Dental crowding: Ancient baleen whales had a mouthful

CT scans of a 25 million year-old fossil skull show the Aetiocetus weltoni had both teeth and baleen, unlike modern whales

SAN DIEGO STATE UNIVERSITY

3D digital reconstruction of Aetiocetus weltoni skull.

CREDIT: ERIC EKDALE, SAN DIEGO STATE UNIVERSITY

A strange phenomenon happens with modern blue whales, humpback whales and gray whales: they have teeth in the womb but are born toothless. Replacing the teeth is baleen, a series of plates composed of thin, hair- and fingernail-like structures growing from the roof of their mouths that act as a sieve for filter feeding small fish and tiny shrimp-like krill.

The disappearing embryonic teeth are testament to an evolutionary history from ancient whales that had teeth and consumed larger prey. Modern baleen whales on the other hand use their fringed baleen to strain their miniscule prey from water, hence the term filter feeding.

A new study that utilized high-resolution computed tomography (CT) to scan a 25 million year-old fossil whale skull found neurovascular evidence that Aetiocetus weltoni, an evolutionary "cousin" of today's baleen whales (Mysticeti), had both teeth and baleen simultaneously in adulthood, making for a very crowded mouth.

The Oligocene age mysticete fossil was discovered along the coast of Oregon by graduate students with the Museum of Paleontology at the University of California, Berkeley, and loaned to biologist and lead author Eric Ekdale with San Diego State University and paleontologist Thomas Deméré with the San Diego Natural History Museum for the study.

Since baleen decomposes and is rarely preserved intact in fossils, the scientists relied on digital reconstructions with CT imaging to search for evidence of baleen in Aetiocetus. The study revealed grooves and holes on the roof of the mouth that connect internally with a vascular canal in a fashion consistent with the pattern of blood vessels that lead to baleen in modern mysticetes.

What that demonstrates is that the blood supply for the teeth was co-opted for a new function, to support the growth of baleen in living baleen whales, the authors said.

The study also revealed separate connections between the major internal canal and smaller canals that would have delivered blood to the upper teeth, which is consistent with the pattern of blood supply to teeth in living toothed whales such as sperm whales and killer whales, porpoises, dolphins, and terrestrial mammals.

"We have found evidence that supports a co-occurrence of teeth and baleen, indicating the tooth-to-baleen transition occurred in a stepwise manner from just teeth, to teeth and baleen, to only baleen," Ekdale said.

Shift in food habits

"Our study provides tangible fossil evidence of a major shift in feeding behavior from a raptorial carnivorous feeding mode to a bulk filter-feeding mode for obtaining food, among the largest animals that have ever lived in earth's oceans," Ekdale said. "Krill are around 1/600th the size of blue whales. That's like us humans eating nothing larger than sesame seeds floating in a pool."

The four main living groups of baleen whales each pursue different diets and use their baleen filter in different ways, so they divide up ocean resources rather than compete with each other for the same prey.

The study will be published with open access May 24 in the Zoological Journal of the Linnean Society, part of the Oxford University Press family of journals.

Anatomical distinction

In the case of Aetiocetus, which was less than half the size of a living gray whale, what puzzles some researchers in the field is how the whale managed to process its food, if it had both baleen and teeth, since the baleen might get in the way of teeth in the mastication process. However, the position of the holes observed in Aetiocetus suggests that the baleen was not in the "line of fire" and unlikely to result in interference between the teeth and baleen.

The study establishes that "while the tiny holes on the palate of Aetiocetus may look similar at a superficial level to other mammals, we can clearly demonstrate that this anatomy is related to baleen in baleen whales," Deméré said.

Ancestors of whales evolved for hundreds of millions of years, first on land as terrestrial mammals, and began their invasion of the sea around 53 million years ago. It's this transition and the subsequent diversification of fully aquatic whales that fascinates Ekdale and Deméré, and discoveries such as theirs indicate how remarkable is the history of life on our planet.

CAPTION

Artist's reconstruction of Aetiocetus weltoni, a 25 million year old baleen whale, with teeth and baleen. Co-occurrence of teeth and baleen side-by-side allow the animal to eat single prey, such as small fish, with their teeth, as well as large accumulations of small crustaceans with their baleen.

CREDIT

Art by C. Buell, used with permission from J. Gatesy.

Impact of school nutrition policies in California varies by children's ethnicity

US SCHOOLS DELIVER SOCIAL WELFARE

EDUCATION NOT SO MUCH

PLOS

Research News

 

California state school nutrition policies and federal policies for school meals have mixed impacts on childhood obesity in children of Pacific Islander (PI), Filipino (FI) and American Indian/Alaska native (AIAN) origins, according to a new study published this week in the open access journal PLOS Medicine by Mika Matsuzaki of Johns Hopkins Bloomberg School of Public Health, USA, and colleagues.

Children of PI, FI and AIAN origin are some of the most understudied subgroups experiencing high rates of overweight/obesity. California has enacted policies on foods and beverages available in schools through a series of standards beginning in 2004, and federal policies in 2010 also sought to improve school nutrition standards. In the new study, researchers used data on demographics, body composition and fitness that were collected by the California Department of Education on students in 5th and 7th grade each year between 2002 and 2016 as part of the state Physical Fitness Testing program.

Overall, the prevalence of overweight/obesity was higher among PI (39.5-52.5%), FI (32.9-36.7%), and AIAN (37.7-45.6%) children in comparison to White (26.8-30.2%) students. During the baseline period of the study, the overweight/obesity prevalence increased among nearly all students, with the steepest increases for PI and AIAN students. After California state policies went into effect, from 2002 to 2004, the overweight/obesity rates decreased for almost all groups, with the largest fall seen among PI girls in 5th grade (before: log odds ratio = 0.149 (95%CI 0.108 to 0.189; p<0.001); after: 0.010 (-0.005 to 0.025; 0.178)). When both the California and federal nutrition policies were in effect, after 2010, additional declines in the overweight/obesity prevalence were seen among White and FI students but not for PI or AIAN students. As the study was only conducted in California, without a comparison group unaffected by the policies, the researchers could not establish that all changes in prevalence of overweight/obesity were solely attributable to the policies.

"There remain wide racial/ethnic disparities between these racial/ethnic minority subgroups and their White peers," the authors say. "Additional strategies are needed to reduce childhood obesity and related disparities among these understudied racial/ethnic populations."

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Research Article

Peer reviewed; Observational study; Humans

In your coverage please use this URL to provide access to the freely available paper:

http://journals.plos.org/plosmedicine/article?id=10.1371/journal.pmed.1003596

Funding: The study was supported by the Robert Wood Johnson Foundation (https://www.rwjf.org/ 74375, ESV), the National Heart, Lung, and Blood Institute of the National Institutes of Health (https://www.nhlbi.nih.gov/ K01HL115471 and 1R01HL136718, ESV; and R01-HL131610 and P01ES022844 BNS). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.

Competing Interests: The authors have declared that no competing interests exist.

Citation: Matsuzaki M, Sánchez BN, Rebanal RD, Gittelsohn J, Sanchez-Vaznaugh EV (2021) California and federal school nutrition policies and obesity among children of Pacific Islander, American Indian/Alaska Native, and Filipino origins: Interrupted time series analysis. PLoS Med 18(5): e1003596. https://doi.org/10.1371/journal.pmed.1003596

PRIVATIZED HEALTHCARE

Study finds health insurance disruptions associated with worse healthcare access

AMERICAN CANCER SOCIETY

Research News

 

ATLANTA - MAY 24, 2021 - A new study underscores the importance of health insurance coverage continuity in access to and receipt of care and care affordability in the United States. Researchers found that health insurance coverage disruptions were consistently associated with worse healthcare access and problems with care affordability. The study appears in the American Journal of Preventive Medicine.

Decades of research has demonstrated that health insurance coverage is associated with better access to care and health outcomes in the U.S. However, less research has addressed coverage disruptions (i.e., periods without insurance) among adults with current coverage and the relationship of disruptions with care access, receipt of recommended preventive services, and affordability. To learn more, investigators led by Robin Yabroff, PhD, MBA of the American Cancer Society conducted a comprehensive examination of insurance coverage disruptions among adults aged 18 to 64 years from the 2011-2018 National Health Interview Survey using multiple measures of access and affordability, and evaluated the effects of the duration of coverage disruption among currently insured and uninsured.

The study found that prior disruptions in insurance coverage were relatively common among adults aged 18-64 years in the U.S. Among currently insured adults, 5.0% with private insurance and 10.7% with public insurance reported a coverage disruption in the prior year, representing nearly 9.1 million adults in 2018. Among currently uninsured adults, 24.9% reported coverage loss within the prior year, representing nearly 8.1 million adults in 2018. Compared to adults with continuous health insurance coverage, adults with coverage disruptions were less likely to receive recommended preventive services and more likely to forgo any needed care because of cost and report medication non-adherence because of cost.

Longer coverage disruptions were associated with worse care access and affordability. The magnitude of associations between coverage disruptions and care access and affordability was similar among adults with either current private or current public coverage. Currently uninsured adults, especially with longer uninsured periods, reported significantly worse care access, receipt, and affordability than currently insured adults with coverage disruptions or continuous coverage.

"Our findings highlight the importance of health insurance coverage continuity related to access to care and affordability. This is especially relevant with recent increases in unemployment due to the COVID-19 pandemic and widespread loss of employer-based private coverage, the primary source of private coverage in the working-age population," said the authors.

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Article: Yabroff R, Zhao, J, Halpern M, Fedewa S, Han X, Nogueira L, Zheng Z, Jemal A. Health insurance disruptions and care access and affordability in the US. AJPM: American Journal of Preventive Medicine, 2021. doi: 10.1016/j.amepre.2021.02.014.

URL upon embargo: https://www.ajpmonline.org/article/S0749-3797(21)00178-1/fulltext

Babies with seizures may be overmedicated

Study suggests that keeping newborns on longer term antiseizure medication may not prevent continued seizures or epilepsy or change development.

MICHIGAN MEDICINE - UNIVERSITY OF MICHIGAN

Research News

 

ANN ARBOR, Mich. - Newborns who experience seizures after birth are at risk of developing long term chronic conditions, such as developmental delays, cerebral palsy or epilepsy.

Which is why all of these babies receive medication to treat the electrical brain disturbances right away.

While some babies only receive antiseizure medicine for a few days at the hospital, others are sent home with antiseizure medicine for months longer out of concern that seizures may reoccur.

But according to a new multicenter study, continuing this treatment after the neonatal seizures stop may not be necessary.

Babies who stayed on antiseizure medications after going home weren't any less likely to develop epilepsy or to have developmental delays than those who discontinued the medicines before leaving hospital, suggest findings in JAMA Neurology.

"There is wide variability in how different hospitals and physicians manage care for newborns with seizures," says senior author Renée Shellhaas, M.D., M.S., pediatric neurologist at University of Michigan C.S. Mott Children's Hospital.

Although neonatal seizures usually resolve within 72 hours, longer term medication is often prescribed out of caution, according to co-principal investigator and lead author for the study, Hannah C. Glass, MDCM, MAS.

"Our findings suggest that staying on antiseizure medication after leaving the hospital doesn't protect babies from continued seizures or prevent epilepsy and it does not change developmental outcomes," says Glass, a pediatric neurologist at the University of California, San Francisco Benioff Children's Hospital.

The study involved about 300 babies born at nine different centers over a three-year period who all developed seizures in their first days to weeks after birth. Two-thirds of babies stayed on medication after discharge from the hospital - averaging four months of treatment. But a third had antiseizure medicine discontinued before they went home - after just a few days of treatment.

Thirteen percent of babies developed epilepsy but there were no associations with medication duration.

Overmedication risks

Among the biggest concerns for longer term use of antiseizure medicine is that it may expose babies to potentially neurotoxic effects, which research indicates may be associated with lower cognitive scores.

The most commonly used medication for neonatal seizures is phenobarbital, which slows down brain activity but causes sedation.

Newborns who are prescribed this kind of medication for seizures may also have more trouble waking up to feed and engaging in other types of activities important to growth and development.

"We really need to balance the risks of continued medication with benefits to babies' health," Shellhaas says. "If it's not necessary, then keeping them on medicine could do more harm than good."

"Most of the babies in this study went home on antiseizure medications, which suggests we need to re-think standard practice," adds Glass. "We've never had such robust data from multiple centers to support this type of change for newborns with seizures."

Previous small, single-center studies have also suggested that early discontinuation of antiseizure medication isn't harmful.

More than 16,000 newborns in the U.S. experience neonatal seizures each year, with nearly half developing long-term health problems, according to nonprofit organization PCORI, which supported the new study.

Shellhaas, Glass and their colleagues will continue to follow this cohort of infants up to school age to assess development, including sensory processing, IQ and potential learning disabilities through research supported by the National Institutes of Health.

"We want to continue to track these children to watch for any subtle differences that may emerge over time," Shellhaas says.

"We hope this research will help drive decisions about caring for newborns with seizures and help us improve their outcomes over the course of their lives."

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Study Cited: "'Safety of Early Discontinuation of Antiseizure Medication After Acute Symptomatic Neonatal Seizures," JAMA Neurology, Doi:10.1001/jamaneurol.2021.1437.

 

MALE Infertility poses major threat to biodiversity during climate change, study warns

UNIVERSITY OF LIVERPOOL

Research News

 

A new study by University of Liverpool ecologists warns that heat-induced male infertility will see some species succumb to the effects of climate change earlier than thought.

Currently, scientists are trying to predict where species will be lost due to climate change so they can plan effective conservation strategies. However, research on temperature tolerance has generally focused on the temperatures that are lethal to organisms, rather than the temperatures at which organisms can no longer breed.

Published in Nature Climate Change, the study of 43 fruit fly (Drosophila) species showed that in almost half of the species, males became sterile at lower than lethal temperatures. Importantly, the worldwide distribution of these species could be predicted much more accurately by including the temperature at which they become sterile, rather than just using their lethal temperature. To give an example, Drosophila lummei males are sterile four degrees below their lethal limit. To put that in context, four degrees is the temperature difference between summer in northern England and the south of France.

Dr Steven Parratt, lead researcher from the University of Liverpool, said: "Our findings strongly suggest that where species can survive in nature is determined by the temperature at which males become sterile, not the lethal temperature.

"Unfortunately, we do not have any way to tell which organisms are fertile up to their lethal temperature, and which will be sterilised at cooler temperatures. So, a lot of species may have a hidden vulnerability to high temperatures that has gone unnoticed. This will make conservation more difficult, as we may be overestimating how well many species will do as the planet warms."

The researchers went on to model this for one of the Drosophila species using temperature predictions for 2060 and found more than half of areas with temperatures cool enough to survive will be too hot for the males to remain fertile.

Dr Tom Price, senior researcher from the University of Liverpool, commented: "Our work emphasises that temperature-driven fertility losses may be a major threat to biodiversity during climate change. We already had reports of fertility losses at high temperature in everything from pigs to ostriches, to fish, flowers, bees, and even humans. Unfortunately, our research suggests they are not isolated cases, and perhaps half of all species will be vulnerable to thermal infertility.

"We now urgently need to understand the range of organisms likely to suffer thermal fertility losses in nature, and the traits that predict vulnerability. We must understand the underlying genetics and physiology, so we can predict which organisms are vulnerable, and perhaps produce breeds of livestock more robust to these challenges."

Head of Terrestrial Ecosystems at the Natural Environment Research Council Dr Simon Kerley said: "This is a highly exciting piece of work that turns on its head our thinking and assumption of the role, rate, and impact of climate change. It really starts to shed light on the hidden and subtle impact of the changing conditions on the myriad of animals that we perhaps take for granted and have not previously considered 'at risk' from our changing climate. Importantly, it alerts us to the understanding this risk could occur sooner than we thought.

"This piece of work takes biology, at its most fundamental level, and explores it in a well-known and understood laboratory animal, but then takes that crucial extra step of relating it to the real world and the potential impact if may have on global biodiversity.

"With the COP15 and COP26 conferences taking place this year, this study serves as a timely reminder of the need to research and better understand the relationship between climate change and biodiversity loss. The Natural Environmental Research Council will continue to fund this vital research, and UKRI as a whole will work as part of the global effort to safeguard the natural environment for generations to come."

The study involved collaborators from the University of Leeds, University of Melbourne, University of Zürich and Stockholm University and was funded by the UK Natural Environment Research Council (NERC).

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 ANCIENT KNOWLEDGE REVIVED

Storytelling reduces pain and stress, and increases oxytocin in hospitalized children

New research shows robust evidence that telling stories can increase the quality of life of children in ICUs

D'OR INSTITUTE FOR RESEARCH AND EDUCATION

Research News

 

A new research, carried out by the D'Or Institute for Research and Education (IDOR) and the Federal University of ABC (UFABC), has shown for the first time that storytelling is capable of providing physiological and emotional benefits to children in Intensive Care Units (ICUs). The study was published in the Proceedings of the National Academy of Sciences, the official scientific journal of the National Academy of Sciences of the U.S. The study was led by Guilherme Brockington, PhD, from UFABC, and Jorge Moll, MD, PhD, from IDOR.

"During storytelling, something happens that we call 'narrative transportation'. The child, through fantasy, can experience sensations and thoughts that transport him or her to another world, a place that is different from the hospital room and is, therefore, far from the aversive conditions of hospitalization", affirms Guilherme Brockington, PhD, and lead author of the study.

Storytelling is an immemorial practice of humanity. Legends, religions, and social values have spanned millennia through orality and writing. The most current best-selling cinematographic scripts and novels captivate the audiences through the same mechanism: listening to a good story is moving from one reality to another. This movement, driven by imagination, can create empathy for events and characters that fluctuate according to the interpretation of each individual.

"Until now, the positive evidence for storytelling was based on 'common sense' and taken at face value, in which interacting with the child may distract, entertain and alleviate psychological suffering. But there was a lack of a solid scientific basis, especially with regard to underlying physiological mechanisms", explains Dr. Moll.

Considering the psychological and biological processes that occur during, and after listening to a story, the study investigators came up with the idea of seeking scientific evidence for the effects of storytelling on critically hospitalized children.

In total, 81 children were selected, aged between 2 and 7 years and with similar clinical conditions, such as respiratory problems caused by asthma, bronchitis, or pneumonia. The children were admitted to the ICU at Rede D'Or São Luiz Jabaquara Hospital, in São Paulo, Brazil, and were randomly divided into two groups: 41 of them participated in a group in which storytellers read children's stories for 25 to 30 minutes, while in a control group, 40 children were told riddles offered by the same professionals and during the same length of time.

To compare the effects of the two interventions, saliva samples were collected from each participant before and after each session to analyze the oscillations of cortisol and oxytocin - hormones related to stress and empathy, respectively. In addition, the children took a subjective test to evaluate the level of pain they were feeling before and after participating in the activities. They also performed a free word association task by relating their impressions about 7 cards illustrated with elements from the hospital context (Nurse, Doctor, Hospital, Medicine, Patient, Pain, and Book).

The outcomes were positive for all groups, as both interventions reduced the level of cortisol and increased the production of oxytocin in all the children analyzed, while the sensation of pain and discomfort was also mitigated, according to the evaluation of the children themselves. However, a significant difference was that the positive results of the children in the storytelling group were twice as good as those in the riddles group. These findings led the researchers to conclude that the narrative activity was substantially more effective.

"Another highlight of this study is that it was not performed in an artificial environment, but rather within the routine of the pediatric ICU. The storytelling was done individually; the child chose which story would be told. Among the books offered, we chose titles available in ordinary bookstores and without a pre-defined emotional bias, so that the story would not influence the child's reaction so much after the activity", highlights Dr. Brockington.

Even though storytelling was already being adopted in many children's hospitals, this is the first time we are presented with robust evidence of its physiological and psychological impacts. This contributes to seeing the activity as an effective and low-cost therapeutic method, which can make a great difference in the quality of life for children in intensive care units.

"I consider this study to be one of the most important I have participated in, due to its simplicity, rigor, and potential direct impact on practices in the hospital environment, aiming at the relief of human suffering. As it is a low-cost and highly safe intervention, it can potentially be implemented in the entire public system, once larger-scale studies verify its reproducibility and effectiveness. We intend to extend and replicate it in other settings and patient groups and to support volunteering dedicated to the noble activity of storytelling, now with more solid scientific evidence ", points out Dr. Moll.

The emotional impacts of storytelling were also revealed in the results of the free word association test, done at the end of each intervention. Children in the storytelling group reported more positive emotions than in the control group, when exposed to the Hospital, Nurse, and Doctor words. For example, the children in the control group responded to the card with the drawing of a Hospital saying: "this is the place that people go when they are sick". Children in the storytelling group reported for the same card as: "this is the place that people go to get better". 

For the illustrations of a nurse and a doctor, the same pattern was observed. Children in the control group remarked "This is the bad woman who comes to give me an injection", while those who were told the stories said phrases such as: "This is the woman who comes to heal me".

Although the research had the support of trained volunteer storytellers from the Brazilian non-profit association "Viva e Deixe Viver", the authors state that storytelling is an activity that can be equally practiced by parents and educators, thus providing space for children to participate in the choice of the book and to interact with the story. In addition to reducing anxiety and stress, the activity enables the strengthening of bonds between the child, the narrator, and the other people present in the environment.

The authors also remarked that the findings of this research on storytelling point to additional potential applications for children experiencing environmental stress, such as the disruption caused by the pandemic. Storytelling by parents, relatives and friends may be a simple and effective way to improve the wellbeing of a child and is accessible to all families.

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About the D'Or Institute for Research and Education

Founded in 2010, the D'Or Institute for Research and Education (IDOR) is a non-profit organization that aims to promote scientific advancement, qualification, dissemination of knowledge, and innovation in Healthcare. IDOR develops studies aimed at both applied science, that is, with direct clinical impact in the short term, as well as fundamental science, which seeks deeper knowledge about biological, physiological, and pathological mechanisms. The importance of bringing basic and clinic science closer together was evidenced in research involving the Zika virus, in which IDOR researchers played a key role in proving the relationship between the virus and microcephaly. The results had a wide international reach and were published in Science, one of the most prestigious scientific journals worldwide.

About Viva e Deixe Viver

It is a private non-profit entity, created in August 1997, and is formed by volunteers - mostly storytellers - who provide their service free of charge. Through the art of storytelling, the Association forms citizens aware of the importance of welcoming and acceptance, producing well-being based on human values such as empathy, ethics, and affection. Viva e Deixe Viver gathers more than a thousand active volunteers and is present in hospitals in São Paulo and other states and cities in Brazil.

Trends and Characteristics of Manufactured Cannabis Product and Cannabis Plant Product Exposures Reported to US Poison Control Centers, 2017-2019

Julia A. Dilley, PhD¹; Janessa M. Graves, PhD²; Ashley Brooks-Russell, PhD³; et alJennifer M. Whitehill, PhD⁴; Erica L. Liebelt, MD^5,6

Author Affiliations Article Information

JAMA Netw Open. 2021;4(5):e2110925. doi:10.1001/jamanetworkopen.2021.10925

 May 24, 2021

Introduction

Legalization of adult use cannabis products has led to a consumer-driven marketplace. A growing share of retail cannabis sales are manufactured cannabis products,¹ which may contain higher levels of tetrahydrocannabinol (THC) than unprocessed cannabis plant materials,² resulting in greater short-term effects (eg, cognitive and psychomotor impairment).³ Public health concerns are emerging about these risks.⁴ Our study objective was to assess recent patterns in reports of cannabis-related exposures by product type.

Methods

For this cross-sectional study, we accessed National Poison Data System data on cannabis exposures reported to US poison centers for January 2017 through December 2019. Cannabis product type codes were added to the system in 2016. We compared trends and characteristics of exposures for manufactured products that require processing of plant materials (eg, concentrates, edibles, vaporized liquids) and unprocessed plant materials (eg, flower) (eMethods in the Supplement). Two-sided P values <.05 were considered statistically significant. This study followed the Strengthening the Reporting of Observational Studies in Epidemiology (STROBE) reporting guideline for cross-sectional studies. The institutional review board at Washington State University determined this study was exempt from review because it used deidentified data.

Results

Among the total 28 630 exposures, plant materials were the most commonly involved (18 763 exposures [65.5%]), followed by edibles (5537 [19.3%]), concentrates (2734 [9.6%]), vaporized liquids (1075 [3.8%]), and other manufactured products (521 [1.8%]) (Table).

Manufactured product exposure cases more often involved children: 2505 cases (27.0%) involved patients under 10 years old, compared with 1490 plant-based exposures (8.4%). Exposures to edibles had the greatest proportion of children (1905 exposures [36.6%]). More than half of all calls were made from a health care facility; manufactured product calls came from a residence nearly twice as often as plant-based exposure calls (3927 [39.8%] vs 3817 [20.3%]; P < .001).

Most manufactured cannabis product exposures were for those products alone (8040 exposures [81.5%]). In contrast, most plant exposures (11 556 [61.6%]) also involved other agents (eg, alcohol, other drugs). Among exposures where only cannabis was involved, a slightly smaller percentage of manufactured product exposures overall (2918 [36.3%]) were associated with serious medical outcomes compared with plant-based exposures (2803 [38.9%]). Vaporized liquid exposures were most likely to have serious medical outcomes (268 [42.3%]).

During 2019, population-based rates for manufactured cannabis product exposures overall and for most specific products were greater where adult cannabis use was legal. One exception was vaping: exposure calls per 100 000 population were 0.29 in nonlegal states (692 total exposures) and 0.21 in legal states (195 total exposures).

Total cannabis exposures increased between 2017 and 2019. However, quarterly plant-related exposure reports declined over time, while manufactured product exposure reports increased overall and for each specific product (Figure).

Discussion

Our findings document that US poison centers are increasingly receiving calls about adverse events associated with exposures to manufactured cannabis products. Higher rates in legal states suggest that continued increases may be expected with adult cannabis use legalization in more states.

Children may be at particular risk for exposure to edible products, such as cookies or candy. Although we did not see more serious health outcomes for manufactured product exposures compared with plant products overall, most cannabis plant exposures involved polysubstance use, whereas most cases for manufactured products were for those products alone, suggesting that exposure to manufactured products alone may be relatively more likely to generate adverse events. This is consistent with studies of acute health effects.³

Manufactured products may present risks both because of THC levels and other processing ingredients. For example, vaporized liquid additive ingredients were implicated in a 2019 national lung injury (e-cigarette or vaping use–associated lung injury [EVALI]) outbreak.⁵

Market factors may drive the industry to continue developing novel products, which could present additional health risks. Applying regulatory controls to market-driven innovations in potency and additives is key. Novice cannabis users are often advised to “start low, go slow”; this guidance may be equally applicable to regulating new retail cannabis markets and products.

This study was limited by its data source. Poison centers provide useful information about specific product exposures and medical outcomes; however, data are self-reported and may underestimate the burden of cases. Ongoing monitoring of manufactured product–specific adverse events is recommended to understand public health concerns and effectiveness of regulations or harm reduction messaging.

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Article Information

Accepted for Publication: March 30, 2021.

Published: May 24, 2021. doi:10.1001/jamanetworkopen.2021.10925

Open Access: This is an open access article distributed under the terms of the CC-BY License. © 2021 Dilley JA et al. JAMA Network Open.

Corresponding Author: Julia A. Dilley, PhD, Program Design and Evaluation Services, Public Health Division, Oregon Health Authority, 800 NE Oregon St, Ste 260, Portland, OR 97232 (julia.dilley@multco.us).

Author Contributions: Dr Dilley had full access to all of the data in the study and takes responsibility for the integrity of the data and the accuracy of the data analysis.

Concept and design: Dilley, Graves, Brooks-Russell, Whitehill.

Acquisition, analysis, or interpretation of data: Dilley, Graves, Whitehill, Liebelt.

Drafting of the manuscript: Dilley.

Critical revision of the manuscript for important intellectual content: All authors.

Statistical analysis: Dilley.

Obtained funding: Graves.

Administrative, technical, or material support: Dilley, Graves, Liebelt.

Supervision: Graves, Liebelt.

Conflict of Interest Disclosures: Dr Graves reported receiving grants from the Alcohol and Drug Abuse Research Program at Washington State University; she reported serving on the board of directors for the Washington Poison Center outside the submitted work. Dr Whitehill reported receiving consulting fees from Washington State University during the conduct of the study. Dr Liebelt reported receiving consulting fees from Washington State University during the conduct of the study and a grant given her organization (Washington Poison Center) from Verdant Health Commission to develop curriculum and education on harmful effects of cannabis. No other disclosures were reported.

Funding/Support: This investigation was supported in part by funds provided for medical and biological research by the State of Washington (initiative measure No 171). Support for Dr Dilley was provided in part by the National Institute on Drug Abuse of the National Institutes of Health (award No 1R01DA039293).

Role of the Funder/Sponsor: The funder had no role in the design and conduct of the study; collection, management, analysis, and interpretation of the data; preparation, review, or approval of the manuscript; and decision to submit the manuscript for publication.

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Smart  R, Caulkins  JP, Kilmer  B, Davenport  S, Midgette  G.  Variation in cannabis potency and prices in a newly legal market: evidence from 30 million cannabis sales in Washington state.   Addiction. 2017;112(12):2167-2177. doi:10.1111/add.13886PubMedGoogle ScholarCrossref

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BROADCAST AROUND WIND TURBINES

Experimental broadcast of whitewater river noise drives bats and birds away

Intense noise reduces bird foraging activity and causes bats to switch hunting strategies

CALIFORNIA POLYTECHNIC STATE UNIVERSITY

Research News

 

IMAGE: DR. DYLAN GOMES LED THE TEAM THAT DEPLOYED SPEAKER ARRAYS EARLY IN THE SPRING TO BEGIN PLAYBACK OF WHITEWATER RIVER NOISE BEFORE MOST BIRDS AND BATS WERE USING THIS HIGH... view more 

CREDIT: DR. CORY TOTH

While many might consider a walk in the woods to be a quiet, peaceful escape from their noisy urban life, we often don't consider just how incredibly noisy some natural environments can be. Although we use soothing natural sounds in our daily lives - to relax or for meditation - the thunder of a mountain river or the crash of pounding surf have likely been changing how animals communicate and where they live for eons. A new experimental study published in the journal Nature Communications finds that birds and bats often avoid habitat swamped with loud whitewater river noise.

Dr. Dylan Gomes, a recent PhD graduate of Boise State University and first author on the paper, summarizes the aims of the work this way, "naturally-loud environments have been largely neglected in ecological research. We aimed to test the hypothesis that intense natural noise can shape animal distributions and behavior by experimentally broadcasting whitewater river noise at a massive scale." In fact, the scientists had to transport literal tons of gear across roadless terrain to place solar-powered speaker arrays in half of their 60 locations in the Pioneer Mountains of Idaho where they monitored bird and bat populations for two summers.

The speaker arrays were arranged along riparian areas, filling each bubbling brook with the auditory experience of a rushing whitewater river. The team took advantage of their experimental approach to broadcast both realistic reproductions of river noise, as well as river noise that had been shifted upwards in frequency to understand how the noise caused changes in animal numbers. "The prevailing hypothesis for why many animals avoid noise is called masking. Masking occurs when noise overlaps in frequency (what we perceive as pitch) with a biological signal or cue. By broadcasting noise of different frequencies, we hoped to assess the role that masking of important sounds, such as birdsong, plays in the avoidance of noisy places", said the senior author of the study, Dr. Jesse Barber of Boise State University. The scientists found that overlap between background noise and song frequency predicted bird declines until acoustic environments became about as loud as a highway, at which point other forces, such as an inability to hear predators and prey, likely become more important.

Understanding how noise drives animals out of otherwise good habitat is clearly important, but what about the animals that stay behind? To study foraging in birds that remained in naturally-loud places the authors set out hundreds of caterpillar decoys made of clay across their study sites. By carefully examining the types of marks predators left in the clay, the scientists found that more noise meant less foraging by birds. This means that, even after controlling for the fact that fewer birds were found in loud places, birds were less efficient at visually hunting for these silent, decoy caterpillars in the presence of noise. This is not unlike the difficulty people can experience when trying to listen to a friend talk while a muted television is on, dividing our attention.

To understand how bats that remained in noise-exposed areas fared, the team deployed two foraging puzzles to solve. The first was a "robo-moth" that lured in bats with its insect-like wing beats. The second was a speaker playing a "mix tape" of cricket and katydid calls and insect walking sounds. After almost 150 nights of data collection the scientists found that, as the world gets louder, some bats switch from listening for prey sounds to using echolocation. Dr. Gomes explains, "this behavioral switch is likely driven by prey calls and footsteps being masked by river noise and this type of problem-solving likely explains why some bats can remain near the ruckus of a raging whitewater river".

When putting all these pieces together, the authors argue that by studying how animals respond to noise sources that they have faced throughout their evolutionary history, we can get a better handle on how animals will deal with human-caused noise. Dr. Clinton Francis from California Polytechnic State University and Co-Principal Investigator of the study says, "our work showing that natural noise can structure where animals live and how they behave only increases the call to manage human-caused noise. The spatial and temporal footprint of anthropogenic noise is far greater than loud natural environments."

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Other co-authors on this paper include Dr. Cory Toth, a former postdoctoral researcher and Hunter Cole, a current Master's student, both members of the Barber Lab at Boise State University. This work was funded by the National Science Foundation and was conducted on land owned and managed by Lava Lake Ranch.