Category: Environmental Effects

Living Near Fracking Sites Increases Childhood Leukaemia Risk

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Children living near unconventional oil and gas (UOG) or ‘fracking’ developments at birth had a 2–3 times greater risk of leukaemia diagnoses between 2 and 7 years old, researchers have found.

Their study, published in the journal Environmental Health Perspectives, included nearly 2500 Pennsylvania children, 405 of whom were diagnosed with acute lymphoblastic leukaemia (ALL).

ALL arises from mutations to lymphoid immune cells. Although long-term survival rates are high, survivors may have long-term health risks and psychological issues. Unconventional oil and gas development, more commonly referred to as fracking (short for hydraulic fracturing), is a method for extracting gas and oil from shale rock. The process involves high-pressure injection of water, sand, and chemicals into bedrock to release oil or gas for extraction.

For communities living nearby, UOG development can pose a number of potential threats. As well as air pollution from vehicles and construction, there is also water pollution from hydraulic fracturing or spills of wastewater. Hundreds of chemicals have been reportedly used in UOG injection water or detected in wastewater, some of which are known or suspected carcinogens. The lack of data about this has given rise to concerns over the proximity of UOG to residential areas.

“Unconventional oil and gas development can both use and release chemicals that have been linked to cancer, so the potential for children living near UOG to be exposed to these chemical carcinogens is a major public health concern,” said the study’s senior author, Nicole Deziel, associate professor of epidemiology at the Yale School of Public Health.

“Studies of UOG exposure and cancer are extremely few in number. We set out to conduct a high-quality study to further investigate this potential relationship,” added Cassandra Clark, the study’s first author and a postdoctoral associate at the Yale Cancer Center. “Our results indicate that exposure to UOG may be an important risk factor for ALL, particularly for children exposed in utero.”

Oil and gas-related chemicals exposure could be through drinking water, the researchers found. The watershed, the zone from which a drinking water well serving their home would likely draw water, were compared with the distance from the home to the nearest of those UOG wells. UOG wells falling within the watershed area are expected to be more likely to impact the home’s drinking water supply, they said.

This work adds to a growing body of literature on UOG exposure and children’s health used to inform policy, such as setback distances (the required minimum distance between a private residence or other sensitive location and a UOG well). Current setback distances are the subject of much debate in the United States, with some calling for setback distances to be lengthened to more than 305m and as far as 1000m. The allowable setback in Pennsylvania, where the study was conducted, is 152m.

“Our findings of increased risk of ALL at distances of two kilometres or more from UOG operations, in conjunction with evidence from numerous other studies, suggest that existing setback distances, which may be as little as 150 feet (50m), are insufficiently protective of children’s health,” Clark said. “We hope that studies like ours are taken into account in the ongoing policy discussion around UOG setback distances.”

Source: Yale University

Increase in Excessively Hot Nights Will Raise Mortality Rate

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With the number of excessively hot nights expected to double due to climate change, it is predicted that their associated mortality rate will rise by up to 60% by the end of the century, according to the latest research published in published in The Lancet Planetary Health.

Ambient heat during the night may interrupt the normal physiology of sleep, leading to immune system damage and a higher risk of cardiovascular disease, chronic illnesses, inflammation and mental health conditions. The average intensity of hot night events will nearly double by 2090, from 20.4℃ to 39.7℃ across 28 cities from east Asia, increasing the burden of disease due to excessive heat that disrupts normal sleeping patterns.

This is the first study to estimate the impact of hotter nights on climate change-related mortality risk. The findings show that the burden of mortality could be significantly higher than estimated by average daily temperature increase, suggesting that warming from climate change could have a troubling impact, even under restrictions from the Paris Climate Agreement.

“The risks of increasing temperature at night were frequently neglected,” said study co-author Yuqiang Zhang, PhD, a climate scientist in the Department of Environmental Sciences and Engineering at the Gillings School. “However, in our study, we found that the occurrences of hot night excess are projected to occur more rapidly than the daily mean temperature changes. The frequency and mean intensity of hot nights would increase more than 30% and 60% by the 2100s, respectively, compared with less than 20% increase for the daily mean temperature.”

The team estimated the mortality due to excess heat in 28 cities in China, South Korea and Japan between 1980 and 2015 and applied it to two climate change modelling scenarios that aligned with carbon-reduction scenarios adapted by the respective national governments.

Through this model, the team was able to estimate that between 2016 and 2100, the risk of death from excessively hot nights would increase nearly six-fold. This prediction is much higher than the mortality risk from daily average warming suggested by climate change models.

“From our study, we highlight that, in assessing the disease burden due to non-optimum temperature, governments and local policymakers should consider the extra health impacts of the disproportional intra-day temperature variations. A more complete health risk assessment of future climate change can help policymakers for better resource allocation and priority setting,” said Haidong Kan, PhD, who is a professor at Fudan University in China and the study’s corresponding author.

In this study, the authors also found that regional differences in temperature accounted for many of the variances in nighttime temperature, and areas with the lowest average temperature were projected to have the largest warming potential.

“To combat the health risk raised by the temperature increases from climate change, we should design efficient ways to help people adapt,” said Dr Zhang. “Locally, heat during the night should be taken into account when designing the future heatwave warning system, especially for vulnerable populations and low-income communities who may not be able to afford the additional expense of air conditioning. Also, stronger mitigation strategies, including global collaborations, should be considered to reduce future impacts of warming.”

Since the study only included 28 cities from three countries, Dr Zhang said that “extrapolation of these results to the whole East Asia region or other regions should be cautious. Currently, based on these findings, authors are trying to extend the analysis to a global dataset. Then we could have a global picture of the deadly nighttime heat on health under climate change scenarios.”

Source: University of North Carolina at Chapel Hill

Sun Exposure Triggers Appetite in Men but not Women

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A new study from Tel Aviv University reveals that solar exposure increases appetite in males – but not in females. It is the first gender-dependent medical study ever conducted on UV exposure, and reveals a molecular connection between UV exposure and appetite.

Skin as a regulator of appetite

The groundbreaking study was led by Prof. Carmit Levy and PhD student Shivang Parikh and published in Nature Metabolism.

The study was based on epidemiological data collected in a year-long survey about the eating habits of approximately 3000 Israelis of both sexes, including self-reports from students who had spent time in the sun, combined with the results of a genetic study in a lab model. The findings identify the skin as a primary regulator of metabolism in both lab models and humans, influencing appetite.

In females, oestrogen blocks appetite after sun exposure

The study unravels the differences between males and females in the activation of the metabolic mechanism. The researchers explain that in males of both animal species and humans, sun exposure activates a protein called p53, to repair any DNA damage in the skin that might have been caused by the exposure. The activation of p53 signals the body to produce a hormone called ghrelin, which stimulates the appetite.

In females, oestrogen blocks the interaction between p53 and ghrelin, and consequently does not catalyse the urge to eat following exposure to the sun.

Males and females, have differences in metabolism which impacts both their health and their behaviour. However, so far it has not been established whether the two sexes respond differently to environmental triggers such as exposures to the sun’s UV radiation.

“We examined the differences between men and women after sun exposure and found that men eat more than women because their appetite has increased. Our study was the first gender-dependent medical study ever conducted on UV exposure, and for the first time, the molecular connection between UV exposure and appetite was deciphered. Gender-dependent medical studies are particularly complex, since twice the number of participants is required to find statistically significant differences,” explained Prof Levy.

“As humans, we have cast off our fur and consequently, our skin, the largest organ in our body, is exposed to signals from the environment. The protein p53, found in the skin, repairs damage to the DNA caused by sun exposure, but it does more than that. It signals to our bodies that winter is over, and we are out in the sun, possibly in preparation for the mating season. Our results provide an encouraging basis for more research, on both human metabolism and potential UV-based therapies for metabolic diseases and appetite disorders,” Prof Levy concluded.

Source: Tel Aviv University

Maternal Phthalates Exposure Increases Preterm Birth Risk

pregnant woman holding her belly
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A National Institutes of Health study has found that pregnant women who were exposed to multiple phthalates during pregnancy had an increased risk of preterm birth. The most significant correlation was for a phthalate most commonly used in nail polish and cosmetics.

Used in a great variety of products such as cosmetics and food packaging, phthalates are endocrine-disrupting chemicals that are known to have a wide range of health effects on humans. This especially true of children, due to their impact on the developmental system, as well as the reproductive system.

Researchers analysed data from more than 6000 pregnant women in the US, and found that women with higher concentrations of several phthalate metabolites in their urine had increased risks of preterm birth.

“Having a preterm birth can be dangerous for both baby and mom, so it is important to identify risk factors that could prevent it,” said epidemiologist Kelly Ferguson, PhD, the senior author on the study published in JAMA Pediatrics.

Data from 16 US studies that included individual participant data on prenatal urinary phthalate metabolites (representing exposure to phthalates) as well as the timing of delivery. Researchers analysed data from a total of 6045 pregnant women who delivered between 1983-2018, 9% of whom delivered preterm. Phthalate metabolites were detected in more than 96% of urine samples.

Exposure to four of the 11 phthalates found in the pregnant women was associated with a 14–16% greater probability of having a preterm birth. The most consistent findings were for exposure to a phthalate that is used commonly in personal care products like nail polish and cosmetics.

Using statistical models to simulate interventions that reduce phthalate exposures, the researchers found that reducing the mixture of phthalate metabolite levels by 50% could prevent preterm births by 12% on average. Interventions targeting behaviours, such as trying to select phthalate-free personal care products (if listed on label), voluntary actions from companies to reduce phthalates in their products, or changes in standards and regulations could contribute to exposure reduction and protect pregnancies.

“It is difficult for people to completely eliminate exposure to these chemicals in everyday life, but our results show that even small reductions within a large population could have positive impacts on both mothers and their children,” said Barrett Welch, PhD, first author on the study.

Eating fresh, home-cooked food, avoiding processed food that comes in plastic containers or wrapping, and selecting fragrance-free products or those labeled ‘phthalate-free’, are examples of things people can do that may reduce their exposures. Changes to the amount and types of products that contain phthalates could also reduce exposures.

The researchers are undertaking further studies to better understand the mechanisms behind how phthalates affect pregnancy and to find ways for mothers to reduce their exposures.

Source: National Institutes of Health

Sunlight Might Cause New-onset Lupus

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While a large, long-running epidemiologic study was unable to conclude that ultraviolet (UV) radiation in sunlight can cause new-onset systemic lupus erythematosus (SLE), trends in the data suggested that it could, according to findings reported in the journal Arthritis Care & Research.

Participants in the  who were in the upper tertile (third) of estimated UV-B exposure had 28% higher rates of incident SLE during follow-up.

Similar numerical increases in risk with high estimated UV-B exposure were seen for specific lupus subtypes and manifestations, such as SLE with photosensitivity or with anti-Ro/La antibodies, which also fell short of statistical significance, they reported

The study’s relatively small number of new-onset SLE cases – only 297 out of about six million person-years of data – was the likely reason for the broad confidence intervals. The study did also find one lupus subtype with a statistically significant association with UV-B exposure: SLE with malar rash (HR 1.62 for top versus bottom tertile, 95% CI 1.04-2.52).

“We found no overall association between high UV radiation exposure and risk of overall SLE in these large cohorts of women prospectively followed for many years prior to SLE onset,” the researchers acknowledged.

“However, cumulative average UV radiation exposure in the highest tertile was associated with non-significant but suggestive increased risk of the subtype of SLE presenting with cutaneous antibodies, including anti-Ro and/or anti-La antibodies, and/or cutaneous involvement, including malar rash (acute cutaneous lupus) and/or photosensitivity, which tend to co-occur, and are biologically plausible,” they stated.

Photosensitivity is a hallmark of lupus, and sunlight exposure is known to cause disease flareups in people with established SLE. Among the 297 cases of incident SLE that developed in NHS participants, 58% included photosensitivity. Other risk factors include smoking and exposure to silica. Exposure to strong sunlight might be another one, since UV radiation disrupts skin keratinocytes, releasing antigens that could trigger autoimmune attack.

The decades-long American Nurses’ Health Study (NHS) I and II has the medical records of 240 000 participants, mostly female, who completed detailed questionnaires.

However, new-onset SLE is rare enough that, even with that many participants, there weren’t enough cases to be sure whether risk increases in the 30%-50% range were real.

Other major limitations included having to estimate UV exposure from participants’ residence, race serving as an inexact proxy of skin tone, and no data on sunburn history or sunscreen use.

Source: MedPage Today

River Pollution from Pharmaceutical Production is Widespread

Pills and tablets
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Pharmaceutical ingredients from both prescription and over-the-counter drugs find their way into the environment during their production, use and disposal. They readily contaminate bodies of surface water such as rivers and lakes. Results from a recent study published in Environmental Toxicology and Chemistry indicate that pharmaceutical pollution is a problem that is affecting the world’s rivers. 

Approximately 43.5% of the 1052 locations that were assessed in the study across 104 countries had concerning concentrations of pharmaceutical ingredients. Twenty-three pharmaceutical ingredients occurred at concentrations that exceeded ‘safe’ concentrations, including substances from drug classes including antidepressants, antimicrobials, antihistamines, benzodiazepines, and painkillers.   

“This is the first truly global assessment of the impacts of single pharmaceuticals and mixtures of pharmaceuticals in riverine systems,” said corresponding author Alejandra Bouzas-Monroy, a PhD student at the University of York. “Our findings show that a very high proportion of rivers around the world are at threat from pharmaceutical pollution. We should therefore be doing much more to reduce the emissions of these substances into the environment.”  

Source: EurekAlert!

PFAS and Phthalates Linked to Reduced Bone Density in Teen Boys

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Per- and polyfluoroalkyl substances (PFAS) and phthalates (two types of endocrine-disrupting chemicals) may be associated with lower areal bone mineral density (aBMD) in teenage boys, according to a new study published in the Journal of Clinical Endocrinology and Metabolism.

Endocrine disrupting chemicals (EDCs) and potential EDCs are mostly man-made found in various materials. By interfering with the body’s endocrine system, endocrine disruptors produce adverse developmental, reproductive, neurological, and immune effects in humans, abnormal growth patterns and neurodevelopmental delays in children. These include per- and polyfluoroalkyl substances (PFAS) are used in non-stick pots and pans, clothing and food packaging, and are increasingly being found in US water supplies. Phthalates are used in medical devices, personal care products, food processing and children’s toys.

“Adolescence is an important time when our bodies build up bone. Almost all US children and adolescents are exposed to PFAS and phthalates, but few studies have looked at how these chemicals could be impacting our bone health,” said Abby F. Fleisch, MD, MPH, of the Maine Medical Center Research Institute and Maine Medical Center. “Our research found an association between certain PFAS and phthalates and reduced bone mineral density in adolescent males. Because bone accrual primarily occurs during adolescence, if replicated, this finding may have implications for lifelong bone health.”

The researchers accessed data on urine and blood samples from 453 boys and 395 girls from the National Health and Nutrition Examination Survey (NHANES). Participants were on average 15.1 years old, and found that higher levels of PFAS and phthalates may be associated with lower aBMD in adolescent males. The same effect was not found in girls; rather a slight increase in aBMD was observed for certain PFAS and phthalates.

The researchers noted that bone mineral density tracks across a lifetime, so if the same results are seen in longitudinal cohorts, this finding may have implications for lifelong skeletal health.

Source: The Endocrine Society

New Evidence-based Recommendations for Light Exposure

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For the first time, a set of recommendations have been drawn up to provide guidance for human exposure to light throughout the day and at nighttime, based on the amount of blue light in the environment. The recommendations are detailed in PLOS Biology.

Modern lifestyles, with 24-hour access to electric light and reduced exposure to natural daylight, can disrupt sleep and negatively impact health, well-being, and productivity. A new report in PLOS Biology addresses the issue of exactly how bright lighting should be during the day and in the evening to support healthy body rhythms, restful sleep, and daytime alertness.

An international body of leading scientific experts was brought together to draw up the first evidence-based, consensus recommendations for healthy daytime, evening, and nighttime light exposure. These recommendations provide much needed guidance to the lighting and electronics industries to aid the design of healthier environments and to improve how we light our workplaces, public buildings, and homes.

The new report took on a key question – how to properly measure the extent to which different types of lighting might influence circadian rhythms and sleep patterns. Light affects these patterns via a specialised type of cell in the eye that uses a light sensitive protein, melanopsin, that is distinct from the opsin in the rods and cones that support vision (and upon which traditional ways of measuring “brightness” are based). Since melanopsin is most sensitive to blue-cyan light, the new recommendations used a newly-developed light measurement standard tailored to this unique property: melanopic equivalent daylight illuminance. Analysis of data from a variety of studies proved that this new measurement approach could provide a reliable way of predicting the effects of light on human physiology and body rhythms, and so could form the basis of widely applicable and meaningful recommendations.

A crucial next step will be to integrate the recommendations into formal lighting guidelines, which currently focus on visual requirements rather than effects on health and well-being. Additionally, advances in LED lighting technology and the availability of low-cost light sensors are expected to increase the ease with which individuals can optimise their personal light exposure to best support their own circadian rhythms in line with the new recommendations.

Professor Timothy Brown, who brought the international exports together for the report added: “These recommendations provide the first scientific consensus, quantitative, guidance for appropriate daily patterns of light exposure to support healthy body rhythms, nighttime sleep and daytime alertness. This now provides a clear framework to inform how we light any interior space ranging from workplaces, educational establishments and healthcare facilities to our own homes.”

Source: Science Daily

Lead Exposure Lowered IQ of Americans Born Up to 1996

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A new study calculates that exposure to car exhaust from leaded gas during childhood lowered the IQ levels of about half the population of Americans alive today.

The findings suggest that Americans born before 1996 may now be at greater risk for lead-related health problems, such as faster ageing of the brain. Leaded petrol was banned in the US in 1996, but anyone born in the US before the end of that era, and especially those at the peak of its use in the 1960s and 1970s, had worryingly high lead exposures as children, the researchers said. In South Africa, leaded petrol was only banned at the end of 2005.

The study’s findings were published in Proceedings of the National Academy of Sciences.

Lead is a neurotoxin that can enter the bloodstream via a number of routes and there is no safe level of exposure at any point in life. Young children are especially vulnerable to lead’s ability to impair brain development and lower cognitive ability.

“Lead is able to reach the bloodstream once it’s inhaled as dust, or ingested, or consumed in water,” said study co-author Aaron Reuben, a PhD candidate in clinical psychology. “In the bloodstream, it’s able to pass into the brain through the blood-brain barrier, which is quite good at keeping a lot of toxicants and pathogens out of the brain, but not all of them.”

To answer the complex question of how more than 70 years of leaded petrol use may have left a permanent mark on human health, Reuben and co-authors Michael McFarland and Mathew Hauer, both professors of sociology at Florida State University, opted for a fairly simple strategy.

Using publicly available data on US childhood blood-lead levels, leaded-gas use, and population statistics, they determined the likely lifelong burden of lead exposure carried by every American alive in 2015. From this data, they estimated lead’s assault on our intelligence by calculating IQ points lost from leaded gas exposure as a proxy for its harmful impact on public health – a result which stunned the researchers.

“I frankly was shocked,” Prof McFarland said. “And when I look at the numbers, I’m still shocked even though I’m prepared for it.”

As of 2015, more than 170 million Americans (more than half of the U.S. population) had clinically concerning levels of lead in their blood as children, likely resulting in lower IQs and putting them at higher risk for other long-term health impairments, such as reduced brain size, greater likelihood of mental illness, and increased cardiovascular disease in adulthood.

Leaded gasoline consumption rose rapidly in the early 1960s and peaked in the 1970s. As a result, Reuben and his colleagues found that essentially everyone born during those two decades are all but guaranteed to have been exposed to pernicious levels of lead from car exhaust.

Even more startling was lead’s toll on intelligence: childhood lead exposure may have blunted America’s cumulative IQ score by an estimated 824 million points – nearly three points per person on average. The researchers calculated that at its worst, people born in the mid-to-late 1960s may have lost up to six IQ points, and children registering the highest levels of lead in their blood, eight times the current minimum level to initiate clinical concern, fared even worse, potentially losing more than seven IQ points on average.

While the loss of a few IQ points may seem negligible, the authors note that these changes are dramatic enough to potentially shift people with below-average cognitive ability (IQ score less than 85) to being classified as having an intellectual disability (IQ score below 70).

Prof McFarland is continuing by analysing the racial disparities of childhood lead exposure, hoping to highlight the health inequities suffered by Black children, who were exposed more often to lead and in greater quantities than white children.

Reuben’s next step will be to examine the long-term consequences of past lead exposure on brain health in old age, based on evidence showing that adults with high childhood lead exposure may experience accelerated brain aging.

“Millions of us are walking around with a history of lead exposure,” Reuben said. “It’s not like you got into a car accident and had a rotator cuff tear that heals and then you’re fine. It appears to be an insult carried in the body in different ways that we’re still trying to understand but that can have implications for life.”

Source: Duke University

Climate Change Will Increase Deaths Linked to Extreme Temperatures

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The death rate linked to extreme temperatures will increase significantly under global warming of 2°C, with even steeper rises for each degree of warming, finds a report published in Environmental Research Letters.

With a warming scenario of just 2°C from pre-industrial levels, temperature-related mortality in England and Wales during the hottest days of the year will increase by 42%. This means an increase from present-day levels of around 117 deaths per day, averaged over the 10 hottest days of the year, to around 166 deaths per day. The findings underline the importance of keeping global warming levels to below 2°C.

At current global warming levels of around 1.21°C there would be a slight decrease in temperature-related mortality in winter and a minimal net effect in summer, meaning that overall, at this level of warming we see a slight decrease in temperature-related mortality rate.

The researchers assessed the impact of climate change on mortality rates England and Wales, specifically risk from heat in summer and cold in winter. They found that as the global mean temperature increases, temperature-related mortality in summer will increase at a much faster, non-linear rate.

The rate of increase particularly speeds up at 2°C of warming, with a much higher risk appearing beyond 2.5°C. The researchers say that 3°C warming could lead to a 75% increase in mortality risk during heatwaves.

The relationship between temperature and mortality on a graph is roughly U-shaped, meaning that at extremely high temperatures, mortality risk increases sharply for each degree rise of daily mean temperature.

The rate in winter will continue to decrease, although this leaves out extreme weather events such as storms.

Lead author Dr Katty Huang said: “The increase in mortality risk under current warming levels is mainly notable during heatwaves, but with further warming, we would see risk rise on average summer days in addition to escalating risks during heatwaves. What this means is that we shouldn’t expect past trends of impact per degree of warming to apply in the future. One degree of global warming beyond 2°C would have a much more severe impact on health in England and Wales than one degree warming from pre-industrial levels, with implications for how the NHS can cope.”

In England and Wales, temperature is associated with around 9% of total population mortality, meaning that 9% of all deaths during 2021 could be associated with the temperature. Most of those deaths are related to the side effects of cold weather.

The team analysed the 2018 UK Climate Projections (UKCP18) with data on present-day temperature and mortality in order to predict changes in temperature-related mortality relative to degrees of global warming.

In order to isolate the effects of global warming on mortality risk, the researchers looked at the potential impact for the current population, and not attempting to predict future age distributions and medical conditions.

Project lead Professor Andrew Charlton-Perez said: “As the Intergovernmental Panel on Climate Change impacts report recently showed, it is increasingly common to examine how different levels of mean global warming raise the risk of significant harm to people and society. Our study shows that because death rates will go up significantly if countries experience very high temperatures, limiting the average global rise in temperatures is likely to have substantial benefits for the overall health of the population.”

Source: University College London