It’s possible that I shall make an ass of myself. But in that case one can always get out of it with a little dialectic. I have, of course, so worded my proposition as to be right either way (K.Marx, Letter to F.Engels on the Indian Mutiny)
Friday, March 28, 2025
Human urine, a valuable resource as fertilizer for sustainable urban agriculture
The reuse of human urine would allow for the production of sustainable fertilizers for urban agriculture, with significant environmental benefits. This is the conclusion of a study conducted by the Institute of Environmental Science and Technology at the Universitat Autònoma de Barcelona (ICTA-UAB), which evaluates the environmental impact of nitrogen recovery from the yellow waters of buildings. In addition to promoting sustainable agriculture, it would reduce CO2 emissions and water consumption.
The global demand for fertilizers in agriculture is growing every day, making it necessary to reduce dependence on non-renewable sources. According to the Food and Agriculture Organization (FAO), the global demand for nitrogen as a fertilizer grows annually by 1%, which amounts to an increase of 1.074 million tons each year.
The production of these fertilizers relies heavily on non-renewable energy sources such as natural gas, oil, and coal, representing significant energy consumption and CO2 emissions.
This new study, led by the Sostenipra group of ICTA-UAB in collaboration with the GENOCOV group of the Department of Chemical, Biological, and Environmental Engineering, presents human urine nutrient recovery as a solution to transforming urban agriculture. The article, published in the scientific journal Resources, Conservation and Recycling, explains that the use of urine allows exploiting local resources and minimizes the use of external inputs, contributing to the sustainability of the agricultural process. Furthermore, it reduces dependence on limited resources and supports a more environmentally responsible cycle.
In this context, human urine or "yellow water" is a rich source of nutrients, particularly nitrogen, essential for agricultural production. In addition to its benefits as a fertilizer, it helps reduce greenhouse gas emissions and pollution from water sources such as rivers and aquifers.
To assess its feasibility, researchers tested the process in the bioclimatic building of ICTA-UAB, which houses a pilot plant for nitrogen recovery and a greenhouse integrated into the roof, where the impact of the recovered nitrogen on tomato crops is tested. The process begins in the underground plant, where urine from waterless male urinals is stored and directed to a specialized reactor. In this reactor, the urine is mixed with a base to regulate its acidity, while microorganisms transform the urea in the urine into nitrate, a form of nitrogen that plants can absorb more easily.
The nitrate produced in the reactor is then used to irrigate the hydroponic tomato crops in the greenhouse located on the building's rooftop. According to the study, one cubic meter of treated yellow water yields 7.5 kg of nitrogen, which would allow the cultivation of 2.4 tons of tomatoes outdoors.
Although this is still a laboratory-scale study, the results show that the environmental and economic impact would be reduced if urine recovery were carried out on a larger scale, by connecting all the urinals in the building to the nitrogen recovery reactor. Experimental work is still being conducted, such as the analysis of pharmaceutical compounds consumed by people and their potential appearance in crop tissues.
Renting clothes can reduce the fashion industry's enormous environmental impact, but so far, the business models have not worked very well. The best chance of success is for a rental company to provide clothing within a niche market, such as specific sportswear, and to work closely with the suppliers and clothing manufacturers. This is shown by a study led by researchers at Chalmers University of Technology, Sweden, which highlights the measures that can make clothing rental a success.
The fashion industry is one of the most polluting industries and can account for up to ten percent of global greenhouse gas emissions, worldwide. In Sweden, over 90 percent of the clothes' climate impact is linked to the purchase of newly produced goods. Therefore, researchers at Chalmers University of Technology, the University of Borås and the research institute Rise have examined alternative, more sustainable business models for the clothing industry.
"Many people have clothes hanging in the closet that are rarely or never used. Renting clothes can extend the use of each garment and thus contribute to more sustainable consumption," says Frida Lind, Professor at Chalmers and one of the researchers behind the study.
In the study, the researchers analysed nine Swedish companies that have either tried and failed, or are ongoing in the process of creating a sustainable and desirable clothes rental company. From this analysis, the researchers identified three main business models for renting out clothes:
1. Membership model: customers become members and can then borrow clothes for a certain period of time, similar to a library. This model often had an enthusiast as its founder, with a focus on sustainable consumption.
2. Subscription model: customers pay a monthly fee to rent a certain number of garments. These startups worked on scaling up operations and attracting venture capital.
3. Individual rental model: the company would provide specific types of clothing to rent out, often in combination with other equipment, such as outdoor clothing paired with ski equipment.
Difficult to achieve profitability
By interviewing founders, managers and other key people from the nine Swedish companies, the researchers gained an understanding of each company's situation.
"What struck us was that it seemed so difficult for them to make their business profitable. Several had had to end their investments for various reasons," she says.
The researchers noted that although there was a willing customer base for renting clothing in this way, they observed several other challenges that made it difficult for companies to achieve profitability.
"Renting out clothes involves many steps where each item of clothing needs to be handled and inspected before it can be rented out again, which takes time. Companies also struggled with high costs for warehousing, logistics and laundry, for example. Especially for the subscription models, there were also difficulties in obtaining venture capital to be able to survive financially through the first phase of building the company. All this shows that these business models need time to establish themselves in the market," she says.
Specific markets performed best
At the same time, some of the business models worked better than others. Companies that focused on a specific market, such as outdoor clothing, were more successful and sustainable. Especially if they also had a local connection to an outdoor recreational area.
"They seem to have found their niche and seen that there is a specific need that the customer is willing to pay for each time they need to use that type of clothing," says Frida Lind.
The researchers also examined how the companies created value in collaboration with different stakeholders and concluded that certain collaborations were particularly valuable.
"Rental companies that worked closely with clothing manufacturers and suppliers, such as designers with a sustainability profile, benefited greatly from this as they were able to quickly get feedback on which types of clothing were most popular. They also gained valuable information about the quality of the garments, for example if there was something that often broke," she says.
Initiatives for change important
In the current study, the researchers have not investigated the environmental and climate impact of the business models specifically, but in general, the environmental effects of our clothes have already been well mapped. For example, previous research from Chalmers has shown that the actual production of garments accounts for 70 percent of the climate impact of Swedes' clothes throughout their life cycle, and 22 percent of the climate impact is caused by customers' shopping trips. In the European Union, five million tonnes of clothing are discarded each year - around 12 kilos per person, and in the USA, the average American generates 37 kilos of textile waste each year.
Frida Lind believes that there is a great deal of room for environmental benefits through reduced clothing purchases and extended use of existing garments – especially if it can be done without extra car journeys for consumers.
She emphasises that even if some of the companies and services in the study have not survived, all initiatives that can contribute to the sustainability transition are important. Not least because they help to change attitudes about clothing consumption and increase knowledge about what can and cannot work.
"Our study can be an important contribution to the fashion industry's sustainability transition, as it shows the possibilities of new business models in this industry. We hope that it can have an impact on decision-makers who need a basis for establishing incentives and financial motivation for a more sustainable fashion industry. Because we see that new and more sustainable business models require time and a long-term perspective to be able to establish themselves," she says.
Recommendations for the industry
Based on the study's results, the researchers give a number of recommendations to those who intend to try renting clothes as a business model:
Focus on niche markets based on target group and product type where the need is clear
Develop partnerships with suppliers to improve products based on rental experiences.
Think about logistics and transport in the rental model right from the start to be able to get the model scalable.
More about the research
The scientific article "Exploring renting models for clothing items – resource interaction for value creation" was published in the Journal of Business & Industrial Marketing. The authors are Frida Lind, Chalmers University of Technology, Agnes Andersson Wänström and Daniel Hjelmgren, University of Borås, and Maria Landqvist, Rise. The study has been financed with funds from the Swedish Energy Agency.
Facts and advice about textile consumption
In the European Union, five million tonnes of clothing are discarded each year - around 12 kilos per person, and in the USA, the average American generates 37 kilos of textile waste each year.
Over 90 percent of the total climate impact from Swedish clothing consumption is linked to the purchase of newly produced clothes, and 80 percent of our clothes' climate impact occurs during the production phase.
It also plays a big role how customers get to the stores. If they walk or cycle instead of driving, they reduce their climate impact by over 10 percent.
The most important thing that consumers can do is to extend the use of the garments that have already been produced. A t-shirt, for example, is used an average of 30 times. If it is instead used 60 times before it is replaced by a newly produced t-shirt, the climate impact can be halved.
Extended use can mean that one owner uses the garment for longer, or that several users share ownership. In addition to renting or borrowing clothes, this can be done, for example, by shopping and selling second-hand, arranging clothes swap days or giving away clothes to someone who continues to use them.
A previous Chalmers study has shown that the actual production of garments accounts for 70 percent of the climate impact of Swedes' clothes throughout their life cycle. 22 per cent of the climate impact is caused by customers' shopping trips, 4 per cent by distribution to customers and 3 per cent by washing and drying clothes.
Foie gras, translated from French as “fatty liver”, is known in Germany as “Gänsestopfleber” (goose liver). For animal welfare reasons, the so-called “force-feeding” has been criticized for a long time, and in many countries its production or even sale is prohibited. Substitute products have so far been unable to imitate the unique taste and texture of foie gras.
Researchers led by Thomas Vilgis from the Max Planck Institute for Polymer Research (MPI-P) in Mainz, together with colleagues from the University of Southern Denmark, have now used various scientific methods to examine the structure of real foie gras and developed an alternative based on these findings.
“It has always been a goal to reproduce the taste and texture of real foie gras while not losing sight of animal welfare,” says Thomas Vilgis, himself a passionate amateur chef and scientist at the MPI-P.
For their investigations, the researchers used both microscopic methods to determine the fat content or the proportion of collagen fibers, which account for a large part of the mouthfeel, and so-called rheological investigations. In the latter, the “processing” of the foie gras in the mouth is simulated by means of appropriate mechanical setups and expressed in figures.
In order to produce a new, animal-friendly foie gras, the researchers cooked collagen-rich tissue such as skin and used it to make a gel. This gel is then mixed with liver and fat in the correct proportions to form a pâté. However, despite similar ingredients, this mixture could not adequately imitate the “real” product, and even the systematic addition of collagen did not produce a better result. The scientists then had the idea of treating the fat with the goose's own lipases. Lipases are enzymes that help to digest fat in the body and mimic the natural processes in the duck's body.
The pâté produced in this way closely mimics the properties of real foie gras. This is mainly due to the restructured fat, because it is only the lipase treatment that allows the formation of large (irregular) fat aggregates, as they also occur in foie gras. This is the best way to imitate the mouthfeel and, above all, the melt. Collagen-enriched pâtés do not allow for this.
For Vilgis and his team, it was important not to add any external ingredients or additives to the foie gras. Vilgis has already applied for a patent for the recipe and hopes to work with companies that can help in the production of the alternative product. He would also like to work with sensory experts who can help him refine the taste and smell of foie gras.
The research results have now been published in the journal Physics of Fluids.
Famine, Affluence, and Morality. Peter Singer. Philosophy and Public Affairs, vol. 1, no. 1 (Spring 1972), pp. 229-243 [revised edition]. As I write this, in ...
* In TOM REGAN & PETER SINGER (eds.), Animal Rights and Human Obligations. New Jersey: Prentice-Hall, 1989, pp. 148-. 162. Page 2. men are; dogs, on the other ...
That's an important step forward, and a sign that over the next forty years we may see even bigger changes in the ways we treat animals. Peter Singer. February ...
In Practical Ethics, Peter Singer argues that ethics is not "an ideal system which is all very noble in theory but no good in practice." 1 Singer identifies ..
Beasts of. Burden. Capitalism · Animals. Communism as on ent ons. s a een ree. Page 2. Beasts of Burden: Capitalism - Animals -. Communism. Published October ...
Nov 18, 2005 ... Beasts of Burden forces to rethink the whole "primitivist" debate. ... Gilles Dauvé- Letter on animal liberation.pdf (316.85 KB). primitivism ..
New study explores what motivates LGB parents to have more children
“Neither stigma nor social support — but rather age, economic status, number of children, and religiosity — are the key predictors of LGB parents’ desire to expand their families.” A new study led by Dr. Geva Shenkman-Lachberg of the Dina Recanati School of Medicine at Reichman University, in collaboration with Yuval Shaia of Reichman University and Dr. Kfir Ifrah of Ruppin Academic Center, found that only sociodemographic factors — including the parent’s age, number of current children, economic status, and level of religiosity — predict the desire and intention to have more children among lesbian, gay, and bisexual (LGB) parents. In contrast to the findings of previous studies, experiences of discrimination, stigma, and social support were not found to have a significant impact on parental aspirations. The researchers now aim to further explore the reasons behind these findings.
The research team explored the desire, intention, and assessment of the likelihood of having additional children among LGB individuals who are already parents. The study, published last week in the Journal of Reproductive and Infant Psychology, is the first to focus on the motivations for family expansion among LGB parents. It examined three measures of parental aspirations — desire, intention, and estimated probability — in the context of parenthood achieved through fertility treatments.
The study included 234 LGB parents with an average age of 40.23, surveyed between November 2022 and February 2024. Participants completed questionnaires addressing a wide range of factors that may influence the motivation to have additional children. The variables examined included sociodemographic characteristics (parent’s age, gender, education level, economic status, religiosity, marital status, number of children, and place of residence); factors related to perceptions of the parental role (investment in parenting, satisfaction with parenting, sense of parental competence, and parental integration); social variables (social support, experiences of discrimination, and stigma); as well as a cultural variable — pronatalism, which reflects sociocultural values that encourage childbirth and parenthood.
As one of the first studies to examine motivations for having additional children among LGB parents, the researchers based their hypotheses on previous findings from studies conducted among LGB individuals who were not yet parents. These earlier studies found that, alongside sociodemographic variables, social factors also had a significant impact. For example, non-parent LGB individuals who experienced lower levels of social support and higher levels of stigma and discrimination reported lower desire and intention to become parents. Accordingly, the researchers hypothesized that similar patterns would emerge among LGB parents — that exposure to stigma and discrimination or a lack of social support would be associated with decreased motivation to expand their families.
However, contrary to the initial hypothesis and previous findings from studies of non-parent LGB individuals, the current study found that only sociodemographic factors were significant predictors of motivation for additional children. Younger parental age, fewer existing children, higher economic status, and greater religiosity were the only variables found to be associated with the desire, intention, and estimated likelihood of bringing additional children into the world. In contrast, social support, stigma, discrimination, perceptions of the parental role, and pronatalist attitudes were not found to be significantly linked with aspirations for family expansion, once sociodemographic variables were accounted for within the statistical prediction model.
Dr. Geva Shenkman Lachberg, Dina Recanati School of Medicine: “The current study is particularly relevant in the Israeli context — a country that reveres childbirth and parenthood, with one of the highest average numbers of children among OECD countries. Israel is also known for its widespread use of assisted reproductive technologies and generous government funding, including nearly unlimited cycles of fertility treatment. Within this ‘parenting empire’, it is important to understand what motivates LGB parents to have more children — especially given the significant challenges they have faced over the years, such as restrictions on surrogacy in Israel.
“While previous studies have highlighted the impact of stigma, discrimination, and lack of social support on parenthood aspirations among sexual minorities, it seems that these factors carry less weight among LGB parents. It may be that after they have succeeded in becoming parents — effectively breaking the glass ceiling — they are accepted into the social consensus, and it is the sociodemographic factors that remain significant. In this sense, the emerging picture closely resembles the one we are familiar with among heterosexual parents.”
This study, one of the first to address the motivations for having additional children among LGB parents who have used assisted reproductive technologies, makes a significant contribution to understanding gay parenthood in the Israeli context.
