Breaking News
March 22, 2019 - TMJ disorders could be treated with tissue-engineered implants after successful animal study
March 22, 2019 - Team-based approach is key to successful care of pregnant women with heart failure
March 22, 2019 - Study identifies gene variant associated with accelerated cellular aging
March 21, 2019 - Salk scientists show how background noise from neurons can interrupt focused attention
March 21, 2019 - New class of drugs could help treat patients diagnosed with ovarian cancer
March 21, 2019 - Tecentriq Approved for Small Cell Lung Cancer
March 21, 2019 - Adipocyte glucocorticoid receptors play a role in developing steroid diabetes
March 21, 2019 - Climate change can affect nutrient content of crops, harming human health
March 21, 2019 - Podcast: KHN’s ‘What The Health’ Surprise! Fixing Surprise Medical Bills Is Harder Than it Looks
March 21, 2019 - Chemistry researchers patent new method for making anti-leukemia compounds
March 21, 2019 - UIC scientists identify hidden proteins in bacteria
March 21, 2019 - New Australian drug trial achieves remarkable results in patients with acute myeloid leukemia
March 21, 2019 - Females live longer when they have help raising offspring
March 21, 2019 - How did orthodontists sell orthodontics?
March 21, 2019 - In the Spotlight: From dietitian to physician assistant student
March 21, 2019 - The CRISPR Revolution: What You Need to Know
March 21, 2019 - FDA Chief Calls For Stricter Scrutiny Of Electronic Health Records
March 21, 2019 - Combined glucocorticoid and antioxidant therapy could benefit premature babies
March 21, 2019 - Low levels of certain eye proteins could serve as predictor for Alzheimer’s
March 21, 2019 - Post-traumatic holocaust survivors transmit negative views on aging to offspring
March 21, 2019 - City of Hope receives $7.5 million in grant awards to study cutaneous T cell lymphoma
March 21, 2019 - New video game-led training device helps stroke survivors regain arm mobility
March 21, 2019 - Compounds in coffee could slow prostate cancer growth
March 21, 2019 - New mobile DNA element in Wolbachia may contribute to improved disease control strategies
March 21, 2019 - Phase 2 Clinical Trial of Bermekimab Shows Potential New Standard of Care for Treatment of Hidradenitis Suppurativa, Including Significant Pain Reduction without Antibiotics
March 21, 2019 - More than one-third of patients risk major bleeding by doubling up on blood thinners
March 21, 2019 - A skeptical look at popular diets: Thumbs up for Mediterranean
March 21, 2019 - PTSD After Cardiac Arrest Predicts More Heart Trouble
March 21, 2019 - Role of immunological imprinting in elicitation of new antibodies
March 21, 2019 - Breast cancer relapse predictor tool may soon be a reality
March 21, 2019 - New computer program developed by TGen lights up cancer-causing genetic mutations
March 21, 2019 - FDA warns two breast implant makers for failure to comply with post-approval study requirements
March 21, 2019 - Butler Hospital receives COBRE grant to enhance research on neuropsychiatric illnesses
March 21, 2019 - Majority of osteoporosis clinical practice guidelines ignore patients’ voices
March 21, 2019 - Generic messages don’t help patients to lose weight
March 21, 2019 - Eisai and Imbrium Therapeutics Announce U.S. FDA Filing Acceptance of New Drug Application for Lemborexant for the Treatment of Insomnia
March 21, 2019 - Two-drug combos using popular calcium channel blocker show superiority in lowering BP
March 21, 2019 - First-in-human pilot study shows positive results for ‘bacteria-phobic’ catheter
March 21, 2019 - Itamar Medical launches next-generation WatchPAT system for home sleep apnea testing
March 21, 2019 - Study estimates health and economic impacts of healthy food prescriptions
March 21, 2019 - Detecting fungal disease in crops with multispectral imaging system
March 21, 2019 - MIT announces creation of the Alana Down Syndrome Center
March 21, 2019 - Next-generation LVAD device clinically superior, safer for heart failure patients
March 21, 2019 - Allergan Announces FDA Approval of Avycaz (ceftazidime and avibactam) for Pediatric Patients
March 21, 2019 - Mutations in noncoding genes could play big role in regulating cancer, study finds
March 21, 2019 - A medical student’s thoughts on Match Day
March 21, 2019 - Are eggs good or bad for you?
March 21, 2019 - New analysis reveals precision oncology insights for colorectal cancer
March 21, 2019 - Pollutants appear to weaken immune system and increase pathogen virulence
March 21, 2019 - Researchers develop and validate scale for rating severity of mononucleosis
March 21, 2019 - Scientists identify generation of key immune response in mice on introducing solid food
March 21, 2019 - New nanomaterial could restore internal structure of damaged bones
March 21, 2019 - Selective destruction of prostate tumor as effective as complete prostate removal
March 21, 2019 - 2011 to 2015 Saw Increase in Psychiatric ED Visits for Youth
March 21, 2019 - Tapeworm drug targets common vulnerability in tumor cells
March 21, 2019 - WVU researcher discovers higher suicide rate among Medicaid-insured youth
March 21, 2019 - Off the beaten path for global health residency
March 21, 2019 - European Parliament’s report calls on EU to develop policies to regulate endocrine-disrupting chemicals
March 21, 2019 - Women with undiagnosed diabetes in pregnancy more likely to experience stillbirths
March 21, 2019 - Fish consumption can help prevent asthma, study reveals
March 21, 2019 - Royal Holloway professors to lead new to research into curing Neurofibromatosis type 1
March 21, 2019 - NSF offers grant to improve treatment approaches for pelvic organ prolapse
March 21, 2019 - Your Apple Watch Might Help Spot a Dangerous Irregular Heartbeat
March 21, 2019 - Research team uncovers critical new clues about what goes awry in autistic brains
March 21, 2019 - From March Madness to medicine with help from mentors
March 21, 2019 - Mental health disorders among young adults may be on the increase
March 21, 2019 - New study examines smarter automatic defibrillator
March 21, 2019 - UC Riverside research shows how natural selection favors cheaters
March 21, 2019 - Mother’s diet during pregnancy can impact lung-specific genes of her offspring
March 21, 2019 - AeroForm Tissue Expanders makes breast reconstruction after mastectomy more comfortable
March 21, 2019 - New project focuses on creating more responsive, intuitive prosthetics
March 21, 2019 - New case study describes adolescent patient with rapid-onset schizophrenia and Bartonella infection
March 21, 2019 - Umass Amherst food scientist honored with 2019 Young Scientist Research Award
March 21, 2019 - Smell of skin could lead to early diagnosis for Parkinson’s
March 21, 2019 - Difference in brain connectivity may explain autism spectrum disorder
March 21, 2019 - Untangling the microbiome — with statistics
March 21, 2019 - Human microbiome metabolites enhance colon injury by enterohemorrhagic E. coli, study shows
March 21, 2019 - Written media can improve citizens’ understanding of palliative care
March 21, 2019 - New research aims to find how asthma symptoms are aggravated
March 21, 2019 - New $9.7 million NIH grant project seeks to improve hearing restoration
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