Category: Environmental Effects

Categories : Cancer Environmental EffectsTags :

Study Reveals Links between Many Pesticides and Prostate Cancer

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US county-level data point to specific pesticides that may increase prostate cancer incidence and death.

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Researchers have identified 22 pesticides consistently associated with the incidence of prostate cancer in the United States, with four of the pesticides also linked with prostate cancer mortality. The findings are published by Wiley online in CANCER, a peer-reviewed journal of the American Cancer Society.

To assess county-level associations of 295 pesticides with prostate cancer across counties in the United States, investigators conducted an environment-wide association study, using a lag period between exposure and prostate cancer incidence of 10–18 years to account for the slow-growing nature of most prostate cancers. The years 1997–2001 were assessed for pesticide use and 2011–2015 for prostate cancer outcomes. Similarly, 2002–2006 were analysed for pesticide use and 2016–2020 for outcomes.

Among the 22 pesticides showing consistent direct associations with prostate cancer incidence across both time-based analyses were three that had previously been linked to prostate cancer, including 2,4-D, one of the most frequently used pesticides in the United States. The 19 candidate pesticides not previously linked to prostate cancer included 10 herbicides, several fungicides and insecticides, and a soil fumigant.

Four pesticides that were linked to prostate cancer incidence were also associated with prostate cancer mortality: three herbicides (trifluralin, cloransulam-methyl, and diflufenzopyr) and one insecticide (thiamethoxam). Only trifluralin is classed by the Environmental Protection Agency as a “possible human carcinogen,” whereas the other three are considered “not likely to be carcinogenic” or have evidence of “non-carcinogenicity.”

“This research demonstrates the importance of studying environmental exposures, such as pesticide use, to potentially explain some of the geographic variation we observe in prostate cancer incidence and deaths across the United States,” said lead author Simon John Christoph Soerensen, MD, of Stanford University School of Medicine. “By building on these findings, we can advance our efforts to pinpoint risk factors for prostate cancer and work towards reducing the number of men affected by this disease.”

Source: Wiley

Categories : Environmental Effects NeurologyTags :

PFAS Influence the Development and Function of the Brain

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Some per- and polyfluoroalkyl substances (PFAS) are poorly degradable and are also known as “forever chemicals”. They adversely affect health and can lead to liver damage, obesity, hormonal disorders, and cancer. A research team from the Helmholtz Centre for Environmental Research (UFZ) has investigated the effects of PFAS on the brain.

Using a combination of modern molecular biology methods and the zebrafish model, the researchers revealed the mechanism of action and identified the genes involved, which are also present in humans. The test procedure developed at the UFZ could be used for the risk assessment of other neurotoxic chemicals. The study was recently published in Environmental Health Perspectives. 

Because of their special properties – heat resistance, water and grease repellence, and high durability – PFAS are used in many everyday products (eg, cosmetics, outdoor clothing, and coated cookware). But it is precisely these properties that make them so problematic. “Because some PFAS are chemically stable, they accumulate in the environment and enter our bodies via air, drinking water, and food”, says UFZ toxicologist Prof Dr Tamara Tal. Even with careful consumption, it is nearly impossible to avoid this group of substances, which has been produced since the 1950s and now includes thousands of different compounds. “There is a great need for research, especially when it comes to developing fast, reliable, and cost-effective test systems for assessing the risks of PFAS exposure”, says Tal. So far, the environmental and health consequences have been difficult to assess.

In their current study, the researchers investigated how PFAS exposure affects brain development. To do this, they used the zebrafish model, which is frequently used in toxicology research. One advantage of this model is that around 70% of the genes found in zebrafish (Danio rerio) are also found in humans. The findings from the zebrafish model can therefore likely be transferred to humans. In their experiments, the researchers exposed zebrafish to two substances from the PFAS group (PFOS and PFHxS), which have a similar structure. The researchers then used molecular biological and bioinformatic methods to investigate which genes in the brains of the fish larvae exposed to PFAS were disrupted compared to the control fish, which were not exposed. “In the zebrafish exposed to PFAS, the peroxisome proliferator-activated receptor (ppar) gene group, which is also present in a slightly modified form in humans, was particularly active”, says Sebastian Gutsfeld, PhD student at the UFZ and first author of the study. “Toxicity studies have shown this to be the case as a result of exposure to PFAS – albeit in the liver. We have now also been able to demonstrate this for the brain”.

But what consequences does an altered activity of the ppar genes triggered by PFAS exposure have for brain development and behaviour of zebrafish larvae? The researchers investigated this in further studies using the zebrafish model. Using CRISPR/Cas9 ‘gene scissors’ the researchers were able to “selectively cut individual or several ppar genes and prevent them from functioning normally”, explains Gutsfeld. “We wanted to find out which ppar genes are directly linked to a change in larval behaviour triggered by PFAS exposure”. Proof of the underlying mechanism was directly provided. In contrast to genetically unaltered zebrafish, the knockdown fish in which the gene scissors were used should not show any behavioural changes after exposure to PFAS.

The two behavioural endpoints

In one series of experiments, the researchers continuously exposed zebrafish to PFOS or PFHxS during their early developmental phase between day one and day four and in another series of experiments only on day five. On the fifth day, the researchers then observed swimming behaviour. They used two different behavioural endpoints for this purpose. In one endpoint, swimming activity was measured during a prolonged dark phase. PFAS-exposed fish swam more than fish not exposed to PFAS, whether continuously exposed to PFAS during brain development or shortly before the behaviour test. Interestingly, hyperactivity was only present when the chemical was around. When the researchers removed PFOS or PFHxS, hyperactivity subsided. In the second endpoint, the startle response after a dark stimulus was measured. “In zebrafish exposed to PFOS for four days, we observed hyperactive swimming behaviour in response to the stimulus”, says Gutsfeld. In contrast, zebrafish only exposed to PFOS or PFHxS on the fifth day did not have a hyperactive startle response.

Based on these responses, the researchers conclude that PFOS exposure is associated with abnormal consequences – particularly during sensitive developmental phases of the brain. Using knockdown zebrafish, the researchers identified two genes from the ppar group that mediate the behaviour triggered by PFOS. 

“Because these genes are also present in humans, it is possible that PFAS also have corresponding effects in humans”, concludes Tal. The scientists working with Tal want to investigate the neuroactive effects of other PFAS in future research projects and expand the method so that it can ultimately be used to assess the risk of chemicals in the environment, including PFAS.

Source: Helmholtz Centre for Environmental Research – UFZ

Categories : Environmental Effects Substance UseTags :

Pharmaceutical and Illicit Drugs Contaminating New York’s Rivers

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In research published in Environmental Toxicology & Chemistry, investigators sampled water from 19 locations across the Hudson and East Rivers in 2021 and 2022 to identify and quantify the prescribed pharmaceuticals and drugs of abuse that are making their way into New York City’s rivers and to determine the source of these pollutants.

Metoprolol and atenolol (blood pressure medications), benzoylecgonine (the main metabolite of cocaine), methamphetamine (a stimulant), and methadone (an opioid) were the most prevalent drugs, present in more than 60% of water samples.

More drugs and higher concentrations were detected in water contaminated by Enterococci (bacteria that live in the intestinal tract) and after rainfall, indicating an impact from sewer overflow. However, the presence of drugs in clean water and during periods of dry weather indicated that wastewater treatment plant discharge may also contribute to the presence of drugs in rivers.

“This study shows how pharmaceuticals and drugs of abuse enter the New York City aquatic environment, highlighting the necessity of improving the current water management system,” said corresponding author Marta Concheiro-Guisan, PharmD, PhD, of the John Jay College of Criminal Justice.

Source: Wiley

Categories : Cardiovascular Disease Environmental EffectsTags :

Risk of Cardiovascular Disease Linked to Arsenic in Water

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Long term exposure to arsenic in water may increase cardiovascular disease and especially heart disease risk even at exposure levels below the US regulatory limit (10µg/L) according to a new study in Environmental Health Perspectives. This is the first study to describe exposure-response relationships at concentrations below the current regulatory limit and substantiates that prolonged exposure to arsenic in water contributes to the development of ischaemic heart disease.

The researchers, from Columbia University Mailman School of Public Health, compared various time windows of exposure, finding that the previous decade of water arsenic exposure up to the time of a cardiovascular disease event contributed the greatest risk.

“Our findings shed light on critical time windows of arsenic exposure that contribute to heart disease and inform the ongoing arsenic risk assessment by the EPA. It further reinforces the importance of considering non-cancer outcomes, and specifically cardiovascular disease, which is the number one cause of death in the US and globally,” said Danielle Medgyesi, a doctoral Fellow in the Department of Environmental Health Sciences at Columbia Mailman School. “This study offers resounding proof of the need for regulatory standards in protecting health and provides evidence in support of reducing the current limit to further eliminate significant risk.”

According to the American Heart Association and other leading health agencies, there is substantial evidence that arsenic exposure increases the risk of cardiovascular disease. This includes evidence of risk at high arsenic levels (> 100µg/L) in drinking water. The U.S. Environmental Protection Agency reduced the maximum contaminant level (MCL) for arsenic in community water supplies (CWS) from 50µg/L to 10µg/L beginning in 2006. Even so, drinking water remains an important source of arsenic exposure among CWS users. The natural occurrence of arsenic in groundwater is commonly observed in regions of New England, the upper Midwest, and the West, including California.

To evaluate the relationship between long-term arsenic exposure from CWS and cardiovascular disease, the researchers used statewide healthcare administrative and mortality records collected for the California Teachers Study cohort from enrollment through follow-up (1995-2018), identifying fatal and nonfatal cases of ischemic heart disease and cardiovascular disease. Working closely with collaborators at the California Office of Environmental Health Hazard Assessment (OEHHA), the team gathered water arsenic data from CWS for three decades (1990-2020).

The analysis included 98 250 participants, 6119 ischaemic heart disease cases and 9,936 CVD cases. Excluded were those 85 years of age or older and those with a history of CVD at enrolment. Similar to the proportion of California’s population that relies on CWS (over 90%), most participants resided in areas served by a CWS (92%). Leveraging the extensive years of arsenic data available, the team compared time windows of relatively short-term (3-years) to long-term (10-years to cumulative) average arsenic exposure. The study found decade-long arsenic exposure up to the time of a cardiovascular disease event was associated with the greatest risk, consistent with a study in Chile finding peak mortality of acute myocardial infarction around a decade after a period of very high arsenic exposure. This provides new insights into relevant exposure windows that are critical to the development of ischemic heart disease.

Nearly half (48%) of participants were exposed to an average arsenic concentration below California’s non-cancer public health goal < 1 µg/L. In comparison to this low-exposure group, those exposed to 1 to < 5 µg/L had modestly higher risk of ischaemic heart disease, with increases of 5 to 6%. Risk jumped to 20% among those in the exposure ranges of 5 to < 10 µg/L (or one-half to below the current regulatory limit), and more than doubled to 42% for those exposed to levels at and above the current EPA limit ≥ 10µg/L. The relationship was consistently stronger for ischemic heart disease compared to cardiovascular disease, and no evidence of risk for stroke was found, largely consistent with previous research and the conclusions of the current EPA risk assessment.

These results highlight the serious health consequences not only when community water systems do not meet the current EPA standard but also at levels below the current standard. The study found a substantial 20% risk at arsenic exposures ranging from 5 to < 10 µg/L which affected about 3.2% of participants, suggesting that stronger regulations would provide significant benefits to the population. In line with prior research, the study also found higher arsenic concentrations, including concentrations above the current standard, disproportionally affect Hispanic and Latina populations and residents of lower socioeconomic status neighbourhoods.

“Our results are novel and encourage a renewed discussion of current policy and regulatory standards,” said Tiffany Sanchez, senior author. “However, this also implies that much more research is needed to understand the risks associated with arsenic levels that CWS users currently experience. We believe that the data and methods developed in this study can be used to bolster and inform future studies and can be extended to evaluate other drinking water exposures and health outcomes.”

Source: Columbia University’s Mailman School of Public Health

Categories : Environmental EffectsTags :

The More Chemicals, the More their Neurotoxic Effects Add Up

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Chemicals are omnipresent today: they enter our bodies through food, air or the skin. But how do these complex mixtures of chemicals affect our health? In a study published in the journal Science, a research team from the Helmholtz Centre for Environmental Research (UFZ) has shown that chemicals that occur in complex mixtures and in concentration ratios as found in humans act together. Even if the concentrations of the individual substances were each below the effect threshold, the chemicals in the mixture showed a cumulative neurotoxic effect.

For their investigations, they used blood samples from pregnant women from the LiNA mother-child study (lifestyle and environmental factors and their influence on the newborn allergy risk), which has been running at the UFZ since 2006. 

In our everyday lives, we are exposed to a wide variety of chemicals that are distributed and accumulate in our bodies. These are highly complex mixtures that can affect bodily functions and our health,” says Prof Beate Escher, Head of the UFZ Department of Cell Toxicology and Professor at the University of Tübingen. “It is known from environmental and water studies that the effects of chemicals add up when they occur in low concentrations in complex mixtures. Whether this is also the case in the human body has not yet been sufficiently investigated – this is precisely where our study comes in.” 

The extensive research work was based on over 600 blood samples from pregnant women from the Leipzig mother-child cohort LiNA, which has been coordinated by the UFZ since 2006. The researchers first analysed the individual mixtures of chemicals present in these samples.

“We wanted to find out which chemicals were contained in the blood plasma and in what concentrations. We used a two-step extraction process to isolate as diverse chemical mixtures as possible,” says Georg Braun, postdoctoral researcher in Beate Escher’s working group and first author of the study. “Using mass spectrometry analyses, we searched for 1000 different chemicals that we knew could occur in the environment, could potentially be ingested by humans and could be relevant for adverse human health effects. Of these, we were able to quantify around 300 chemicals in several plasma samples.” This provided the researchers with information on the composition and concentration ratios of the chemical mixtures present in the 600 individual plasma samples. 

The researchers used a prediction model to calculate the neurotoxic effects of the chemical mixtures. To test the predictions of the mixture effects experimentally, they used an established cellular bioassay based on human cells that indicates neurotoxic effects.

“We analysed individual chemicals as well as around 80 different, self-produced chemical mixtures in realistic concentration ratios. The extracts of the plasma samples were also tested,” says Georg Braun. The results were clear. “The laboratory experiments confirmed the predictions from the model: the effects of the chemicals add up in complex mixtures,” says environmental toxicologist Beate Escher. “Even if the individual concentrations of neurotoxic chemicals are so low that they are each below the effect threshold, there is still an effect on nerve-like cells in complex mixtures with many other chemicals.”

But what exactly do these results mean? “With our study, we were able to prove for the first time that what is known about the effects of chemical mixtures in the environment also applies to humans,” says Escher. “It is therefore imperative that we rethink risk assessment. Indicator substances alone are far from sufficient. In future, we must learn to think in terms of mixtures.” UFZ environmental immunologist and head of the LiNA study Dr Gunda Herberth adds: “It is becoming increasingly clear that many diseases such as allergies, immune system disorders, obesity or the development of the nervous system are linked to exposure to chemicals in the womb or in early childhood.” 

The test method presented in this study – the extraction of chemical mixtures from human samples and their characterisation using chemical analysis combined with cell-based biotest systems – opens up new possibilities for researching the effects of complex chemical mixtures on human health. In future research projects, the scientists want to refine their test method and investigate the effects of chemical mixtures on other health-relevant endpoints such as immunotoxicity. In addition, they would like to uncover possible links between chemical exposure and the development of developmental disorders in children. 

Source: Helmholtz Centre for Environmental Research – UFZ

Categories : Endocrinology Environmental EffectsTags :

Airborne Levels of Chemicals Released by Plastics Shock Researchers

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A new study documents how people in California are chronically being exposed to toxic airborne chemicals called plasticisers, including one banned from children’s items and beauty products. 

Plasticizers are chemical compounds that make materials more flexible. They are used in a wide variety of products ranging from lunchboxes and shower curtains to garden hoses and upholstery. 

“It’s not just for drinking straws and grocery bags,” said David Volz, environmental sciences professor at UC Riverside, and corresponding author of the study published in the journal Environmental Research. 

Previous California monitoring programs focused on plasticisers called ortho-phthalates, some of which were phased out of manufacturing processes due to health and environmental concerns. Less research has focused on the health effects of their replacements, called non-ortho-phthalates. This study revealed the presence of both types of plasticisers in the air throughout Southern California.

“The levels of these compounds are through the roof,” Volz said. “We weren’t expecting that. As a result, we felt it was important for people to learn about this study.”

The National Institute of Environmental Health Sciences also wants to increase the visibility of this study, one of only a few to document the phthalates’ presence in the air of urban environments. The institute’s monthly newsletter, Environmental Factor, highlights the study in their October 2024 issue.  

The researchers tracked two groups of UCR undergraduate students commuting from different parts of Southern California. Both groups wore silicone wristbands designed to collect data on chemical exposures in the air. 

The first group wore their wristbands for five days in 2019, and the second group wore two different wristbands for five days each in 2020. Both groups wore the bands continuously, all day, as they went about their activities. At the end of the data collection period, the researchers chopped the wristbands into pieces, then analysed the chemicals they contained. 

In a previous paper, the team focused on TDCIPP, a flame-retardant and known carcinogen, picked up in the wristbands. They saw that the longer a student’s commute, the higher their exposure to TDCIPP. 

Unlike TDCIPP, which most likely migrates out of commuters’ car seats into dust, the team cannot pinpoint the origin of the plasticisers. Because they are airborne, rather than bound to dust, the wristbands could have picked them up anywhere, even outside the students’ cars.

For every gram of chopped-up wristband, the team found between 100 000 and 1 million nanograms of three phthalates, DiNP, DEHP, and DEHT. Ten total plasticizers were measured, but the levels of these three stood out.

Both DiNP and DEHP are included on California’s Proposition 65 list, which contains chemicals known to cause cancer, birth defects, or other reproductive harm. DEHT was introduced as an alternative, but its effects on human health have not been well studied. 

This study suggests that introducing DEHT also has not done much to reduce the public’s level of exposure to DiNP or DEHP. Levels of all three chemicals found by Volz and his team were similar to those found by researchers in unrelated studies conducted on the East Coast. 

Despite differences in climate, the air on both coasts is likely carrying similar levels of phthalates.

“No matter who you are, or where you are, your daily level of exposure to these plasticizer chemicals is high and persistent,” Volz said. “They are ubiquitous.”

To Volz, studies like this one amplify the need to find alternatives to plastic. As plastics degrade, these compounds and others like them are leaching out into the environment and into the body. 

“The only way to decrease the concentration of plasticisers in the air is to decrease our production and consumption of materials containing plasticisers,” he said. 

Source: University of California – Riverside

Categories : Environmental Effects PaediatricsTags :

Girls may Start Puberty Early Due to Chemical Exposure

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Girls exposed to certain endocrine-disrupting chemicals (EDCs) may be more likely to start puberty early, according to new research published in Endocrinology, the flagship basic science journal of the Endocrine Society. EDCs mimic, block or interfere with hormones in the body’s endocrine system.

There has been an alarming trend toward early puberty in girls, suggesting the influence of chemicals in our environment. Early puberty is associated with an increased risk of psychosocial problems, obesity, diabetes, cardiovascular disease, and breast cancer.

“We conducted a comprehensive screen of 10 000 environmental compounds with extensive follow-up studies using human brain cells that control the reproductive axis, and our team identified several substances that may contribute to early puberty in girls,” said study author Natalie Shaw, MD, MMSc, of the National Institute of Environmental Health Sciences (NIEHS).

Those substances include musk ambrette, which is a fragrance used in some detergents, perfumes, and personal care products, and a group of medications called cholinergic agonists.

“More research is needed to confirm our findings,” noted Shaw. “But the ability of these compounds to stimulate key receptors in the hypothalamus – the gonadotropin-releasing hormone receptor [GnRHR] and the kisspeptin receptor [KISS1R] – raises the possibility that exposure may prematurely activate the reproductive axis in children.”

According to the research team, musk ambrette is potentially concerning because it can be found in personal care products, and some rat studies have suggested it can cross the blood-brain barrier. Children are less likely to encounter cholinergic agonists in their daily lives.

Canadian and European regulations restrict musk ambrette use because of its potential toxicity, and the U.S. Food and Drug Administration removed the fragrance from its “generally recognized as safe” list. Yet it is still available on the market in some personal care products.

“This study suggests that, out of an abundance of caution, it is important for parents to only use personal care products for their children that are federally regulated,” Shaw said.

As part of the study, the research team screened a Tox21 10 000-compound library of licensed pharmaceuticals, environmental chemicals and dietary supplements against a human cell line overexpressing GnRHR or KISS1R. They conducted follow-up analysis using human hypothalamic neurons and zebrafish, finding that musk ambrette increased the number of GnRH neurons and GnRH expression.

“Using human hypothalamic neurons and zebrafish provides an effective model for identifying environmental substances that stimulate the KISS1R and GnRHR,” said co-author Menghang Xia, PhD, from the National Center for Advancing Translational Sciences (NCATS) “This study was a multidisciplinary team effort, and it showed that we can efficiently reduce the time and cost of assessing environmental chemicals for their potential effects on human health.”

Source: Endocrine Society

Categories : Environmental Effects GenderTags :

Older Women more Vulnerable to Heat than Men, Researchers Find

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As global climate change causes extreme heat waves to become more common around the world, epidemiological studies have shown that heat kills more women than men. Now, a new study by researchers at Penn State has found that older women are physiologically more vulnerable to high heat and humidity than older men, and that women between the ages of 40 and 64 are as vulnerable as men 65 years of age or older. This is the first study to determine this disparity exists due to physiological differences rather than from a preponderance of women at old age due to greater longevity.

Led by Olivia Leach, doctoral candidate in kinesiology at Penn State, and her adviser, W. Larry Kenney, professor of physiology and kinesiology at Penn State, the researchers demonstrated that middle-aged and older women were affected by heat at lower temperature/humidity combinations than middle-aged and older men. The results, published in the American Journal of Physiology-Regulatory, Integrative and Comparative Physiology, were somewhat unexpected, according to Leach, because there are no differences in heat vulnerability based on biological sex in adults younger than 30.

While the researchers did not directly compare middle-aged men to middle-aged women, the physiological responses of middle-aged women were similar to the responses of older men in the study, which demonstrated that middle-aged women are more vulnerable to heat than men of the same age.

“In addition to demonstrating that middle-aged and older women are at greater risk from extreme heat, we also identified what levels of heat and humidity are safe for women as they age,” Leach said. “This information is presented as a temperature/humidity curve based on a person’s age, and it can be useful for setting policies designed to keep people safe during a heat wave.”

The researchers tested the heat thresholds of 72 participants between 40 and 92 years of age in a specialized environmental chamber in Kenney’s laboratory. Before the experiment, participants swallowed a tiny device encased in a capsule that measured their core temperature throughout the experiment.

During the study, participants entered the specialised environmental chamber where they performed light physical activity to simulate the effort of minimal day-to-day tasks – the types of things people would need to do even during a heat wave. The researchers then gradually increased the temperature and/or humidity in the chamber until the participant’s body could no longer adequately cool itself, and their core temperature began to rise.

The study is part of the PSU HEAT, or Human Environmental Age Thresholds, project, led by Kenney. For five years, researchers in the PSU HEAT project have examined the levels of combined heat and humidity that humans can tolerate before their core temperatures begin to rise. When core temperatures rise, people become vulnerable to heat-related illnesses including heat exhaustion, heat stroke and even death.

“We’re not saying that people who experience a certain temperature will necessarily become sick or die,” Kenney said. “We are identifying the limits of livability – the thresholds where people can no longer continue their daily life unimpeded. Once people reach these temperatures, they need to take actions like seeking air conditioning to cool their bodies.”

Previous research by Kenney and others demonstrated that people become increasingly vulnerable to heat as they age, because their ability to efficiently sweat and pump blood to the skin – two primary cooling mechanisms – decreases. Sweat evaporation carries heat away from the body, while extra blood pumped to the skin dissipates heat to the environment and supports sweating.

To date, the PSU HEAT project has conducted more than 600 experiments on nearly 200 participants between ages 18 and 92, but the results of this experiment still yielded surprises, according to Leach.

“Among young adults, there is no difference in heat vulnerability between men and women,” Leach said. “Young people tend to be healthier, so any measurable health metric – from blood pressure to cholesterol – is more homogeneous among young people than it is among older people.”

As with other health measures, older adults have a wide range in their vulnerability to heat, Leach explained.

“We have examined many factors that might explain who faces the most risk in a heat wave,” Leach said. “We found that age and biological sex are the two most important factors that can predict whether a healthy adult would be at risk from high heat and humidity.”

While cardiovascular health and certain medications can affect a person’s sensitivity to heat, biological sex and age appear to be the two primary drivers of heat vulnerability among healthy people, the researchers said.

“Other factors – for example someone’s cardiovascular fitness or their body mass – have little impact on how vulnerable a person is to heat at rest or during light activity,” Leach continued. “Older women really are at greater risk from heat than other people. As governments and other social leaders prepare for extreme heat to become more common, the vulnerability of older women needs to factor into their planning.”

Source: Penn State

Categories : Cardiovascular Disease Environmental EffectsTags :

Exposure to Chronic Occupational Noise Drives up Blood Pressure

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Noise exposure is a known occupational hazard in some jobs, particularly for hearing loss, physical and psychological stress, and reduced concentration. A new study presented at the ACC Asia 2024 conference found in adult power loom weavers, chronic noise exposure not only increased their blood pressure overall, but also each year of exposure increased their odds of having high blood pressure by 10%.

“While the mechanism is still not well-explored, it is thought that the stress response by the body to chronic sound exposure causes hormonal imbalances that gradually leads to a permanent elevation of blood pressure,” said Golam Dastageer Prince, MBBS, MPH, medical officer at DGHS Bangladesh and the study’s lead author. “High blood pressure impacts more than a billion people worldwide and just 1 in 5 have it under control, yet it is a major cause of premature death. In addition to treating the high blood pressure through appropriate means, we must find ways to mitigate the exposure to the noise if we want to reduce the cardiovascular risk of these patients.”

Researchers at the Directorate of General Health Services in Bangladesh looked at 289 adult workers in selected weaving factories in the Araihazar sub-district of Narayanganj, Bangladesh, from January to December 2023. Participants took a face-to-face interview to complete a questionnaire covering sociodemographic variables, behaviour, dietary habits and family medical history. Blood pressure, height, weight and noise intensity were measured following standard procedures by the researchers.

The study cohort was predominantly male and married and were about 34 years of age on average. According to the researchers, a notable proportion of the cohort was illiterate. Workplace exposure duration averaged nearly 16 years, with noise intensity ranging from 96–111 decibels. In the United States the National Institute for Occupational Safety and Health has established the recommended exposure limits for occupational noise exposures to be 85 decibels on average over an eight-hour workday. Sounds at or below 70 decibels are generally considered safe.

According to Prince, none of the study population was found to be wearing ear protection personal protective equipment.

“Hopefully we can raise awareness of not only noise-induced hearing loss, but the impact of noise on blood pressure and workers’ behaviors and attitudes towards using personal protective equipment,” Prince said. “Pushing for structural improvements to industries may also help us improve the health safety of these workers.”

The study population had a 31.5% rate of high blood pressure with an additional 53.3% being prehypertensive. The study also found a positive correlation between blood pressure and noise exposure duration. Each year of exposure was found to increase high blood pressure odds by 10%, even after adjusting for age, body mass index and smoking status.

“As the study focused on workers exposed to more than 85 decibels noise for long periods of time, any profession causing workers to experience similar exposure might experience similar blood pressure impacts,” Prince said. “We definitely need more exploratory studies to reveal more information about the potential mechanisms and long-term health outcomes.”

Recent studies have shown that living near noise pollution, including highways, trains and air traffic, can have an impact on cardiovascular health. However, the current study may not apply to noise experienced during daily life. Noise pollution experienced near home typically ebbs and flows, while the industrial exposures in the study are typically continuous in pattern due to the machinery and remain at a constant sound level, according to Prince.

Source: American College of Cardiology

Categories : Cardiovascular Disease Environmental EffectsTags :

Benefits of UV Exposure may Outweigh Risks in Low-sunlight Countries

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The health benefits of spending time in the sun could outweigh the risks for those living in areas with limited sunshine, a UK study suggests. In low-sunlight locations such as parts of the UK, exposure to higher levels of ultraviolet (UV) radiation was linked to a drop in deaths due to cardiovascular disease and cancer.

Adapting public health advice to reflect both the risks and benefits of UV exposure may help to reduce disease burden and improve life expectancy in low-sunlight countries, the research team says.

Experts caution that measures should still be taken to protect the skin when UV levels are high, to prevent sunburn and the development of skin cancer.

Volunteer data

University of Edinburgh scientists used genetic and health information from the UK BioBank – an anonymised database of health details from volunteers – to examine the UV exposure of 395 000 people across the UK. Participants were restricted to those of white European descent, due to the role skin pigmentation plays in the body’s response to UV exposure.

The team applied two measures to identify those exposed to higher levels of UV. They used the geographical location of participants to calculate their average annual exposure to solar energy and, separately, whether they used sunbeds.

The findings were adjusted for other factors that might influence health – including smoking, exercise, social deprivation and gender – to reduce the chance that these factors were responsible for any of the changes observed.

Health impact

Living in locations with higher UV levels, for example Cornwall, was associated with a lower risk of death from cardiovascular disease and cancer – 19% and 12%, respectively – than living in areas with lower UV levels, such as Edinburgh or Glasgow.

Sunbed use was linked to a 23% lower risk of death from cardiovascular disease and a 14% lower risk of death from cancer, compared to non-users. It is possible that people who use sunbeds may also seek out greater sun exposure and so this result may reflect broader sun seeking behaviour, the team says.

Those with a higher estimated UV exposure had a slightly increased risk of being diagnosed with melanoma, but their risk of dying from the condition was not raised.

As the study is based on UK data from a white European population, the findings are of most relevance to similar groups in low-sunlight countries. Further research into locations with higher UV exposure is needed to build a clearer picture of the potential benefits to health, experts say.

The study, funded by Health Data Research UK, is published in the journal Health and Place.

Our paper adds to a growing body of evidence suggesting that in lower light environments, relatively higher exposure to UV is good for your health. Though there may be an increased risk of skin cancer incidence with higher UV exposure, this risk appears to be outweighed by a larger reduction in the risk of death from cancer and cardiovascular related disease.

Professor Chris Dibben, University of Edinburgh’s School of GeoSciences

Dermatologists have traditionally only considered possible harm to the skin caused by sunlight, much of which dates from the experience of white-skinned individuals in sunny countries such as Australia. When the UV index is very high, protecting skin is important.

However, this research shows that in the UK, the balance of benefit and risk from sunlight exposure is probably very different from that in sunnier countries.

Professor Richard Weller, University of Edinburgh’s Centre for Inflammation Research

Source: The University of Edinburgh