Part 2: Toxicity—Organ Toxicity

One way that toxicity can be measured is by its specific effect on an organ or organs. The kidneys and liver are most commonly associated with toxicity because of their primary roles in metabolism, detoxification, and excretion. However, all body organs can be affected including the skin, brain, heart, lungs, and gastrointestinal organs.

The liver is the metabolic powerhouse of the body and is responsible for processing fats, proteins, carbohydrates, and other nutrients into forms that are easier to use by the rest of the body. The liver also plays a key role in clearing the blood of drugs and other substances that can be potentially harmful. After metabolism, metabolites of the liver’s work are sent into the blood where they are filtered by the kidneys for excretion. The kidneys are highly effective filtration organs each composed of approximately one million nephron cells that filter on average 150–180 liters of plasma per day. Anything filtered out of the blood by the kidneys is then excreted in the form of urine. Under normal circumstances, both the liver and the kidneys work together very effectively to maintain the physiologic conditions needed for optional functioning. However, under toxicity conditions, even the most effective organs can become overwhelmed. Hepatic or nephron cells may become damaged in the presence of high level of a substance. If too many cells become damaged, the organ as a whole fails to function properly. Symptoms of liver damage or failure include: jaundiced skin or eyes, abdominal pain, discolored or bloody waste secretions, tiredness, nausea, and anorexia. Symptoms of kidney damage or failure include hypertension, edema, fatigue, nausea, anorexia, changes in urine output, mental changes, chest pain, and shortness of breath.

The brain is the body’s most vital organ and has many extra layers of protection to prevent damaging its fragile cells. One of the major tools used to protect the brain is the blood brain barrier. This “barrier” is composed of nearly 400 miles of tiny blood vessels called capillaries that have a much more selective permeability than capillaries found elsewhere in the body. This protects the brain from harmful toxins or from fluctuations in levels of vital molecules (hormones, electrolytes, etc.). Essential oils are lipid soluble, so they are able to easily cross the blood brain barrier. At appropriate levels, essential oils have been shown to induce many beneficial effects including calming the nervous system and promoting relaxation.* At toxic levels, essential oils, like anything consumed at inappropriate levels, can damage brain cells. Common signs of brain toxicity include headache, memory loss, dizziness, nausea, lightheadedness, personality changes, seizure, inability to speak or swallow, loss of consciousness, and coma.