by Erica Elliott, M.D.

Beginning in the last half of the twentieth century, there has been a growing epidemic of allergies and other immune system problems related to the rising levels of petrochemicals and heavy metals in our food, air, and water and the simultaneous decline in the nutritional content of the food we consume. Recognizing that mainstream medicine had not been addressing this serious issue, a group of clinicians from various specialties banded together in 1965 and formed a medical society that eventually evolved into the American Academy of Environmental Medicine.

Definition of this healing system Environmental medicine is concerned with the interaction between an individual and the environment. This branch of medicine integrates the concepts drawn from primary and specialty care medical fields, with the basic sciences. Physicians who practice environmental medicine are trained in the recognition, treatment, and prevention of illnesses induced by exposures to biological, physical, and chemical agents encountered in air, food, and water.

This system of healing offers a reinterpretation of medical thinking, especially in its approach to many previously unexplained and ineffectively treated chronic diseases. The emphasis in environmental medicine is on a broad based search for and correction of the underlying causes of disease. Unlike most fields of medicine, the search includes an evaluation of diet and nutritional status, as well as chemicals, mycotoxins, and heavy metals in the environment and their impact on health. Environmental medicine physicians recognize that what we eat or are exposed to in our environment may have a direct and profound effect upon our emotional and physical health.

Some of the basic theories of environmental medicine include total load, individual susceptibility, adaptation, and masking.

Total load refers to the total number of environmental stressors acting on an individual at any one time which contribute to the breakdown of that person's homeostatic mechanisms. Rarely is there only one offending agent responsible for causing symptoms. Multiple factors co-exist, frequently over a prolonged period of time, in bringing about the disease process. Some of these factors include nutritional deficiencies, toxic chemical exposures, heavy metal overload, infections, recurrent use of antibiotics and other drugs, surgery with general anesthesia, hormone imbalances, and emotional stress.

Individual susceptibility refers to the concept that some people are more vulnerable to disease than others. This variability occurs for a variety of reasons including genetic predisposition, gender, nutritional status, levels of exposure to offending substances, concurrent infections, and emotional and physical stress. It is common knowledge, for example, that not all people exposed to the cold virus will get a cold. What is less well known is that diseases can manifest differently in different people because of variations in biochemical individuality. If, for example, after the remodeling of an office building using standard building products, ten workers are exposed to the same amount of formaldehyde and other toxic fumes, not everyone will develop the same symptoms. One worker might develop depression, one arthritis, one sinusitis, one diarrhea, one asthma, while five may remain apparently unaffected. 

Adaptation is an acute survival mechanism which allows an individual to "get used to" an acute toxic exposure in order to initially survive it. The first stage of adaptation is the alarm stage in which an individual perceives a causal relationship between an exposure and the development of symptoms. Without intervention, the adaptation process continues to the second stage known as "masking". Body functions undergo adjustments in an attempt to accommodate this exposure. Over time, adaptation that accompanies continued exposure to toxic substances can lead to the third stage in which the body's biologic mechanisms or systems have been overwhelmed and are not able to maintain homeostasis. It is at this stage that symptoms of illness occur. This phase is also know as maladaptation. In its most severe form, the third stage can lead to end organ failure.

Masking is a term used to describe the tolerance that develops to a toxic substance. For example, an individual briefly exposed to cigarette smoke may cough and get burning eyes with a runny nose (alarm phase). If the individual begins to smoke regularly, he will adapt to the cigarette smoke and no longer have those symptoms, even though the smoke will still be causing damage (masking phase). Because an individual is unable to recognize the acute effects of toxic exposures during the adaptation phase, he may intentionally or unintentionally continue to expose himself to pollutants that enter and accumulate in his body. These substances contribute to an increased total body load and depletion of nutrients as his body tries to counteract this build-up. As the smoking persists, however, the individual will begin to develop more severe tissue changes in the respiratory tract, leading to respiratory symptoms. In the final stage, lung damage may become permanent (maladaptation).
An Environmentally-oriented Approach to a Common Ailment---Depression

Since the 1940's, the incidence of clinical depression has markedly increased in developed countries. Major depression accounts for up to 8% of patients seen by family doctors in the past decade. This illness affects nearly 9 million people annually, according to the American Psychiatric Association. The actual numbers of people with depression are probably higher since depression often goes undiagnosed.

In the standard medical practice, most patients with depression are prescribed a mood altering drug and frequently referred to a psychiatrist. Environmental medicine recognizes that the dichotomy between physical and mental illness is artificial and that psychiatric symptoms, including depression, may be a manifestation of an underlying physical illness. What follows is a brief overview of depression from the broader perspective of an environmental physician.

The criteria for diagnosing depression are delineated in the Diagnostic and Statistical Manual of Mental Disorders. There needs to be a minimum of 5 of the following criteria to make a diagnosis of depression:

• A continuously depressed mood for a minimum of two weeks. Children and adolescents can manifest depression with chronic irritability.
• Unrelenting fatigue
• Difficulty with concentration and decision-making
• Loss of interest in most activities
• Change in sleep patterns (insomnia or excessive sleep)
<;li>Unintentional loss or gain in weight
• <;span style="color: #58583c; font-size: 14px;">Psychomotor agitation or retardation
• Feelings of helplessness, hopelessness, and guilt
• Recurrent thoughts of death or suicide

Most physicians are well schooled in the kind of depression that occurs as a response to emotional issues such as grief after a loss or unexpressed anger. In the last two decades we have also been trained to view depression as a biochemical abnormality. The standard treatment is referral to a psychiatrist and a prescription for a mood altering drug. The search for the underlying cause of the biochemical abnormality is rarely pursued. By only treating with psychiatric drugs and not identifying the contributing causes of depression, the person's overall condition may worsen rather than improve.

How are signs and symptoms of depression viewed from the perspective of this healing system?
There are numerous environmental triggers that can cause depression. A common and frequently overlooked cause of depression is exposure to neurotoxic chemicals. These chemicals have been implicated in causing or exacerbating psychiatric, cognitive, and somatic disorders. Many of the everyday chemicals found in the average home, school, or office are neurotoxic and have the potential to cause depression. A neurotoxic chemical is a substance that is harmful or poisonous to the nervous system. Chronic, low-level exposures to these environmental neurotoxins can be as harmful as acute high level exposures. Sometimes the neurological damage is subtle and may be incorrectly attributed to other conditions such as psychiatric illness or advancing age. There are remarkably few practitioners in the field of medicine who are trained in the neurological, behavioral, and psychiatric effects resulting from chemical exposures. And there is also little public awareness that toxic chemicals in commercial products can affect mood and brain function.

More than 850 chemicals have been identified as producers of neurobehavioral disorders. Neurotoxic chemicals can be found in such common household products as pesticides, paints, sealers, glues, new carpeting and other building materials and furnishings, perfumes, air fresheners, and many cleaning products. In the workplace, it has been estimated that in the United States alone, over nine million individuals are exposed to neurotoxins.

Depression is one of the most common symptoms associated with exposure to neurotoxins. Most of the neurotoxic chemicals fall into the categories of solvents, chlorinated hydrocarbons, pesticides and heavy metals. These chemicals are capable of crossing the blood brain barrier and have the potential to interfere with brain function. They can up- or down-regulate neurotransmitter synthesis, block receptor sites, and poison essential enzymes used in neuronal metabolism. Subjects exposed to volatile organic compounds (see glossary for definition of VOC's), for example, have displayed extreme personality disturbances, rages, insomnia, mood swings, and depression. Other reported symptoms include extreme fatigue and decrease in cognitive abilities, e.g., problems with short-term memory, inability to concentrate, episodes of confusion and mental slowness. Mental and emotional dysfunction from chemical exposures may develop so gradually that they can go unnoticed for years. On the other hand, there are times when the onset of environmentally-triggered depression can be clearly recognized, for example, after an application of a pesticide or the installation of new carpeting.

Heavy metal poisoning is a common form of environmentally-related disease. Heavy metals include mercury, lead, tin, cadmium, and aluminum. Metals can cause acute or chronic toxicity. They can be inhaled as fumes or dust particulates, absorbed through the skin, and ingested in food or water. Chronic toxicity occurs with small doses that accumulate over a long period of time and is much more difficult to diagnose than acute toxicity. One of the manifestations of metal-induced neurotoxicity can be depression. Severe mood disturbances, learning disabilities, and dementia can also be caused by chronic heavy metal exposure. An important source of chronic heavy metal exposure is from dental amalgams that contain mercury.

Hidden food allergies are one of the least diagnosed and most frequent causes of symptoms. These symptoms can range from fatigue, headaches, and irritability to exacerbation of arthritis, ulcerative colitis, and seizures. Food allergy can mimic nearly any symptom or disease. Depression is one of the leading symptoms of food allergies. Instead of hives or runny nose, the food allergy can present as a depressive mood, feelings of rage, panic attacks, or even schizophrenia. Patients with long-standing physical and mental symptoms who have not been helped by many years of conventional medical treatment have been noted to experience immediate relief when they have avoided certain foods.

Nutritional deficiencies are an important but often ignored aspect in the evaluation of treatable causes of depression. Even for those who follow an ideal diet, the heavy exposure to environmental stressors often requires additional supplementation of nutrients. When nutrients are deficient, the detoxification pathways will not operate normally and symptoms can develop. These nutrients include vitamins, minerals, amino acids, fatty acids, and antioxidants. The average American eats a diet that is low in nutrients. The diet is characterized by a high intake of sugar and hydrogenated fats, minimal intake of vegetables, and refined and processed foods devoid of nutrients and full of additives. Making certain dietary changes can have a dramatic effect on mood disorders.

Mold exposure is another frequently overlooked cause of depression. Molds are everywhere in the environment. They are invisible, microscopic organisms that cannot be seen until they have grown into large colonies, but can cause symptoms even when not detected by the naked eye. Molds can produce mycotoxins. These substances can be as toxic as some of the most hazardous synthetic chemicals. Mold has the potential to affect any target organ, including the brain. In fact, exposure to mold can be the primary cause of depression and other severe mood disturbances. Some other common symptoms produced by mold exposure are headaches, fatigue, burning eyes, and inability to concentrate.

Hormone imbalance is another cause of depression. The endocrine system is composed of seven glands that work together to keep the body in balance and running smoothly. They are the pituitary, pineal, thymus, thyroid and adrenal glands, and the gonads and the pancreas. The malfunction of any of them can lead to mood disorders such as depression. Some examples follow.

Hypothyroid disease can cause depression. Hypothyroidism is common in older women and frequently goes undiagnosed.
Researchers have observed that fluctuating levels of estradiol, progesterone, and testosterone exert profound effects on mood and mental states.
Fluctuating blood sugar levels is another common cause of mood swings and depression.
Abnormalities of circadian function of melatonin have been closely linked to a variety of behavioral changes and mood disorders. Studies have reported decreased nocturnal melatonin levels in patients suffering from depression. In seasonal affective disorder (SAD), melatonin secretion tends to be elevated.
A disruption in the circadian rhythm of cortisol has been found in some depressed patients. They typically have significantly higher morning and midnight salivary cortisol levels.
Occult infections can cause fatigue and depression. Intestinal yeast and parasites are a common source of undiagnosed infections. Yeast infections can produce a wide range of symptoms including difficulty concentrating, mood swings, bloating, food intolerances, addiction to sweet foods, headaches, and irritability.

Diagnostic Methods

Taking a history
Primary care physicians are well-trained in the recognition of clinical depression. Most physicians, however, have not been trained to look for underlying causes of these biochemical abnormalities. To determine whether there is an environmental cause of the patient's depression, a chronological and sufficiently detailed history is of utmost importance. The practitioner needs to be knowledgeable about common toxins in the indoor and outdoor environment and their short and long-term effects on the nervous system in order to ask the appropriate questions. The following are a few examples of the kinds of questions that are critical in uncovering some of the underlying organic causes of depression:

• How long have the symptoms been present?
• Was the onset sudden or gradual?
• What was going on at the time of onset of the depression?
• What medications are being taken? Supplements? Herbs?
• What other medical problems are there?
• Have there been past surgeries or hospitalizations?
• What medical problems run in the family?
• Are there any other symptoms or conditions present such as allergies, asthma, joint and muscle pains, chronic sinus infections, headaches, stomach aches, gas and bloating, chronic diarrhea or constipation, cramps, abnormal menstrual bleeding, rashes, seizures, mood swings, difficulties with short-term memory, episodes of confusion, numbness and tingling in the extremities?
• Are there food cravings?
• What foods are typically eaten every day?
• How much alcohol is consumed?
• How many hours are spent asleep each day?
• Where is the home, school, or workplace located? Is there agriculture, industry, or other sources of contamination located nearby?
• Has there been a recent move to a new home or recent remodeling?
• Have insecticides or herbicides been used at the home or workplace?
• Has there been new carpeting installed at home or in the workplace?
• What kind of exposures to fumes are there in the home and workplace?
• Are there any water leaks or areas of increased moisture or evidence of mold at home or work?
• What kind of hobbies are there?
• Does anyone else at home, school, or work have symptoms?
• Is there a pattern to the depression? Are there times when the symptoms feel better or worse?

Testing

A preliminary diagnosis can often be made from the history alone. A focused physical exam, based on the symptoms, can give additional information. The diagnosis of a chemical-based etiology is confirmed when avoidance of the suspected toxin eliminates or reduces the symptoms, and re-exposure brings them back. Other useful testing follows.

• Indoor air quality testing for home, school, or office. The evaluation should include use of pesticides, detection VOCs from new carpeting, gas leaks, formaldehyde from building materials, water leaks, mold, electromagnetic fields, and a thorough check of the air ducts and other systems of ventilation, among other things.
• 
  
• Intra-dermal provocation and neutralization testing (see glossary for explanation of this method of testing) can be done by physicians trained in environmental medicine. During testing, symptoms are reproduced, then neutralized with the appropriate dilution. (Skin testing in the classical allergy method is not helpful because most cases of chemical sensitivity is not IgE mediated.) .
• Blood levels of chemicals can be measured, but a negative result does not rule out neurotoxicity. In most cases the chemicals are no longer present in the blood or are too low to measure. (Accu-Chem Labs)
• 
  
• Antibody testing to specific chemicals such as benzene or formaldehyde can sometimes be useful. The presence of these antibodies indicates an immune response to the chemicals. (Immunosciences Lab)
• 
  
• Heavy Metal testing. Begin with a screening test with a hair analysis. More accurate testing can be done with stool and urine collection after provocation with a chelating agent. (Doctor's Data Lab)
• 
  
• Comprehensive Detoxification Profile analyzes saliva, blood, and urine after challenge doses of caffeine, aspirin, and acetaminophen, in order to assess the Phase I and Phase II functional capacity of the liver to convert and clear toxic substances from the body. (Great Smokies Diagnostic Labs)
• 
  
• Oxidative Stress Analysis identifies markers of hydroxyl radical activity, urine lipid peroxides, reduced glutathione, superoxide dismutase, and glutathione peroxidase, following a challenge dose of aspirin and acetaminophen. Long term exposure to toxins may lead to oxidative stress. (Great Smokies Diagnostic Lab)
• 
  
• Testing of nutritional status, including vitamin, mineral, antioxidants, and fatty acid levels. (ION panel from MetaMetrix Lab)
• 
  
• Brain imaging with single photon emission computerized tomography (SPECT scan) can detect central nervous system damage that is consistent with neurotoxicity.
• 
  
• Neuropsychological testing is helpful in detecting neurotoxic brain dysfunction accompanying the depression.

Food Sensitivities

The identification of food sensitivities can be difficult since many reactions are delayed and can occur many hours after the offending food has been eaten. In addition, reactions can be masked if the food is eaten every day. Therefore, the patient is often unaware of the foods to which he is sensitive and may even be unaware that his symptoms are due to food intolerances. Often the most allergenic foods are the ones that are craved the most, as there seems to be a link between allergy and addiction.

There are several ways to test for food allergies, but each method has its limitations. The traditional skin testing by classical allergists only tests for an IgE response which accounts for only a small percentage of reactions to foods. There is a food allergy blood test that checks for IgG antibodies (Great Smokies Diagnostic Lab). These antibodies mediate some of the delayed allergenic responses to foods. This test is limited by the fact that it does not reveal food intolerances or sensitivities that are mediated by other immune or non-immune pathways.

Serial Dilution Provocative Food Testing is performed by introducing a small amount of a potent food extract into the circulation by injection or sublingual drops. When a test is positive, it usually reproduces symptoms within ten minutes after the administration of the first or second dilution. These tests are administered in the offices of most physicians practicing environmental medicine.

One of the most accurate methods of determining food sensitivities is the elimination diet. There are several methods for doing this test. One method requires a complete fast for 3 days under controlled conditions where other environmental exposures are avoided. After withdrawal reactions have subsided and chronic symptoms cleared, individual foods are reintroduced one at a time and the patient is observed for any reactions.

A more user friendly elimination diet that I use in my practice has been termed "the Stone Age diet". It excludes the foods that most commonly cause adverse reactions. These are foods containing gluten (wheat, oats, rye, and barley), dairy products, eggs, corn and soy products, sweet foods, especially refined sugars, and all processed foods containing additives, preservatives, and dyes. The diet includes meat, fish, fresh vegetables, avocadoes, nuts and seeds, and a limited amount of fresh fruit, all organically grown if possible. These foods must be unprocessed. They can be eaten either cooked or raw. The foods should be rotated as much as possible. This means that the same foods should not be eaten every day. The diet needs to be followed for one week. Then, if symptoms have cleared, the excluded foods are reintroduced, one new food every other day. The patient is advised to keep a journal to document any symptoms that arise. During the period of avoidance it is not uncommon to have withdrawal symptoms which usually clear by the end of the third day. Withdrawal symptoms following cessation of a food suggest the presence of a possible allergy or intolerance to that food.

Once it is determined which foods cause symptoms, the patient is advised to eliminate the foods causing the worst symptoms and to rotate the foods causing little or no symptoms. A four day schedule is necessary for some severely allergic patients, but other people can tolerate eating foods more frequently. The patient may eventually be able to tolerate small amounts of allergenic foods after they have been avoided for 6-12 months. However, if the foods in question continue to be eaten more frequently than every fourth day, the symptoms may return.

Most medical conditions will benefit from a diet that contains whole foods (preferably organic) that includes a large variety of fresh vegetables and fruits, non-hydrogenated oils, raw nuts and seeds, a limited amount of simple carbohydrates, and filtered water instead of coffee, alcohol, and sodas.

There is no one diet that is suitable for all people. While some people respond well to a macrobiotic diet, others need to have meat in their diet to feel well. Some people find that they feel better with a diet high in proteins and essential fatty acids and less carbohydrates. Others feel better with a diet that has less protein and more complex carbohydrates. Trial and error will help determine the best diet for the patient.

Nutritional Deficiencies

There is rarely one single deficiency or excess present in the population at large, since nutrients operate in relation to each other. For example, an excess of calcium can cause a copper deficiency. Excess copper can cause a zinc or iron deficiency. Serum levels of nutrients can be misleading because they do not always reflect the total body stores of the nutrients, but merely the amount necessary for homeostasis. Calcium, for example, will almost always appear to be normal in the serum, even if the patient has osteoporosis or other evidence of calcium deficiency. Another example is the serum magnesium. It only represents a small fraction of the total body stores and has little value in determining nutritional status.

Minerals regulate hormone activity and enzymes that affect all aspects of body functioning, from digestion to immune protection. The best assay for minerals are the blood tests done on the red blood cells, not the serum. When ordering from a standard lab, it is important to specifically request, for example, RBC magnesium or RBC copper.

Vitamins function as coenzymes in chemical reactions that take place in our bodies. Vitamin deficiencies can be tested by functional intracellular analysis. This test uses the patient's lymphocytes. The lymphocytes are observed for how well they grow after specific vitamins are added or removed from the external growth media. (SpectraCell Labs)

Antioxidants are nutrients that protect the cells from bacteria, viruses, and free radical damage. Many nutrients such vitamins C and E, beta carotene, selenium, glutathione, and coenzyme Q10 function as antioxidants. Several labs offer antioxidant testing.

Amino Acids, the building blocks of proteins,are indispensable nutrients. They play a crucial role in the prevention of depression by affecting the formation of inhibitory and excitatory neurotransmitters. Even when protein intake is adequate, amino acid levels can be low or out of balance due to abnormal digestive function. Testing can be done by certain specialty labs. (Doctor's Data)

Essential Fatty Acids are crucial for the function of the nervous system and for prevention of depression. These oils form the lipid layer in the outer membrane of all cells. They fall into two categories, omega-3 and omega-6. Fatty acid levels can be measured through blood testing. (Great Smokies Diagnostic Lab) Without adequate breakdown of molecules and assimilation of nutrients, even the best diet is insufficient and may lead to a variety of chronic disorders. The Great Smokies Comprehensive Digestive Stool Analysis includes testing for maldigestion and malabsorption.

Mold

Mold can be found wherever moisture accumulates. Check the walls for plaster that has bubbled. Look for stains and water lines on walls, ceilings, under window sills, and around skylights and chimneys, indicating possible mold contamination. Look carefully for leaks in the plumbing. Vaporizors can increase the growth of mold. Even when molds are contained inside walls or other building cavities, such as attics or crawl spaces, the slightest air current can send fungal spores and gases swirling through the air where they can be easily inhaled.

Mold plates can be ordered and placed in the areas in question. All places where there have been water leaks or elevated moisture should be tested. The mold plates can then be sent to a mycologist for identification of the colonies growing on the plates. For mold clean-up, borax, zephiran, and dilute bleach have all been used successfully. It is best to avoid the more toxic fungicides. If the infestation is extensive, such as in the drywall, it is best to cut out and replace the infested area after all leaks have been repaired. Remediation of the mold might require the help of a company specializing in environmental clean up.

Heavy Metals

Testing for heavy metal exposure can be done with hair, blood, and urine samples. The hair analysis can be used as a screening tool to assess past exposures. It is often used in conjunction with other tests, such as serum or red blood cell analysis for minerals and metals. Pre- and post-challenge testing using a chelating agent followed by 24 hour urine collection is used to assess body burden of heavy metals.

Hormones

Hormonal testing is an important part of a comprehensive evaluation for depression. The tests include the following:

• Glucose/Insulin Tolerance Test assays blood over a 4-hour period for levels of glucose and insulin, following a glucose challenge. Glucose and insulin should be tested simultaneously.
• Male and Female hormones can be tested using blood, saliva, or urine. A growing number of practitioners prefer using saliva testing. (Diagnos-Tech Lab or Aeron Life Cycle)
• Melatonin Profile analyzes 3 saliva samples for the secretion pattern of melatonin. (Great Smokies Diagnostic Lab)
• Adrenocortex Stress Profile assays 4 saliva samples over a 24-hour period for levels of cortisol and DHEA. (Great Smokies Diagnostic Lab)
• Thyroid Hormone testing should include free T4, free T3 and TSH. If these tests are negative, but there is a suspicion of thyroid disease, consider testing for anti-thyroid anti-bodies. Taking basal body temperatures is useful when hypothyroidism is suspected but blood tests are negative. Occult Infections

A common source of undiagnosed infections is the GI tract which can harbor a multitude of pathogens such as bacteria, fungus, and parasites. Standard stool testing often misses these pathogens. Two tests that are helpful are the Comprehensive Digestive Stool Analysis from the Great Smokies Lab and parasite testing from the Parasitology Testing Center, Inc. (see resources)

Treatments

Treatment of environmentally related depression needs to be individualized and based upon the findings in the history, physical exam, and laboratory testing. Examples of effective treatments include the following:

• avoidance or reduction of exposure to allergens and toxins
• dry sauna to reduce body burden of toxins bound to fat cells
• chelation for removal of heavy metals
• amalgam removal by a dentist experienced in mercury removal
• water and air filtration
• dietary manipulation such as avoidance of allergic foods and/or rotating diet, eating organic foods, and avoiding refined foods and hydrogenated oils
• nutritional support with vitamins, minerals, amino acids, and anti-oxidants, either oral or intravenous if indicated
• hormonal regulation (especially adrenal, thyroid, and sex hormones)
• avoidance of antibiotic and other drugs when possible; treatment by other methods like homeopathy, herbs, and acupuncture preferred
• identification and treatment of hidden infections, especially in the GI tract, of fungus, bacteria, and parasites
• digestive enzymes
• beneficial intestinal organisms
• daily aerobic exercise to facilitate detoxification and production of endorphins
• meditation and/or yoga
• desensitization treatments
• counseling to help cope with the symptoms

There are dozens of different environmentally related treatment options for treating depression, but note that not all options may be available in the location where the patient resides.

Special Populations - The effects of neurotoxicity are found in greater percentages among certain groups of people. These include 1) industrial workers, 2) occupants of "tight buildings", including office workers and school children, 3) residents of communities whose air or water is contaminated by chemicals, and 4) individuals who have had increased exposures to various chemicals in indoor air from pesticides, drugs, and consumer products. While these groups of people are at higher risk than the average person of suffering from an environmentally triggered depression, all of us are at risk to some degree in our lifetime.

Practitioners - There is a growing number of health care providers, such as physicians trained in environmental medicine, who have the training and interest in evaluating depression from this broader and more comprehensive perspective. The patient can inquire about the approach the health care provider takes in evaluating depression before pursuing treatment.