Long term exposure to arsenic in water may increase cardiovascular disease and especially heart disease risk even at exposure levels below the federal regulatory limit (10µg/L) according to a new study at Columbia University Mailman School of Public Health. 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 ischemic heart disease.
The researchers 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. The findings are published in the journal Environmental Health Perspectives.
“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 U.S. 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, 6,119 ischemic heart disease cases and 9,936 CVD cases. Excluded were those 85 years of age or older and those with a history of cardiovascular disease at enrollment. Similar to the proportion of California’s population that relies on CWS (over 90 percent), most participants resided in areas served by a CWS (92 percent). 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 percent) 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 ischemic heart disease, with increases of 5 to 6 percent. Risk jumped to 20 percent 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 percent 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 percent risk at arsenic exposures ranging from 5 to <10 µg/L which affected about 3.2 percent 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 neighborhoods.
“Our results are novel and encourage a renewed discussion of current policy and regulatory standards,” said Columbia Mailman’s 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.”
Co-authors are Komal Bangia, Office of Environmental Health Hazard Assessment, Oakland, California; James V. Lacey Jr and Emma S. Spielfogel, California Teacher Study, Beckman Research Institute, City of Hope, Duarte, California; and Jared A Fisher, Jessica M. Madrigal, Rena R. Jones, and Mary H. Ward, Division of Cancer Epidemiology and Genetics, National Cancer Institute.
The study was supported by the National Cancer Institute, grants U01-CA199277, P30-CA033572, P30-CA023100, UM1-CA164917, and R01-CA077398; and also funded by the Superfund Hazardous Substance Research and Training Program P42ES033719; NIH National Institute of Environmental Health Sciences P30 Center for Environmental Health and Justice P30ES9089, NIH Kirschstein National Research Service Award Institutional Research Training grant T32ES007322, NIH Predoctoral Individual Fellowship F31ES035306, and the Intramural Research Program of the NCI Z-CP010125-28.
Columbia University Mailman School of Public Health
Founded in 1922, the Columbia University Mailman School of Public Health pursues an agenda of research, education, and service to address the critical and complex public health issues affecting New Yorkers, the nation and the world. The Columbia Mailman School is the third largest recipient of NIH grants among schools of public health. Its nearly 300 multi-disciplinary faculty members work in more than 100 countries around the world, addressing such issues as preventing infectious and chronic diseases, environmental health, maternal and child health, health policy, climate change and health, and public health preparedness. It is a leader in public health education with more than 1,300 graduate students from 55 nations pursuing a variety of master’s and doctoral degree programs. The Columbia Mailman School is also home to numerous world-renowned research centers, including ICAP and the Center for Infection and Immunity. For more information, please visit www.mailman.columbia.edu.
Journal
Environmental Health Perspectives
Article Title
Long-term exposure to arsenic in community water supplies and risk of cardiovascular disease among women in the California Teachers Study
TOXIC MASCULINITY
Cardiovascular disease remains a top cause of sickness and death in the U.S. and worldwide. Doctors and researchers have it especially high on their radar because it’s more modifiable and preventable than many other diseases and causes of death.
Importantly, though, modification and prevention rely on early detection and mitigation of risk factors like hypertension and high cholesterol. Unfortunately, detection and mitigation are suboptimal throughout the U.S. population: Experts estimate that up to 75% of young adults who have risk factors such as hypertension and high cholesterol are unaware of their conditions.
A recent study led by researchers at the University of Chicago found that boys and men who enact behaviors more closely aligned with stereotypical gender norms in their social environment are less likely to report receiving diagnoses or treatment for cardiovascular disease risk factors. Their findings build on existing research showing that sociocultural pressures to perform male gender identity are linked to detrimental health-related behaviors, such as substance use and rejection of medical therapies and recommendations.
“It’s well known that male gender and male sex are associated with lower help-seeking for a range of health conditions — especially mental health and primary care. But previous studies haven’t probed further into the social processes through which male gender is iteratively created through an interplay between the individual and their surroundings,” said Nathaniel Glasser, MD, a general internist and pediatrician at UChicago Medicine and lead author on the paper. “In this new paper, we used innovative measurement techniques to look at the construction of male gender and how it's associated with cardiovascular disease prevention.”
Glasser and his colleagues analyzed data from Add Health, a nationally representative, longitudinal study that collected health measurements and survey responses from more than 12,300 people at multiple points over the course of 24 years (1994-2018). They quantified Add Health participants’ male gender expressivity by identifying a subset of survey questions that were answered most differently by self-identified male versus female participants, then measuring how closely male participants’ answers to those questions matched those of their same-gendered peers.
“When we talk about gender expression, we’re not looking at anything physiologic that could be affected by the Y chromosome,” Glasser pointed out. “We’re purely focused on self-reported behaviors, preferences and beliefs, and how closely these reported behaviors and attitudes resemble those of same-gendered peers.”
Zeroing in on cardiovascular disease, the researchers compared the Add Health biological measurements with health-related survey responses to see if men with detectable risk factors like high blood pressure reported receiving diagnoses or treatment for those conditions. They found that men who showed more stereotypical gender expression were significantly less likely to report that a healthcare professional had ever told them about certain cardiovascular disease risk conditions. Even when these men did report having previously received a diagnosis, they were still less likely to report that they were taking medication to treat these conditions.
The risk factors examined in the study are all conditions that would normally be detected by screenings that are part of basic primary care. It’s unclear whether the decrease in reported diagnosis and treatment among those with higher male gender expression indicates that men aren’t going in to get screened; that they aren’t paying attention to their diagnoses even when they do get screened; or that they are simply downplaying their diagnoses when asked about them. Whatever the underlying reason, the findings highlight a missed opportunity to prevent or alleviate serious cardiovascular conditions later in life.
“Our hypothesis is that social pressures are leading to behavioral differences that impact cardiovascular risk mitigation efforts, which is concerning because it could be leading to worse long-term health outcomes,” Glasser said.
Ultimately, the authors see the implications of this research reaching far beyond the topic of traditional masculinity.
“We’re seeing how pressures to convey identity — whether it’s rooted in gender, race, sexuality or something else — impact health behaviors,” Glasser said. “Fitting in and achieving belonging is a complicated task, and we feel strongly that increased societal sympathy, empathy and patience for others undertaking that task would be good for people’s health.”
“Male Gender Expressivity and Diagnosis and Treatment of Cardiovascular Disease Risks in Men” was published in JAMA Network Open in October 2024. Authors include Nathaniel Glasser, Jacob Jameson, Elbert Huang, Ian Kronish, Stacy Tessler Lindau, Monica Peek, Elizabeth Tung and Harold Pollack.
Method of Research
Data/statistical analysis
Subject of Research
People
Article Title
Male Gender Expressivity and Diagnosis and Treatment of Cardiovascular Disease Risks in Men
Article Publication Date
25-Oct-2024
