Lead

Latest Edit: Iva Lloyd, ND 2014-02-17 (EDT)

Lead is a biologically toxic element found in large amounts in the environment due to human activity. Lead poisoning is one of the most common environmentally acquired diseases. The adverse effects of lead poisoning include altered mental function, cardiovascular disease and other cognitive conditions.

Background

Article	Lead Toxicity Causes and Effects, Vital Link; 2012 Spring

Article	The Impact of Food Intolerances and Lead on Cognitive Function, 2012 Spring;Vol19(1) Vital Link

• Lead has been used for thousands of years by many civilizations. There is evidence of lead in skeletons of the ancient Egyptians, of lead mines in ancient Turkey, and lead plumbing in ancient Rome.
• Historically lead has been used in cooking utensils, as a wine additive, in plumbing, as a fuel additive, and in paint.
• It is only in the last century that steps to reduce lead exposure have been taken, and now there is significant legislation restricting lead in commercial and industrial use in North America.
• In the developing world lead exposure remains a serious public health issue. There is an estimated 250 million people worldwide with blood levels of lead concerned toxic, with over 90% of these individuals living in developing countries.

Associated Conditions

Conditions associated with lead toxicity include:, ,

• Hypertension
• Female Infertility
• Male Infertility
• Spontaneous Abortion
• Gouty Arthritis
• Memory Loss
• Delayed Physical Development in Children
• Cognitive Impairment
• Hyperactivity Disorders
• Hypochromic microcytic anemia
• Autism, ADD, mental retardation, and cerebral palsy have been linked to environmental toxins such as lead, arsenic, toluene, PCBs and methylmercury.

Symptoms

Common symptoms of acute lead poisoning include:

• Encephalopathy
• Gastrointestional upset
• Kidney Failure
• Fatigue
• Irritability
• Poor Memory
• Vomiting
• Constipation
• Decreased Libido
• Seizure
• Coma
• Peripheral Neuropathy

Sources

• Food and Water

• Lead can enter food through contaminated soil, cooking wear or utensils containing lead, and through cans containing lead. Although canning processes using lead are banned in North America, lead can still be found in cans from other areas of the world.

• Industry:

• Occupational exposure is a common source of lead poisoning. Auto repair, smelting, construction, gun/bullet exposure, plumbing, and painting are all associated with elevated lead exposure.
• Lead used in the production of batteries, ammunition, pipes, ceramic products, caulking, and pipe solder can contaminate the surrounding environment.

• Cosmetics

• Lead based cosmetics still exist and are available in some countries.

• Environment

• Lead can be found in soil contaminated from exterior paint or past deposition of car exhaust.
• Children are at increased risk of lead exposure in the environment from putting objects and dirt in their mouths.

• Prenatal

• Lead readily crosses the placenta leading to elevated levels of lead in unborn children.

• Illicit Drugs

• The manufacture of “moonshine” often involves equipment containing lead.
• Production of methamphetamine may involve lead acetate and has been implicated in some cases of lead poisoning.

Diagnostic Testing

Article	"No Lead is God Lead" - Towards a lower threshold for the diagnosis of lead poisoning, Vital Link; 2012 Spring

• Urinary Testing

• Urinalysis to determine kidney function is necessary when evaluating the effects of lead toxicity.

• Blood Chemistry

• Blood levels are used to measure acute lead exposure, but is a poor measure of total burden due to leads relatively short half life.
• Other blood tests including a complete blood count, urea nitrogen, and serum creatinine may be useful to measure the effects lead exposure has on the body.

• Imaging

• Imaging studies including abodominal radiographs may be used to evaluate lead ingestion.
• X-ray fluorescence procedures are currently being studied which allow the amount of lead in bone to be evaluated.

Treatment

The primary treatment of lead toxicity is to reduce exposure, whether it is occupational, recreational, or environmental.

• Supplements

• Oral EDTA can be used to chelate out heavy metals.

• Chelation Therapy

• Intravenous chelation therapy using demercaprol, BAL, or EDTA is effective in treating lead poisoning. These therapies are used with caution as they can chelate other important minerals and nutrients such as zinc.
• Oral chelation therapy with succimer and D-penicillamine is also effective in lead toxicity.