Friday, December 24, 2010
'Twas the Night Before Christmas
Wednesday, May 26, 2010
Call to Action
The ultimate outcome of this research will be information that can be used to guide policy by identify chemicals of concern, determine exposure levels that lead to health effects, and evaluate the effectiveness of prevention efforts. But beyond policy, this data will allow people to make better choices, such as where to live or types of health care they need.
Investment in environmental health research clearly has the potential to improve Americans quality of life and reduce economic and societal costs that result from environmentally-related health effects. As voters, we have the power to encourage investment in this research by telling the representatives we elected that it is how we want our tax dollars spent. The greatest impact you can have is by communicating with your representatives.
I am writing letters to my Senators and Representatives on how I believe environmental health research should be a priority, will you join me?
This is Part 10 in the Chemical Exposures and Public Health series.
Part 1 - From Interest to Passion
Part 2 - An Environmental Health Risk
Part 3 - Lead: A Regulatory Success Story
Part 4 - Something My Body Needs Anyway?
Part 5 - Obesity's Elephant: Environmental Chemicals
Part 6 - Why Our Approach to Toxicology Must Change
Part 7 - Failures of U.S. Chemical Regulation
Part 8 - Cleaning Up Our Act
Part 9 - Environmental Health Research Saves Lives and Money
Part 10 - Call to Action
Monday, May 24, 2010
Environmental Health Research Saves Lives and Money

The same research tools can also be used to guide chemical regulatory policy. To encourage regulation of a specific chemical, research needs to prove it poses a threat to human health. To better understand the risk posed by chemical exposures, scientists first needed to develop methods to identify which chemicals are getting into our bodies and at what levels. One technique is bio-monitoring; which involves looking at both the environment a person lives in and samples from the person themselves.
Historically, human exposures were estimated from the concentration of a chemical in the environment, food, water, or consumer goods. But advances have enabled scientists to directly measure the concentration of a chemical or metabolites in specimen, such as blood, urine, or bone. A recent CDC study detected over 212 chemicals in the U.S. population. Even DDT was found at a detectable level in children, despite the fact that it had been banned decades before they were born.
But what does bio-monitoring data mean for public health? The problem is that bio-monitoring studies on their own do not determine the relationship between chemical exposures and health effects. Bio-monitoring is the first step, but can only determine what enters our bodies. In order for regulatory action to be taken, these chemical exposures must be linked to specific effects, as was done for children's lead exposure and mental deficits. Unfortunately, for endocrine disrupting chemicals (EDCs) many links remain unknown.
To better determine links between environmental exposures and health effects, a multi-agency collaboration is conducting a national research effort called the National Children’s Study . The study will track 100,000 children from before birth to the age of 21 collecting data on their chemical exposures and potentially related health effects. Then, researchers will analyze the data to learn how environment influences health, including evidence identifying which chemicals in our bodies are making us sick.
The study is focusing on children because research has documented their unique vulnerability to chemicals, and how exposures during development can set us up for chronic health problems and the development of diseases later in life.
Because of the sheer size and length, the National Children’s Study will be expensive. To get the full benefit, it is critical that funding is maintained. This study is about prevention, we need to try to stop environmentally related health effects before they start. Investment in environmental health research is important because of the clear potential to save both lives and treatment costs.
This is Part 9 in the Chemical Exposures and Public Health series.
Part 1 - From Interest to Passion
Part 2 - An Environmental Health Risk
Part 3 - Lead: A Regulatory Success Story
Part 4 - Something My Body Needs Anyway?
Part 5 - Obesity's Elephant: Environmental Chemicals
Part 6 - Why Our Approach to Toxicology Must Change
Part 7 - Failures of U.S. Chemical Regulation
Part 8 - Cleaning Up Our Act
Part 9 - Environmental Health Research Saves Lives and Money
Part 10 - Call to Action
Thursday, May 20, 2010
Cleaning Up Our Act
In my last post, I described some of the legislative hurdles for U.S. chemical regulation. How can Americans encourage positive change? The best ways to influence policy is through public support since legislators respond to their constituents concerns. Advocacy is an effective tool to raise public awareness and is most powerful when backed by research.
A
However, a specific chemical being removed does not guarantee the new product is any safer. Manufactures simply swap one chemical for another, but just like the initial chemical, the alternatives are not being thoroughly tested for safety. It becomes a game of 'whac-a-mole', with
What's the best way to ensure that the environmental chemicals we are exposed to are safe? Research. Stay tuned for the next part of this series on the benefits of Environmental Health Research.
This is Part 8
Part 1 - From Interest to Passion
Part 2 - An Environmental Health Risk
Part 3 - Lead: A Regulatory Success Story
Part 4 - Something My Body Needs Anyway?
Part 5 - Obesity's Elephant: Environmental Chemicals
Part 6 - Why Our Approach to Toxicology Must Change
Part 7 - Failures of U.S. Chemical Regulation
Part 8 - Cleaning Up Our Act
Part 9 - Environmental Health Research Saves Lives and Money
Part 10 - Call to Action
Thursday, May 13, 2010
Failures of U.S. Chemical Regulation
In previous posts, I've shared how research demonstrates a link between endocrine disrupting chemicals (EDCs) and negative health effects, such as obesity. Since EDC exposures are a health concern, the government needs to identify chemicals of concern and implement policies to reduce exposures, as was done for lead. Unfortunately, U.S. chemical regulation is not a straightforward process.

This fragmented regulation makes it difficult to protect public health. But there were also a large number of chemicals in commerce that were initially unregulated if they were not covered under other existing laws, such as the Federal Food, Drug, and Cosmetics Act which regulates pharmaceuticals. In an attempt to close this gap, Congress passed the Toxic Substances Control Act (TSCA) in 1976, which gave EPA the authority over all unregulated chemicals.
A major flaw is that TSCA treats new chemicals differently than chemicals that existed before the act. Existing chemicals were not evaluated and were just presumed safe. At the time TSCA passed, there were already about 62,000 chemicals in commerce. Regulation of new chemicals isn’t much better and has limited requirements. Companies are only required to submit available data and don’t have to test for toxicity. It is estimated that only 15% of new chemicals have complete health and safety data.

TSCA was introduced over 30 years ago. Today, there are over 80,000 chemicals approved for use in the products we use, such as household cleaners, shampoo, and makeup. But to date, the EPA has only been able to regulate 5 chemicals and require testing for about 200. I feel the numbers clearly show that TSCA has failed to protect Americans.
This is Part 7 in the Chemical Exposures and Public Health series.
Part 1 - From Interest to Passion
Part 2 - An Environmental Health Risk
Part 3 - Lead: A Regulatory Success Story
Part 4 - Something My Body Needs Anyway?
Part 5 - Obesity's Elephant: Environmental Chemicals
Part 6 - Why Our Approach to Toxicology Must Change
Part 7 - Failures of U.S. Chemical Regulation
Part 8 - Cleaning Up Our Act
Part 9 - Environmental Health Research Saves Lives and Money
Part 10 - Call to Action
Tuesday, May 11, 2010
Why Our Approach to Toxicology Must Change

Research has shown that chemicals in a mother's body are able to cross the placenta, and therefore, children are being exposed to environmental chemicals even while they are in the womb. As infants, they are exposed to chemicals at higher levels because consume more food relative to body weight, but also because their immune systems are less developed, and therefore, less able process and remove chemicals from their bodies.
For lead, proper regulation took several decades because we initially had a poor understanding of its health effects. We face the same problem today with EDCs.
To determine safe exposure levels, animals are exposed to varying amounts of a chemical and a dose that does not produce observable effects is identified. Then, a series of uncertainty factors are applied to that dose in order to calculate an acceptable level for human exposure. The uncertainty factors account for different sensitivities between the animals studied and humans but also to account for varying sensitivities between humans.
So, what is wrong with the current approach?
Scientists who study the endocrine system have recognized for a while that hormones have a different relationship between dose and effect. Hormones and hormone mimicking chemicals, like EDCs, can produce opposite effects at different exposure levels. A low level exposure can turn a process on, while a high level exposure could shut the process off.
Since EDCs have a different dose-effect relationship, the current assumptions used in toxicology studies are outdated. High-dose experiments can not be effectively used to predict low-dose results for EDCs, and therefore, safety testing needs to be adapted to make sure that potential low-dose effects are investigated. In order to address our evolving understanding of endocrine disruption, the Endocrine Disruptor Screening Program was established by the Environmental Protection Agency to develop a battery of tests to properly identify EDCs, information that will enable us to update the way we conduct toxicology studies.
The scientific understanding of how endocrine disruption can be identified and measured is still in the early stages, and research will be our best chance to close these knowledge gaps and identify chemicals that are a real public health threat.
This is Part 6 in the Chemical Exposures and Public Health series.
Part 1 - From Interest to Passion
Part 2 - An Environmental Health Risk
Part 3 - Lead: A Regulatory Success Story
Part 4 - Something My Body Needs Anyway?
Part 5 - Obesity's Elephant: Environmental Chemicals
Part 6 - Why Our Approach to Toxicology Must Change
Part 7 - Failures of U.S. Chemical Regulation
Part 8 - Cleaning Up Our Act
Part 9 - Environmental Health Research Saves Lives and Money
Part 10 - Call to Action
Monday, May 10, 2010
Obesity's Elephant: Environmental Chemicals

Endocrine disrupting chemicals (EDCs) are a public health concern because they mimic natural hormones and interfere with our endocrine system. Research shows a potential link between children being exposed to EDCs during development and the increased burden of chronic health problems, such as obesity.

The reason BPA is becoming a public health concern is that research has demonstrated a link between children's exposure to BPA during critical developmental windows - such as in the womb or as infants - and obesity. For example, Nikaido et al. exposed pregnant rats to BPA to determine the effects on fetal development [1]. The results showed that prenatal exposure to BPA at human-relevant doses accelerated weight gain of the female offspring compared to offspring of the mothers not exposed to BPA.
This study is one of many that demonstrate chemical exposures could be a factor, changing our bodies in ways that make us obese.
References
1. Nikaido, Y. et al. Reprod. Toxicol. 2004; 18: 803-811.
This is Part 5 in the Chemical Exposures and Public Health series.
Part 1 - From Interest to Passion
Part 2 - An Environmental Health Risk
Part 3 - Lead: A Regulatory Success Story
Part 4 - Something My Body Needs Anyway?
Part 5 - Obesity's Elephant: Environmental Chemicals
Part 6 - Why Our Approach to Toxicology Must Change
Part 7 - Failures of U.S. Chemical Regulation
Part 8 - Cleaning Up Our Act
Part 9 - Environmental Health Research Saves Lives and Money
Part 10 - Call to Action
Friday, May 7, 2010
Something My Body Needs Anyway?
The impact of environmental chemicals on health is becoming a defining concern of this century. I’m sure you’ve seen the increasing number of articles published by the mainstream media questioning the safety of chemicals in consumer products, like plastics. Research has shown that these chemicals are getting into our bodies and can mimic our hormones.
Hormones are signals that regulate biological processes by communicating messages to cells. Hormones bind to a receptor like a key fits into a specific lock, which tells the cell to carry out a specific action.
One example is human growth hormone. As children, growth hormone is released in our body to tell limbs and organs to grow. But when we become our adult size, our body stops releasing the growth hormone, so the cells are no longer receiving the message to grow. Hormones are regulated by a group of glands called the endocrine system.
Certain unnatural chemicals entering our bodies can mimic our natural hormones. They are called endocrine disrupting chemicals (or EDC) because of their ability to interfere with our endocrine system.

The problem with EDCs is that they are not made by your body, and therefore, your body is not able to regulate EDCs like it regulates your natural hormones. But at the same time, EDC’s (green) can bind to the receptors (purple) of specific natural hormones (orange), initiating the same cell response. Research suggests that EDCs artificially switching processes on and off and at the wrong time is contributing to the rising burden of illness in America.
I am particularly interested in EDCs because we are just now discovering the sheer number of chemicals that have the ability to act this way, but we don’t yet know which chemicals, or at what exposure levels, are linked to which real public health threats.
The government again needs to decide if regulatory action is necessary, a decision that depends largely on whether the chemicals pose a threat to U.S. health.
This is Part 4 in the Chemical Exposures and Public Health series.
Part 1 - From Interest to Passion
Part 2 - An Environmental Health Risk
Part 3 - Lead: A Regulatory Success Story
Part 4 - Something My Body Needs Anyway?
Part 5 - Obesity's Elephant: Environmental Chemicals
Part 6 - Why Our Approach to Toxicology Must Change
Part 7 - Failures of U.S. Chemical Regulation
Part 8 - Cleaning Up Our Act
Part 9 - Environmental Health Research Saves Lives and Money
Part 10 - Call to Action
Wednesday, May 5, 2010
Lead: A Regulatory Success Story
Today, we know that lead exposure is a problem for children’s health, but this wasn’t always the case. Research evolved the scientific understanding of lead poisoning, which can be broken down into four stages [1].
- Children assumed not to be affected by lead
- Cases of acute lead poisoning were identified but were thought to result in either death or recovery
- Lasting mental deficits only occur when children had clinical symptoms of lead poisoning
- Children without clinical symptoms can still have mental deficits in language, IQ, or attention

There were two major sources of lead exposure for children: leaded gasoline and lead paint.
Lead was a standard additive in gasoline, but in 1965, research demonstrated that the increased lead concentrations in the air were the direct result of human activities, like burning leaded gasoline. This clear link between air quality and health was why Paul Rogers led the fight to pass the Clean Air Act. Passage of the Clean Air Act paved the way for the phase-out of lead in gasoline by 1996.
Lead based paints were commonly used in homes in the early 1900s. Research linking lead exposure to children's health effects prompted a 1978 federal limit on the lead content in paints used in residential buildings.
Together, these policy actions were extremely successful at reducing lead exposure. Banning leaded gasoline reduced the average air lead concentration by 94%. This ban, in conjunction with the limit on the lead content in paint, reduced the average blood lead level in children more than 7 times below the 1970s level.
This reduction in the United States is estimated to have resulted in an economic gain between $110 and $319 billion dollars for children born in a given year [2]. This economic gain was calculated using the increased worker productivity that will result from the improved cognitive ability of children with lower lead exposures.
Lead regulation is a great example of how research can lead to policy changes that can benefit public health and save money.
References
1. H. Needleman. Annu. Rev. Med. 2004; 55: 209-222.
2. Grosse, S.D. et al. Environ. Health Perspect. 2002; 110: 563-569.
This is Part 3 of 10 in our Chemical Exposures and Public Health series.
Part 1 - From Interest to Passion
Part 2 - An Environmental Health Risk
Part 3 - Lead: A Regulatory Success Story
Part 4 - Something My Body Needs Anyway?
Part 5 - Obesity's Elephant: Environmental Chemicals
Part 6 - Why Our Approach to Toxicology Must Change
Part 7 - Failures of U.S. Chemical Regulation
Part 8 - Cleaning Up Our Act
Part 9 - Environmental Health Research Saves Lives and Money
Part 10 - Call to Action
Tuesday, May 4, 2010
An Environmental Health Risk
How often do you think about the chemicals in products you buy and if they could affect your health? We use a number of products every day from shampoo to cleaning products and we expect that the government regulates these products to make sure they are safe.
Unfortunately, in the past, certain chemicals have been discovered to affect our health only after they reached the market, as was the case for lead paint. Today, this is happening again with a group of compounds called endocrine disrupting chemicals, which mimic our hormones.
WWII increased demand for products, resulting in the development new uses for natural chemicals, which exposed us at higher levels, and the acceleration of the production of chemicals not previously found in nature. But no one thought about potential effects on our health, until Rachel Carson published Silent Spring. Her book raised awareness that chemicals could interact with our bodies.
Carson published evidence that the pesticide, DDT, had put the bald eagle on a path towards extinction, and if it was hurting wildlife, it could potentially be harmful to humans as well. DDT was considered a miracle pesticide and was used for everything from combating malaria to protecting cotton. However, Carson's book spurred national action that ultimately led to a ban of DDT.
Silent Spring was the beginning of an environmental movement, which I'll share some results of in more detail tomorrow.
This is Part 2 of 10 in our Chemical Exposures and Public Health series.
Part 1 - From Interest to Passion
Part 2 - An Environmental Health Risk
Part 3 - Lead: A Regulatory Success Story
Part 4 - Something My Body Needs Anyway?
Part 5 - Obesity's Elephant: Environmental Chemicals
Part 6 - Why Our Approach to Toxicology Must Change
Part 7 - Failures of U.S. Chemical Regulation
Part 8 - Cleaning Up Our Act
Part 9 - Environmental Health Research Saves Lives and Money
Part 10 - Call to Action