Living near or downwind of unconventional oil and gas development is linked with an increased risk of early death

Elderly people living near or downwind of unconventional oil and gas development (UOGD)—which involves extraction methods including directional (non-vertical) drilling and hydraulic fracturing, or fracking—are at higher risk of early death compared with elderly individuals who don’t live near such operations, according to a large new study from Harvard T.H. Chan School of Public Health.

Just off Interstate Highway 25, Drill Rig 1548 – Encana Natural Gas, works closely with their fracking drill rig in front of homes in the town of Frederick in Weld County, Colorado. Pipes, vehicles and storage tanks also stand in front of homes as hazy, snow-capped front range of the Rocky Mountains stand in the background.

The results suggest that airborne contaminants emitted by UOGD and transported downwind are contributing to increased mortality, the researchers wrote.

“Although UOGD is a major industrial activity in the U.S., very little is known about its public health impacts. Our study is the first to link mortality to UOGD-related air pollutant exposures,” said Petros Koutrakis, professor of environmental sciences and senior author of the study. Added co-author Francesca Dominici, Clarence James Gamble Professor of Biostatistics, Population, and Data Science, “There is an urgent need to understand the causal link between living near or downwind of UOGD and adverse health effects.”

UOGD has expanded rapidly over the past decade. As of 2015, according to the study, more than 100,000 UOGD land-based wells were drilled using directional drilling combined with fracking. Roughly 17.6 million U.S. residents currently live within one kilometer of at least one active well. Compared with conventional oil and gas drilling, UOGD generally involves longer construction periods and larger well pads (the area occupied by equipment or facilities) and requires larger volumes of water, proppants (sand or other materials used to keep hydraulic fractures open), and chemicals during the fracking process.

Prior studies have found connections between UOGD activities and increased human exposure to harmful substances in both air and water, as well as connections between UOGD exposure and adverse prenatal, respiratory, cardiovascular, and carcinogenic health outcomes. But little was known about whether exposure to UOGD was associated with mortality risk in the elderly, or about exactly how exposure to UOGD-related activities may be contributing to such risk.

To learn more, the researchers studied a cohort of more than 15 million Medicare beneficiaries—people ages 65 and older—living in all major U.S. UOGD exploration regions from 2001 to 2015. They also gathered data from the records of more than 2.5 million oil and gas wells. For each Medicare beneficiary’s ZIP code and year in the cohort, the researchers used two different statistical approaches to calculate what the exposure to pollutants would be from living either close to UOGD operations, downwind of them, or both, while adjusting for socioeconomic, environmental, and demographic factors.

The closer to UOGD wells people lived, the greater their risk of premature mortality, the study found. Those who lived closest to wells had a statistically significant elevated mortality risk (2.5% higher) compared with those who didn’t live close to wells. The study also found that people who lived near UOGD wells as well as downwind of them were at higher risk of premature death than those living upwind when both groups were compared with people who were unexposed.

“Our findings suggest the importance of considering the potential health dangers of situating UOGD near or upwind of people’s homes,” said Longxiang Li, a postdoctoral fellow in the Department of Environmental Health and lead author of the study.

Unmaking a mess

Solving Freetown’s garbage crisis is key to managing disasters and disease

By Adebayo Lawrence Thomas and Suphian Bangura

At 6am on a Thursday, Sallieu Bangura, dressed in bright orange regulation clothing, clocked in at the premises of a private waste management company contracted by the Sierra Leone government to collect solid and liquid refuse in Freetown. Bangura and four colleagues work one designated location a day over the course of an eight-hour shift, collecting garbage from some 150 households. Like they do most mornings, they loaded a truck with bins, shovels, and rakes, equipped themselves with protective gear, and drove out of the premises. Today, they are headed to Regent Village, some 10 kilometres away. Bangura earns Le 800,000 (approximately $78) a month. He took up the job some six years for the steady income it offered, because he “didn’t want to sit idle or become a criminal” .

FCC mayor Yvonne Aki-Sawyerr

“People look down on us as if we are not human beings,” says Bangura a little later, pulling two garbage bins behind him down Dadley Street in Regent. “They treat us like we are filthy and stinking.”

But Bangura believes in the value of his work. “There used to be piles of waste in some areas around the city, but now we are trying to control it,” he says. “We are helping people practice proper waste management and it has made a huge difference in our city.”

Though critical, the efforts of people such as Bangura are just not enough to overcome the waste disposal problem that is troubling parts of Freetown and contributing to its disaster vulnerability. A report published by Concern Worldwide, an Ireland-based charity that also operates in Freetown, says only 21 per cent of the waste in Freetown is appropriately disposed of, with the remainder, amounting to about 550 tonnes a day, either burned or discarded on the roads, gutters, and waterways. The problem is not just one of hygiene and aesthetics. The garbage choking the already inadequate drainage system is a key ingredient of the rainy season disasters that Freetown has seen in recent years. The combination of trash-clogged drains, intense rainfall, overburdened urban infrastructure, and the proliferation of slums and informal communities — many of which are built with flimsy materials and located in vulnerable areas — has resulted in floods and mudslides displacing and killing thousands of Sierra Leoneans in recent years.

Mustapha Kemokai, Environment and Sanitation Officer at the Freetown City Council (FCC), which oversees waste management in the city, acknowledges that the garbage situation is “extremely tough”, particularly in the wet season. According to him, “a lot of money” is being spent on waste collection, but “people dump their trash in the drains, creating flooding”.

While this may be true, it presents an incomplete picture of Freetown’s garbage challenge. Many people cannot afford to make use of a private waste disposal service, which requires registering for a fee of Le 125,000 ($12), and then paying the same amount each month for the weekly garbage pick-up. In a country where the monthly minimum wage is only Le 600,000 ($48), these costs can be prohibitive for many. In addition, the coverage of the service is limited and does not extend to some of the informal settlements that need it most.

While more affordable alternatives for garbage collection do exist, these too have their limitations. One such initiative is Klin (Clean) Sierra Leone, which is overseen by the FCC. This programme aims to “empower” unemployed youths by recruiting them to collect garbage door to door, using pushcarts rather than trucks, and offering a more flexible pay-as-you-go arrangement.

Abdullai Kamara, who has registered his cart with the FCC, works according to this model. “I push my cart from one community to another, shouting ‘Klin Salone’, and those who want a pick-up call for me. The money depends on the amount of garbage,” he says. Like Bangura, he believes he is helping keep his country clean and “with cleanliness comes development”. Kamara says he wouldn’t mind carrying on in this line of work for the rest of his life. However, even though he handles potentially hazardous waste, he does not have any protective gear to wear during his 7am — 7pm shifts, six days a week. When garbage tumbles free from his unsteady, overburdened cart, he pushes it back with his bare hands.

While the employees of a private company and independent sanitation workers like Kamara may work under radically different conditions, it is worth noting that in a country where there are barely any organised provisions for recycling or composting, most of the garbage they collect ends up at the same location: Kingtom landfill, a vast (and growing) expanse of festering garbage. It is still a better destination than another sprawling site nearby that serves as an informal landfill, and which also happens to be one of the largest and most impoverished shanty settlements in the city.

A few decades ago, Kroo Bay was a fishing village with a relatively clean beach. Today, according to a report by the development organisation Volunteer Services Overseas, it houses around 10,000 people, some of whom live in rickety huts built “upon a layer of garbage… around three to five feet deep, beneath which lies sand”. These congested structures — assembled haphazardly from discarded metal, sticks, rubbish, and mud — lie near an estuary, making them extremely vulnerable to flooding, a problem that is exacerbated by the trash and sewage that is indiscriminately consigned to the river. Every year, for more than a decade, the settlement has faced floods in the rainy season as well as a host of incumbent health risks, such as malaria and cholera, fostered by reeking pools of stagnating water. Sierra Leone’s average life expectancy is just 54 years, and Kroo Bay’s is believed to fall well below that average.

“When it floods here during the rainy season, it’s not just water but trash and all kinds of filth,” says John Bangura, a Kroo Bay resident. This problem extends to many other neighbourhoods in Freetown, which is one of the wettest cities on the West African coast (receiving average annual rainfall of more than 3,500mm) and where a majority of the population resides in slums or unplanned settlements.

Currently, Freetown’s ability to deal with the garbage it generates falls gravely short of the requirements of the people living in slums and in difficult-to-reach parts of the city — as is clearly evidenced in the overflowing garbage cans, mounds of exposed trash on virtually every street block, and makeshift landfill sites on the outskirts of the city. This unregulated trash disposal has ecological, human health, and economic repercussions in most communities.

“Solid waste management in Freetown poses vexing problems such as low service coverage, insufficient budgets, highly inadequate equipment, substantial inefficiencies such as high costs, low quality service, low labour productivity, poor public attitudes, and widespread illegal dumping,” Breda Gahan, a Senior Health and HIV/AIDS Advisor for Concern Worldwide, says. According to her, the waste management system in Freetown has suffered due to changing hands between multiple public and private organisations. “The shifting authorities — the political football — have made handling municipal solid waste in Sierra Leone one of the most expensive urban services, accounting for up to 3 per cent of the country’s GDP and 45 per cent of municipal income,” Gahan says.

Melissa Medegbe, an Environment Officer with the Environmental Protection Agency (EPA) believes that the burgeoning garbage problem is rooted in the lengthy civil conflict that wracked Sierra Leone from 1991 to 2002. The existing infrastructure was severely damaged during this period, and was later unable to cope with the growth in the city’s population to more than a million currently — a number that is expected to double by 2028.

Given how congested and prone to disaster Freetown already is, the crisis could get a lot worse unless immediate steps are taken to fund and execute waste management initiatives. According to Medegbe, the most important step for now is to bring more regularity in waste management, which in turn will help attract more funding.

“We require more funding and vehicles to manage waste in Freetown. We have a lot of trash, but not enough vehicles to transport it to the landfill… people often just throw their trash into the drains, causing it to flow on to the roadways and creating blockages,” Medegbe says, adding that the road network also needs to be repaired in order to allow free flow of traffic and lessen congestion. “There is a need for additional designated waste transition sites. We have very few now, just about two — and this creates opportunities for illegal dumpsites.”

Cover illustration: Felix Rhodes. Additional reportage: Abdulrahman Koroma

A significant issue in Freetown’s waste management is a lack of awareness among the public, which compounds the problem of inefficient infrastructure. Recognising this, the EPA and FCC have intensified their mass sensitisation efforts, especially in the ongoing rainy season, in the hope that it will create an attitudinal shift in the people and motivate them to dispose of waste properly.

Medegbe believes that Sierra Leone should work with international organisations to holistically address the issue of waste management. Some advances have already been made in this direction. For instance, in 2019, the International Organization for Migration (IOM) gave trash collection equipment — including bikes, shovels, and safety gear — to the FCC for the setting up of 20 sustainable micro-enterprises that would conduct door-to-door rubbish collection in Freetown. Additional initiatives of this nature could help promote better outcomes for waste management.

Re-evaluating waste as a resource could also lead to several gains. According to a UN assessment, 80 per cent of Freetown’s trash could be recycled or composted, but this potential is still untapped. “Currently, there are few organisations into this venture, like Shae recycling, the first indigenous waste recycle company. The advantages of recycling will compel individuals to consider it,” Medegbe says. The energy-generation uses of waste should also be explored, adds Gahan, pointing to a 2014 study that estimated the city’s energy potential at 398.2kWh per tonne of waste — enough to meet the electricity needs of 50 households in one day.

According to Medegbe, the Sierra Leone government should create a supportive framework to encourage public-private partnerships (PPP) geared towards transforming waste into wealth via recycling, electricity- and gas-generation, and creating employment opportunities. “The international community could also ameliorate the situation by collaborating with Sierra Leone,” Medegbe says. Until then, however, the rainy season will continue to be a harbinger of dread in Freetown.

NOTE: This article was first published on 23 July 2021 on, which works to strengthen disaster communication in Sierra Leone.

Graphene shield shows promise in blocking mosquito bites

NIH-funded project shows graphene could provide alternative to chemicals in insect repellant and protective clothing.

An innovative graphene-based film helps shield people from disease-carrying mosquitos, according to a new study funded by the National Institute of Environmental Health Sciences (NIEHS), part of the National Institutes of Health. The research, conducted by the Brown University Superfund Research Center, Providence, Rhode Island, is published in the Proceedings of the National Academy of Sciences.

Bite by an Aedes mosquito. This species can transmit diseases such as chikungunya, dengue, and Zika. NIAID

“These findings could lead to new protective methods against mosquitos, without the environmental or human health effects of other chemical-based repellants,” said Heather Henry, Ph.D., a health scientist administrator with the NIEHS Superfund Research Program.

Researchers found dry graphene film seemed to interfere with mosquitos’ ability to sense skin and sweat because they did not land and try to bite. When they looked closely at videos taken of the mosquitos in action, they noticed the insects landed much less frequently on graphene than on bare skin. The graphene film also provided a strong barrier that mosquitos could not bite through, although when wet it did not stop mosquitos from landing on skin.

“We set out imagining that graphene film would act as a mechanical barrier but after observing the mosquitos’ behavior, we began to suspect they were not interested in biting,” said Robert Hurt, Ph.D., director of the Superfund Research Program at Brown University. 

Mosquitos threaten public health by carrying infectious viruses such as Yellow Fever, West Nile, and Zika, leading to disability and death for millions of people every year.

Results show that graphene, a tight, honeycomb lattice of carbon, could be an alternative to chemicals now used in mosquito repellants and protective clothing. Until this study, insect-bite protection was an unexplored function of graphene-based materials.

Several years ago, Hurt began devising suits with graphene to protect workers against hazardous chemicals at environmental clean-up sites. He pointed out a wealth of literature demonstrates graphene’s impermeable qualities. Graphene is invisible to the unaided eye, yet harder than diamonds, stronger than steel, and more conductive than copper. Since its discovery in 2004, graphene has been used for a variety of barrier and filtration purposes.

“This innovation using graphene to repel mosquitos could help reduce the burden of ill health associated with a number of infectious diseases and might reduce the need for pesticides to eradicate the mosquitos that carry them,” said William Suk, Ph.D., director of the NIEHS Superfund Research Program. “New material such as this one should be assessed in the field to determine full public health implications.”

More crackdown on plastic pollution urgently needed – WHO

Reduction in plastic pollution benefits the environment

The World Health Organization (WHO) has called for a reduction in plastic pollution to benefit the environment and reduce human exposure.

WHO launched its first report today on microplastics in drinking-water, cautioning the that while findings show a low risk to human health, more research is needed.

treated tap and bottled water have raised questions and concerns about the impact that microplastics in drinking-water might have on human health.

WHO notes that the report critically examines the evidence related to the occurrence of microplastics in the water cycle (including both tap and bottled drinking-water and its sources), the potential health impacts from microplastic exposure and the removal of microplastics during wastewater and drinking-water treatment.

“Recommendations are made with respect to monitoring and management of microplastics and plastics in the environment, and to better assess human health risks and inform appropriate management actions, a number of key knowledge gaps are identified.”

“We urgently need to know more about the health impact of microplastics because they are everywhere –  including in our drinking-water,” says Dr Maria Neira, Director, Department of Public Health, Environment and Social Determinants of Health, at WHO. “Based on the limited information we have, microplastics in drinking water don’t appear to pose a health risk at current levels. But we need to find out more. We also need to stop the rise in plastic pollution worldwide.”

According to the analysis, which summarizes the latest knowledge on microplastics in drinking-water, microplastics larger than 150 micrometres are not likely to be absorbed in the human body and uptake of smaller particles is expected to be limited.  Absorption and distribution of very small microplastic particles including in the nano size range may, however, be higher, although the data is extremely limited.

Of all human diseases, 60% originate in animals – “One Health” is the only way to keep antibiotics working

Antibiotic resistance is a growing threat to global health. As a result of infection with drug-resistant bacteria an estimated 700 000 people die each year worldwide. A total of around 33 000 die annually in the European Union and European Economic Area, and this number is increasing all the time.

Many of the same microbes (e.g. bacteria, viruses, fungi, parasites) affect both animals and humans via the environment they share and 60% of all human diseases originate in animals. This means that when microbes develop drug resistance in animals, they can easily go on to affect humans, making it difficult to treat diseases and infections.

“Human, animal and environment health are all equally responsible for the correct use of antimicrobials and to avert the threat of antimicrobial resistance,” said Dr Zsuzsanna Jakab, WHO Regional Director for Europe. “As we strive to ensure that antibiotics are rightly used in the community and in health-care settings, one sector alone will not solve the problem. A ‘One Health’ approach brings together professionals in human, animal, food and environment health as one force, and as such is the only way to keep antibiotics working. I call on all European countries to secure the highest commitment to this approach from the whole of society and the whole of government.”

“With 33 000 deaths each year as a consequence of an infection due to bacteria resistant to antibiotics and €1 billion in annual health-care expenditure, we need to ensure that antibiotics are used prudently and that infection prevention measures are in place in all settings across Europe,” stated Andrea Ammon, Director of the European Centre for Disease Prevention and Control (ECDC). She added, “Since the rates of antibiotic resistance and the rates of antibiotic consumption as well as infection prevention practices vary from country to country, it is essential to tailor strategies to address specific needs. ECDC calls for continued action at all levels”.

This year, the WHO European Region will mark the 4th annual World Antibiotic Awareness Week on 12–18 November, by committing to closer collaboration across sectors to protect human, animal and environment health, in the spirit of One Health.

Personal care product chemicals found in men’s urine samples

Chemicals known as phthalates and parabens are widely used in personal care products, however, it is unknown if this is an important exposure source for men. A new study by Harvard T.H. Chan School of Public Health researchers found these chemicals present in urine samples taken several hours after men in the study used the products.

The study was published online August 24, 2017 in Environmental Health Perspectives.

Capture-d_écran-2012-04-10-à-14.44.24Phthalates are used as plasticizers in scores of products ranging from vinyl flooring to food packaging and parabens are widely used in personal care products, such as cologne, sunscreen, and deodorants, to extend shelf life. Some of these chemicals are endocrine disruptors and have been linked with adverse health outcomes.

Lead author Feiby Nassan, postdoctoral fellow in the departments of Environmental Health and Nutrition, and colleagues tested 1,037 urine samples from 400 men in the Environment and Reproductive Health (EARTH) Study. The men reported their use of 14 personal care products and provided urine samples between 2004–2015.

The largest amount of one phthalate was associated with use of cologne/perfumes as well as deodorants. The largest percent increase for parabens was associated with the use of sunblock lotion and hand/body lotion. The presence of the chemicals was generally higher within six hours of product use.

Other Harvard Chan authors included Russ Hauser, Frederick Lee Hisaw professor of reproductive physiology and acting chair, Department of Environmental Health, senior author; Dean Michelle A. WilliamsBrent Coull, professor of biostatistics; Joseph Braun, visiting scientist in environmental health; Audrey Gaskins, research associate in nutrition; and Jennifer Ford, research nurse manager for the EARTH study.