According to the U.S. Centers for Disease Control and Prevention (CDC) nearly 535,000 children between 1 and 5 years of age, have blood lead levels high enough to damage their health; 24 million homes contain lead-based paint and elevated levels of contaminated house dust. Costs to the community for lead poisoning in children include up to $53 billion in additional health care costs, tax revenue losses up to $35 billion, special education costs up to $146 million and the direct cost of crime, estimated at $1.7 billion.
According to the CDC, there is no known identified safe blood lead level for children or adults. Children exposed to lead have an increased risk of damage to their nervous system, brain and cognitive development, slowed growth and development and hearing and speech problems.
Although lead is a well-recognized neurotoxin, the U.S. has not paid close attention to exposure over the years. In fact, in 1923 the country introduced leaded gasoline, which triggered near unfathomable repercussions for the global community. Recent research published in the Lancet Public Health Journal found lead levels in adults are strongly correlated with a higher risk of death from cardiovascular complications.
Study Demonstrates Lead Is a Serious Threat to Children and Adults
Researchers gathered 20 years of data using a nationally representative sample of over 14,000 adults enrolled in the National Health and Nutrition Examination Survey between 1988 and 1994. Each of the participants underwent medical testing, including quantifying lead levels in their blood. After analyzing the data, researchers discovered a link between low-level exposure to lead and increased risk of premature death.
In the past, lead exposure had been associated with high blood pressure, coronary artery disease and atherosclerosis. Researchers point out historical exposure to lead is based on past use of lead-based gasoline, paint and plumbing. Ongoing exposure from food, industrial emissions and water toxicity may also affect blood lead levels in younger children. Lead author of the study, Dr. Bruce Lanphear, professor at Simon Fraser University in Canada, commented:
“Our study estimates the impact of historical lead exposure on adults currently aged 44 years old or over in the USA, whose exposure to lead occurred in the years before the study began … Today, lead exposure is much lower because of regulations banning the use of lead in petrol, paints and other consumer products so the number of deaths from lead exposure will be lower in younger generations.”
Although scientists have known the toxic effects of lead exposure for centuries, the number of people affected by the cardiovascular effects were surprising, even to the researchers. In the initial 14,000 respondents, 4,400 had died by 2011. From this the researchers calculated approximately 18 percent of deaths could have been prevented by reducing blood lead concentrations to 1.0 micrograms per deciliter.
The researchers extrapolated from the data more than 400,000 deaths in the U.S. every year could be linked lead exposure from all sources. Nearly 250,000 of those are the result of cardiovascular disease and 185,000 are related to coronary artery disease. These numbers are nearly 10 times greater than the current estimates of deaths related to lead in adults. Lanphear goes on to say:
“Nobody had even tried to estimate the number of deaths caused by lead exposure using a nationally representative sample of adults. But if we’re underestimating the impact of lead exposure on cardiovascular disease mortality and other important outcomes beyond IQ, then it might have a big impact on the way we make investments in preventing lead poisoning exposure …
When you start looking at the risk across the entire range of people exposed, all of a sudden the number of affected people balloons. Mostly it’s a numbers thing — there are so many people in the low- to moderate-risk groups that, as long as there are some risks with low-level exposure, many more people are going to die or develop heart disease.”
Brain Cells and Blood Vessels
The scientists included deaths from multiple causes and not just those from heart disease. They found higher blood lead levels were tied to more than 410,000 deaths in the U.S. annually, which was 10 times more than was previously estimated and close to the 480,000 smokers who die every year. While smoking, lack of exercise and an unhealthy diet are contributors to cardiovascular disease, environmental factors may also have an impact on increasing your risk of heart problems.
Although the most recent study has identified an unexpected number of people affected by lead poisoning and cardiovascular changes, previous research has demonstrated the effect lead has on endothelial cells and in crossing the blood-brain barrier. The cellular effect of lead in the brain occurs as it disrupts the blood-brain barrier and triggers encephalopathy and edema, primarily in the cerebellum.
Infants are at greatest risk for developing cognitive impairments, but adults are also at risk of lead intoxication with higher blood lead levels. Lead-induced hypertension and cardiovascular disease is the result of several disruptions to the endothelial system. Chronic lead exposure promotes oxidative stress and limits nitric oxide availability, which in turn reduces flexibility of the endothelial wall.
Each of the following factors raises the risk for hypertension, endothelial dysfunction, arteriosclerosis and cardiovascular disease. As these changes also occur in the endothelium within the brain, they may possibly have an impact on cognition and risks for dementia in the elderly. Other research has demonstrated that lead:
|Generates superoxide and hydrogen peroxide, which in turn reacts with nitric oxide and produces peroxynitrites||Stimulates vascular smooth muscle cell proliferation and phenotypic transformation|
|Disturbs vascular smooth muscle calcium signaling||Modifies vascular response to vasoactive antagonists|
|Raises plasminogen activator inhibitor-1 production||Suppresses proteoglycan production|
|Causes endothelial injury||Impedes endothelial repair|
|Inhibits angiogenesis||Promotes inflammation|
Your Water Supply May Increase Your Risk of Contamination to Multiple Poisons
In a study gathering data from over 30 years, researchers found nearly 8 percent of Americans were drinking water that violates health standards. The study was the first to assess nationwide violations in drinking water quality, looking at violations in 17,900 community water systems. In any given year from 1982 to 2015, when data was collected, between 9 and 45 million people were affected.
More than 600,000 observations were made over the life of the study and were more likely to occur in low-income areas using public-owned water systems. Under the Safe Drinking Water Act of 1974 the Environmental Protection Agency (EPA) regulates water quality, but each state has different reporting mandates. Erik Olson, health program director at Natural Resources Defense Council, which analyzed the EPA’s data for its report, characterized the effect of the report:
“Imagine a cop sitting, watching people run stop signs, and speed at 90 miles per hour in small communities and still doing absolutely nothing about it — knowing the people who are violating the law. And doing nothing. That’s unfortunately what we have now.”
According to the report, more than 5,300 water systems are in violation of lead and copper rules, yet states took action on only 817 cases and the EPA took action in just 88 cases. Even worse, the report revealed the EPA was aware many municipalities used loopholes to avoid detecting high lead levels, which means many more communities may be exposing their residents to potentially dangerous levels of lead.
Following an effort to save money, in August 2015, Virginia Tech scientists discovered Flint, Michigan’s, tap water was contaminated with lead at dangerously high levels. One woman reported her water tested 104 parts per billion (ppb) of lead, nearly seven times greater than the EPA’s limit of 15 ppb.
Between 2014 and 2015, 87 people in Genesee County, Michigan, where Flint is located, contracted Legionnaires’ and 10 died. It was considered one of the worst outbreaks of Legionnaires’ in U.S. history. According to the county health director Jim Henry, state officials had blocked the CDC from investigating the outbreak.
Henry suspected Flint River water right from the start, but CDC protocols require an invitation from state officials. County officials requested help from the CDC, but they never showed up because state officials never issued the prerequisite invitation. Such extreme problems with water quality are not exclusive to Flint, as the EPA has not made their water testing and treatment standards into enforceable regulations.
This has left cities and states to police themselves. Yanna Lambrinidou, assistant professor in the science and technology studies department at Virginia Polytechnic Institute and State University, who advised the EPA on changes to federal water standards, commented on the possibility of another emergency, such as Flint, Michigan: “Do I expect more Flints to happen? I think it’s very, very possible. I worry tremendously about water in other cities.”
Leaded Gasoline Poisoned the Public
In this short video you’ll discover the history of how lead came to be added to gasoline, despite being one of the best known poisons from as early as 2,000 years ago until occupational poisonings occurred during the industrial revolution. For nearly 80 years, lead was used in gasoline, polluting the air children and adults breathed.
Although other less toxic solutions to an engine knock problem were available, lead was chosen as an additive to gasoline since it was the most profitable, and allowed the oil industry to control both the product and their profits. The push to remove lead from gasoline began with the work of the late Clair Patterson, Ph.D, a former geochemist for the California Institute of Technology.
He worked on the Manhattan Project, but is best known for his pioneering work in 1963 to establish the age of the Earth as 4.5 billion years old. He accomplished this by analyzing certain isotopes of lead. However, he struggled with conflicting results in his research until he realized the problem was caused by environmental lead pollution. It wasn’t until he analyzed an ancient pristine ice core sample taken from Greenland that he found the source of the problem.
He was able to determine ice layers corresponding to specific eras in time, such as the Roman era, the Industrial Revolution and the advent of leaded gasoline in the mid-1920s. In the core sample beginning in the 1920s he noted a major spike in lead concentrations. He was the first who fully appreciated lead gasoline had polluted every last corner of the globe. As a result, people worldwide were exposed to lead pollution with very serious health consequences.
Despite massive efforts to discredit him, Patterson pursued the elimination of lead from gasoline. The first hurdle was cleared in 1975 when the U.S. mandated the use of unleaded gasoline to protect catalytic converters. However, it was another 11 years before his persistence caused the complete removal of lead from all gasoline in the U.S As a result, blood lead levels in Americans dropped by nearly 80 percent by the late 1990s.
Strategies to Avoid Lead Exposure
Lead in the blood is typically measured using micrograms per deciliter (mcg/dL) or ppb. In the past, the CDC used levels of 40 mcg/dL as acceptable concentrations. This was reduced to 10 mcg/dL in the early 1990s, and then 5 mcg/dL in the mid 2010s. However, despite creating thresholds, the CDC cautions no safe level of lead has ever been identified. Lanphear commented on the necessity to remove lead contamination completely, saying:
“Our study calls into question the assumption that specific toxicants, like lead, have ‘safe levels.’ [Rather it] suggests that low-level environmental lead exposure is a leading risk factor for premature death in the USA, particularly from cardiovascular disease.”
The issue of preventing lead poisoning is a pressing matter, whether you have young children in your home or not. Adults are also adversely affected by lead contamination, including neurological dysfunction and cardiovascular damage. Harvard Medical School offers the following suggestions to protect yourself and your family against lead exposure:
- Was your home built before 1978? If so, get it inspected to determine whether it has any lead paint
- Lead paint removal should be done by a certified professional to ensure safety. The dust is highly toxic. For more information on this, see the EPA’s “Lead-Based Paint Activities Professionals” page
- Get your water tested for lead
- Be mindful of the fact certain household objects may also contain lead. For information about lead-containing products and recalls, see the Consumer Products Safety Commission’s website
- Get your child and yourself tested for lead. Ideally, all children should be tested at ages 1 and 2, and again at ages 3 and 4 if you live in an older home. It’s also recommended to test your child’s level whenever there’s concern about exposure. A level of 5 mcg/dL or higher is considered dangerous