Tiny fragments of plastic known as nanoplastics interact with a particular protein that is naturally found in the brain, creating changes linked to Parkinson’s disease and some types of dementia, according to a Duke University-led study.
In Science Advances, the researchers report that the findings create a foundation for a new area of investigation, fuelled by the timely impact of environmental factors on human biology.
“Parkinson’s disease has been called the fastest growing neurological disorder in the world,” said principal investigator, Andrew West, PhD, professor at Duke University School of Medicine.
“Numerous lines of data suggest environmental factors might play a prominent role in Parkinson’s disease, but such factors have for the most part not been identified.”
Improperly disposed plastics have been shown to break into very small pieces and accumulate in water and food supplies, and were found in the blood of most adults in a recent study.
“Our study suggests that the emergence of micro and nanoplastics in the environment might represent a new toxin challenge with respect to Parkinson’s disease risk and progression,” West said.
“This is especially concerning given the predicted increase in concentrations of these contaminants in our water and food supplies.”
West and colleagues in Duke’s Nicholas School of the Environment and the Department of Chemistry at Trinity College of Arts and Sciences found that nanoparticles of the plastic polystyrene — typically found in single use items such as disposable drinking cups and cutlery — attract the accumulation of the protein known as alpha-synuclein.
West said the study’s most surprising findings are the tight bonds formed between the plastic and the protein within the area of the neuron where these accumulations are congregating, the lysosome.
Researchers said the plastic-protein accumulations happened across three different models performed in the study – in test tubes, cultured neurons, and mouse models of Parkinson’s disease.
West said that questions remain about how such interactions might be happening within humans and whether the type of plastic might play a role.
“While microplastic and nanoplastic contaminants are being closely evaluated for their potential impact in cancer and autoimmune diseases, the striking nature of the interactions we could observe in our models suggest a need for evaluating increasing nanoplastic contaminants on Parkinson’s disease and dementia risk and progression,” West said.
“The technology needed to monitor nanoplastics is still at the earliest possible stages and not ready yet to answer all the questions we have,” he said.
An estimated 5.5 million people died of heart conditions linked to lead poisoning in 2019 – more than the number killed by outdoor air pollution over the same period. That’s according to a recent study in the journal Lancet Planetary Health. The number is substantially higher than previous estimates. According to a 2021 World Health Organization (WHO) report there were roughly 900 000 deaths linked to lead exposure in 2019.
The researchers also found that exposure to lead (a powerful neurotoxin) causes more harm to children’s intellectual development than previously thought. The paper estimates that in developing countries, where the condition is most prevalent, a child with average levels of lead exposure loses nearly six IQ points from the metal in their first five years of life (average IQ is 100).
While only about 2% of those living in wealthy countries have lead poisoning, the situation is very different for those in poorer parts of the world. A 2021 study found that nearly half of all children living across 34 low-and-middle income countries have lead poisoning – which is typically defined as a person having at least five micrograms of lead per 100mL of blood.
It’s estimated that the average child in South Africa is well above this threshold – at about 5.59 micrograms. And worryingly, the metal can still cause harm below the clinical threshold. Indeed, any increase in a person’s blood-lead levels is associated with greater health risks, even at the lowest detectable levels.
The metal can make its way from these products into people’s bodies through a number of routes. In some cases – like with alternative medicines or spices – people directly ingest contaminated goods. In others, people breathe in lead dust, which can be generated by unregulated industrial practices. For instance if lead-acid battery recyclers lack proper safety and environmental standards – as is often the case in developing countries – recyclers may simply pour lead-based battery solution onto the ground, contaminating the soil.
Children are most at risk. For one, they’re more likely to put items that contain lead in their mouths, like toys covered in lead paint, or even a thumb coated in lead dust. Secondly, they’re closer to the ground and therefore breathe in more lead-contaminated dust. The theme of this year’s WHO-backed International Lead Poisoning Prevention Week was “End childhood lead poisoning”.
After it’s ingested or inhaled, some lead is excreted, while the rest is absorbed into the bones, teeth and blood. Children absorb more of the metal than adults and once it’s in the blood, lead can be distributed to various organs in the body. This includes the heart as well as the brain, where it can interfere with neurotransmitter systems involved in learning and memory.
No threshold
The new study in Lancet Planetary Health adds to a growing body of evidence that global lead exposure is far more detrimental to human health than previously thought. While people began understanding that lead was poisonous several thousand years ago, it was only recently that evidence accumulated showing that even tiny amounts of lead can cause damage.
Part of the reason is simply because we didn’t have data on low-level exposure until recently, explains Bjorn Larsen, the study’s lead author. Most people in industrialised countries had very high blood-lead levels during most of the 20th century. For instance, in the late 1970s the average American child had about 15 micrograms of lead per 100mL of blood, which is about 25 times the average today, and three times the present-day threshold for lead poisoning. A major reason was leaded gasoline, which was introduced in the 1920s and phased out from the 1970s onward.
Thus, says Larsen, testing the effects of blood-lead levels that we would now perceive as low wasn’t always possible. For instance, to show that even one or two micrograms of lead per 100ml of blood is harmful, researchers would need to compare people at this (very low) level to those with no lead to observe if they come off worse. But if almost everyone is above two micrograms, this becomes close to impossible as there isn’t anyone to test. And in the absence of data, some simply assumed that the metal was only problematic above a particular threshold.
Bruce Lanphear, a professor of public health at Simon Fraser University, was the lead author of a seminal 2005 paper that showed that lead was associated with declines in IQ even below the clinical threshold set at the time (10 micrograms of lead per 100mL of blood). He explains that by the mid-1990s, when 95% of people were below that threshold, many felt that lead was no longer much of an issue: “my advisors at that point said get out of this line of research, the problem seems to be going away and there won’t be any funding for it. And they were right about one of those two things – I haven’t gotten much funding,” Lanphear says.
As blood-lead levels continued to drop and scientists like Lanphear could study the effects of lead on children’s intellectual development at lower levels, a new consensus emerged. Larsen explains: “Now people are willing to say that in all likelihood the correct way to estimate things is that there is some effect on IQ as soon as we can detect lead in the blood – even at the lowest level these effects start”. Indeed, according to a WHO factsheet, “there is no known safe blood-lead concentration”.
Not only that, adds Lanphear, but research shows that “proportionately, we see greater harms – greater reductions in IQ – at the lowest measurable lead levels”. In other words, the more lead you have in your body, the worse it is, but going from one microgram of lead per 100ml of blood to two micrograms causes more additional harm than going from 15 micrograms to 16. Thus, it’s strangely only through the decline in lead poisoning that its most pernicious effects have been revealed.
Lead ‘poisons’ our cells
As more data is gathered, estimates of the harm caused by lead are constantly being revised upward. The finding that lead is linked to 5.5 million cardiovascular deaths a year is over six times the number previously determined by a 2019 study. It should be noted however that the new estimate is relatively uncertain – the researchers estimate the real value is most likely in the range 2.3 to 8.3 million.
Part of the reason for the updated estimates is that the 2019 research had only looked at the effects of lead on blood pressure, while the new paper considers a wide variety of cardiovascular problems associated with lead.
According to a statement by the American Heart Association from earlier this year these effects include injury to the cells that line the blood vessels, oxidative stress (which can result in cell and tissue damage) and coronary heart disease, which is when the blood flow is restricted, increasing the risk of a stroke or heart attack.
Gervasio Lamas, Chief of cardiology at Mount Sinai Medical Centre and the lead author of the statement, explains that heavy metals like lead can erode cardiovascular health through two broad channels: “one is that toxic metals typically will end up replacing essential metals or ions in vital cellular reactions,” he says.
For instance, lead replaces the calcium in our cells, a mineral which is involved in keeping our hearts pumping, our blood clotting and our heart muscles properly functioning. By removing calcium, lead “poisons these cells,” says Lamas.
He tells Spotlight that the other main route is that toxic metals often interfere with our antioxidant mechanisms. Antioxidants are molecules which deactivate harmful free radicals (chemicals that can attack our cells and DNA). Lead disrupts these antioxidant defences, he says. As a result, free radicals build up, which may cause the blood vessels to harden (called atherosclerosis), blocking blood flow.
Different strands of evidence point in the same direction
To arrive at the conclusion that 5.5 million people died from lead-induced heart conditions, Larsen and his colleague relied on two large observational studies from the United States (where there is lots of data). These studies measured the blood-lead levels of thousands of people and looked at what happened to them over time. They showed that those who had more lead in their blood were more likely to die of heart complications at a younger age, even when controlling for lots of other factors.
Larsen and his colleagues used estimates from these studies to develop a model which calculates the increase in a person’s risk of dying of heart disease at different levels of lead exposure. They then plugged in the blood-lead levels that we observe among people around the world to estimate how much cardiovascular death the metal is linked to.
One contention that emerges from research like this is whether it really shows cause and effect. As Lamas notes, “the populations that are most affected by high lead levels are [more likely] to be underprivileged in some way. They are often either poor or have access to less healthcare or live in areas that are more generally contaminated – things that you would expect would in any case cause [health] problems for them”.
When we find that people who have more lead in their blood die of heart disease more often, this may be due to one of these other factors.
But according to Lamas, there are a number of reasons to be confident that lead is actually the driver of heart disease. The first is that when observational studies (like the ones discussed above) measure the relationship between people’s lead levels and cardiovascular disease, they control for a range of other risk factors, including their socioeconomic status. “Even when you do that, lead still sticks out like a big sore thumb,” Lamas notes.
The other reason is that there are lots of different sources of evidence that all find lead damages cardiovascular health: “there are direct experiments where patients or animals are infused with lead and those show that arterial function [i.e. the ability of our arteries to transport blood] is diminished,” Lamas explains.
Finally, Lamas points to the results of a randomised clinical trial which he and his colleagues published in 2013. In it, they took over 1700 patients who had recently suffered from a heart attack and randomly split them into different groups. One group received a treatment for lead poisoning called EDTA chelation. This is an intravenous medicine that binds with toxic metals in the body before being urinated out. Those who didn’t receive the chelation therapy got a placebo drug.
Five years later, those who got chelation therapy appeared to be better off. They performed better than the placebo group when measured by a composite index that combines factors like patients’ risk of dying and their need to return to hospital for further procedures.
With so many different kinds of research pointing in the same direction, Lamas believes the evidence that lead plays a causal role in heart disease is about as conclusive as in the case of high cholesterol.
And if lead truly is killing 5.5 million people through heart conditions each year, this places it among the top risk factors for cardiovascular disease globally. Despite this, lead poisoning along with exposure to other toxic metals, remains a remarkably overlooked issue. Lamas explains, “at the individual physician level – sitting across from a patient – I’m the only cardiologist I know who routinely checks lead, mercury, arsenic and cadmium”.
Note: This is part one of a two-part Spotlight special series on lead poisoning.
Netcare Christiaan Barnard Memorial Hospital has earned a prestigious five-star rating from the City of Cape Town’s Water and Sanitation Directorate, joining the esteemed ranks of organisations dedicated to water sustainability. The accolade underscores NCBMH’s commitment to responsible water management and aligns with the hospital’s ongoing efforts to champion prudent and sustainable management of natural resources, supporting water-sensitive urban living.
Netcare Christiaan Barnard Memorial Hospital (NCBMH) has earned a prestigious five-star rating from the City of Cape Town’s Water and Sanitation Directorate, joining the esteemed ranks of organisations dedicated to water sustainability. The accolade underscores NCBMH’s commitment to responsible water management.
The City of Cape Town’s Water Star Rating Certification Awards acknowledged NCBMH’s dedication to best water use, supply, conservation and discharge practices. This recognition aligns with the hospital’s ongoing efforts to champion prudent and sustainable management of natural resources, supporting water-sensitive urban living.
“We are proud to be part of a community leading the charge in climate-smart healthcare transformation and are committed to playing a proactive role in averting a potential water crisis in Cape Town and across South Africa,” said André Nortje, Netcare’s environmental sustainability manager.
Nortje emphasised Netcare’s dedication to minimising environmental impact: “Our commitment extends beyond accolades. Efforts to conserve water, reduce waste and save electricity should be high on every South African’s agenda, and we are committed to doing our part to drive sustainability.”
NCBMH’s water conservation initiatives include a sophisticated greywater harvesting system, as well as a desalination plant capable of providing the entire facility’s water needs. These initiatives, as well as the installation of low-flow showerheads and aerator-equipped taps throughout the hospital, can achieve water savings of approximately 60 000 kilolitres for the facility per annum. The hospital’s desalination plant, installed in 2019, also has the filtration capacity to support all Netcare facilities in the City of Cape Town in a disaster situation.
Netcare achieved a 23% reduction in water consumption at Group level between 2014 and 2020. Nortje outlined the 2030 aim to further reduce the company’s impact on the natural potable water sources by implementing grey- and black-water recycling projects within selected facilities.
The company’s sustainability strategy, initiated in 2013, addresses electricity use, waste reduction, and water management. The Group aims to further reduce its impact on water sources by an additional 20% from the 2020 baseline. The strategy includes efficient equipment deployment, the evaluation of greywater and blackwater treatment for potable water and an operational efficiency drive.
“We believe every business should be a good corporate citizen contributing to our country’s future. At Netcare, we want to show South Africa and the world that sustainability is possible and that YOU can make a difference. The certification allows us to showcase our efforts to inspire businesses around us to join in the fight against wastage,” concluded Nortje.
A study in mice conducted by the University of Cordoba proves that exposure to mixtures of metals and drug residue exacerbates health impacts, and evaluates the positive effects of a diet enriched in selenium to reduce this harm.
People are exposed daily, through the environment and their diets, to external substances that can be harmful to their health. Metals and the residue of pharmaceuticals, for example, in high doses, contaminate water and food, creating mixtures where they can interact, with this increasing their individual toxicity.
Analysing the effects of environmental pollution on organisms is essential to develop regulations establishing maximum doses of these pollutants for people. But mixtures of pollutants pose unknown challenges as they may interact with each other.
To understand the health effects of exposure to these ‘cocktails of contaminants’, a team at the University of Cordoba, evaluated, in mice, the toxicity of a mixture of contaminants that is very common in the environment and that accumulates along the food chain: a combination of metals (arsenic, cadmium, mercury) and drugs (diclofenac, flumequine).
In order to determine how these compounds interacted with each other, “we studied the controlled exposure of mice to this mixture and analysed how it affects the proteins in the liver; that is, how their liver proteostasis changes when ingesting these mixtures of contaminants for two weeks,” explained Professor Nieves Abril, senior author of the paper published in Science of the Total Environment.
Their conclusion is negative: the cocktail effect synergises these compounds, doing increased damage to health when the compounds act together.
“We used a massive protein detection technique (shotgun proteomic), which allowed us to compare how the proteins of the group exposed to the mixture of contaminants were altered compared to the control group,” April explained.
Of the proteins affected, they selected 275 as sentinels to verify what was changing and, after computer analysis, they were able to determine the metabolic pathways that were altered and their consequences for health. These analyses revealed a disproportionate defence response having a contrary and harmful effect on the system.
The researcher stressed that “although these pollutants generated oxidation in the cells separately too, when they acted together we found that the oxidation was so intense that all the antioxidant defence responses were activated continuously, without deactivating them, which ends up doing damage and causing many proteins to stop working.” The analyses showed a sustained expression of the response mediated by NRF2, which is the regulator that sets in motion a good part of the antioxidant defences, which caused a reducing stress.
Selenium as hope
It’s not all bad news in the study, as selenium could be a way to reduce the damage caused by exposure to these pollutants. A third group of mice were given doses of selenium, a mineral often found in vitamin supplements found in pharmacies, and proteomic analyses showed relief from the molecular damage done by the pollutants.
Selenium itself is an oxidant, but in low doses it activates responses in a controlled manner, predisposing the body to better defence.
About ten billion tonnes of plastic have been produced to date, of which around six billion tonnes have been discarded as waste. This is a severe threat to the environment, particularly oceans and lakes.
When plastics break down into particles smaller than five millimetres we call them microplastics. They are especially worrying.
A study on mice exposed to microplastics found them in every tissue examined, and showed behavioural changes and heightened inflammation. While the exact effects on human health are not yet known, the risk is high enough that we should be very cautious about allowing them to pervade our atmosphere and food supply.
Microplastics have even been detected in high amounts in clouds, where they may affect rainfall patterns. They can also enter our food supply through rainfall.
A recent study of sediments in the Vaal river found an alarmingly high abundance of microplastics, which may enter the local food supply through crop irrigation. The sampling in this study was done in the region of the Vaal River Barrage, which is downstream of the Vaal Dam and fed by rivers that pass through heavily populated areas including Johannesburg.
Sampling at the Barrage gives direct insight into the rates at which we are producing microplastics in major population centres. And sampling at the Vaal Dam, which is the major drinking water supply for Gauteng, provides insight into the extent to which our drinking water is affected. Both these sampling points are needed as we track the levels of microplastics. Those levels are likely to rise dramatically; the microplastics we are seeing currently are only the tip of the iceberg, as there is a lag between the production of plastic, and it breaking down into microplastics.
Microplastic proliferation is not tied directly to accumulation of waste plastic. Examination of microplastics to ascertain their source is not an exact science, but it is reported that the main sources of microplastic pollution, at least for now, are car tyres and textiles and the pollution arises, not at the end-of-life when these are discarded as waste, but during their day-to-day use.
In other words, even if we solve the problem of waste plastic, we would still face the problem of microplastics that are emitted during the normal lifespan of products made of plastic.
There are, fortunately, some concrete steps that people can take to reduce personal exposure to microplastics. While microplastics are clearly able to travel throughout the atmosphere, their levels are concentrated around the sources releasing them. Microplastic concentrations are higher in indoor than outdoor air; old-fashioned fresh air and good ventilation are beneficial. So too is regularly wiping down surfaces, as they accumulate microplastic dust. Household air filters may also reduce microplastic concentrations.
Perhaps the most useful thing we as individuals can do is to have a different relationship with clothing. Synthetic fabrics are a prolific source of microplastics. These are released in our immediate surroundings, making our exposure to them disproportionately high.
Most microplastic release from textiles occurs within the first few washes after purchase, so purchasing long-lasting clothing rather than frequently replacing items of clothing can reduce your exposure, as can choosing natural fabrics such as cotton, where possible.
The other major source of microplastics is car tyres, which shed microplastics constantly as they wear down.
There are also activities which may seem environmentally-friendly but probably exacerbate microplastics pollution.
At first glance, this appears to be an environmental win-win. But recycled products tend to be more susceptible to the abrasion that causes microplastic release. Moreover, waste and recycled plastics tend to wear out more quickly and require replacement more frequently.
This is perhaps most harmful in the case of clothing made of waste or recycled plastic; the release of microplastics in early washes will be more severe because of the weaker polymer. This is particularly worth highlighting because recent research has shown that tumble-drying of synthetic textiles results in prolific microplastic release, much of which may be discharged into the indoor environment and breathed in or otherwise consumed.
Currently we have no practical way to remove microplastics from the environment; the particles are simply too small and widely dispersed. This means that we must exercise extreme caution to minimise emissions and our personal exposure to them.
South Africa’s sewage crisis has dire consequences for public health, waterways, and ecosystems. Outdated and poorly maintained wastewater infrastructure due to insufficient investment is one factor that results in poor waste management. The strain of rapid urbanisation with inadequate sanitation facilities in informal settlements and the exacerbating impact of climate change through increased rainfall events are also factors that contribute to poor waste management. Despite these challenges, there is room for optimism. Collaborative efforts between government and the private sector have the potential to address this dire situation, bringing forward practical, affordable solutions that hold the promise of a cleaner, healthier future for all communities.
A public health crisis: deadly waterborne diseases
South Africa’s persistent sewage crisis recently sparked a new cholera outbreak, primarily stemming from dysfunctional municipal sewage systems. Over 90% of the nation’s 824 treatment plants discharge untreated or partially treated sewage into our limited water resources. As of June 2023, the Department of Health had documented 1,045 suspected cholera cases across five provinces, with 197 cases confirmed by laboratory testing, directly linked to compromised water supply.
This crisis disproportionately impacts both urban and rural regions, where access to clean water and sanitation remains a pressing concern. Impoverished communities often rely on highly polluted water sources contaminated by sewage from overwhelmed treatment plants, further straining water purification efforts to meet safety standards. Recognising the intrinsic connection between drinking water quality and wastewater treatment is crucial, necessitating immediate attention and resolution.
However, a significant challenge faced by South African communities is the prohibitive cost of implementing waterborne sanitation solutions everywhere. With over four million latrines and roughly 50 million people lacking adequate sanitation, conventional waterborne systems are neither viable nor cost-effective comprehensive solutions.
South Africa’s water quality reports: red flags aplenty
The Blue Drop Report 2023, released in June 2023, paints a concerning picture of South Africa’s drinking water quality. While major cities maintain safe water, outlying areas face contamination and infrastructure challenges. Key statistics from the report reveal that the average Technical Site Assessment (TSA) score for water treatment systems is 69%, indicating partial functionality. About 15% of water supply systems are in poor or critical condition, with only 33% having Water Safety Plans, posing significant risks to water quality. Additionally, 50% of municipalities struggle with bad or poor microbiological water quality.
Wastewater and water wasting: two major risks
The 2023 Green Drop Report assesses wastewater treatment systems, showing a decline with an average score of 50%. Regional disparities persist, with Eastern Cape and Limpopo scoring lowest, while the Western Cape and Gauteng lead. The No Drop Report examines water losses, revealing a decline in overall performance in 2023, with an average score of 65%, which means that one-third of supplied water is wasted before it reaches consumers.
These reports collectively underline the urgent need to enhance drinking water quality in South Africa. Municipalities must focus on prioritising infrastructure maintenance and upgrades, implement risk-based water quality management, and strengthen compliance with standards. The Department of Water and Sanitation must offer more support to municipalities. Failing wastewater treatment facilities exacerbate drinking water purification, risking tap water safety and triggering further potential health and environmental crises. Therefore, they must take steps to safeguard water quality and address sewage infrastructure issues.
Rapid crisis intervention required
South Africa’s sewage crisis is a dire challenge that requires immediate action and innovative solutions. In recognising the inextricable link between sewage waste management and water quality, we must also acknowledge that this crisis cannot only be addressed by government without support from private sector industry leaders and experts. Portable water treatment package plants are available, along with small filtration and sterilisation systems for communities. Wastewater packaged treatment plants and solutions can help both alleviate immediate concerns and contribute to long-term sewage management strategies. Further neglecting the sewage problem and the critical maintenance of existing infrastructure will only deepen our water crisis. For this reason, the government needs to prioritise investment in sewage treatment infrastructure and implement practical, affordable solutions across all communities.
Mitigating South Africa’s sewage crisis
If municipal water supplies deteriorate further, sanitation specialists will be required to step in with a range of interventions. These extend from portable water treatment packaged plants to improve water quality at its source, to small-scale filtration and sterilisation systems designed for household use to ensure safe drinking water directly from the tap. From a contamination perspective, it is critical to reduce sewage entry into water courses, particularly in rural areas and informal settlements. This can be achieved through enhanced sanitation solutions, such as dry sanitation toilets, which are waste-contained alternatives to pit latrines.
From immediate relief to sustainable futures
Interventions will need to consider both immediate and long-term strategies. For short-term relief, containerised package plants can bolster sewage treatment facilities without the need for extensive infrastructure development, alleviating the strain on existing systems. Simultaneously, sanitation providers in the private sector can aid municipalities in implementing long-term solutions, including megalitre plans that feature efficiently packaged treatment plants. By adopting these smaller, cost-effective alternatives, it is possible to achieve the same capacity traditionally associated with larger concrete plants, in a fraction of the time to avert total system collapse and the impending health and economic catastrophes that would surely follow.
Netcare well on track with environmental strategy targets
Photo by Sungrow Emea on Unsplash
In a tangible step towards further reducing its carbon footprint, the Netcare Group has successfully agreed commercial terms for a Renewable Energy (RE) Supply Agreement with independent clean energy solutions provider NOA Group Trading (NOA).
Netcare chief executive officer Dr Richard Friedland noted that the development is a significant milestone in realising the Group’s environmental sustainability strategy, which has made considerable strides since its implementation in 2013.
“Improvement of our energy efficiency initiatives remains a key focus area of this strategy. Netcare has also committed to procuring 100% of its purchased electrical energy from renewable energy sources by 2030, supporting the Race to Zero global campaign with targets that exceed the requirements of the Science Based Target initiative (SBTi) aimed at limiting global warming.
“This transaction represents Phase 1 of achieving this aim and includes six of our facilities where RE will be wheeled through the electricity grid from a combination of wind and solar farms, covering up to 100% of energy consumption at these facilities. This represents approximately 11% of the Group’s total energy consumption which is currently being supplied by Eskom’s predominantly coal fired power stations.
“In combination with other initiatives already implemented under Netcare’s sustainability programme, this transaction will increase the proportion of Netcare’s total energy consumption that is derived from RE sources to around 26%,” he says.
Dr Friedland noted that Netcare’s management teams are actively working towards finding viable solutions to supply RE to the remaining municipal-connected sites in the Group while continuing to build on existing renewable energy initiatives. The Group’s environmental sustainability programme also continues to demonstrate an impressive return on investment to date, illustrating the commercial opportunities in environmentally conscious engineering.
According to Karel Cornelissen, chief executive officer of NOA Group, renewable energy will be wheeled through the national grid to the six designated Netcare facilities via the existing Eskom distribution transmission network and delivery of renewable energy to these facilities is expected to commence by the first quarter of 2026. “The agreement represents a significant step towards a clean-energy future by one of South Africa’s healthcare industry leaders, and we are pleased to partner with Netcare on this crucial advancement,” he says.
Netcare joined the Race to Zero global campaign in 2021 and was the first healthcare institution in Africa to do so. The campaign strives to rally leadership and support from businesses, cities, regions and investors for a healthy, resilient, zero carbon recovery that prevents future threats, creates jobs, and unlocks inclusive, sustainable growth.
“The devastation of climate change to the environment and among communities is already resulting in enormous hardship and tragedy not only in South Africa but around the world. We cannot sit idly by while this happens. Urgent action must be taken by implementing innovative solutions,” says Dr Friedland.
“During the past decade, Netcare has actively been engaged in several planned energy, waste and water management initiatives. This meaningful transaction is yet another step towards implementing appropriate green solutions while contributing towards a healthier environment for the people of South Africa in the decades to come and beyond,” he concludes.
Blood pressure among patients diagnosed with hypertension appeared to slightly increase and rates of systolic blood pressure being controlled during an outpatient visit appeared to slightly decrease during winter months, according to a new study presented at the American Heart Association’s Hypertension Scientific Sessions 2023.
Previous research has found that blood pressure varies with the seasons of the year, most of which is systolic blood pressure. The study authors sought to understand whether blood pressure control, defined in this study as less than 140/90mmHg among patients with hypertension, varied by season.
“Despite the smaller degree of systolic blood pressure variation in comparison to previous studies on seasonality in blood pressure, we were surprised to observe a large degree of change in blood pressure control between winter and summer months,” said lead study author Robert B. Barrett, a software engineer at the American Medical Association in Greenville, South Carolina. “Individuals with hypertension or values near the range of hypertension may benefit from periodic blood pressure monitoring and improvements in physical activity and nutritional patterns during winter months to offset adverse effects from seasonal blood pressure changes.”
The researchers reviewed electronic health records for 60 676 adults treated for hypertension between July 2018 and June 2023 at six health care centres. Each participant remained on their originally prescribed classes of antihypertensive drugs throughout the review period. The centres ranged from small health centres or clinics to large academic medical centres. Seasonal blood pressure readings were analysed to assess variations in blood pressure control during the northern hemisphere’s winter vs summer months (December through February vs June through August, respectively) as part of an American Medical Association-supported, quality-improvement program for clinicians and health care centres. Study participants were an average age of 62 years old; 52.3% identified as white race; 59.7% identified as female.
The analysis of the health records found that, on average, participants’ systolic blood pressure increased by up to 1.7mmHg in the winter months compared to the summer months. In addition, they found that blood pressure control rates decreased by up to 5% during the winter months.
Future directions for investigation might include analysing the frequency of heart disease and deaths during each season, the authors noted.
The study’s limitations include that the electronic health records did not capture a complete health history for each participant and that information collected for each patient was retrieved only from the institution where they were treated.
A new study from Aarhus University has shown that young people with mild asthma can experience inflammation and irritation from candles as well as cooking fumes. The results, published in Particle and Fibre Toxicology, suggest that asthma sufferers should try and reduce exposure, for example by opening kitchen windows while cooking.
For this randomised controlled double-blind exposure study, exposed 36 young asthmatics to three different exposures in the climate chambers at Aarhus University. They were exposed to emissions from cooking, emissions from burning candles and finally clean air. Each time, the participants were exposed for five hours under highly controlled conditions. Particles and gases were measured during exposures, and participants reported symptoms related to irritation and general well-being. Biomarkers in relation to airway and systemic inflammatory changes were assessed before exposure, immediately after exposure and again the next morning.
Karin Rosenkilde Laursen, a postdoc at the university’s Department of Public Health and co-author of the study, says:
“Our study shows that indoor air pollution caused by fumes from cooking and burning candles can lead to adverse health effects such as irritation and inflammation in young individuals with mild asthma. Among other things, we’ve found indications of DNA damage and signs of inflammation in the blood.”
When ovens are turned, pans put on the hob, or candles are lit, particulate matter and gases are produced, which can be inhaled. Previous studies have shown that these particles and gases can be detrimental to health. What sets this study apart is that the researchers have focused on the effects on young individuals with mild asthma, aged between 18 and 25, says Karin Rosenkilde Laursen:
“In the study, we observed that even very young individuals with mild asthma can experience discomfort and adverse effects if the room is not adequately ventilated during cooking or when burning candles. Young people are generally fitter and more resilient than older and middle-aged individuals. Therefore, it is concerning that we observed a significant impact from the particles on this particularly young age group.”
But not only people diagnosed with asthma need to keep an eye on the indoor climate, she says.
“Even though the study focused on young asthmatics, its findings are interesting and relevant for all of us. Winter is approaching, a time when we tend to light many candles and perhaps are less likely to open doors and windows while cooking. By prioritising a healthier indoor climate, even when we’re cosying up indoors, we may be able to help reduce the incidence of serious lung and cardiovascular diseases, as well as cancer.”
Karin Rosenkilde Laursen plans to follow up this study with another examining how emissions from cooking and candles affect healthy adults.
Researchers have detected significant levels of metals in the blood and urine among marijuana users, concluding that marijuana may be an important and under-recognised source of lead and cadmium exposure. This is among the first studies to report biomarker metal levels among marijuana users and most likely the largest study to date, that links self-reported marijuana use to internal measures of metal exposure, rather than just looking at metal levels in the cannabis plant. The results are published online in the journal Environmental Health Perspectives.
Measurements reported by participants for exclusive marijuana use compared to nonmarijuana-tobacco had significantly higher lead levels in blood (1.27ug/dL) and urine (1.21ug/g creatinine).
“Because the cannabis plant is a known scavenger of metals, we had hypothesised that individuals who use marijuana will have higher metal biomarker levels compared to those who do not use,” said first author Katelyn McGraw, postdoctoral researcher. “Our results therefore indicate marijuana is a source of cadmium and lead exposure.”
The researchers, from Columbia University Mailman School of Public Health, combined data from the National Health and Nutrition Examination Survey for the years 2005-2018, a biannual programme of studies designed to assess the health and nutritional status of adults and children in the U.S.
McGraw and colleagues classified the 7254 survey participants by use: non-marijuana/non-tobacco, exclusive marijuana, exclusive tobacco, and dual marijuana and tobacco use. Five metals were measured in the blood and 16 in urine.
The researchers used four NHANES variables to define exclusive marijuana and tobacco use: current cigarette smoking, serum cotinine levels, self-reported ever marijuana use, and recent marijuana use. Exclusive tobacco use was defined as individuals who either answered yes to ‘do you now smoke cigarettes, or if individuals had a serum cotinine level >10ng/mL.
The study found higher levels of cadmium (Cd) and lead (Pb) in blood and urine among participants reporting exclusive marijuana use compared to non-smokers. Cd and Pb levels were also higher in exclusive marijuana users who reported using marijuana within the last week. Cd biomarker levels were higher in those who smoked only marijuana than , either because of differences in frequency of use or differences in Cd levels in the tobacco and cannabis plants themselves. However, blood and urinary Pb levels among exclusive marijuana users and exclusive tobacco users were similar. Dual marijuana and tobacco users also had higher levels of Cd and Pb compared with non-smokers.
These observations marijuana use is an important and underrecognised source of Cd and Pb exposure independent of tobacco use, the researchers concluded.
Marijuana is the third most commonly used drug in the world behind tobacco and alcohol. As of 2022, 21 states and Washington D.C., covering more than 50 percent of the U.S. population, have legalised recreational use of marijuana; and medical marijuana is legal in 38 states and Washington D.C. However, because marijuana is still illegal at the federal level, regulation of contaminants in all cannabis-containing products remains piecemeal and there has been no guidance from federal regulatory agencies like the FDA or EPA. As of 2019, 48.2 million people, or 18% of Americans, report using marijuana at least once in the last year.
While 28 states regulate inorganic arsenic, cadmium, lead, and total mercury concentrations in marijuana products, regulation limits vary by metal and by state.
“Going forward, research on cannabis use and cannabis contaminants, particularly metals, should be conducted to address public health concerns related to the growing number of cannabis users,” said Tiffany R. Sanchez, PhD, assistant professor of environmental health sciences at Columbia Public Health, and senior author.
