Study examines current state regulations, public health risks of growing medicinal and recreational marijuana market

Peer-Reviewed Publication

ARIZONA STATE UNIVERSITY

 

IMAGE: A NEW STUDY URGES THAT STATE AND FEDERAL REGULATORS NEED TO TAKE A CLOSER LOOK AT HEALTH AND SAFETY RISKS OF THE GROWING MEDICINAL AND RECREATIONAL CANNABIS MARKET. view more 

CREDIT: NATIONAL INSTITUTE FOR DRUG ABUSE

A new study urges that state and federal regulators need to take a closer look at health and safety risks of the growing medicinal and recreational cannabis market.  

“Cannabis regulation is unlike any agricultural commodities, food, or drugs in the U.S. Currently, there are no national-level guidelines based on conventional risk assessment methodologies or knowledge of patients’ susceptibility in medical use of cannabis,” said lead author Max Leung, an Arizona State University assistant professor in the School of Mathematical and Natural Sciences.

“Therefore, our research team conducted the first comprehensive study to examine 3 main concerns: 1) the current landscape of state-level contaminant regulations, 2) identifying cannabis contaminants of concern in samples, and 3) explore any patient populations who may be susceptible to contaminants.”

The cannabis market has grown significantly in the past decade to become a $10 billion industry by 2017, $50 billion in 2026, and, within the past year, an estimated 55 million users. Currently, 15 states have made medicinal cannabis legal, but little attention has been paid to its implications in chemical exposure and consumer safety.

At the federal level, cannabis is still listed as an illegal substance. This limits the efforts of several federal agencies in assessing and mitigating the public health risk of cannabis contamination. Currently, cannabis is neither federally regulated as an agricultural, food, nor pharmaceutical commodity, so the USDA does not monitor its growth and FDA does not consider it a drug.

So, how is a cannabis user to know what they are putting into their bodies is safe? “There is surprisingly limited information on the contaminant level of cannabis products sold in this country,” said Leung.

Without any federal guidelines, it’s been left entirely up to the states to craft a patchwork of cannabis regulations and policy. “Individual legalized states and D.C. set their own rules with huge discrepancies,” said Leung.  

From their study, Leung and colleagues found that as of May 2022, 36 states and the District of Columbia have listed a total of 679 cannabis contaminants listed as regulated in medical or recreational cannabis. Most of these contaminants were pesticides (551, which included 174 insecticide, 160 herbicide and 123 fungicides subcategories), followed by solvents (74), microbes (21), inorganic compounds (12), mycotoxins (5) and 16 classified as “other.”

“What was interesting is that many pesticides in this document were highly unlikely to be utilized in cannabis cultivation and processing,” said Leung.  These pesticides included chlorpropham (a plant hormone that prevents potatoes from sprouting), oxytetracycline (an antibiotic), and norflurazon (an aquatic herbicide for Hydrilla control).

“What was also alarming to us is that the U.S. EPA tolerance document and individual jurisdictions also listed a total of 42 legacy pesticides that were no longer registered for any agricultural use in the U.S., such as dichlorodiphenyltrichloroethane (DDT), chlordane, lindane and parathion.”

As to the amount of contaminants levels, there were large inconsistencies from state to state. different state jurisdictions showed significant variations in regulated contaminants and action levels ranging up to four orders of magnitude.

How often was this a problem? The research team also mined data testing records of cannabis flower and extract samples produced in California, the largest state cannabis market in the U.S. Their sample data represented about 6% of California’s legal production in 2020-2021.

“As mandated by California’s Medicinal and Adult-Use Cannabis Regulation and Safety Act, all cannabis and cannabis products in the legal market of California are required to be tested for 68 pesticides, four inorganics, 20 solvents, six microbes, and five mycotoxins,” said Leung.

“The cannabis manufacturers must submit their products – including cannabis flowers and cannabis products such as edibles, concentrates, and other consumables – to a state-licensed cannabis testing laboratory. All products must be certified for compliance testing before they can be sold legally. The products that failed the state’s regulatory levels in the compliance testing are subject to recalls.”

The tallied an overall failure rate of 5.1% for the California cannabis samples, which included an average of the failure rate of 2.3% identified for flowers and 9.2% for extracts in California samples. Insecticides and fungicides were the most prevalent categories of detected contaminants, with boscalid and chlorpyrifos being the most common. The contaminant concentrations fell below the regulatory action levels in many legalized jurisdictions, indicating a higher risk of contaminant exposure.

Lastly, Leung’s team reviewed the medical cannabis use reports released by state-level public health agencies from 2016 to 2021.  Currently, there are 37 U.S. medical cannabis programs in and close to a hundred qualifying medical conditions listed by these programs. 

“Cannabis and cannabis products are often marketed as alternative options to standard medical treatments,” said Leung. “As such, medical cannabis can potentially expose susceptible patients to harmful contaminants.”

“Immunocompromised patients with cancer and HIV, women of reproductive age, and patients with seizures and epilepsy are among those who are more susceptible to the health hazards of pesticide and microbial contaminants that may be found in cannabis,” added Leung.  

The majority of patients were prescribed medical cannabis for use in alleviating pain (799,808 patients), followed by post-traumatic stress disorder (164,383 patients), spasticity associated with multiple sclerosis or spinal cord injury (78,145 patients), cancer (44,318 patients), and epilepsy (21,195 patients).

“Our findings have two important public health implications,” said Leung. “First, the scattershot approach of regulations at the state level can confuse cannabis manufacturers and discourage compliance while subjecting cannabis users to a higher level of contaminant exposure in some jurisdictions. Second, given the current status of cannabis contaminant regulation in the U.S., it is unclear whether the health benefit of cannabis usage outweighs the health risk of exposure to cannabis-borne contaminants.”

To help better inform the public and policy makers, Leung recommends further investigations to examine the safety considerations in susceptible patient populations across all medical conditions.

“The progression and prognosis of many qualifying conditions may be worsened by exposure to detected contaminants in cannabis,” said Leung. “This study demonstrates an urgent need for a unified regulatory approach to mitigate the public health risk of cannabis contamination at a national level.”

 

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JOURNAL

Environmental Health Perspectives

DOI

10.1289/EHP11206 

METHOD OF RESEARCH

Data/statistical analysis

SUBJECT OF RESEARCH

People

ARTICLE TITLE

Comparison of State-Level Regulations for Cannabis Contaminants and Implications for Public Health

ARTICLE PUBLICATION DATE

14-Sep-2022

Study suggests walnuts are bridge to better health as we age

Eating walnuts may reinforce positive health benefits including better diet quality and likelihood to be more active

Peer-Reviewed Publication

KETCHUM NEW YORK

 NEWS RELEASE 14-SEP-2022

Researchers who reviewed 20 years of diet history and 30 years of physical and clinical measurements have found participants who ate walnuts early on in life showed a greater likelihood for being more physically active, having a higher quality diet, and experiencing a better heart disease risk profile as they aged into middle adulthood.

These novel findings come from the Coronary Artery Risk Development in Young Adults Study (CARDIA),1 a long-term and ongoing study that is supported by the National Heart, Lung, and Blood Institute of the National Institutes of Health and aimed at examining the development of heart disease risk factors over time.

This study is one of the longest to suggest that the simple act of adding about a handful of heart-healthy^ walnuts into the diet often could act as a bridge to other health-promoting lifestyle habits later in life.

The findings also reinforce that walnuts might be an easy and accessible food choice to improve a variety of heart disease risk factors when eaten in young to middle adulthood.

In this recent study published in Nutrition, Metabolism, & Cardiovascular Diseases,2 University of Minnesota School of Public Health researchers note that a possible explanation for the results could be due to the unique combination of nutrients found in walnuts and their effect on health outcomes.

Walnuts are the only tree nut that is an excellent source of the plant-based omega-3 alpha-linolenic acid (2.5 grams/oz.), which research shows may play a role in heart health, brain health and healthy aging.^,3,4 Additionally, just one serving of walnuts (1 oz.), or about a handful, contains a variety of other important nutrients to support overall health including 4 grams of protein, 2 grams of fiber, and a good source of magnesium (45 milligrams). Walnuts also offer a variety of antioxidants, including polyphenols.

According to Professor of Epidemiology and Community Health at the University of Minnesota School of Public Health and Lead Researcher on CARDIA, Lyn M. Steffen, PhD, MPH, RD, “Walnut eaters seem to have a unique body phenotype that carries with it other positive impacts on health like better diet quality, especially when they start eating walnuts from young into middle adulthood – as risk of chronic diseases like heart disease, obesity, and diabetes elevates.”

Study Overview

In this observational, longitudinal study, partially supported by the California Walnut Commission, diet and health information was collected and analyzed from 3,023 otherwise healthy black and white men and women aged 18-30 at one of four field centers located in Birmingham, AL, Chicago, IL, Minneapolis, MN, and Oakland, CA, when the CARDIA study began in 1985-86. Self-reported diet history was taken at three times throughout the study: baseline, year seven, and year 20. Physical and clinical measurements were taken at multiple exams spanning 30 years.

Diet history was categorized into “walnut consumers,” “other nut consumers,” or “no nut consumers,” and assessed for relationships among heart disease risk factors, including dietary intake, smoking, body composition, blood pressure, plasma lipids (e.g., triglycerides), fasting blood glucose, and insulin concentrations in 352 walnut consumers, 2,494 other nut consumers, and 177 no nut consumers.

Average intake of walnuts during the study was about ¾ oz./day, and intake of nuts among other nut consumers was about 1 ½ oz./day.

“There was a good degree of diversity in terms of the research field locations geographically speaking and the population studied,” said Steffen. “Following these black and white women and men for 30 years provides an unparalleled window of study into how lifestyle decisions made in free-living environments in young adulthood can affect health in middle-age,” adds Steffen.

Study Results At A Glance

Overall, the researchers reported the following results:

• Physical and Clinical Indicators of Heart Disease Risk After 30 Years:
  • Walnut consumers had higher self-reported physical activity scores than other nut and no nut consumers.  
  • Compared to other nut consumers, eating walnuts was linked with a better heart disease risk profile:
    • Lower body mass index
    • Lower waist circumference
    • Lower blood pressure
    • Lower blood triglyceride levels
  • Eating walnuts was associated with less weight gain over the study period, and fewer participants who ate walnuts were classified as people with obesity compared to other nut and no nut consumers.
  • Compared to no nut consumers, walnut consumers had significantly lower fasting blood glucose concentrations while other nut consumers had higher LDL-cholesterol.
• Markers of Diet Quality After 20 Years:
  • Including walnuts in the diet during young adulthood was favorably linked with a higher total diet quality score (Healthy Eating Index 2015) when compared to other and no nut consumers.
  • Compared to other nut or no nut consumers, people who ate walnuts had the following self-reported daily dietary intakes, including a significant relationship with higher intakes of several under consumed nutrients and food groups of public health importance as outlined in the 2020-2025 Dietary Guidelines for Americans:5*

Higher (Unit)

Lower (Unit)

Polyunsaturated fat intake (%kcal) Gamma-linolenic acid (GLA) + Alpha-linolenic acid (ALA) intake (grams) Dietary fiber intake* (grams) Vitamin B6 intake (milligrams) Magnesium intake (milligrams) Vitamin E intake (milligrams) Potassium intake* (milligrams) Whole grains* (servings per day) Fruit* (servings per day) Vegetables* (servings per day) Legumes* (servings per day) Fish (servings per day) Protein sources (servings per day)

Saturated fat intake (% kcal) Added sugar intake (% kcal) Refined grain products (servings per day) Red meat (servings per day) Processed red meat (servings per day)

“Nut consumers showed an advantage in relation to diet quality, but walnut consumers appear to have a better heart disease risk factor profile than the other groups, even after accounting for overall diet quality,” said Steffen. “The surprising, healthy shifts in overall dietary pattern of walnut consumers suggests walnuts may act as a bridge or ‘carrier food’ for helping people form healthy nutrition and lifestyle habits throughout life.”

While these results are positive and confirm earlier work from the CARDIA study on the health benefits of walnut intake,1 randomized controlled clinical trials should be done in other populations and settings to confirm the observations in the current study. Observational studies cannot support cause and effect conclusions.

Additionally, some of the outcomes for heart disease risk factors relating to cholesterol and lipids in the current study are inconsistent with previous randomized controlled trials.6,7 This could be related to differences in study design, including duration of the intervention (e.g., several months to 30 years) or amount of nut intake. Last, the researchers did not isolate other specific nuts in their database, so findings cannot indicate no benefit of other nuts.

This study is one of the longest to suggest that adding about a handful of walnuts to the diet every day and early on in life could be linked with benefits to overall diet quality as a heart-healthy “carrier food” that fits into any eating occasion.  

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References:

1. Steffen LM, Yi SY, Duprez D, Zhou X, Shikany JM, Jacobs DR Jr. Walnut consumption and cardiac phenotypes: The Coronary Artery Risk Development in Young Adults (CARDIA) study. Nutr Metab Cardiovasc Dis. 2021;31(1):95-101.
2. Yi SY, et al. Association of nut consumption with CVD risk factors in young to middle-aged adults: The Coronary Artery Risk Development in Young Adults (CARDIA) study [published online ahead of print July 30, 2022]. Nutrition, Metabolism and Cardiovascular Diseases. doi:10.1016/j.numecd.2022.07.013.
3. Sala-Vila A, et al. Impact of α-linolenic acid, the vegetable ω-3 fatty acid, on cardiovascular disease and cognition [published online ahead of print February 16, 2022]. Advances in Nutrition. doi:10.1093/advances/nmac016.
4. Sala-Vila A, et al. Effect of a 2-year diet intervention with walnuts on cognitive decline. The Walnuts And Healthy Aging (WAHA) study: A randomized controlled trial. Am J Clin Nut. 2020;111(3):590–600.
5. U.S. Department of Agriculture and U.S. Department of Health and Human Services. Dietary Guidelines for Americans, 2020-2025. 9th Edition. December 2020. Available at DietaryGuidelines.gov.
6. Rajaram S, Cofán M, Sala-Vila A, et al. Effects of walnut consumption for 2 years on lipoprotein subclasses among healthy elders: findings from the WAHA Randomized Controlled Trial. Circulation. 2021;144(13):1083-1085.
7. Guasch-Ferré M, Li J, Hu FB, Salas-Salvadó J, Tobias DK. Effects of walnut consumption on blood lipids and other cardiovascular risk factors: an updated meta-analysis and systematic review of controlled trials. Am J Clin Nutr. 2018;108(1):174-187.

^Supportive but not conclusive research shows that eating 1.5 ounces of walnuts per day, as part of a low saturated fat and low cholesterol diet and not resulting in increased caloric intake, may reduce the risk of coronary heart disease. (FDA) One ounce of walnuts offers 18 grams of total fat, 2.5 grams of monounsaturated fat, 13 grams of polyunsaturated fat including 2.5 grams of alpha-linolenic acid – the plant-based omega-3.

About California Walnut Commission: 

The California Walnut Commission, established in 1987, is funded by mandatory assessments of the growers. The Commission is an agency of the State of California that works in concurrence with the Secretary of the California Department of Food and Agriculture (CDFA). The CWC is mainly involved in health research and export market development activities. For more industry information, health research and recipe ideas, visit www.walnuts.org.

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JOURNAL

Nutrition Metabolism and Cardiovascular Diseases

DOI

10.1016/j.numecd.2022.07.013 

METHOD OF RESEARCH

Observational study

SUBJECT OF RESEARCH

People

ARTICLE TITLE

Association of nut consumption with CVD risk factors in young to middle-aged adults: The Coronary Artery Risk Development in Young Adults (CARDIA) study

UK government delays less-healthy food regulations

Researchers claim delay is a step back in tackling obesity epidemic

Peer-Reviewed Publication

THE OBESITY SOCIETY

ROCKVILLE, Md.—Researchers argue that a delay by the UK Government to restrict promotions on foods High in Fat, Sugar and Salt (HFSS) this October is a “step back” in combating rising obesity levels, according to a new perspective in Obesity, The Obesity Society’s (TOS) flagship journal.

“The government's decision will delay the much-needed transformation of retail food environments and their promoted products, both of which are highly influential on what foods people buy and eat. The likely consequence is a huge set back in improving UK population diets, obesity levels and health,” said Sally Moore, PhD, RD, School of Food Science and Nutrition, University of Leeds, UK. Moore is the corresponding author of the perspective.

Besides restricting promotions on less-healthy food products, the planned approaches within the UK Childhood Obesity plan are additional regulations banning HFSS television advertising before 9 p.m. and paid for advertising online, both of which are facing similar delays. The youth referenced are those that the UK Government has described as “uniquely vulnerable to the techniques used to promote sales,” according to the perspective authors.

Researchers explain that the aim of the policies is to fundamentally change those retail food environments that are promoting less-healthy products and shift the balance towards healthier foods. The delayed regulations required scrutiny of each product’s nutritional composition to establish whether specific product types were permitted to be promoted or advertised. Restricted products are classified as HFSS according to their content of calories and certain nutrients of public health concern while recognizing contributions from components such as fruits and vegetables or fiber. The authors write in the perspective piece “without this regulation, commercial retail food environments will be difficult to change.”

A clear implication of the delay is that the anticipated reductions in population calorie intakes that were previously modeled on the policy implementation will now be far less than expected. The delays are also expected to worsen the growing inequalities in dietary quality and obesity levels that are associated with socioeconomic status.

As a result, the authors explain there is a concern that when rationalizing the delay, the UK Government cited the current unprecedented global economic situation. Rising costs of food and fuel is a concern for healthcare and nutrition professionals; as is the number of people at risk for food insecurity. “There is an urgent need to address this equitably and ethically by reducing socioeconomic disparities and levels of poverty,” the authors said.

The authors argue that the UK Government appears to have retreated to resolving the obesity epidemic with emphasis on individual willpower instead of the food industry. “Willpower alone cannot explain successful weight management,” said Tom Butler, PhD, Faculty of Health, Social Care and Medicine and the Cardiorespiratory Research Centre, Edge Hill University, Ormskirk, Lancashire, UK, a co-author of the study. Moore and Butler add that “delaying these polices will, yet again, leave public health and clinical practitioners tackling obesity with less-effective approaches focused on individual willpower and information provision.”

“The UK government’s adoption of restrictions on promotions of less-healthy foods as well as their advertising would have been a huge leap forward in nutrition-related public policy. Not only would the adoption of such a policy been in line with current scientific understanding, there is also significant public support in the UK for such policies. While individual willpower does indeed play a role in weight-related outcomes, providing a supportive environment plays a critical role in strengthening and fortifying individuals in their initial and sustained efforts to reach healthier weights and lifestyles. Policies that favor the uptake and promotion of high-energy, nutrient-poor foods can only serve to damage the general public’s health in the long run,” said Travis Masterson, PhD, MS, Broadhurst Career Development Professor for the Study of Health Promotion and Disease Prevention, The Pennsylvania State University. Masterson was not associated with the perspective piece.

The perspective, titled “UK Government Delays Restriction of Promotion on Less-healthy Foods: Serious Implications for Tackling Obesity”  can be found in the Wiley online library for Obesity.

Moore is the chair of the British Dietetic Association (BDA) Public Health Specialist Group pro bono. She has previously provided consultancy for the BDA's Corporate Strategic Partners, including UK food industry organizations. Butler is a committee member of the BDA Public Health Specialist Group and scientific officer for the British Association for Cardiovascular Prevention and Rehabilitation.
 

#  #  #

 

The Obesity Society (TOS) is the leading organization of scientists and health professionals devoted to understanding and reversing the epidemic of obesity and its adverse health, economic and societal effects. Combining the perspective of researchers, clinicians, policymakers and patients, TOS promotes innovative research, education and evidence-based clinical care to improve the health and well-being of all people with obesity. For more information, visit www.obesity.org

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COI STATEMENT

Sally Moore is the chair of the British Dietetic Association (BDA) Public Health Specialist Group pro bono. She has previously provided consultancy for the BDA's Corporate Strategic Partners, including UK food industry organizations. Tom Butler is a committee member of the BDA Public Health Specialist Group and scientific officer for the British Association for Cardiovascular Prevention and Rehabilitation.

What was left out of the founding myth of the green revolution?

Peer-Reviewed Publication

THE ALLIANCE OF BIOVERSITY INTERNATIONAL AND THE INTERNATIONAL CENTER FOR TROPICAL AGRICULTURE

 

IMAGE: ACCORDING TO A RECENT ANALYSIS, THE GREEN REVOLUTION NARRATIVE WAS BASED ON A MISINTERPRETATION OF A CASE STUDY IN GUATEMALA. view more 

CREDIT: ALLIANCE OF BIOVERSITY AND CIAT / MANON KONINGSTEIN

One of the founding narratives of the Green Revolution (a push towards technology-driven modernization of agriculture starting over 50 years ago) has been found to be false, according to a recent analysis by a researcher at the Alliance of Bioversity International and CIAT.

The Green Revolution is often credited with tripling production of staple crops while using only 30% more cultivated land in the latter half of the 20th century, largely through the use of technology like breeding higher yielding plant varieties and the application of pesticides and fertilizers. 

Policy thinkers paved the way for the Green Revolution and as part of his 1964 book, Transforming Traditional Agriculture, Nobel Prize-winning economist Ted Schultz told the story of Maya Kaqchikel farmers growing onions and other crops in the delta of a small river and the surrounding hills in Panajachel, Guatemala. He used this tale of a technologically-stagnant rural village fully embedded in a market economy to support his global vision of technology-centered agricultural development. For Schultz, this village was a well-documented example of a much wider trend in global agriculture.

This story, Jacob van Etten, Principal Scientist and Director of the Digital Inclusion research program at the Alliance of Bioversity International and CIAT, said, became the narrative basis of the Green Revolution, along with the population growth and food security aspects from Norman Borlaug, who  also helped to develop the dwarf strain of wheat that dramatically increased crop yields.

Van Etten said that by revisiting the history and context of the 1930s, it became clear that Schultz had “got the story wrong” and that new narratives about the Green Revolution should reserve a much more important place for institutional change in agricultural development. 

In his paper, Revisiting the adequacy of the economic policy narrative underpinning the Green Revolution, published in the journal Agriculture and Human Values, van Etten showed that Schultz deliberately tried to hide that the village’s Mayan farmers were not challenged in technological terms and were able to reach relatively high economic returns. 

“I hadn’t expected this… What I thought I would find would be that the story only represents one kind of experience in agriculture, but actually it's not even about this village, it's a story about Schultz’s version of the village that influenced the world,” van Etten said, “and it’s a wrong story.”

The researcher explained that Schultz presented a distorted narrative which painted a picture of a population held back by a lack of access to modern varieties and fertilizers.  

“What limited farms in that village wasn't technology, it was access to land, to markets, to credit,” van Etten said, adding that Schultz’s parable ignored ethnic tensions dominating market exchange, a main barrier for agricultural development. 

Lessons for the Future of Agricultural Research

In the paper, van Etten explained that Schultz told his own story rather than the narrative-as-lived of the farmers he portrayed and as a result, the Panajachel story neglected the institutional and ethnic reasons behind the farmers’ struggles harnessing technological change.

The reason why it matters, van Etten said, is that these founding myths continue to influence how researchers and the general public perceive the Green Revolution. 

“It helps to look back at history and look at the Green Revolution as a broad process of change that was not only about crop seeds and fertilizers,” he said, adding that for example, historian Kapil Subramanian found in a 2015 study that the Green Revolution’s impact on productivity in India did not only rely on improved varieties. 

There were also major infrastructural investments in rural electricity to power irrigation pumps, as well as strong government management of markets for inputs, credit and food grains. 

According to van Etten, agricultural development is not just about technology but about a mix of things, in which markets and other institutions play the most important part.

“Our founding myth might be wrong, but if it gained influence, it was because of human choices,” van Etten said, “These choices become enshrined in the way we run research organizations, but we can take a new course in defining the goals of where we should go next.”

In addition, van Etten said that much of the work of CGIAR is already correcting old technology-centric thinking. 

“We take a critical look at the delivery of new technologies, gender and inequality aspects, and look beyond technologies to policies and institutions,” van Etten said, “Being aware about our own history helps to remove blinkers.” 

Another lesson was that in Panajachel, far from stagnation, there was a traditional knowledge base that was innovative in its own way. 

“A lot of innovation was happening... The local varieties are not just the result of 10,000 years of slow work and in Panajachel, farmers got seeds from all over the place and tried them on their farms,” van Etten said.

As agricultural research moves into a new phase, van Etten said, it's important to give farmers and their communities more agency to mix new technological solutions with their local knowledge. 

“Agricultural research can tap into local inventiveness and amplify it and Schultz was wrong in painting farmers as helpless and stagnant,” van Etten said.

“But Shultz was right in claiming that agricultural research is a good public investment and it can further accelerate farmer innovation, as we need all hands on deck to deal with current challenges, such as climate change.”

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Read the full article: Revisiting the adequacy of the economic policy narrative underpinning the Green Revolution

 

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JOURNAL

Agriculture and Human Values

DOI

10.1007/s10460-022-10325-2 

METHOD OF RESEARCH

Commentary/editorial

ARTICLE TITLE

Revisiting the adequacy of the economic policy narrative underpinning the Green Revolution

Conifer communication is complex and can be altered by air pollution

Peer-Reviewed Publication

UNIVERSITY OF EASTERN FINLAND

 

IMAGE: A LARGE PINE WEEVIL FEEDING ON SCOTS PINE. view more 

CREDIT: COPYRIGHT JARMO HOLOPAINEN. THE PHOTO MAY BE USED IN CONNECTION WITH THIS PRESS RELEASE ONLY.

Conifers are dominant tree species in boreal forests, but they are susceptible to attack by bark beetles. A new study from the University of Eastern Finland shows that upon attack by bark-feeding weevils, conifers release substantial quantities of volatile organic compounds that provide important cues to neighbouring seedlings.

It has long been known that when plants are damaged, they release odorous chemicals into the atmosphere. These chemicals represent an important medium through which plants communicate.
 
“Whereas broadleaved plants have been frequently shown to respond to chemical odours, the same observations have not been seen in conifers. Therefore, we decided to look whether conifers undergo a similar response and were amazed at the results,” Doctoral Researcher Hao Yu of the University of Eastern Finland says. 

The study showed that Scots pine seedlings damaged by bark-feeding weevils release vast quantities of volatile chemicals into the atmosphere. Undamaged plants exposed to these chemicals also start to release volatiles and prepare themselves to emit more if they are subsequently attacked by weevils.

Importantly, those receiver plants also increased their stomatal conductance and net photosynthesis rate.

“This observation is novel and has broad implications for further research investigating the mechanisms of how plants obtain information from their neighbours,” says Professor James Blande, leader of an Academy of Finland funded project on conifer communication at the University of Eastern Finland.

In addition, receiver plants had altered resin duct traits, and were subject to reduced amounts of damage by pine weevils.

The team also investigated the responses of receiver plants under elevated ozone conditions, which represents the situation in more polluted regions. They found that the responses were significantly altered, but the final defence outcome was not affected.

“The different responses of receiver plants made us think that the communication process was eliminated, but receiver plants still had more resistance to weevils,” Yu points out. 

This research sheds new light on the dynamism of conifer communication and shows that the process can be substantially altered by air pollution.

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JOURNAL

Proceedings of the Royal Society B Biological Sciences

DOI

10.1098/rspb.2022.0963 

ARTICLE TITLE

Volatile-mediated between-plant communication in Scots pine and the effects of elevated ozone.

Study quantifies impact of human activity on Atlantic Rainforest’s carbon storage capacity

Conservation of CO2 stocks in the biome is highly affected by forest degradation, which could lead to at least 30% higher emissions than those produced by climate change.

Peer-Reviewed Publication

FUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE SÃO PAULO

 

IMAGE: EXAMPLE OF HUMAN IMPACT ON ATLANTIC RAINFOREST: SELECTIVE LOGGING view more 

CREDIT: RENATO AUGUSTO FERREIRA DE LIMA

The countless benefits of native forests include the capacity of tree biomass to store large amounts of carbon, which can counterbalance greenhouse gas emissions into the atmosphere. A paper published in the journal Science Advances reports on an innovative analysis of a large dataset designed to clarify the concept of carbon sequestration, a strategic issue in the discussion of global climate change.

“We still know little about the factors that can lead forests to store more or less carbon,” said Renato Augusto Ferreira de Lima, one of the paper’s ten authors. Lima is affiliated with the Ecology Department at the University of São Paulo's Institute of Biosciences (IB-USP) in Brazil and is currently a researcher at the Center for Biodiversity Synthesis and Analysis (CESAB) in Montpellier (France). 

“We used a large forest inventory database to see which factors are uppermost in explaining current levels of carbon storage in the Atlantic Rainforest. We found that factors relating to the different types of human impact on the forest are key, with two to six times the significance of factors such as climate, soil and the characteristics of the tree species in the forest,” he said.

Reversing the effects of human activity on Atlantic Rainforest remnants would therefore be the best strategy to increase forest carbon stocks. About 50% of the Brazilian population currently live in areas originally occupied by the biome.

According to Marcela Venelli Pyles, first author of the paper and a PhD candidate in applied ecology affiliated with the Ecology and Conservation Department of the Federal University of Lavras (UFLA) in Minas Gerais, Brazil, conservation of carbon stocks in the Atlantic Rainforest is highly dependent on forest degradation, which can lead to carbon losses that are at least 30% worse than any future climate change. Moreover, emissions from forest degradation can hinder conservation efforts pledged in climate change mitigation agreements, such as REDD+ and the Aichi targets. 

REDD stands for “Reducing Emissions from Deforestation and forest Degradation”. The plus sign in REDD+ refers to “the role of conservation, sustainable management of forests and enhancement of forest carbon stocks in developing countries”, according to the UN Framework Convention on Climate Change, which adopted this mechanism to reward developing countries financially for climate change mitigation. 

The Aichi Biodiversity Targets were 20 global targets for biodiversity loss reduction to be met by 2020, agreed at the Tenth Conference of the Parties to the UN Convention on Biological Diversity (CBD), held in Nagoya, Aichi Prefecture, Japan, in 2010.

For example, tree damage and mortality due to disturbances in Atlantic Rainforest fragments resulting from canopy opening and microclimate changes can lead to carbon losses of up to 10.50 metric tons per hectare, corresponding to emission of 15.24% of the carbon stored in 1 hectare, while carbon storage protection and enhancement can achieve gains of 12.02 tons per hectare, increasing storage by 17.44%.

Warmer climate

Besides degradation due to human activity, the study also analyzed how climate change, particularly rising temperatures and water stress, endangers carbon storage by the Atlantic Rainforest. If global warming is limited to 1.5 °C above pre-industrial levels, as suggested by the Intergovernmental Panel on Climate Change (IPCC), the Atlantic Rainforest alone will release 3.53 tons per hectare (+ 5.12%). “But if the average temperature continues to rise at the current rate, carbon emissions could exceed 9.03 tons per hectare [+ 13.11%],” Pyles said.

The paper also argues that climate change mitigation actions involving forest restoration could benefit from the inclusion of species with higher wood density, heavier seeds and larger leaves, and that carbon conservation policy should take into account methodologies used to quantify carbon stocks. “The difference between methodologies used in the field can lead to errors in estimating carbon, entailing misinterpretation and inefficient climate change mitigation measures,” Pyles said.

The paper also notes a “weak relationship” between taxonomic and functional diversity and carbon storage in the Atlantic Rainforest. From this, it infers that conservation policies focusing only on carbon may fail to protect biodiversity and that separate incentive mechanisms to conserve species should be considered. 

According to Lima, the findings on the Atlantic Rainforest offer potential lessons for other forests around the world in terms of nature-based solutions to combat the adverse effects of climate change and human activity.

The paper is also signed by Luiz Fernando Silva Magnago (Federal University of Southern Bahia), Bruno X. Pinho (Federal University of Pernambuco), Gregory Pitta (USP), André L. De Gasper and Alexander C. Vibrans (Regional University of Blumenau), and Vinícius Andrade Maia, Rubens Manoel dos Santos and Eduardo van den Berg (UFLA). The study was supported by FAPESP, which funded Lima’s postdoctoral research.

About São Paulo Research Foundation (FAPESP)

The São Paulo Research Foundation (FAPESP) is a public institution with the mission of supporting scientific research in all fields of knowledge by awarding scholarships, fellowships and grants to investigators linked with higher education and research institutions in the State of São Paulo, Brazil. FAPESP is aware that the very best research can only be done by working with the best researchers internationally. Therefore, it has established partnerships with funding agencies, higher education, private companies, and research organizations in other countries known for the quality of their research and has been encouraging scientists funded by its grants to further develop their international collaboration. You can learn more about FAPESP at www.fapesp.br/en and visit FAPESP news agency at www.agencia.fapesp.br/en to keep updated with the latest scientific breakthroughs FAPESP helps achieve through its many programs, awards and research centers. You may also subscribe to FAPESP news agency at http://agencia.fapesp.br/subscribe

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JOURNAL

Science Advances

DOI

10.1126/sciadv.abl7968 

ARTICLE TITLE

Human impacts as the main driver of tropical forest carbon

Significant increase in suicide rates in women and younger age groups during the COVID-19 pandemic in Japan

Peer-Reviewed Publication

HOKKAIDO UNIVERSIT

 

IMAGE: THE OBSERVED RATE OF SUICIDES IN JAPAN BETWEEN JANUARY 2016 AND DECEMBER 2021 (DASHED LINE) FOR MALES (A) AND FEMALES (B). THE BLUE LINE INDICATES THE PRE-PANDEMIC TREND, WHILE THE RED LINE INDICATES THE PANDEMIC TREND (EIJI YOSHIOKA, SHARON J.B. HANLEY, YUKIHIRO SATO, YASUAKI SAIJO. THE LANCET REGIONAL HEALTH - WESTERN PACIFIC. MAY 30, 2022) view more 

CREDIT: EIJI YOSHIOKA, SHARON J.B. HANLEY, YUKIHIRO SATO, YASUAKI SAIJO. THE LANCET REGIONAL HEALTH - WESTERN PACIFIC. MAY 30, 2022

An estimated 1208 excess suicide deaths for men and 1825 for women were recorded during the COVID-19 Pandemic in Japan through December 2021, with the impact being greatest in women and younger age groups.

Studies have shown that death by suicide can increase during infectious disease epidemics. While increased community cohesion and mutual support may have initially decreased suicide risk during the COVID-19 pandemic, few studies have been conducted on the long-term impact of the COVID-19 pandemic in Japan.

A joint study by researchers at Hokkaido University and Asahikawa Medical University has analysed trends in monthly suicide rates by age and gender from January 2016 to December 2021 in Japan using provisional mortality data in an interrupted time series analysis.

The group found that there were 1208 excess suicide deaths for men and 1825 for women between April 2020 and December 2021. While there was no statistically significant increase in overall suicide rates for men and women during the pandemic period, sub-group analyses revealed that there was a statistically significant increase in men aged 20 – 29 years and 40 – 49 years, and in women 20 – 29 years, 30 – 39 years, 50 – 59yrs, 60 - 69 years and 70 – 79 years.

“Our results show that the COVID-19 pandemic has had a negative impact on trends in suicide rates in Japan, specifically in women and in younger age groups,” said Dr. Sharon Hanley, one of the study co-authors. “This indicates that governments and other agencies need to identify and provide appropriate additional support to socio-economically vulnerable subgroups of the population during the pandemic.”

Associate Professor Eiji Yoshioka who led the study stressed, “since the COVID-19 pandemic is still evolving, continued vigilance and close monitoring of suicide mortality rates as well as the mental health of the population remains a priority”.

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JOURNAL

The Lancet Regional Health - Western Pacific

DOI

10.1016/j.lanwpc.2022.100480 

METHOD OF RESEARCH

Data/statistical analysis

SUBJECT OF RESEARCH

Not applicable

ARTICLE TITLE

Impact of the COVID-19 pandemic on suicide rates in Japan through December 2021: An interrupted time series analysis