Could Environmental Radiation Be Contributing to Your Thyroid Disorder?

Despite its miniscule dimensions, the tiny thyroid gland plays an outsize role in determining the healthy functioning of the human body. Among its many unique qualities, the thyroid gland has a very high level of sensitivity to radiation in the environment.

Before the twentieth century, the thyroid gland's unusual sensitivity to radiation was not recognized. But as mankind gained the once-unimaginable power to manipulate atoms and handle radioactive materials, ushering in the advent of technologies as diverse as x-rays, radiation therapy, and atomic weapons, this unique property was suddenly thrown into sharp focus.

The thyroid gland absorbs iodine from the bloodstream. However, the gland cannot distinguish between stable iodine and radioactive iodine. As such, in the aftermath of a radioactive explosion or another type of exposure to environmental radiation, the thyroid gland often serves as the suppository for the absorbed substance.

Some scientists have posited that the thyroid's unique ability to store radioactive iodine may be the cause of the dramatic increase seen in thyroid cancer diagnoses in recent years. Although the debate over the significance of environmental radiation continues to range among the endocrinology community, researchers around the world are working to assess the environment's impact on thyroid health. This week, we'll review a few of the key findings that have been reported in recent months.

Study Shows How Radiation Exposure Causes Illness and Injury

While it has long been recognized that radiation exposure often has deleterious health effects, the precise pathways of radiation damage in the body have remained shrouded in mystery. However, the results of a recent study conducted by scientists at renowned research institute MIT have helped to shed more light on the link between radiation and several significant illnesses, including thyroid disorders.

According to the study, a new technique that has been devised can pinpoint with great precision the sites at which radiation damage has occurred. The advanced imaging technology involves the injection of boron into the bloodstream. Then, a special tool is used to temporarily irradiate the body, illuminating areas of damage.

Based on preliminary findings, changes in tissue structure and cell function are the earliest indications of radiation exposure that can eventually cause cancer or other illnesses. Although more investigation is necessary to confirm these findings, the researchers noted that the new technique may be used to develop radiation therapies that are not as invasive or harmful as current methods.

Scientists Study Risks of Secondary Cancer in Patients Who Have Undergone Radiation Therapy

Thanks to numerous medical advances, the survival rates for many types of cancer are now higher than ever. However, these successes have given rise to a number of unforeseen issues -- including an increased risk of secondary cancer among long-term cancer survival. In other words, a growing number of patients who have survived a first bout with cancer are later developing tumors and cancers thought to be caused by radiation therapy.

A team of researchers recently undertook a large-scale analysis of the scientific findings pertaining to radiation-based secondary cancers, the results of which were detailed in the latest volume of the journal Radiation Research. According to their findings, although there does seem to be a clear health risk associated with radiation-based cancer therapy, there is too much variance between treatments and individual cases to derive any sweeping conclusions from the epidemiological patterns.

However, the team did note that one clear recommended change in protocol emerged from the research -- the risk of secondary cancer was decreased considerably when the dose is held to a maximum of ~0.1 Gy. The scientists urged medical professionals who treat cancer patients to keep these guidelines in mind when designing courses of radiation therapy.

Survivors of Atomic Bomb Deployment and Testing Show Higher Incidences of Thyroid Cancers and Other Thyroid Disorders

From the first detonation of an atomic bomb, it was recognized that these weapons were capable of causing destruction on a scale never before imagined. However, what was not initially understood were many of the long-term health problems that would plague those exposed to the blast.

Follow-up studies conducted on populations of survivors who were exposed to wartime blasts and pre-war bomb tests now indicate a sharply increased risk of thyroid cancer and other thyroid disorders among these groups. A recent study of Japanese survivors of the Hiroshima bomb showed thyroid cysts, tumors, and other cancerous growths that far outpaced the rates seen in the general population. Tests on survivors and survivors' descendants in the region of the Chernobyl accident site have revealed similar findings.

Among survivors who withstood first-hand exposure to a bomb blast, thyroid tumors were most likely to occur 55-58 years after exposure. Furthermore, the Hiroshima data showed that the younger the individual was at the time of exposure, the higher their risk was of developing cancer later in life. This result was also found to hold true in tests done around the Chernobyl site. The authors of the study emphasize the importance of monitoring the thyroid health of those exposed to radiation, particularly infants, children, and young adults.

If you're concerned about the role environmental radiation may be playing in your thyroid health, consult with your physician for a personalized risk profile. Please check back each week for more of the research news you need to achieve optimal thyroid health.

Environmental Threats to Thyroid Health: Recent Findings and an Action Plan for Prevention

Thyroid function is an enormously complex bodily process that researchers are only just beginning to fully understand. Even minor variations in the thyroid’s ability to do its job properly can cause major health problems. As a result, recent studies have sought to pin down the factors and variables that are behind the most common thyroid problems and disorders.

In many cases, it appears that thyroid-related illnesses stem from within the body itself. Normal hormonal fluctuations that occur over the course of a lifetime, such as childbirth and menopause, can upset the delicate balance of the endocrine system and increase the risk of thyroid dysfunction. Other types of imbalances in the body can also foster thyroid problems, as well.

But some researchers are beginning to consider factors outside of the body as possible causes of thyroid problems. Due in large part to the rapid influx of man-made pollutants and impurities that have been released into the atmosphere in the last century, our environment is rapidly changing.

A growing number of scientists believe that these changes may also impact the thyroid’s ability to function properly. According to some preliminary hypotheses, these environmental influences could account for the sudden increase in some thyroid-related illnesses that has been observed in recent years. Most notably, the reported rate of thyroid cancer has more than doubled over the course of the last several decades.

Recent Findings Illuminate the Thyroid-Environment Relationship

Over the course of the last several decades, hundreds of studies have been conducted seeking to identify the nature and extent of the relationship between different environmental factors and thyroid conditions. Although numerous connections have been found, the three chief environmental culprits believed to cause or worsen thyroid disorders are pesticides, chemical compounds, and radiation.

In the twentieth century, the quest to perfect the mass production of food led to the development and introduction of a number of increasingly potent pesticides. After years or even decades of use, some of the most widely-applied pesticides have subsequently been linked to health problems and taken off the market.

Health problems that are related to pesticides often take many years to become fully apparent. Scientists suggest that we are still discovering some of the long-term health impacts of the pesticides that were widely used in the past.

Several studies have suggested a link between pesticides in current and past usage and thyroid problems. Of particular concern are ethylenebisdithiocarbamates, commonly referred to as EBDCs. These potent fungicides are sprayed on fruits, leafy vegetables, and some grains to prevent the growth of crop-destroying fungi.

Since the 1960s, EBDCs have been linked with thyroid disorders, such as decreasing the body’s natural ability to take in iodine and increasing the risk of goiters. Although the results are somewhat inconclusive, pesticides in this class have also been linked to thyroid cancer in rats and mice.

The mass production of consumer goods has led to a rapid increase in the number of manmade chemical compounds that have been released into the environment as the byproduct of manufacturing processes. Several manmade chemical compounds have been linked to thyroid disorders, with PCBs and perchlorate identified as two of the most potentially harmful substances.

Although polychlorinated biphenyl (PCB) has been banned in the United States since 1979, these potent chemicals, once used to manufacture electrical components, have been shown to have accumulated in many areas of the natural environment. Exposure to excessive PCB levels can disrupt the balance of the hormones released by the thyroid, causing improper function of the endocrine system. PCBs have also been linked to a heightened overall risk of cancer.

Perchlorate is an oxygen-based compound that is used in the process of synthesizing rocket fuel. This chemical is often found in the water supplies of areas of the United States that have supported the development of space travel technology, with the highest concentrations seen in the American Southwest. Like PCBs, perchlorate inhibits the thyroid’s ability to take in sufficient levels of iodine, causing slow thyroid function and, in some cases, goiter development.

Radiation has long been known to be a source of thyroid disorders, but over the course of the twentieth century, the amount of environmental radiation most people are exposed to on a daily basis has increased considerably. Large-scale radiation releases such as the Chernobyl nuclear reactor disaster in Russia and the atomic bomb deployment in Hiroshima and Nagasaki, Japan, have both been linked to the most severe risks of thyroid cancer and other thyroid related diseases.

Today, however, scientists are beginning to expand the scope of their search for the impact of environmental radiation on thyroid diseases. In addition to nuclear testing and bomb deployment, researchers are now considering the impact of significant x-ray exposure or living in close proximity to manufacturing or test facilities where radiation is emitted. It is believed that future studies will further expand our understanding of the impact of environmental radiation on thyroid problems.

Action Plan: Reduce Your Risk of Environmental Exposure

Because we are still discovering environmental factors and variables that can negatively impact thyroid health, it’s virtually impossible to completely eliminate the possibility that your thyroid function will suffer from unseen elements in your surroundings. However, by following a few simple guidelines, you’ll be able to significantly decrease your risk of experiencing environmentally-related thyroid problems.

• Opt for organic produce. If organic produce supplies in your area are scarce or too costly, you can still reduce your risk by thoroughly scrubbing all fruit and vegetables to remove pesticide residue.

• Filter your water. Invest in the highest-grade filter system you can afford in order to remove chemical compounds from your tap water. Whether it’s a faucet unit or a stand-alone system, you’ll be reducing your intake of compounds that can be hazardous to your health.

• Buy biodegradable. By looking for products that are ecologically sound, you’ll not only be helping the environment, but you’ll also reduce your exposure to potentially harmful chemicals.

• Limit x-rays. Today, most diagnostic x-rays are conducted in a very safe manner, but it’s still smart to question their necessity if the number of trips you’re asked to take to the radiologist starts to seem like it may be excessive.