Breaking News
November 14, 2018 - Study shows novel strategy to reduce breast cancer bone metastasis
November 14, 2018 - Empowering the NHS through Industry Partnerships
November 14, 2018 - One size does not fit all in obesity treatment, study finds
November 14, 2018 - Seeking ways to prevent ‘secondary cataracts’
November 14, 2018 - Change Within the Eye May Be Early Warning for Macular Degeneration
November 14, 2018 - Study of 500,000 people clarifies the risks of obesity
November 14, 2018 - Ultrasound releases drug to alter activity in targeted brain areas in rats | News Center
November 14, 2018 - Umass Amherst researchers battle against youth suicide in rural Alaska Native communities
November 14, 2018 - Cancer stem cells depend on amino acid metabolism, and it’s proving to be their Achilles’ heel
November 14, 2018 - Epigenetic link found between prenatal exposure to maternal smoking and offspring’s cardio-metabolic health
November 14, 2018 - Meditation, music may change biomarkers of cellular aging and Alzheimer’s disease in older adults
November 14, 2018 - Multidisciplinaryresearch teams selected to study age-related brain disorders
November 14, 2018 - The Current issue of “The view from here” is concerned with Informatics
November 14, 2018 - Researchers identify tool to help transgender women have a more authentic voice
November 14, 2018 - Four faculty members appointed to endowed professorships | News Center
November 13, 2018 - Research finds strongest evidence yet that obesity causes depression
November 13, 2018 - Researchers compare stools of breastfed and formula-fed infants
November 13, 2018 - Entasis Therapeutics Announces Zoliflodacin Phase 2 Results Published in The New England Journal of Medicine
November 13, 2018 - Gene changes driving myopia reveal new focus for drug development
November 13, 2018 - $6 million grant to support study of preeclampsia, atherosclerosis links | News Center
November 13, 2018 - Beneficial gut microbes metabolize high-fiber diet to improve heart health in mouse model
November 13, 2018 - Excessive use of social media through visual postings linked to increase in narcissistic traits
November 13, 2018 - Study finds why obesity both fuels cancer growth and helps immunotherapy to kill tumors
November 13, 2018 - Women prefer and invest more in daughters, while men favor sons
November 13, 2018 - With hospitalization losing favor, judges order outpatient mental health treatment
November 13, 2018 - Transgenic rat model may provide new insights into cerebral amyloid angiopathy
November 13, 2018 - Study identifies factors tied to greater risk of advanced liver disease in cystic fibrosis patients
November 13, 2018 - Risk of blindness among premature babies with low levels of blood platelets
November 13, 2018 - A new strategy for combatting antibiotic-resistant infections
November 13, 2018 - Study aims to find which outreach method is more effective at improving cancer screening rates
November 13, 2018 - Insufficient sleep duration linked with unhealthy lifestyle profile among children
November 13, 2018 - IIASA researchers introduce new, simple measure for human wellbeing
November 13, 2018 - Magnetic nanosprings used as targeted drug delivery agents for anticancer therapy
November 13, 2018 - Scientists examine FCMs containing silver nanoparticles
November 13, 2018 - Failed DNA repair triggers chromosomal chaos
November 13, 2018 - Study shows new emerging role of osteopontin in HCV-related hepatocellular carcinoma
November 13, 2018 - Food insecurity during pregnancy linked to severity of neonatal abstinence syndrome
November 13, 2018 - Majority of Americans are concerned about health threat posed by antibiotic resistance
November 13, 2018 - Addition of Elotuzumab Ups PFS in Refractory Multiple Myeloma
November 13, 2018 - Study finds women with pregnancy-related nausea, vomiting use marijuana more
November 13, 2018 - Lethal heart rhythm more likely to be found in patients with common heart failure
November 13, 2018 - Study provides new clues to origin and development of multiple sclerosis
November 13, 2018 - Climate change could pose threat to male fertility
November 13, 2018 - Researchers discover how mitochondria deploy a powerful punch against disease-causing bacteria
November 13, 2018 - AHA: Traumatic Childhood Could Increase Heart Disease Risk in Adulthood
November 13, 2018 - Feeling the Burn? | NIH News in Health
November 13, 2018 - Women’s birth canals in Kenya, Korea, Kansas not the same: study
November 13, 2018 - Fecal microbiota transplantation effective against ICI-associated colitis
November 13, 2018 - New physical activity guidelines released that urge people to “move more”
November 13, 2018 - Angiotensin receptor blockers improve sodium excretion in blacks
November 13, 2018 - New project seeks to address alarming injury rate in youth footballers
November 13, 2018 - Fish oil or omega 3 fatty acid supplements can prevent heart attacks finds study
November 13, 2018 - The Human Heart-in-a-Jar That Could One Day Replace Animal Testing
November 13, 2018 - Treat patients’ partners without a doctor visit
November 13, 2018 - Belgian beer landscape mapped using scientific insights
November 13, 2018 - ‘Master key’ gene has links to both ASD and schizophrenia
November 13, 2018 - Gladstone scientists gain new insights into the aging brain
November 13, 2018 - Drug therapy can improve outcomes for acutely ill heart patients
November 13, 2018 - Three landmark studies provide better understanding of sudden cardiac arrest
November 13, 2018 - Cholesterol control revised in the latest AHA/ACC guidelines
November 13, 2018 - Vulnerable young teenagers urgently need better sex education, say researchers
November 13, 2018 - Breakthrough research reveals how deadly pneumococcus avoids immune defenses
November 13, 2018 - Researchers discover possible path forward in preventing cancers tied to two viruses
November 13, 2018 - Wishes can help pediatric patients to get better over time
November 13, 2018 - Janssen Reports Positive Topline Results for FLAIR Phase 3 Study of a Novel, Long Acting Injectable Two-Drug Regimen for the treatment of HIV-1
November 13, 2018 - Experimental compound reduces Gulf War illness-like behavior in mice
November 13, 2018 - Small-stature in rainforest populations may be linked to cardiac adaptations
November 13, 2018 - Study shows how pneumococci challenge the immune system
November 13, 2018 - Simple cysts can be safely ignored, study finds
November 13, 2018 - First fully personalized tissue implant engineered from patient’s own materials and cells
November 13, 2018 - FDA Approves Keytruda (pembrolizumab) in Combination with Carboplatin and Either Paclitaxel or Nab-Paclitaxel for the First-Line Treatment of Patients with Metastatic Squamous Non-Small Cell Lung Cancer (NSCLC)
November 13, 2018 - Scientists take big step toward finding non-addictive painkiller
November 13, 2018 - Diabetes medication reduces risk of heart failure hospitalization
November 13, 2018 - Achieving high follow-up rates for violently injured patient population is feasible
November 13, 2018 - Shortage of specific gene ‘silencing’ molecules linked with pediatric low-grade gliomas
November 13, 2018 - Abx-Resistant Enterobacteriaceae Tied to Clinical Failure in UTI
November 13, 2018 - US approves first new type of flu drug in 2 decades
November 13, 2018 - Is zinc the link to how we think? Some evidence, and a word of warning
November 13, 2018 - Dispelling taboos, Michelle Obama talks IVF and miscarriage
November 13, 2018 - Medical experts discuss future challenges of healthcare at HSMA’s inaugural conference
Study highlights global and local impacts of delayed mercury-controlling policies

Study highlights global and local impacts of delayed mercury-controlling policies

image_pdfDownload PDFimage_print

Mercury is an incredibly stubborn toxin. Once it is emitted from the smokestacks of coal-fired power plants, among other sources, the gas can drift through the atmosphere for up to a year before settling into oceans and lakes. It can then accumulate in fish as toxic methylmercury, and eventually harm the people who consume the fish.

What’s more, mercury that was previously emitted can actually re-enter the atmosphere through evaporation. These “legacy emissions” can drift and be deposited elsewhere, setting off a cycle in which a growing pool of toxic mercury can circulate and contaminate the environment for decades or even centuries.

A new MIT study finds that the longer countries wait to reduce mercury emissions, the more legacy emissions will accumulate in the environment, and the less effective any emissions-reducing policies will be when they are eventually implemented.

In a paper published in the journal Environmental Science and Technology, researchers have found that, for every five years that countries delay in cutting mercury emissions, the impact of any policy measures will be reduced by 14 percent on average. In other words, for every five years that countries wait to reduce mercury emissions, they will have to implement policies that are 14 percent more stringent in order to meet the same reduction goals.

The researchers also found that remote regions are likely to suffer most from any delay in mercury controls. Mercury contamination in these regions will only increase, mostly from the buildup of legacy emissions that have traveled there and continue to cycle through and contaminate their environments.

“The overall message is that we need to take action quickly,” says study author Noelle Selin, associate professor in MIT’s Institute for Data Systems and Society and Department of Earth, Atmospheric, and Planetary Sciences. “We will be dealing with mercury for a long time, but we could be dealing with a lot more of it the longer we delay controls.”

Global delay

The Minamata Convention, an international treaty with 101 parties including the United States, went into effect in August 2017. The treaty represents a global commitment to protect human health and the environment by reducing emissions of mercury from anthropogenic sources. The treaty requires that countries control emissions from specific sources, such as coal-fired power plants, which account for about a quarter of the world’s mercury emissions. Other sources addressed by the treaty include mercury used in artisanal and small-scale gold mining, nonferrous metals production, and cement production.

In drafting and evaluating their emissions-reducing plans, policymakers typically use models to simulate the amount of mercury that would remain in the atmosphere if certain measures were taken to reduce emissions at their source. But Selin says many of these models either do not account for legacy emissions or they assume that these emissions are constant from year to year. These measures also do not take effect immediately — the treaty urges that countries take action as soon as possible, but its requirements for controlling existing sources such as coal-fired power plants allow for up to a 10-year delay.

“What many models usually don’t take into account is that anthropogenic emissions are feeding future legacy emissions,” Selin says. “So today’s anthropogenic emissions are tomorrow’s legacy emissions.”

The researchers suspected that, if countries hold off on implementing their emissions control plans, this could result in the growth of not just primary emissions from smokestacks, but also legacy emissions that made it back into the atmosphere a second time.

“In real life, when countries say, ‘we want to reduce emissions,’ it usually takes many years before they actually do,” says Hélène Angot, the study’s first author and a former postdoc at MIT. “We wanted to ask, what are the consequences of delaying action when you take legacy emissions into account.”

The legacy of waiting

The group used a combination of two models: GEOS-Chem, a global atmospheric model developed at MIT that simulates the transport of chemicals in the atmosphere around the world; and a biogeochemical cycle model that simulates the way mercury circulates in compartments representing global atmosphere, soil, and water.

With this modeling combination, the researchers estimated the amount of legacy emissions that would be produced in any region of the world, given various emissions-reducing policy timelines. They assumed a scenario in which countries would adopt a policy to reduce global mercury emissions by 50 percent compared to 2010 levels. They then simulated the amount of mercury that would be deposited in lakes and oceans, both from primary and legacy emissions, if such a policy were delayed every five years, from 2020 to 2050.

In sum, they found that if countries were to delay by five, 10, or 15 years, any policy they would implement would have 14, 28, or 42 percent less of an impact, respectively, than if that same policy were put in place immediately.

“The longer we wait, the longer it will take to get to safe levels of contamination,” Angot says.

Remote consequences

Based on their simulations, the researchers compared four regions located at various distances from anthropogenic sources: remote areas of eastern Maine; Ahmedabad, one of the largest cities in India, located near two coal-fired power plants; Shanghai, China’s biggest city, which has elevated atmospheric mercury concentrations; and an area of the Southern Pacific known for its tuna fisheries.

They found that, proportionally, delays in mercury action had higher consequences in the regions that were farthest away from any anthropogenic source of mercury, such as eastern Maine — an area that is home to several Native American tribes whose livelihoods and culture depend in part on the local fish catches.

Selin and Angot have been collaborating with members of these tribes, in a partnership that was established by MIT’s Center for Environmental Health Sciences.

“These communities are trying to go back to a more traditional way of life, and they want to eat more fish, but they’re contaminated,” Angot says. “So they asked us, ‘When can we safely eat as much fish as we want? When can we assume that mercury concentrations will be low enough so we can eat fish regularly?'”

To answer these questions, the team modeled the amount of fish contamination in eastern Maine that could arise from a buildup of legacy emissions if mercury-reducing policies are delayed. The researchers used a simple lake model, adapted and applied at MIT in collaboration with colleagues at Michigan Technological University, that simulates the way mercury circulates through a column that represents layers of the atmosphere, a lake, and the sediment beneath. The model also simulates the way mercury converts into methylmercury, its more toxic form that can bioaccumulate in fish.

“In general, we found that the longer we wait to decrease global emissions, the longer it will take to get to safe methylmercury concentrations in fish,” Angot says. “Basically, if you are far away [from any anthropogenic source of mercury], you rely on everyone else. All countries have to decrease emissions if you want to see a decrease in contamination in a very remote place. So that’s why we need global action.”

Source:

http://news.mit.edu/2018/study-mercury-controlling-policies-impact-1101

Tagged with:

About author

Related Articles