on a large-scale, it is important that hydrogen does not leak significantly into the atmosphere as it might have some negative environmental effects, such as increasing the lifetime of methane, increasing climate effects and causing some depletion of the ozone layer.

A new report suggests that underground carbon storage projects in Europe could lead to positive and negative effects on air pollution, depending on the pollutant in question. Carbon capture and storage (CCS) is considered in European legislation as a ‘bridging technology’ – a medium-term solution to climate change. Although the overall air quality impact of CCS is expected to be positive, the legislation notes that the technology should not be seen as a replacement for commitments to developing a greener and more energy-efficient economy.

Implementation of technology to clean the flue gases of coal-fired power plants has significantly reduced sulphur and fine particle emissions that cause environmental damage. However, recent research suggests that plants applying this technology would emit more ultrafine particles (1-10 nanometer (nm) diameter) that affect the formation of clouds, with the unintended consequence of changing the amount and intensity of rainfall downwind of fossil fuel power installations.

The Earth is now absorbing more energy from the Sun than it is radiating into space. A recent analysis indicates that most models of this energy imbalance underestimate the impacts of human-made aerosols and overestimate time lags in response to the climate. As such, the energy imbalance and future impacts on climate may be greater than predicted.

City dwellers who grow their own fruit and vegetables may be consuming high levels of pollutants. In a recent study, researchers found that vegetables grown on plots in Berlin, Germany, often contained higher concentrations of some heavy metals than shop-bought vegetables, with those grown close to busy roads containing the greatest quantities.

More Europeans are driving diesel cars, with important implications for vehicle emissions. A new study suggests that diesel cars may emit nitrogen oxides (NOx) at levels far higher than emissions standards, even when considering the newest generation of diesel cars. Part of the problem is that tests of vehicle emissions in the laboratory do not accurately reflect on-road emissions.

Low emission zones (LEZs), which restrict access for high emission vehicles, have proven to be a successful way to improve air quality in line with EU regulations. An analysis of London’s LEZ has revealed discernible reductions in air pollution levels five years after implementation.

Climate change affects air pollution at a regional and local scale. A recent study has reassessed the latest findings and suggests that climate change will increase ozone concentrations by about 3 parts per billion (ppb) in central and western Europe in the year 2050 if emissions from human activities remain at present-day levels. However, if emissions increase, ozone concentrations could increase by 16 ppb for much of Europe.

The most up-to-date knowledge and data must be used to assess policy objectives, new research confirms. Studying air pollution environmental quality targets set by the National Emission Ceilings (NEC) Directive1, a new study has shown that if 2001 data are used to assess progress, most such targets appear to have been met. However, more recent and accurate current data show that this may not be the case.

Globally co-ordinated climate change policy to limit warming to 2°C could provide additional health, ecological and economic benefits. Using established methods, researchers estimated that the implementation of climate policy would also reduce global expenditures on air pollution control in 2050 by €250 billion.

The EU's Nitrates Directive has led to significant decreases in nitrogen pollution in Europe, a new study suggests. Modelled scenarios with and without implementation of the Directive showed that it had resulted in a 16% reduction of nitrate leaching by 2008. These improvements could be further increased as implementation becomes stricter, the researchers conclude.

Emissions of non-methane volatile organic compounds (NMVOCs) can have damaging effects on human health. New research has now revealed that only three substances out of a large number of NMVOCs are responsible for almost all damaging effects on human health. Air pollution policies should be designed to target these substances specifically, rather than overall NMVOC emissions, the researchers recommend.

Better hydrogen production could be on the horizon thanks to a cheap new way of making a key component of electrolysers with a 3D printer, a new study suggests. This achievement could speed-up the development of electrolysis, a method of extracting hydrogen from water.

European emissions of sulphur and nitrogen pollution have fallen greatly in recent decades, a new report shows. However, even at present levels they harm sensitive ecosystems, and will continue do so for some years to come.

Levels of particulate matter (PM) in the atmosphere are linked to ammonia emissions. However, reducing ammonia emissions only as far as targets set out by the Gothenburg Protocol will not necessarily ensure compliance with EU PM limits, according to a new study. Greater reductions in ammonia emissions would reduce the number of days when PM limit values are exceeded, the researchers found.

Greater amounts of air pollutants emitted in East Asia will move around the globe under climate change, a recent study predicts. Changes to wind speeds and air pressure will mean that movement of pollution from this region is enhanced under a changing climate. These results highlight the need for globally coordinated efforts to tackle air pollution and climate change.

Effective greenhouse gas (GHG) mitigation measures to stabilise global temperature change to no more than 2°C above pre-industrial temperatures would also substantially reduce air pollutant emissions, recent research predicts. A variety of mitigation options are available, including switching from fossil fuels to renewable sources of energy. To achieve the necessary GHG emission reductions, one key option is to impose carbon taxes. However, these would need to be high to help achieve this target, according to the study’s authors.

Emissions from well-regulated household waste incinerators do not reduce the quality of vegetables and milk produced nearby, a Dutch study suggests. Researchers found that levels of certain contaminants were similar whether vegetables and milk came from the area surrounding three incinerators, or from elsewhere in the Netherlands. They say biomonitoring programmes could offer a way to increase the understanding of the real impacts of waste incineration and to improve communication between waste management companies and local communities.

Deposition of heavy metals and nitrogen is falling across Europe, a new study suggests. The researchers used the levels of these pollutants in mosses as indicators of how deposition has changed from 1990 to 2010. These reductions are likely to be the result of effective air pollution policies, they say.

Congestion charges are an effective means of reducing road traffic, but are often strongly opposed by the public. This study combined quantitative and qualitative methods to explore attitudes towards congestion charging in Spain, finding that opposition is reduced when revenues are spent on environmental improvements.

Ships that reduce their speed use less fuel, which lowers costs for shipping companies. The slow steaming practice also cuts nitrogen oxides (NOx) emissions. A study found that ships travelling on four European routes lowered their NOx emissions by 12% during the economic crisis of 2008/2009. Shipping continues to be a major way of transporting goods, however, and as the global economy recovers the researchers and civil society call for additional measures to reduce NOx emissions from shipping and improve air quality in Europe.

The health risks associated with climate-induced changes to indoor environments are explored in a new study. UK-based researchers synthesised findings of how climate change — and mitigation and adaptation measures — might affect the inside of buildings, through overheating, air quality, allergies and infections, flood risk and other exposure risks.

Underground trains are among the most widely used public transport systems in cities worldwide. A study investigating the chemical composition and source of particles in Barcelona subway stations found that a new station design, with sliding doors that separate the platform from the tunnel and good ventilation, reduced the concentration of fine particulate matter (PM2.5) by over 50% compared with older station designs.

Dangerously high air pollution in the vicinity of shipbreaking yards has been detected by a recent study, where the concentrations of toxic chemicals in the air were found to be above carcinogenic risk limits (as set by the World Health Organisation). The research, carried out in Chittagong, Bangladesh, noted that shipbreaking activities and the subsequent processing and treatment of materials – particularly the burning of waste — result in emissions of persistent organic pollutants (POPs).

Pollutants emitted by human activities have caused declines in air quality and drastic changes to climate. Despite being inextricably linked, these two major environmental issues tend to be viewed separately by policy. However, in certain instances, considering these issues together could lead to strategies that benefit both, according to a newly published review.

Oxygen decline is occurring in many of the world’s oceans and has important consequences for marine ecosystems, but the causes are not fully understood. Aerosol pollutants may be partly responsible, according to a new study which modelled the effects of atmospheric pollution over the Pacific Ocean. The findings suggest that air pollution can exacerbate climate impacts on the ocean, even when the source is far away.

Nitrous oxide (N₂O) is a potent greenhouse gas and atmospheric pollutant. A new study proposes tackling both problems by removing N₂O from the atmosphere using a combination of two innovative technologies — photocatalytic breakdown of the N₂O to nitrogen and oxygen, and this within a solar chimney power plant that generates renewable electricity. Although some way off from commercial development, the researchers say this approach is feasible, and they outline how these two technologies can be integrated to reduce the climate impact and polluting effects of N₂O emissions.

Nitrification inhibitors are thought to mitigate climate change by reducing emissions of nitrous oxide — a potent greenhouse gas — from land. However, they may not be as effective as once thought, a new study suggests. The researchers found that, while inhibitors decrease emissions of nitrous oxide, they can increase emissions of ammonia — which is later converted to nitrous oxide. They recommend these effects are considered when evaluating inhibitors as a mitigation technology.

Researchers have shown that emissions from vehicles can react with emissions from urban trees and other plants, resulting in a decrease in air quality in cities in summer; this reduces the otherwise positive impacts of urban vegetation. The study, conducted in Berlin, showed that during a July heatwave, 20% of ozone concentrations were due to emissions of volatile organic compounds (VOCs) from vegetation interacting with other pollutants. To reduce this effect, lowering emissions of these other pollutants is crucial.