New study estimates over 5.5 million U.S. adults use hallucinogens

Past 12-month LSD use rate increased from 0.9 percent in 2002 to 4 percent in 2019

Peer-Reviewed Publication

COLUMBIA UNIVERSITY'S MAILMAN SCHOOL OF PUBLIC HEALTH

August 18, 2022 -- Hallucinogen use has increased since 2015, overall and particularly among adults 26 and older, while use decreased in adolescents aged 12–17 years according to a new study by Columbia University Mailman School of Public Health and Columbia University Irving Medical Center. Estimates of over 5.5 million people in the U.S. used hallucinogens in the past year in 2019, which represents an increase from 1.7 percent of the population ages 12 years and over in 2002 to 2.2 percent in 2019. 

LSD use between 2002 and 2019 increased overall and in all age groups with the past 12-month rate increasing from 0.9 percent in 2002 to 4 percent in 2019 for those 18-25 years of age.  Conversely, PCP use between 2002 and 2019 decreased, as did the drug Ecstasy since 2015. The study is the first to provide formal statistical analyses of trends in prevalence of hallucinogen use overall and by age groups during the last two decades. 

The findings are published online in the peer-reviewed journal Addiction.

To assess trends in hallucinogen use in the U.S. general population, the researchers analyzed data from the National Survey on Drug Use and Health (NSDUH) from 2002 to 2019 for participants 12 years of age and older.

The use of hallucinogens -- a broad category of psychoactive substances, including “classic” psychedelics such as LSD -- are mostly designated as Schedule I drugs in the U. S., and may entail risk for adverse consequences including anxious reactions, confusion, acute delusional states and a prolonged sense of fear and dread. LSD and Ecstasy and several other hallucinogens are associated with an increased risk of autonomic, endocrine, cardiovascular and neurological adverse effects including elevated blood pressure, heart rate and loss of appetite, tremors and seizures. PCP is considered to be one of the most dangerous hallucinogens, and known to cause adverse effects similar to LSD and ecstasy, but unlike those drugs, PCP can lead to hostile and violent behaviors that may result in severe trauma. 

“While new findings suggesting benefits from use of certain hallucinogens among a range of cognitive areas are being published at a rapid rate, there are still gaps in knowledge concerning safe hallucinogen use, and evidence for potential adverse effects even with professionally supervised use that warrant attention.” said Ofir Livne, MD, MPH, postdoctoral fellow in the Department of Epidemiology at Columbia Mailman School, and first author. 

From 2002 to 2019, the prevalence of 12-month LSD use increased significantly overall and among respondents aged 12–17 years. However, the prevalence of great risk for regular LSD use decreased significantly overall for the years 2002–14, and among all age groups.

“Our finding of an upward trend in 12-month LSD use, overall and by age, matches our finding of a downward trend in perception of LSD as risky,” said Deborah Hasin, PhD, professor of epidemiology (in psychiatry) at the Columbia University Irving Medical Center, and senior author. “Factors such as changes in risk perception, in the specific types of drugs available and in expectations of beneficial effects of ‘microdosing’ may all have led to increased use of certain hallucinogens in recent years.”

According to author Livne, “Given the recent media coverage showing that an increasing number of adults may be reporting positive effects of ‘microdosing’ and expecting therapeutic benefits of hallucinogens without negative effects, our findings merit a comprehensive examination of time trends and motives for hallucinogen frequency and quantity of use.”

“In light of popular media reports of a forthcoming ‘psychedelic revolution’ with commercialization and marketing that may further reduce public perception of any risk, researchers, clinicians and policymakers should increase their attention to the rising rates of unsupervised hallucinogen use among the general public,” observes Hasin. “Our results highlight such use as a growing public health concern and suggest that the increasing risk of potentially unsupervised hallucinogen use warrants preventive strategies.“

Co-authors are Dvora Shmulewitz, Department of Psychiatry, Columbia University Irving Medical Center, and Claire Walsh, New York State Psychiatric Institute.

The study was supported by the National Institute on Drug Abuse (T32DA031099). 

Columbia University Mailman School of Public Health

Founded in 1922, the Columbia University Mailman School of Public Health pursues an agenda of research, education, and service to address the critical and complex public health issues affecting New Yorkers, the nation and the world. The Columbia Mailman School is the fourth largest recipient of NIH grants among schools of public health. Its nearly 300 multi-disciplinary faculty members work in more than 100 countries around the world, addressing such issues as preventing infectious and chronic diseases, environmental health, maternal and child health, health policy, climate change and health, and public health preparedness. It is a leader in public health education with more than 1,300 graduate students from 55 nations pursuing a variety of master’s and doctoral degree programs. The Columbia Mailman School is also home to numerous world-renowned research centers, including ICAP and the Center for Infection and Immunity. For more information, please visit www.mailman.columbia.edu.

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JOURNAL

Addiction

DOI

10.1111/add.15987 

ARTICLE TITLE

Adolescent and adult time trends in US hallucinogen use, 2002–19: any use, and use of ecstasy, LSD and PCP

SEE  

https://plawiuk.blogspot.com/search?q=LSD

https://plawiuk.blogspot.com/search?q=MKULTRA

https://plawiuk.blogspot.com/search?q=CIA

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Aldous Huxley - somaweb.org
The intellectual, satirical, spiritual, hypnotic, and philosophical world of Aldous Huxley.

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SHUNNING

Social exclusion more common form of bullying than physical, verbal aggression

MU study finds perceptions of popularity, social status at school impact social exclusion.

UNIVERSITY OF MISSOURI-COLUMBIA

COLUMBIA, Mo. – Bullying is typically portrayed in popular culture as either physical aggression, such as pushing and kicking, or verbal aggression, such as threats and derogatory insults.  

However, a new study at the University of Missouri highlights the damaging social and emotional toll caused by “relational aggression,” which is the most common form of bullying and involves socially excluding peers from group activities and spreading harmful rumors. 

“Previous studies suggest when a kid is excluded from social activities by their peers at school, the outcomes for that kid both short-term and long-term will be just as detrimental as if they got kicked, punched or slapped every day. So this study sheds light on the social exclusion youth often face,” said Chad Rose, an associate professor in the MU College of Education and Human Development and director of the Mizzou Ed Bully Prevention Lab. 

In the study, Rose analyzed survey results that were part of a broader school climate assessment conducted in 26 middle and high schools across five school districts in the southeastern United States. More than 14,000 students were asked if they agreed or disagreed with statements reflecting pro-bullying attitudes, perceived popularity and relational aggression.  

Examples of survey statements included “A little teasing does not hurt anyone,” “I don’t care what mean things kids say as long as it’s not about me,” “In my group of friends, I am usually the one who makes decisions,” and “When I am mad at someone, I get back at them by not letting them be in my group anymore.”  

“What we found is kids that perceive themselves as socially dominant or popular endorse pro-bullying attitudes, yet they don’t perceive themselves as engaging in relational aggression,” Rose said. “There was another group that did not perceive themselves as socially dominant or popular, but they endorsed pro-bullying attitudes and engaged in relational aggression. So, the first group thought bullying was OK but did not see themselves as engaging in it even if they actually were excluding others. While the second group that admitted to engaging in relational aggression may have been excluding others as an attempt to jockey for the position of being more socially dominant and climb the social hierarchy.” 

Rose added there was a third group of respondents who reported both low levels of pro-bullying attitudes and low levels of relational aggression, known as non-aggressors or bystanders.  

“What’s interesting about bystanders is that they often perpetuate bullying, meaning they serve as social reinforcers and are around when it’s happening,” Rose said. “We teach the famous tagline, ‘See something, say something,’ but in practice, it is hard for kids to intervene and assess conflicts quickly – it’s hard even for adults. If we see two kids in a physical fight, we feel an obligation to break it up. But when we see kids being excluded by their peers, adults don’t always seem to view it as equally damaging, and that’s the scary part.” 

Teachers, parents and community members can all assist at-risk youth by celebrating their individuality, Rose said.  

“When kids are in school, sameness often gets celebrated, but when kids grow up to become adults, individuality is what makes us stand out and excel in our jobs and in life,” Rose said. “Individuality should be interwoven in some of the messages we as adults send in our schools, in our families and in our neighborhoods.” 

Another practical tip teachers can implement right away is embedding social communication skills within their daily curriculum, Rose said.  

“In addition to establishing academic objectives for group projects, teachers can monitor how well the students are inviting the input of others’ ideas through positive, encouraging conversations,” Rose said. “Teachers should give specific praise when they see respectful and inclusive behavior in action, because teaching and reinforcing these skills are just as important as the math, science and history lessons.” 

Rose has been researching bullying for 17 years and became interested in the topic during his first job after college as a high school special education teacher working with at-risk youth who engaged in violent or aggressive behavior.  

“I had kids coming back to school from juvenile detention facilities and realized I didn’t just want to only work with the most academically gifted and well-behaved kids, I wanted to help every kid that comes through the door, especially those who have been traditionally marginalized,” Rose said. “Rather than simply suspending or expelling kids from school, I focused on helping them build skills and develop interventions that emphasize social communication, respect and empathy.” 

Rose added that if kids aren’t taught the skills to effectively communicate their thoughts, wants and needs, they may be more likely to show aggressive behavior, and although not all kids have to be friends, showing respect to all is essential. 

“Bullying does not begin or end with the school bells, it is a community issue,” Rose said. “I think, as adults, we have to be more aware of what we’re teaching our kids in terms of how we interact socially, as schools are a reflection of our communities.” 

“Survey of secondary youth on relational aggression: impact of bullying, social status, and attitudes” was published in Preventing School Failure: Alternative Education for Children and Youth. 

Assessing the toxicity of Reddit comments

Peer-Reviewed Publication

PEERJ

Researchers analyze over 2 billion posts and comments from cross-community Redditors to assess how toxicity changes depending on the community in which they participate

New research, published in the Open Access journal PeerJ Computer Science, which analyses over 87 million posts and 2.205 billion comments on Reddit from more than 1.2 million unique users, examines changes in the online behavior of users who publish in multiple communities on Reddit by measuring “toxicity”.

User behavior toxicity analysis showed that 16.11% of users publish toxic posts, and 13.28% of users publish toxic comments. 30.68% of users publishing posts, and 81.67% of users publishing comments, exhibit changes in their toxicity across different communities – or subreddits - indicating that users adapt their behavior to the communities’ norms.

The study suggests that one way to limit the spread of toxicity is by limiting the communities in which users can participate. The researchers found a positive correlation between the increase in the number of communities and the increase in toxicity but cannot guarantee that this is the only reason behind the increase in toxic content. 

Various types of content can be shared and published on social media platforms, enabling users to communicate with each other in various ways. The growth of social media platforms has unfortunately led to an explosion of malicious content such as harassment, profanity, and cyberbullying. Various reasons may motivate users of social media platforms to spread harmful content. It has been shown that publishing toxic content (i.e., malicious behavior) spreads--the malicious behavior of non-malicious users can influence non-malicious users and make them misbehave, negatively impacting online communities.

“One challenge with studying online toxicity is the multitude of forms it takes, including hate speech, harassment, and cyberbullying. Toxic content often contains insults, threats, and offensive language, which, in turn, contaminate online platforms. Several online platforms have implemented prevention mechanisms, but these efforts are not scalable enough to curtail the rapid growth of toxic content on online platforms. These challenges call for developing effective automatic or semiautomatic solutions to detect toxicity from a large stream of content on online platforms,” say the authors, PhD (ABD) Hind Almerekhi, Dr Haewoon Kwak and Professor Bernard J. Jansen.  

 

“Monitoring the change in users’ toxicity can be an early detection method for toxicity in online communities. The proposed methodology can identify when users exhibit a change by calculating the toxicity percentage in posts and comments. This change, combined with the toxicity level our system detects in users’ posts, can be used efficiently to stop toxicity dissemination.”

 

The research team, with the aid of crowdsourcing, built a labeled dataset of 10,083 Reddit comments, then used the dataset to train and fine-tune a Bidirectional Encoder Representations from Transformers (BERT) neural network model. The model predicted the toxicity levels of 87,376,912 posts from 577,835 users and 2,205,581,786 comments from 890,913 users on Reddit over 16 years, from 2005 to 2020. This study utilized the toxicity levels of user content to identify toxicity changes by the user within the same community, across multiple communities, and over time. For the toxicity detection performance, the fine-tuned BERT model achieved a 91.27% classification accuracy and an Area Under the Receiver Operating Characteristic Curve (AUC) score of 0.963 and outperformed several baseline machine learning and neural network models. 

 

 

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JOURNAL

PeerJ Computer Science

DOI

10.7717/peerj-cs.1059 

METHOD OF RESEARCH

Data/statistical analysis

ARTICLE TITLE

Investigating Toxicity changes of cross-community Redditors from 2 Billion Posts and Comments

Researchers track twitter to learn what people valued in New York City parks after COVID-19 pandemic

Peer-Reviewed Publication

NORTH CAROLINA STATE UNIVERSITY

North Carolina State University researchers found they could use Twitter to understand changes in what New York City park users valued most about four iconic city parks before and after COVID-19 lockdowns went into effect. The researchers also found Twitter useful for tracking complaints about individual parks.

The findings indicate social media could be an important tool for park managers, park planners or others to respond in real time to changes in users’ needs or to plan for future parks, potentially faster than using traditional survey-based methods.

“We found that you can pull out detail about individual parks, as well as track what people value in parks, complaints they had about specific events, and even broader societal issues that people are talking about,” said study co-author Aaron Hipp, associate professor of community health and sustainability at NC State. “While we have some additional work to automate this and get closer to real-time monitoring, we think our findings indicate that parks can monitor this information and feel confident that some of the social media traffic can be a pretty reliable reflection of public sentiments.”

For the study, researchers tracked tweets about Central Park in Manhattan, Prospect Park in Brooklyn, Flushing Meadows in Queens and the Bronx Park from March 2019 to February 2020, and then from March 2020 to February 2021. They used natural language processing and topic modeling techniques to analyze a total of 71,792 tweets, which excluded retweets, tweets from influencers, bots, and tweets containing fewer than three words. Overall, they found tweets about Central Park grew 18% and tweets about Prospect Park grew by 87%. Meanwhile, tweets about Flushing Meadows declined 71% and tweets about Bronx Park fell 32%.

Researchers said the findings reflect the effects of a COVID-19 stay-at-home order. Since outdoor recreation was limited to solitary exercise, parks and trails became popular destinations after March 2020. However, this trend did not seem to hold true across all parks due to their distinct offerings.

“Flushing Meadows is famous for sports events, but during the pandemic, those were mostly canceled,” said the study’s lead author Jing-Huei Huang, postdoctoral research scholar at NC State. “In Bronx Park, people tended to tweet about the zoo and Botanical Garden, but those were closed, so that was reflected in the decline in tweets.”

Tweets about physical activity such as walking, jogging and biking grew in all four parks during the pandemic. The researchers also saw concerns about social distancing and related issues in all four.

“In all four parks, we saw participating in physical activity outdoors was particularly important when people had to keep distant from each other, and they were not able to participate in social activities,” Huang said. “We were also able to capture negative feelings when people were upset seeing crowds in parks, or when people weren’t wearing masks,” Huang added. “It’s sending useful signals to the management team.”

They also captured tweets about specific incidents in each park that reflected larger social concerns. For example, they saw a peak in tweets about racial discrimination in May 2020 after the Central Park birdwatching incident, when Amy Cooper, a white woman, called the police on a Black man, Christian Cooper, who was birdwatching. They also saw complaints about Flushing Meadows becoming a “giant parking lot” amid advocacy for a new greenway to increase access and ensure pedestrian safety.

In a follow-up study, they’re planning to compare data gathered using traditional surveys to what they found on social media.

“A long-range goal is to be able to get this feedback in real time, so park managers could launch programming in response,” Hipp said. “For example, amid a surge in demand, you could open a street nearby for waking or biking. There is also big potential here for the evaluation of programs and events especially when decisions are made on the fly, such as during COVID. This social media data can provide a retrospective opportunity to evaluate what people were saying about the park, a specific program or event.”

The paper, “Exploring values through Twitter data associated with urban parks pre- and post-COVID-19,” was published online in Landscape and Urban Planning. Co-authors included Myron F. Floyd and Laura G. Tateosian. The study is part of the project “Greenspace Characteristics and their Associations with Population Health” funded by USDA Forest Service Grant/Agreement Number: 16-JV-11330144-065

-oleniacz-

Note to authors: The abstract follows.

“Exploring values through Twitter data associated with urban parks pre- and post-COVID-19”

Authors: Jing-Huei Huang, Myron F. Floyd, Laura G. Tateosian and J. Aaron Hipp

Published online in Landscape and Urban Planning.

DOI: 10.1016/j.landurbplan.2022.104517

Abstract: Since school and business closures due to the evolving COVID-19 outbreak, urban parks have been a popular destination, offering spaces for daily fitness activities and an escape from the home environment. There is a need for evidence for parks and recreation departments and agencies to base decisions when adapting policies in response to the rapid change in demand and preferences during the pandemic. The application of social media data analytic techniques permits a qualitative and quantitative big-data approach to gain unobtrusive and prompt insights on how parks are valued. This study investigates how public values associated with NYC parks has shifted between pre- COVID (i.e., from March 2019 to February 2020) and postCOVID (i.e., from March 2020 to February 2021) through a social media microblogging platform –Twitter. A topic modeling technique for short text identified common traits of the changes in Twitter topics regarding impressions and values associated with the parks over two years. While the NYC lockdown resulted in much fewer social activities in parks, some parks continued to be valued for physical activity and nature contact during the pandemic. Concerns about people not keeping physical distance arose in parks where frequent human interactions and crowding seemed to cause a higher probability of the coronavirus transmission. This study demonstrates social media data could be used to capture park values and be specific per park. Results could inform park management during disruptions when use is altered and the needs of the public may be changing.

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JOURNAL

Landscape and Urban Planning

DOI

10.1016/j.landurbplan.2022.104517 

ARTICLE TITLE

Exploring public values through Twitter data associated with urban parks pre- and post- COVID-19

Study first to explore ‘walking’ sharks on the move in early life stages

Researchers compare walking, swimming in neonates with bulging bellies and slender juvenile epaulette sharks

Peer-Reviewed Publication

FLORIDA ATLANTIC UNIVERSITY

 

VIDEO: RESEARCHERS INVESTIGATED HOW WALKING AND SWIMMING CHANGES IN THE EPAULETTE SHARK’S EARLY DEVELOPMENT. view more 

CREDIT: CONNOR R. GERVAIS, PH.D.

A newly-discovered walking shark that breaks all of the rules for survival is the focus of a first-of-its-kind study by Florida Atlantic University and collaborators in Australia. Researchers investigated how walking and swimming changes in the epaulette shark’s (Hemiscyllium ocellatum) early development. This small (about 3 feet), reef-dwelling, benthic shark walks both in and out of water by wriggling its body and pushing with its paddle-shaped fins.

Found within the reef flats around Australia’s southern Great Barrier Reef, epaulette sharks experience short periods of elevated CO2 and hypoxia (low oxygen) as well as fluctuating temperatures as reef flats become isolated with the outgoing tide. Remarkably, this walking shark is capable of surviving complete anoxia (no oxygen) for two hours without adverse effects, and at a much higher temperature than most other hypoxia-tolerant animals.

The epaulette shark’s ability to move efficiently among micro-habitats under these challenging environmental conditions could directly impact their survival and physiological responses to climate change. Yet, very few studies have examined their kinematics (body movements). Those that have, only focused on adult-life stages. No study has specifically examined their locomotion (how they move) during early-life stages, until now.

As locomotor performance may be key to the epaulette sharks’ robust response to challenging environmental conditions, FAU researchers in collaboration with Australia’s James Cook University and Macquaire University examined differences in walking and swimming in neonate (newly-hatched) and juvenile walking sharks.

Neonates retain embryonic nutrition via an internalized yolk sac, which results in a bulging belly. In contrast, juveniles are more slender because they actively forage for worms, crustaceans and small fishes. During development, the yolk that the neonate sharks are storing starts to diminish as they develop into juveniles. As the yolk is depleted, the shark then begins to actively forage.

Because of dissimilarities in body shapes, researchers expected to see differences in locomotor performance in these walking sharks. To test their hypothesis, they examined neonate and juvenile locomotor kinematics during the three aquatic gaits they utilize – slow-to-medium walking, fast-walking and swimming – using 13 anatomical landmarks along the fins, girdles and body midline. They quantified axial body kinematics (velocity, tail beat amplitude and frequency and body curvature) and axial body bending, fin rotation and duty factor and tail kinematics.

Surprisingly, results published in the journal Integrative & Comparative Biology, showed that differences in body shape did not alter kinematics between neonate and juvenile walking sharks. Overall velocity, fin rotation, axial bending and tail beat frequency and amplitude were consistent between early life stages.

Data suggest that the locomotor kinematics are maintained between neonate and juvenile epaulette sharks, even as their feeding strategy changes. These findings suggest that submerged locomotion in neonates is not impacted by the yolk sac and the effects it has on body shape, as all aspects of submerged locomotion were comparable to that of the juveniles.

“Studying epaulette shark locomotion allows us to understand this species’– and perhaps related species’– ability to move within and away from challenging conditions in their habitats,” said Marianne E. Porter, Ph.D., senior author and an associate professor, Department of Biological Sciences, FAU’s Charles E. Schmidt College of Science. “In general, these locomotor traits are key to survival for a small, benthic mesopredator that maneuvers into small reef crevices to avoid aerial and aquatic predators. These traits also may be related to their sustained physiological performance under challenging environmental conditions, including those associated with climate change – an important topic for future studies.”

Studying the link between locomotion and the physiological mechanisms required to tolerate challenging environmental conditions represents an essential next step in understanding how this group of important mesopredators will respond to future ocean conditions.

“Investigating how locomotor performance changes over the course of early ontogeny – perhaps the most vulnerable life stages, in terms of predator-prey interactions and environmental stressors – can offer insights into the kinematic mechanisms that allow animals to compensate for constraints to meet locomotor and ecological demands,” said Porter.

Study co-authors are Andrea V. Hernandez, an undergraduate student in FAU’s Department of Biological Sciences; Connor R. Gervais, Ph.D., a research associate at Arc Centre of Excellence for Coral Reef Studies, James Cook University, and Macquarie University, Sydney, Australia; and Jodie L. Rummer, Ph.D., a professor of marine biology in the College of Science and Engineering, James Cook University, and a research associate at Arc Centre of Excellence for Coral Reef Studies.

This work was supported, in part, by a National Science Foundation CAREER award to Porter (IOS 1941713), and in part, by an Australian Research Council (ARC) Super Science Fellowship, ARC Early Career Discovery Award, and ARC Centre of Excellence for Coral Reef Studies research allocation awarded to Rummer.

- FAU -

About Florida Atlantic University:
Florida Atlantic University, established in 1961, officially opened its doors in 1964 as the fifth public university in Florida. Today, the University serves more than 30,000 undergraduate and graduate students across six campuses located along the southeast Florida coast. In recent years, the University has doubled its research expenditures and outpaced its peers in student achievement rates. Through the coexistence of access and excellence, FAU embodies an innovative model where traditional achievement gaps vanish. FAU is designated a Hispanic-serving institution, ranked as a top public university by U.S. News & World Report and a High Research Activity institution by the Carnegie Foundation for the Advancement of Teaching. For more information, visit www.fau.edu.

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JOURNAL

Integrative and Comparative Biology

DOI

10.1093/icb/icac127 

METHOD OF RESEARCH

Observational study

SUBJECT OF RESEARCH

Animals

ARTICLE TITLE

Aquatic Walking and Swimming Kinematics of Neonate and Juvenile Epaulette Sharks

Arctic mercury levels drop during the depths of the winter

First-ever measurements of total mercury levels in the polar night uncovered a 33 per cent drop compared to summer levels

Peer-Reviewed Publication

NORWEGIAN UNIVERSITY OF SCIENCE AND TECHNOLOGY

 

IMAGE: IT USED TO BE THAT RESEARCHERS DIDN'T STUDY WHAT HAPPENS IN THE ARCTIC DURING THE POLAR NIGHT BECAUSE IT WAS DIFFICULT TO WORK THERE. BUT OVER THE PAST DECADE, RESEARCHERS HAVE VENTURED INTO THIS ENVIRONMENT AND HAVE COME UP WITH SURPRISING FINDINGS. NORWAY'S RESEARCH-DEDICATED ICEBREAKER, KRONPRINS HÅKON, LAUNCHED IN 2017, IS AN IMPORTANT TOOL FOR THIS RESEARCH. view more 

CREDIT: ROBIN HJERTNES

Over the last decade, researchers have learned a lot about the polar night — discovering everything from how tiny marine critters migrate up and down in the sea in response to the weak light of the moon, to seabirds that dive into the pitch-black ocean to feast on bioluminescent plankton and krill.

But what is less well known is how the chemistry of Arctic Ocean water changes during this period, when the sun remains completely below the horizon for a full 24-hour day.

Now, in an article published in Nature Geoscience, Norwegian University of Science and Technology (NTNU) researchers report on a surprising trend they discovered in mercury levels in the ocean during the polar night.

“We found that total mercury concentrations in the Barents Sea decreased by about 33 percent from summer to winter,” said Stephen G. Kohler, a PhD candidate at NTNU’s Marine Chemistry and Biogeochemistry group in the Department of Chemistry, and first author of the article.

First-ever winter measurements

These measurements are the first-ever winter reports on this element in Arctic Ocean waters.They were conducted as a part of the Nansen Legacy Project, a 7-year-long collaborative between 10 Norwegian research institutions that involves studying the physical and biological aspects of the Barents Sea during all four seasons.

“Everything that we've done and know about the Arctic so far is entirely based on when we were allowed to go there, which was mostly in the summer,” Kohler said. “And the fact that now we have a snapshot of what's happening during the dark period gives us more insight into the entire mercury cycle.”

The problem with mercury

What happens with mercury levels in the Arctic matters because a specific toxic form of mercury, called methylmercury, can find its way into the food web.This poses risks to the health of animals at the top of the food chain, such as polar bears, and to northern indigenous people who consume contaminated fish and seals as a regular part of their diets.

But what Kohler and his colleagues are interested in is far more fundamental than this — they want to know the basic mechanisms by which mercury moves around in Arctic waters.

Manmade sources of mercury are transported to the Arctic via the air or in water. A large human-caused source of atmospheric mercury is from coal combustion. This mercury in the atmosphere can deposit onto the Arctic surface due to chemical reactions caused by sunlight. In addition, natural sources of mercury to the Arctic Ocean include  releases from melting permafrost into river water and land erosion.

As the planet warms over the next decades, more and more permafrost will melt, releasing more mercury to Arctic waters. That makes it important to understand how the element behaves, in all its different forms, and throughout the year, Kohler said.

Summer increase, winter decrease

Kohler and his colleagues observed higher mercury levels in surface seawater during the summer because the sun is up and everything has thawed, from sea ice to rivers, all of which can deliver mercury to the ocean.

“It’s warmer in the summer. So there’s more river water coming in, light in the atmosphere, and therefore, there's more mercury coming in,” Kohler said.

So you might expect that during the winter, when the Arctic is dark and frozen, mercury values would stay the same, since all the inputs have been stopped. But what Kohler and his colleagues saw, a 33 per cent drop in total mercury amounts compared to summer values, made them look for an explanation.

Particle scavenging

Kohler and his colleagues, including postdoc Nicolas Sanchez, were also measuring levels of other metals in ocean water, including iron and manganese.

And what they found was that manganese levels also decreased in the winter. In seawater, manganese can form small particles which then attract the mercury that’s in the seawater, in a process called scavenging.

These particles can become heavy enough to sink to the bottom of the sea. The researchers suggested that these particles are responsible for taking the mercury to deeper waters and sediments.

“Scavenging is when the particles are essentially just grabbing mercury from the water and taking it along for the ride,” Kohler said.

While this scavenging removes mercury from surface layers, it means increases in  mercury in sediments, where it is brought by the manganese particles.

More toxic mercury in the future

That’s not necessarily good news, even though it seems like it might be.

Once mercury reaches ocean sediments, it can be acted on by bacteria living in the sediments. These bacteria can transform mercury into its toxic form, methylmercury.

All this means that more toxic mercury could find its way into Arctic food webs, Kohler said.

“In the future, rising temperatures caused by climate change will enable more mercury to be released from mercury-rich permafrost around the Arctic circle during the summer,” he said. “This mercury is delivered to the Arctic Ocean via rivers. As a result, increasing amounts of mercury in surface waters indicate increasing amounts of mercury descending to the depths in winter, potentially resulting in more toxic methylmercury formation in the future Arctic Ocean.”

Reference: Kohler, S.G., Heimbürger-Boavida, LE., Petrova, M.V. et al. Arctic Ocean’s wintertime mercury concentrations limited by seasonal loss on the shelf. Nat. Geosci. (2022).  https://doi.org/10.1038/s41561-022-00986-3

CAPTION

It’s not easy studying the Arctic during the dark of the polar night. The Nansen Legacy project aims to shed light on the physical, chemical and biological processes in the Barents Sea across all four seasons.

CREDIT

Photo: Stephen Kohler

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JOURNAL

Nature Geoscience

DOI

10.1038/s41561-022-00986-3 

METHOD OF RESEARCH

Experimental study

SUBJECT OF RESEARCH

Not applicable

ARTICLE TITLE

Arctic Ocean’s wintertime mercury concentrations limited by seasonal loss on the shelf.

Middle-aged men led the violence in 1994 genocide in Rwanda

Study provides comprehensive information about participants

Peer-Reviewed Publication

OHIO STATE UNIVERSITY

Although most people who commit violence tend to be teens and young adults, a new study found that the perpetrators of the 1994 genocide in Rwanda were mostly middle-aged men.

Researchers found that 88% of people who participated in the genocide were men with an average age of 34 (when life expectancy peaked below 50), and who census statistics indicate were likely to be married. Between 229,069 and 234,155 individuals were found guilty of a violent offense.

“These are not the people that criminology theories would say are most likely to engage in violent crimes,” said Hollie Nyseth Nzitatira, lead author of the study and associate professor of sociology at The Ohio State University.

“Our results show that individuals involved in genocide don’t always fit the characteristics generally connected to other violent crimes.”

But the study did find one way in which participants in the 1994 genocide in Rwanda were like other violent criminals: A small number of them were responsible for a great many of the crimes. Findings showed 6% of people accounted for 25% of crimes in the genocide.

The study, published recently in the Journal of Peace Research, provides the most comprehensive information about the participants in one of the deadliest episodes of violence during the 20th century. Up to 1 million people were killed in the genocide in Rwanda, mostly members of the Tutsi ethnic group.

The researchers are the first to have obtained access to the complete records of nearly all 1.9 million trials of the gacaca courts, which the Rwandan government set up to try people suspected of participating in the genocide.

“The court data are certainly not perfect, but they provide the best way to know how many people and which people participated in crimes of genocide,” Nyseth Nzitatira said.

Study results showed that between 847,233 and 888,307 people participated in the genocide in Rwanda.  About one-fifth of them participated only in violent crimes, with the great majority only involved in property crimes – most often looting victims and their homes. A small number committed both property and violent crimes.

While women were less likely to perpetrate genocide, over 10,000 women committed violent offenses, with many more committing property crimes.

Overall, 88% of all participants were men, while about 95% of those who committed only violent offenses were men.

This goes along with other research showing that men commit most crimes and especially violent crimes, and it is also consistent with research showing that the Rwandan government encouraged men of the dominant Hutu ethnic group to kill Tutsi, Nyseth Nzitatira said.

The government rationale that Hutu men had to protect their families may also help explain why this study found that participants were relatively older.

“Our data indicate there was wide participation among Rwandans who were older than theories of ‘youth bulges’ in criminal activity would suggest,” Nyseth Nzitatira said.

“Many stories about the genocide focus on youth militias that became prominent, such as the Interahamwe. So, many people think it was 19- and 20-year-olds who were engaging in most of the violence, when it was really men who were in their early- to mid-30s.”

The median age for all participants was 34 – and that age did not change much when the researchers looked at just those who committed violent crimes or those who committed multiple crimes.

The life expectancy in Rwanda just before the genocide began was less than 50, Nyseth Nzitatira said, so the perpetrators were truly middle-aged.

Participants in the genocide were also likely married, which is not surprising given their age.  Statistics show that about 87% of 33-year-old men in Rwanda at the time of the genocide were married or had been married. “These men were told they had to protect their families, their wives and children, from the Tutsi who were supposedly invading their country,” Nyseth Nzitatira said.

Results showed that about 75% of those found guilty of any crimes of genocide, property damage or violence against people, were found guilty of only one crime. But 6% of participants accounted for 25% of all crimes.

That included 11% of people who accounted for 25% of violent crimes and 6% who accounted for 25% of all property crimes.

“The fact that a small number of people are responsible for a large proportion of the violence is very striking, and researchers have found that across many different types of crimes and many different contexts,” she said.

The results showing who participated in the genocide may help prevent and de-escalate future conflicts, according to Nyseth Nzitatira. The information may help in development of targeted interventions for those more likely to engage in violence.

In addition, having these more accurate numbers of how many participated in the genocide is important for the country of Rwanda, Nyseth Nzitatira said.

“More accurate figures can help in the country’s rebuilding and healing, which continues today.”

Co-authors on the study were Laura Frizzell, a doctoral student in sociology at Ohio State, and Jared Edgerton of the Human Trafficking Data Lab at Stanford University, who is now an assistant professor at the University of Texas at Dallas.

The research was funded by the National Science Foundation.

JOURNAL

Journal of Peace Research

DOI

10.1177/00223433221075211 

METHOD OF RESEARCH

Data/statistical analysis

SUBJECT OF RESEARCH

People

ARTICLE TITLE

Analyzing Participation in the 1994 Genocide in Rwanda