detection covid-19 eaux usées

Covid-19: what could subsurface wave detection mean for the pandemic?

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The detection of SARS-CoV-2 viral infections responsible for Covid-19 allows us to monitor the evolution of the pandemic. Most methods are based on individual patient screening, with the disadvantages of cost and time. Other approaches based on the detection of SARS-CoV-2 in urban wastewater have been developed to monitor the trends in infections. Miguel Lopez-Ferber, a researcher at IMT Mines Alès, conducted a study to detect the virus in wastewater on the school’s campus. This precise, small-scale approach allows us to collect information on the probable causes of infection.

How do you detect the presence of Sars-CoV-2 in wastewater?

Miguel-Lopez-Ferber: We use the technique developed by Medema in 2020. After recovering the liquid part of the wastewater samples, we use a centrifugation technique that allows us to isolate a phase that contains the virus-sized particles. From this phase, we proceed with the extraction of the viral genomes present to perform PCR tests. PCR (polymerase chain reaction) is a technique used to amplify a genetic signal. If the PCR amplifies viral genome fragments specific to Sars-CoV-2, then the virus is present in the wastewater sample.

Does this technique tell us the concentration of the virus?

MLF: Yes. Thanks to our partnership with the PHYSE team of the HydroSciences Montpellier laboratory and the IAGE startup, we use the digital PCR technique which is a higher-resolution version of quantitative PCR. This allows us to know how many copies of the viral genome are present in the samples. With weekly sampling, we can know the trend in virus concentrations in the wastewater.

What value is there in quantifying the virus in wastewater?

MLF: This method allows for early detection of viral infections: SARS-CoV-2 is present in feces the day after infection. It is therefore possible to detect infection well before the first potential symptoms appear in individuals. This makes it possible to determine quickly whether the virus is actively circulating or not and whether there is an increase, stagnation or decrease in infections. However, at the scale at which these studies are conducted, it is impossible to know who is infected, or how many people are infected, because the viral load is variable among individuals.

How can your study on the IMT Mines Alès campus contribute to this type of approach?

MLF: To date, studies of this type have been conducted at a city level. We have reduced the cohorts to the scale of the school campus, as well as to different buildings on campus. This has allowed us to trace the sampling information from the entire school to specific points within it. Since mid-August, we have been able to observe the effects of the different events that influence the circulation of the virus, in both directions.

What kind of events are we talking about?

MLF: For example, in October, we quickly saw the effect of a party in a campus building: only 72 hours later, we observed a spike in virus circulation in the wastewater of that building, thus indicating new infections. On the contrary: when restrictive measures were put in place, such as quarantine or a second lockdown, we could see a decrease in virus circulation in the following days. This is faster than waiting to see the impact of a lockdown on infection rates 2 to 3 weeks after its implementation. This not only shows the effectiveness of the measures, but also allows us to know where the infections come from and to link them to probable causes.

What could this type of approach contribute to the management of the crisis?

MLF: This approach is less time-consuming and much less expensive than testing every person to track the epidemic. On the scale of schools or similar organizations, this would allow rapid action to be taken, for example, to quarantine certain areas before infection rates become too great. In general, this would better limit the spread and anticipate future situations, such as peak hospitalizations, up to three weeks before they occur.

By Antonin Counillon

LCA

What is life cycle analysis?

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Life cycle analysis (LCA) is increasingly common, in particular for eco-design or to obtain a label. It is used to assess the environmental footprint of a product or service by taking into account as many sources as possible. In the following interview, Miguel Lopez-Ferber, a researcher in environmental assessment at IMT Mines Alès, offers insights about the benefits and complexity of this tool.

What is life cycle analysis?

Miguel Lopez-Ferber: Life cycle analysis is a tool for considering all the impacts of a product or service over the course of its life, from design to dismantling of assemblies, and possibly recycling – we also refer to this as “cradle to grave.” It’s a multi-criteria approach that is as comprehensive as possible, taking into account a wide range of environmental impacts. This tool is crucial for analyzing performance and optimizing the design of goods and services.

Are there standards?

MLF: Yes, there are European regulations and today there are standards, in particular ISO standards 14040 and 14044. The first sets out the principles and framework of the LCA. It clearly presents the four phases of a LCA study: determining the objectives and scope of the study; the inventory phase; assessing the impact, and the interpretation phase. The ISO 14044 standard specifies the requirements and guidelines.

What is LCA used for?

MLF: The main benefit is that it allows us to compare different technologies or methods to guide decision-making. It’s a tremendous tool for companies looking to improve their products or services. For example, the LCA will immediately pinpoint the components of a product with the biggest impact. Possible substitutes for this component may then be explored, while studying the impacts these changes could lead to. And the same goes for services. Another advantage of the “life cycle” view is that it takes impact transfer into account. For example, in order to lower the impact of an oven’s power consumption, we can improve its insulation. But that will require more raw material and increase the impact of production. The LCA allows us to take these aspects into account and compare the entire lifetime of a product. The LCA is a very powerful tool for quickly detecting these impact transfers.

How is this analysis carried out?

MLF: The ISO 14040 and 14044 standards clearly set out the procedure. Once the framework of the study and objectives have been identified, the inflows and outflows associated with the product or service must be determined – this is the inventory phase. These flows must be brought back to flows from the environment. To do so, there are growing databases, with varying degrees of ease of access, containing general or specialized information. Some focus on agricultural products and their derivatives, others on plastics or electricity production. This information about flows is collected, assembled and related to the flow for a functional unit (FU) that makes it possible to make comparisons. There is also accounting software to help compile the impacts of various stages of a product or service.  

The LCA does not directly analyze the product, but its function, and it is able to compare very different technology. So we will define a FU that focuses on the service provided. Take two shoe designs, for example. Design A is of very high quality so it requires more material to be produced, but lasts twice as long as Design B. Design A may have greater production impacts, but it will be equivalent to two Design Bs over time. For the same service provided, Design A could ultimately have a lower impact.

What aspects are taken into account in the LCA?

MLF: The benefit of life cycle analysis is that it has a broad scope, and therefore takes a wide range of factors into account. This includes direct as well as indirect impacts, consumption of resources such as raw material extraction, carbon footprint, and pollution released. So there is a temporal aspect, since the entire lifetime of a good or service must be studied, a geographical aspect, since several sites are taken into consideration, and the multi-criteria aspect, meaning all the environmental compartments. 

Who conducts the LCA?

MLF: When they are able to, and have the expertise to do so, companies have them done in-house. This is increasingly common. Otherwise, they can hire a consulting firm to conduct them. In any case, if the goal is to share this information with the public, the findings must be made available so that they can be reviewed, verified and validated by outside experts.

What are the current limitations of the tool?

MLF: There is the question of territoriality. For example, power consumption will not have the same impact from one country to another. In the beginning, we used global averages for LCA. We now have continental, and even national averages, but not yet regional ones. The more specific the data, the more accurate the LCA will be.  

Read more on I’MTech: The many layers of our environmental impact

Another problem is additional or further impacts. We operate under the assumption that impacts are cumulative and linear, meaning that manufacturing two pens doubles the impacts of a single pen. But this isn’t always the case. Imagine if a factory releases a certain amount of pollutants – this may be sustainable if it is alone, but not if three other companies are also doing so. After a certain level, the environmental impact may increase.  

And we’re obviously limited by our scientific knowledge. Environmental and climate impacts are complex and the data changes in response to scientific advances. We’re also starting to take social aspects into consideration, which is extremely complex but very interesting.

By Tiphaine Claveau

Managing electronic waste: a global problem

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Responsibilities surrounding digital waste are multi-faceted. On one side, it is governments’ responsibility to establish tighter border controls to better manage the flow of waste and make sure that it is not transferred to developing countries. On the other side, electronic device manufacturers must take accountability for their position by facilitating end-of-life management of their products. And consumers must be aware of the “invisible” consequences of their uses, since they are outsourced to other countries.

To understand how waste electric and electronic equipment (WEEE) is managed, we must look to the Bâle Convention of 1989. This multilateral treaty was initially intended to manage the cross-border movement of hazardous waste, to which WEEE was later added. “The Bâle Convention resulted in regional agreements and national legislation in a great number of countries, some of whom prohibit the export or import of WEEE,” says Stéphanie Reiche de Vigan, a research professor in sustainable development law and new technologies at Mines ParisTech. “This is the case for the EU regulation on transfer of waste, which prohibits the export of WEEE to third countries.” Nevertheless, in 2015 the EFFACE European research project, devoted to combating environmental crime, estimated that approximately 2 million items of WEEE leave Europe illegally every year. How can so much electronic waste cross borders clandestinely? “A lack of international cooperation hinders efforts to detect, investigate and prosecute environmental crimes related to electronic waste trafficking,” says the researcher. And even if an international agreement on WEEE were to be introduced, it would have little impact without real determination on the part of the waste-producing countries to limit the transfer of this waste. 

This is compounded by the fact that electronic waste trafficking is caught between two government objectives: punishing environmental crimes and promoting international commerce in order to recover market share in international shipping. To increase competitiveness, the London Convention of 1965 aimed at facilitating international shipping, allowed for better movement of vessels, merchandise and passengers through ports. “The results were a simplification of customs procedures to encourage more competitive transit through ports, and distortions of competition between ports of developed countries through minimum enforcement of regulations for cross-border transfer of electronic waste, in particular controls by customs and port authorities,” says Stéphanie Reiche de Vigan. The European Union observed that companies that export and import WEEE tend to use ports where the law was less enforced, and therefore less effective.

So how can this chain of international trafficking be broken? “The International Maritime Organization must address this issue in order to encourage the sharing of best practices and harmonize control procedures,” responds the research professor. It is the responsibility of governments to tighten controls at their ports to limit these crimes. And technology could play a major role in helping them do so. “Making it compulsory to install X-ray scanners in ports and use them to visualize the contents of containers could help reduce the problem,” says Stéphanie Reiche-de Vigan. At present, only 2% of all ocean containers worldwide are physically inspected by customs authorities.

What are the responsibilities of technology companies?

The digital technology chain is divided into separate links: mining, manufacturing, marketing and recycling. The various stages in the lifetime of an electronic device are therefore isolated and disconnected from one another. As such, producers are merely encouraged to collaborate with the recycling industry. “As long as the producers of electric and electronic equipment have no obligation to limit their production, cover recycling costs or improve the recyclability of their products, electronic waste flows cannot be managed,” she says. Solving this problem would involve reconnecting the various parts of the chain through a life cycle analysis of electric and electronic equipment and redefining corporate responsibilities.

Rethinking corporate responsibility would mean putting pressure on tech giants, but developed countries seem to be incapable of doing so. Yet, it is the governments that bear the cost of sorting and recycling. So far, awareness of this issue has not been enough to implement concrete measures that are anything more than guidelines. National Digital Councils in Germany and France have established roadmaps for designing responsible digital technology. They propose areas for future regulation such as extending the lifetime of devices. But there is no easy solution since a device that lasts twice as long means half as much production for manufacturers. “Investing in a few more companies that are responsible for reconditioning devices and extending their lifetime is not enough. We’re still a long way from viable proposals for the environment and the economy,” says Fabrice Flipo, a philosopher of science at Institut Mines-Télécom Business School.

Moreover, countries are not the only ones to come up against the power of big tech companies. “At Orange, starting in 2017, we tried to put a system in place to display environmental information in order to encourage customers to buy phones with the least impact,” says Samuli Vaija, an expert responsible for issues related to product life cycle analysis at Orange. Further upstream in the chain, this measure encouraged manufacturers to incorporate environmental sustainability into their product ranges. When it was presented to the International Telecommunication Union, Orange’s plan was quickly shut down by the American opposition (Apple, Intel), who did not wish to display information about the carbon footprint on its devices.  

Still, civil society, and NGOs in particular, could build political will. The main obstacle: people living in developed countries have little or no awareness of the environmental impacts of their excessive consumption of digital tools, since they are not directly affected by them. “Too often, we forget that there are also violations of human rights behind the digital tools our Western societies rely on, from the extraction of the resources required to manufacture equipment, to the transfer of the waste they produce after just a few years. From the first link to the last, it is primarily people living in developing countries that suffer the impacts of the consumption of those in developed countries. The health impacts are not visible in Europe, since they are outsourced,” says Stéphanie Reiche-de Vigan. In rich countries, is digital technology effectively enclosed in an information bubble containing only the sum of its beneficial aspects? The importance attributed to digital technology must be balanced with its negative aspects.

As such, “it is also the responsibility of universities, engineering schools and business schools to teach students about environmental issues starting at the undergraduate level, while incorporating life cycle analysis and concern for environmental and human impacts in their programs,” says Stéphanie Reiche-de Vigan. Educating students about these issues means bringing these profiles to the companies who will develop the tools of tomorrow and the agencies meant to oversee them.

fonds industrie

Capsit and Plas’tri, the first start-ups to receive “Industry & Energy 4.0” honor loans

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After the “Digital” fund, Institut Mines-Télécom (IMT) and the Fondation Mines-Télécom launched a second fund last October called “Industry & Energy 4.0” and dedicated to the sciences of energy, materials and processes. The Capsit and Plas’tri start-ups incubated at IMT Atlantique and Mines Saint-Étienne respectively are the first to benefit from the honor loans of this new fund. 

 

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Capsit is the first compact and connected machine that allows you to go from coffee bean to capsule in a fully automated way, with a wide range of coffee available to be packed into climate neutral capsules. Capsit will receive a €60,000 honor loan. Find out more

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Plas’tri improves the efficiency of the waste treatment chain by using optics and data processing to improve sorting and create or standardize exchanges between the actors of the recycling chain. Plas’tri helps prevent the loss of material during the recycling process by proposing a device that can identify plastics and creating a platform to mutualize the transport of recyclable plastic deposits to the relevant recycler. Waste from sorting is thus limited and each item is identified and sent to the right outlet. Plas’tri was one of the 10 finalist start-ups of the Bercy IMT Innovation 2020 Prize. It will receive two honor loans for a total sum of €50,000. Find out more

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Arsenic

Arsenic contamination of water: Detection and treatment challenges

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Arsenic contamination of water, whether surface water or ground water, affects many parts of France. Such contamination may be the result of anthropogenic causes, linked to mining operations for example, or of natural causes in relation to changes in geological formations, as is the case in many countries such as India, Pakistan and Chili. In partnership with the Nuclear Materials Authority in Egypt and Guangxi University in China, a team of researchers from IMT Mines Alès has developed processes for treating contaminated water and detecting arsenic.

Arsenic may be present naturally in water used for irrigation and animal-rearing. In the majority of cases, these concentrations are low enough – less than 0.01 milligrams per liter – that they do not pose a risk to humans. Hoever, overexposure can have dramatic effects on fauna, flora and human health, by causing cancer and dermatological conditions for example.

Emblematic cases of anthropogenic contamination have been reported in relation to mining activities. In 2019, near the gold mine in Salsigne, in the south of France, children were overexposed to arsenic, probably spread through dust and the dissolution of arsenic from mine tailings. But natural phenomena, such as the infiltration of rainwater, the erosion of geological formations and soil leaching may also be the cause of contamination in many countries like India, China and Chili. 

“Unfortunately, the countries faced with this environmental and health challenge are often poor countries that don’t have access to the most advanced techniques for decontaminating water,” says Eric Guibal, a researcher at IMT Mines Alès. “In these countries, communities often rely on low-tech processes to reduce the toxicity of catchment water. Trade-offs are made between effectiveness and production and operation costs, for example through pumping and filtration using iron oxides” he explains. Along with a team of colleagues and in partnership with the Nuclear Materials Authority in Egypt and Guangxi University in China, he has contributed to the development of a number of innovative materials for the detection and treatment of arsenic in contaminated water.

Materials that “like” arsenic

“What we’re proposing is not a technique that can replace those we already have to capture arsenic, but a complementary technique in order to improve decontamination,” adds Eric Guibal. These research teams have developed a range of adsorbants, materials that can bind ions or molecules, in order to capture arsenic. Based on the use of biopolymers (extracts of seaweed and crustacean shells), they provide an alternative to those produced from petroleum resources. “Replacing petroleum-sourced materials with renewable resources is, in itself, an important challenge for the future,” he says.

Read more on I’MTech: When plants help us fight pollution

“Environmentally-friendly management has brought us to the limits of these materials; so as to avoid depleting the biotype, we limit the scope of our processes to applications such as polishing treatment and for “niches,” he explains. Combining these processes with more conventional techniques  (including precipitation, filtration, etc.) makes it possible to significantly reduce the toxicity of effluents and their discharge and improve the quality of catchment water. The targeted field of application is therefore  in line with local applications limited to areas where water quality is critical.

Various materials have been developed, for example combining the biopolymer － chitosan, a crustacean shell extract  － with metal ions － such as molybdate － which have a particular affinity for arsenic ions. When they come together, the different ions form a complex, which, once immobilized, makes it possible to recover arsenic in solution. Furthermore, the synthesis of nanocomposites in the form of hollow spheres combining molybdate with other compounds (silicate and cellulose acetate) produces nano-objects that can be used for the detection, analysis and recovery of arsenic in solutions  with low levels of contamination.

Exemple d'adsorbants microporeux à base d'algues (alginate) pour l'arsenic.
Example of microporous adsorbants made from seaweed (alginate).

Another more recently developed material is based on the functionalization of a composite, a technique used to give a material certain specific properties.  By combining seaweed with a synthetic polymer, this adsorbant material makes it possible to extract arsenic in order to decontaminate effluent or catchment water. The challenge is to release the arsenic once the material has been saturated, in order to concentrate it and recycle the adsorbant for new treatment cycles.

From the lab to the world

Another advantage of these technologies is that they offer a primary biological material that provides an alternative to the more polluting processes currently in use.  But the innovation is struggling to gain acceptance outside the laboratory, in particular since manufacturers may be reluctant to change their processes. “It’s a process that companies don’t know about and there’s a fear that there won’t be the same reproducibility ,” he adds. The variability of the resource can be a deterrent for manufacturers in terms of ensuring production and reproducible properties.

But beyond that, there is also a certain competitiveness in terms of production lines. Manufacturers already have a process that works and for which there is a market, and may not necessarily feel a need to change in order to find alternatives to petroleum-based processes. “And yet, they must be proactive and anticipate the future of petroleum-based resources,” says Eric Guibal. “There are also profitability issues involved, and if the environmental cost of the processes were taken into account, this innovation may be more appealing,”  he concludes.

Tiphaine Claveau for I’MTech

Flood, soil erosion

Agricultural sediments transported by rivers

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The QuASPEr project studied the Canche river basin in northern France to better understand the phenomenon of soil erosion and its related consequences. This knowledge aims to develop effective land management methods for municipalities without negatively affecting farmers’ work.

 

Heavy rain, dry land, sloping ground that has been tilled… and the soil erodes. This phenomenon of abrasion, in particular of agricultural soils, leads to a loss of fertile soils but also lowers water quality in rivers. For local stakeholders, this can be seen in the form of mud flows with silting of waterways and damage to infrastructures. Northern France, which is particularly  affected by this phenomenon, was the subject of the QuASPEr project (French acronym for Quantification, Analysis and Monitoring of  Erosive Processes), in partnership with the joint association Symcea, the Artois-Picardie Water Agency and two IMT schools. Claire Alary and Christine Franke, researchers at IMT Lille Douai and Mines ParisTech respectively, have studied the Canche river watershed to better understand this erosion and develop effective soil retention strategies. The team also includes Edouard Patault, a PhD student who studied the Canche river watershed for his thesis research.

“The aim of this project is to characterize, model and predict this phenomenon of erosion,” says Christine Franke. “And due to climate change, these phenomena will evolve – and not necessarily for the better. It’s important to have a clear understanding of these mechanisms to propose management plans,” adds  Claire Alary. The two researchers have been working on the topic for several years in an effort to gain a better understanding of the highest-risk areas in the region.

Soil erosion

To study the phenomenon of erosion, the first thing that is necessary is a good understanding of the area. “It’s not necessarily a phenomenon of heavy rain that causes this erosion,” says Christine Franke. A number of parameters must be taken into account and this phenomenon is highly variable. The first rains of the season can often trigger erosion since the soil is dry and erodes more easily. The duration and intensity of the rain are significant factors but the type of soil is also very important: soil composition, vegetation cover, the degree of slope of the land etc.

This soil erosion is a recurring problem and it is difficult to identify the causes. A watershed like that of the Canache river is divided into a number of small basins, and the researchers’ goal is to find out the precise area from which the eroded particles come. To do so, it is critical to have a precise understanding of the system at each instant. Installing a monitoring station allows for such an understanding, but very locally, and stations are too expensive to be placed throughout the watershed. They must therefore be combined with other techniques to get a clear view of the system and its variability over time. The researchers studied this through the magnetic fingerprint of the sediments, a technique they adapted to this erosion phenomenon.

“We installed a trap in the river to collect these sediments suspended in the water and then sent them to the laboratory to be studied,” explains  Christine Franke. The method is relatively easy to implement and accessible for the municipalities. Moreover, it is a non-destructive method, meaning that researchers can carry out several analyses on a single sample. In practice, what they study is the mineralogy of iron in the samples. “The iron particles present in agricultural soils are not the same as those found naturally in the river,” she adds.

They have a distinctive signature that allows researchers to differentiate between particles from rivers and from fields. “The eroded particles from the field will keep this signature for a fairly long time once they’re in the river,” explains the researcher. This erosion phenomenon is also characterized by a procession of geochemical elements for each material arriving in the river. “We know the chemical characteristics of the sources of the material, so we’re able to trace this signal back to determine the contributions of the sources from which the sediments originate,” says Claire Alary.

Photograph of a gully in the Canche river watershed.

Photograph of a gully in the Canche river watershed

 

Land management

This project seeks to better understand how the system functions overall in order to identify the most problematic areas and propose adapted solutions. Certain features have been installed to limit erosion, such as hedges and fascines. Fascines are bundles of branches arranged in a line to retain soil and combat erosion. While these measures are effective, they are not enough to prevent damage. By gaining a better understanding of erosion and of the watershed, complementary retention methods could be found to enhance the effectiveness of current methods.

The possibilities for this project continue today with the launch of the GeSS (Managing Sediments at the Source) project run by the Ecosed Digital 4.0 chair, led by Nor-Edine Abriak, a researcher at IMT Lille Douai, along with Fondation Mines Télécom. The challenge is to tackle this phenomenon of erosion at the source and in particular to work on reducing the transfer of sediments for better management of this phenomenon in the various regions.

 

Tiphaine Claveau

planetary boundaries, urgence climatique, planet's limits

Covid-19 Epidemic: an early warning signal that we’ve reached the planet’s limits?

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Natacha Gondran, Mines Saint-Étienne – Institut Mines-Télécom and Aurélien Boutaud, Mines Saint-Étienne – Institut Mines-Télécom

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This article was published for the Fête de la Science (Science Festival, held from 2 to 12 October 2020 in mainland France and from 6 to 16 November in Corsica, overseas departments and internationally), in which The Conversation France is a partner. The theme for this year’s festival is “Planète Nature”. Read about all the events in your region at Fetedelascience.fr.

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[dropcap]W[/dropcap]hen an athlete gets too close to the limits of his body, it often reacts with an injury that forces him to rest. What athlete who has pushed himself past his limits has not been reined in by a strain, tendinitis, broken bone or other pain that has forced him to take it easy?

In ecology, there is also evidence that ecosystems send signals when they are reaching such high levels of deterioration that they cannot perform the regulatory functions that allow them to maintain their equilibrium. These are called early warning signals.

Several authors have made the connection between the Covid-19 epidemic and the decline of biodiversity, urging us to see this epidemic as an early warning signal. Evidence of a link between the current emerging zoonoses and the decline of biodiversity has existed for a number of years and that of a link between infectious diseases and climate change is emerging.

These early warning signals serve as a reminder that the planet’s capacity to absorb the pollution and deterioration to which it is subjected by humanity is not unlimited. And, as is the case for an athlete, there are dangers in getting too close to these limits.

Planetary boundaries that must not be transgressed

For over ten years, scientists from a wide range of disciplines and institutions have been working together to define a global framework for a Safe Operating Space (SOS), characterized by physical limits that humanity must respect, at the risk of seeing conditions for life on Earth become much less hospitable to human life. This framework has since been added to and updated through several publications.

These authors highlight the holistic dimension of the “Earth system”. For instance, the alteration  of land use and water cycles makes systems more sensitive to climate change. Changes in the three major global regulating systems have been well-documented – ozone layer degradation, climate change and ocean acidification.

Other cycles, which are slower and less visible, regulate the production of biomass and biodiversity, thereby contributing to the resilience of ecological systems – the biogeochemical cycles of nitrogen and phosphorous, the freshwater cycle, land use changes and the genetic and functional  integrity of the biosphere. Lastly, two phenomena present boundaries that have not yet been quantified by the scientific community: air pollution from aerosols and the introduction of novel entities (chemical or biological, for example).

These biophysical sub-systems react in a nonlinear, sometimes abrupt way, and are particularly sensitive when certain thresholds are approached. The consequences of crossing these thresholds may be irreversible and, in certain cases, could lead to huge environmental changes..

Several planetary boundaries have already been transgressed, others are on the brink

According to Steffen et al. (2015), planetary boundaries have already been overstepped in the areas of climate change, biodiversity loss, the biogeochemical cycles of nitrogen and phosphorous, and land use changes. And we are getting dangerously close to the boundaries for ocean acidification. As for the freshwater cycle, although W. Steffen et al. consider that the boundary has not yet been transgressed on the global level, the French Ministry for the Ecological and Inclusive Transition has reported that the threshold has already been crossed in France.

These transgressions cannot continue indefinitely without threatening the equilibrium of the Earth system – especially since these processes are closely interconnected.  For example, overstepping the boundaries of ocean acidification as well as those of the nitrogen and phosphorous cycles will ultimately limit the oceans’ ability to absorb atmospheric carbon dioxide. Likewise, the loss of natural land cover and deforestation reduce forests’ ability to sequester carbon and thereby limit climate change. But they also reduce local systems’ resilience to global changes.

Representation of the nine planetary boundaries (Steffen et al., 2015):

Steffen, W. et al. “A safe operating space for humanity”. Nature 461, pp. 472–475

 

Taking quick action to avoid the risk of drastic changes to biophysical conditions

The biological resources we depend on are undergoing rapid and unpredictable transformations within just a few human generations. These transformations may lead to the collapse of ecosystems,  food shortages and health crises that could be much worse than the one we are currently facing.  The main factors underlying these planetary impacts have been clearly identified: the increase in resource consumption, the transformation and fragmentation of natural habitats, and energy consumption.

It has also been widely established that the richest countries are primarily responsible for the ecological pressures that have led us to reach the planetary boundaries, while the poorer countries of the Global South, are primarily victims of the consequences of these degradations.

Considering the epidemic we are currently experiencing as an early warning signal should prompt us to take quick action to avoid transgressing planetary boundaries. The crisis we are facing has shown that strong policy decisions can be made in order to respect a limit – for example, the number of beds available to treat the sick. Will we be able to do as much when it comes to planetary boundaries?

The 150 citizens of the Citizens’ Convention for Climate have proposed that we “change our law so that the judicial system can take account of planetary boundaries. […] The definition of planetary boundaries can be used to establish a framework for quantifying the climate impact of human activities.” This is an ambitious goal, and it is more necessary than ever”.

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Aurélien Boutaud and Natacha Gondran are the authors of Les limites planétaires (Planetary Boundaries) published in May of 2020 by La Découverte.

Natacha Gondran is a research professor in environmental  assessment at Mines Saint-Étienne – Institut Mines-Télécom and Aurélien Boutaud, holds a PhD in environmental science and engineering from Mines Saint-Étienne – Institut Mines-Télécom.

This article has been republished from The Conversation under a Creative Commons license. Read original article (in French).

environmental impact

20 terms for understanding the environmental impact of digital technology

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While digital technology plays an essential role in our daily lives, it also a big consumer of resources. To explore the compatibility between the digital and environmental transitions, Institut Mines-Télécom and Fondation Mines-Télécom are publishing their 12th annual brochure entitled Numérique : Enjeux industriels et impératifs écologiques (Digital Technology: Industrial Challenges and Environmental Imperatives). This glossary of 20 terms taken from the brochure provides an overview of some important notions for understanding the environmental impact of digital technology.  

 

  1. CSR: Corporate Social Responsibility — A voluntary process whereby companies take social and environmental concerns into account in their business activities and relationships with partners.
  2. Data centers — Infrastructure bringing together the equipment required to operate an information system, such as equipment for data storage and processing.
  3. Eco-design — A way to design products or services by limiting their environmental impact as much as possible, and using as few non-renewable resources as possible.
  4. Eco-modulation — Principle of a financial bonus/penalty applied to companies based on their compliance with good environmental practices. Primarily used in the waste collection and management sector to reward companies that are concerned about the recyclability of their products.
  5. Energy mix — All energy sources used in a geographic area, combining renewable and non-renewable sources.
  6. Environmental responsibility — Behavior of a person, group or company who seeks to act in accordance with sustainable development principles.
  7. Green IT — IT practices that help reduce the environmental footprint of an organization’s operations.
  8. LCA: Lifecycle Analysis — Tool used to assess the overall environmental impacts of a product or service, throughout its phases of existence, by taking into consideration a maximum of incoming and outgoing flows of resources and energy over this period.
  9. Mine tailings — The part of the rock that is left over during mining operations since it does not have enough of the target material to be used by industry.
  10. Mining code — Legal code regulating the exploration and exploitation of mineral resources in France, dated from 2011, based on the fundamental principles of Napoleonic law of 1810.
  11. Paris Climate Agreement — International climate agreement established in 2015 following negotiations held during the Paris Climate Conference (COP21). Among other things, it sets the objective to limit global warming to 2 degrees by 2100, in comparison to preindustrial levels.
  12. PUE: Power Usage Effectiveness — Ratio between the total energy consumed by a data center to the total energy consumed by its servers alone.
  13. Rare earths— Group of 17 metals, many of which have unique properties that make them widely used in the digital sector.
  14. Rebound effect — Increased use following improvements in environmental performance (reduced energy consumption or use of resources).
  15. Responsible innovation — Way of thinking about innovation with the purpose of addressing environmental or social challenges, while considering the way the innovation itself is sought or created.
  16. RFID: Radio-frequency identification — Very short distance communication method based on micro-antennas in the form of tags.
  17. Salt flat — High salt desert, sometimes submerged in a thin layer of water, containing lithium which is highly sought after to make batteries for electronic equipment.
  18. Virtualization — The act of creating a virtual an IT action, usually through a service provider, in order to save on IT equipment costs.
  19. WEEE: Waste Electrical and Electronic Equipment — All waste from products operated using electrical current and therefore containing electric or electronic components.
  20. 5G Networks — 5th generation mobile networks, following 4G, will make it possible to improve mobile data speed and present new possibilities for using mobile networks in new sectors.
silent cities project

Locked-down world, silent cities

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Last spring, France decided to impose a lockdown to respond to the health crisis. Our cities came to a standstill and cars disappeared from the streets, allowing residents to rediscover quieter sounds like birdsong. A team of researchers decided to take advantage of this calm that suddenly settled over our lives to better understand the impacts of sound pollution, and created the Silent Cities project.

 

When the lockdown was announced and France was getting ready to come to a halt, a team of researchers launched a collaborative, interdisciplinary project: Silent Cities. The team includes Samuel Challéat,¹ Nicolas Farrugia,² Jérémy Froidevaux³ and Amandine Gasc,4 researchers in environmental geography, artificial intelligence, biology and ecology, respectively. The aim of their project is to record the sounds heard in cities around the world to study the impacts that lockdown and social distancing measures may have on noise pollution. The project also seeks to assess the effects of the variation of our activities on other animal species as our lives gradually return to normal.

Listening to cities

“We had to develop a standard protocol to obtain high-quality recordings for the analyses, but they also had to be light and easy to implement during the lockdown,” explains Nicolas Farrugia, a researcher in machine learning and deep learning at IMT Atlantique. Due to the lockdown, it was not possible to go directly into the field to carry out these acoustic surveys. A collaborative system was set up to allow  a large number of participants around the world to take part in the project by making recordings from their homes. The four researchers provided a collaborative platform so that the participants could then upload their recordings.

Interactive map of the Silent Cities project participants around the world.

The researchers analyzed and compared recordings at different sites using what they call ecoacoustic indices. These are mathematical values. The higher they are, the more they show the diversity and complexity of sounds in an acoustic survey. “Still using an open-access approach, we used a code base  to develop an algorithm that would automatically calculate these ecoacoustic indices in order to catalogue our recordings” explains Nicolas Farrugia.

“The goal is to run audio-tagging algorithms to automatically recognize and tag different sounds heard in a recording,” he adds. This makes it possible to obtain a fairly accurate identification of sound sources, indicating, for example, the presence of a car, a raven’s caw or a discussion between several people in a sound survey.

This type of algorithm based on deep neural networks has become increasingly popular in recent years. For acoustic ecologists, they provide recognition that is relatively accurate, and more importantly, multi-targeted: the algorithm is able to seek many different sounds at the same time to tag all the acoustic surveys. “We can also use them as a filter if we want to find all the recordings where we hear a raven. That could be useful for measuring the appearance of a species, by visualizing the time, date or location,” says Nicolas Farrugia.

The contribution of artificial intelligence is also a help to estimate the frequency of different categories of sounds  — for automobile traffic for example — and visualize the increase or decrease. During the lockdown, the researchers clearly observed a drop in automobile traffic and now expect to see it go back up as our lives are gradually returning to normal. What they are interested in is being able to visualize how this may disturb the behavior of other animal species.

What changes?

“Some studies have shown that in urban environments, birds can change the frequency or time of day at which they communicate, due to ambient noise,” says Nicolas Farrugia. The sound of human activities, saturating the urban environment can, for example, make it difficult for certain species to reproduce. “That said, it’s hard to talk about causality since, in normal times, we can’t listen to urban ecosystems without the contribution of human activities.”  It is therefore usually difficult for eco-acoustics researchers to fully understand the biodiversity of our cities.

In this respect, the Silent Cities project provides an opportunity to directly study the variation in human activity and how it impacts ecosystems. Some of the measures put in place to respond to the health crisis could subsequently be promoted for ecological reasons. One such example is cycling, which is now being encouraged  through financial assistance to repair old bicycles and creating new cycle paths. Another example is initiatives to establish staggered working hours, which would also limit the associated noise pollution. One of the possible prospects of the project is to inform discussions about how urban environments should be organized.

” Samuel Challéat, the researcher who initiated this project, works on light pollution and what we can be done to limit artificial light,” he adds. For example — like “green and blue belts,” which seek to promote the preservation of so-called “ordinary” biodiversity including in urban environments — he is currently working on an emerging planning tool, the “black belt,” which aims to restore nocturnal ecological continuity which has been harmed by artificial light. Since we know that the sounds created by human activities disturb certain ecological processes, this reasoning on ecological continuity could be transferred to the field of eco-acoustics, where the challenge would be to work to maintain or restore spaces free from any noise pollution. The data and results of the Silent Cities project could help provide insights in this area.

By Tiphaine Claveau

 

¹Samuel Challéat, Environmental Geography, University of Toulouse 2, CNRS, GEODE (guest researcher), Toulouse, France

²Nicolas Farrugia, Machine Learning & Deep Learning, IMT Atlantique, CNRS, Lab-STICC, Brest, France

³Jérémy Froidevaux, Conservation Biology, University of Bristol, School of Biological Sciences, Bristol, UK

4Amandine Gasc, Conservation Ecology, Aix Marseille University, Avignon University, CNRS, IRD, IMBE, Marseille, France

 

retardateurs de flamme

Do flame-retardant pillows pollute our homes?

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Chemical additives called flame retardants prevent our furniture from burning too quickly in the event of a fire. But do these molecules pollute the air inside our homes and offices? To answer this question, an ANSES-ADEME research project was launched in 2019 and IMT Mines Alès is taking part in it. In a testing laboratory that reproduces the conditions of a room at full scale, the researchers are establishing a new methodology for studying pollutants found in furniture.

 

Since we are all at home under lockdown orders, the issue of indoor air pollution has become more important. We know that in general, cleaning products and burning candles pollute our homes, and that it is important to ventilate our living spaces, in order to renew the air. But our furniture and other decorative items also contain substances that can impact indoor air quality and health.

Certain additives are added to upholstered furniture – such as foams used in seats and bedding – in order to limit the spread of flames in the event of a fire. Until the 2000s, brominated compounds, PBDEs (PolyBromoDiphenyl Ethers), were used for this purpose. As they were considered to be too toxic, PBDEs were prohibited in Europe and in many other countries in 2005 and were replaced by new substances such as organophosphorus compounds.

In order to assess the risks of exposure to these new substances, the French Agency for Food, Environmental, and Occupational Health and Safety (ANSES) and the French Environmental and Energy Management Agency (ADEME) have teamed up to fund a research project in which Valérie Desauziers and Hervé Plaisance, researchers who study indoor air quality at IMT Mines Alès, are taking part. Their aim is to evaluate the transfer capacity of these organophosphorus compounds in upholstered furniture to the air.

Living room or laboratory?

The researchers are working in a real environment in order to study different ways molecules can  travel. Seats containing flame retardants, made especially for the project, have been installed in two identical unoccupied offices to reproduce an indoor environment.  In one of the offices, the seats were first subjected to accelerated aging to evaluate the long-term impact of the emission of these materials. Apart from that, everything is similar: “The temperature, humidity level and air change rate are measured throughout the test,” says Valérie Desauziers. “We’re never in an entirely enclosed, airtight environment, we have to take that into consideration in our study so that it is as similar as possible to real exposure conditions.”

The organophosphorus compounds studied are distinctive in that they are semi-volatile substances.  “The more the volatility of the compounds decreases, the more we experience analytical problems, especially sampling,” explains Hervé Plaisance. These semi-volatile compounds are spread out between the air and interior surfaces: “it’s a rather complex distribution in the indoor environment between  gaseous and particulate fractions,” he adds. To assess the behavior of these pollutants inside a room as well as the risk of exposure, it is not enough to study only their concentration in the air.

To take these properties into account, the researchers have developed an original sampling methodology. They use a small glass cylindrical cell that is simply placed on the material to be characterized. A fiber made from an absorbent material is then inserted into this cell in order to trap the molecules emitted by the material. The fiber is then analyzed in the laboratory. “This technique allows us to determine the concentration of pollutants at the interface between the material and the air, and therefore characterize the materials that are sources of pollutants as well as the deposition of pollutants on the other surfaces inside a room,” says Valérie Desauziers.

Photograph of the cell used to carry out measurements of the transfer of molecules to the air.

Over the course of the nine-month on-site study, measurements of the concentrations of flame retardants are carried out periodically in the air, on the surface of the emitting material and on the floor, walls, ceiling and bay window in an effort to understand the behavior of these semi-volatile molecules.

Choosing the least polluting materials

The sampling and analysis methodology developed is useful for identifying sources of pollutants in an indoor environment. “It can also help us choose and develop materials that emit fewer pollutants,” adds the researcher. “By measuring the concentrations in the air and on the surfaces, we can carry out a mass balance, which will allow us to better understand the transfer dynamics of these molecules and their distribution in indoor environments,” adds Hervé Plaisance. Ultimately, the goal is to be able to model these phenomena, incorporating parameters such as air change, the deposition of molecules on surfaces, and source emission.

“As far as the current project is concerned, it’s too early to give precise results about the quantities of flame retardants emitted by the upholstered furniture studied, but we have already shown that transfer to the air occurs,” say the researchers. This means that there is a risk of exposure through inhalation, but the risk has not yet been assessed. For these type of molecules, this field study in real conditions is the first of its kind. This research will then have to be continued, drawing on expertise in the field of health hazards in order to assess the health impact of these emerging pollutants.

 

Tiphaine Claveau for I’MTech