Academics from the University of Leeds and specialists from Procter & Gamble, makers of Ariel, Daz, Bold, Fairy and Lenor, have wrung out new insight into how laundering clothing affects fading, colour runs and microfibre release.

Every load of washing releases hundreds of thousands of microfibres — tiny strands that are flushed down the drain. Many reach beaches and oceans where they can remain for many years and be swallowed by sea creatures.

In what is the first research into wash cycle duration that used both laboratory and real consumer testing, they found that reducing both washing cycle length and water temperature can significantly extend the life of garments and reduce the quantity of dye and microfibres shed into the environment.

Report lead author Lucy Cotton, from the University’s School of Design, said: “We are increasingly familiar with the environmental threat posed by throwaway fast fashion, but we also know that consumers claim their clothes can lose their fit, softness and colour after fewer than five washes — this means it’s more likely they will ditch them long before they are worn out.

“Using shorter, cooler washes is a simple way everyone can make their clothes last longer and keep them out of landfill.”

Dr Cotton worked with Dr Adam Hayward and Dr Neil Lant from P&G’s Newcastle Innovation Centre, as well as Leeds colleague Dr Richard Blackburn. Their findings are published today in the journal Dyes and Pigments.

Mimicking average household loads, they washed 12 dark and eight brightly-coloured t-shirts, together with white fabric squares to test colour-fastness.

Conventional domestic washing machines and Ariel pods of biological detergent were used, comparing 30 minute cycles at 25°C, and 85 minute cycles at 40°C (both with 1,600rpm spins) for 16 cycles each. The research was repeated and validated with authentic loads of dirty laundry provided by UK consumers.

A series of tests were carried out on the garments and fabric squares, and the washing machine waste water analysed. Chemical analysis distinguished individual dyes washed out of the clothing, and microfibres were collected and weighed.

The tests established:

• There was significantly less colour loss in the t-shirts that were washed using the cooler, quicker cycle;
• Quicker, cooler washes decreased dye transfer from coloured washing;
• Significantly less microfibres were released into wastewater during the quicker, cooler wash.

The researchers found washing with a quicker, cooler cycle reduced the amount of microfibre release into the environment by up to 52%, and cut dye release by up to 74%.

Dr Blackburn, who heads the Sustainable Materials Research Group at Leeds, said: “Our findings can help tackle the issue of ‘invisible’ plastics in the environment.

“Synthetic microfibres are released every time textiles are washed and account for more than a third of all plastic reaching the ocean. But microfibres from cotton and other natural sources are found in even greater numbers in the sea, and we’re worried about their impact too.

“Our research shows that consumers can actively reduce the number of microfibres released from their own clothing simply by washing in quicker, cooler cycles.”

What is more, washing clothes at 20°C rather than 40°C saves approximately 66% of the energy used per load — according to the Energy Saving Trust, providing even more reason to use quicker, cooler cycles to reduce energy use and CO2 emissions.

Dr Lant, a Procter & Gamble Research Fellow, added: “Advances in detergent technology, especially in sustainable ingredients such as enzymes, are allowing consumers to get excellent cleaning results in colder and quicker washes.

“It’s well known that these cycles reduce our energy bills and carbon footprint, but our partnership with the University of Leeds is helping us understand how they also slow down the ageing of clothes — keeping us looking smart, saving us money replacing garments and helping the environment. It’s a real win win win.”

Further information:

“Improved garment longevity and reduced microfibre release are important sustainability benefits of laundering in colder and quicker washing machine cycles” is published on 14 January 2019 in Dyes and Pigments.

“Vital exhaustion, commonly referred to as burnout syndrome, is typically caused by prolonged and profound stress at work or home,” said study author Dr. Parveen K. Garg of the University of Southern California in Los Angeles. “It differs from depression, which is characterised by low mood, guilt, and poor self-esteem. The results of our study further establish the harm that can be caused in people who suffer from exhaustion that goes unchecked.”

Atrial fibrillation is the most common form of heart arrhythmia. It is estimated that 17 million people in Europe and 10 million people in the US will have this condition by next year, increasing their risk for heart attack, stroke, and death. Yet, what causes atrial fibrillation is not fully understood.

Psychological distress has been suggested as a risk factor for atrial fibrillation, but previous studies showed mixed results. In addition, until now, the specific association between vital exhaustion and atrial fibrillation had not been evaluated.

The researchers in this study surveyed more than 11,000 individuals for the presence of vital exhaustion, anger, antidepressant use, and poor social support. They then followed them over a period of nearly 25 years for the development of atrial fibrillation.

Participants with the highest levels of vital exhaustion were at a 20% higher risk of developing atrial fibrillation over the course of follow-up compared to those with little to no evidence of vital exhaustion.

While further study is needed to better understand the observed relationship, Dr. Garg noted that two mechanisms are likely at play. “Vital exhaustion is associated with increased inflammation and heightened activation of the body’s physiologic stress response,” he said. “When these two things are chronically triggered that can have serious and damaging effects on the heart tissue, which could then eventually lead to the development of this arrhythmia.”

No connections were found between anger, antidepressant use, or poor social support and development of atrial fibrillation. “The findings for anger and social support are consistent with prior research but two previous studies did find a significant association between antidepressant use and an increased risk of atrial fibrillation. Clearly, more work still needs to be done,” said Dr. Garg.

Further research is also needed to identify concrete actions for doctors to help patients with exhaustion, said Dr. Garg.

He concluded: “It is already known that exhaustion increases one’s risk for cardiovascular disease, including heart attack and stroke. We now report that it may also increase one’s risk for developing atrial fibrillation, a potentially serious cardiac arrhythmia. The importance of avoiding exhaustion through careful attention to — and management of — personal stress levels as a way to help preserve overall cardiovascular health cannot be overstated.”

Story Source:

Materials provided by European Society of Cardiology. Note: Content may be edited for style and length.

AVs remove people from the hands-on task of driving and thus pose a complex challenge to today’s accident tort law, which primarily punishes humans. Legal experts anticipate that, by programming driving algorithms, self-driving car manufacturers, including car designers, sensor vendors, software developers, car producers, and related parties who contribute to the design, manufacturing, and testing, will have a direct influence on traffic. While these algorithms make manufacturers indispensable actors, with their product’s liability potentially playing a critical role, policy makers have not yet devised a quantitative method to assign the loss between the self-driving car and the human driver.

To tackle this problem, researchers at Columbia Engineering and Columbia Law School have developed a joint fault-based liability rule that can be used to regulate both self-driving car manufacturers and human drivers. They propose a game-theoretic model that describes the strategic interactions among the law maker, the self-driving car manufacturer, the self-driving car, and human drivers, and examine how, as the market penetration of AVs increases, the liability rule should evolve.

Their findings are outlined in a new study to be presented on January 14 by Sharon Di, assistant professor of civil engineering and engineering mechanics, and Eric Talley, Isidor and Seville Sulzbacher Professor of Law, at the Transportation Research Board’s 99th Annual Meeting in Washington, D.C

While most current studies have focused on designing AVs’ driving algorithms in various scenarios to ensure traffic efficiency and safety, they have not explored human drivers’ behavioral adaptation to AVs. Di and Talley wondered about the “moral hazard” effect on humans, whether with exposure to more and more traffic encounters with AVs, people might be less inclined to exercise “due care” when faced with AVs on the road and drive in a more risky fashion.

“Human drivers perceive AVs as intelligent agents with the ability to adapt to more aggressive and potentially dangerous human driving behavior,” says Di, who is a member of Columbia’s Data Science Institute. “We found that human drivers may take advantage of this technology by driving carelessly and taking more risks, because they know that self-driving cars would be designed to drive more conservatively.”

The researchers used game theory to model a world with interacting players who try to select their own actions to optimize their own goals. The players — law makers, AV manufacturers, AVs, and human drivers — have different goals in the transportation ecosystem. Law makers want to regulate traffic with improved efficiency and safety, self-driving car manufacturers are profit-driven, and both self-driving cars and human drivers interact on public roads and seek to select the best driving strategies. To capture the complex interaction among all the players, the researchers applied game theory methods to see which strategy each player settles on, so that others will not take advantage of his or her decisions.

The hierarchical game helped the team to understand the human drivers’ moral hazard (how much risk drivers might decide to take on), the AV manufacturer’s impact on traffic safety, and the law maker’s adaptation to the new transportation ecosystem. They tested the game and its algorithm on a set of numerical examples, offering insights into behavioral evolution of AVs and HVs as the AV penetration rate increases and as cost or environment parameters vary.

The team found that an optimally designed liability policy is critical to help prevent human drivers from developing moral hazard and to assist the AV manufacturer with a tradeoff between traffic safety and production costs. Government subsidies to AV manufacturers for the reduction of production costs would greatly encourage manufacturers to produce AVs that outperform human drivers substantially and improve overall traffic safety and efficiency. Moreover, if AV manufacturers are not regulated in terms of AV technology specifications or are not properly subsidized, AV manufacturers tend to be purely profit-oriented and destructive to the overall traffic system.

“The tragic fatality in Arizona involving a self-driving automobile elicited tremendous attention from the public and policy makers about how to draw the lines of legal liability when AVs interact with human drivers, cyclists, and pedestrians,” Talley adds. “The emergence of AVs introduces a particularly thorny type of uncertainty into the status quo, and one that feeds back onto AV manufacturing and design. Legal liability for accidents between automobiles and pedestrians typically involves a complex calculus of comparative fault assessments for each of the aforementioned groups. The introduction of an autonomous vehicle can complicate matters further by adding other parties to the mix, such as the manufacturers of hardware and programmers of software. And insurance coverage distorts matters further by including third party stakeholders. We hope our analytical tools will assist AV policy-makers with their regulatory decisions, and in doing so, will help mitigate uncertainty in the existing regulatory environment around AV technologies.”

Di and Talley are now looking at multiple AV manufacturers that target different global markets with different technological specifications, making the development of legal rules even more complex.

“We know that human drivers will take more risks and develop moral hazard if they think their road environment has become safer,” Di notes. “It’s clear that an optimal liability rule design is crucial to improve social welfare and road safety with advanced transportation technologies.”

The study is titled “Liability Design for Autonomous Vehicles and Human-Driven Vehicles: A Hierarchical Game-Theoretic Approach.”