Several blood samples in test tubes contained in a wire rack.

Choosing the appropriate type of sample

Plasma

Plasma is the recommended sample type for Essential Panel testing (Chromium, Cobalt, Copper, Manganese, Molybdenum, Selenium, Vanadium, and Zinc) or individual essential trace elements to assess nutritional status. Plasma levels of essential trace elements changes more quickly than erythrocyte levels, thus plasma levels are better indicators of recent intake or deficiency.

Plasma Aluminum testing is routinely used for monitoring patients with renal failure on dialysis.

Erythrocytes

Erythrocytes is the recommended sample type for Essential Panel testing (Calcium, Chromium, Cobalt, Copper, Magnesium, Manganese, Molybdenum, Selenium, Vanadium, and Zinc) to monitor steady-state levels of the nutritional elements.

For patients with acute phase reactions, erythrocytes is the best sample of choice for Copper, Selenium, and Zinc assessment.

Erythrocytes can also be used to assess on-going or recent exposure to toxic elements, including Arsenic, Cadmium, Lead, Mercury and Thallium.

It is also the preferred sample of choice for assessment of long-term occupational exposure to Manganese.

Whole Blood

Whole blood is the sample to choose for Toxic Panel testing (Arsenic, Cadmium, Lead, Mercury, Nickel, and Thallium) or individual toxic elements.

It is also recommended for metal ion analysis to evaluate patients with metallic orthopedic implants such as Aluminum, Chromium, Cobalt, Molybdenum, Nickel, Niobium, Titanium, Vanadium, and Zirconium.

Urine

Urine is the preferred sample type for on-going occupational exposure. It can be used for monitoring recent exposure to toxic elements such as total and inorganic Arsenic, organic Lead, elemental Mercury and inorganic Mercury, but not useful for organic Mercury. Urine is not recommended for monitoring exposure to Manganese.

Urine is the preferred sample of choice for Iodine assessment.

24-hour urinary Copper is required to investigate Wilson’s disease.

Hair and Nails

Hair and nails can be used to assess long term exposure to heavy metals such as inorganic Arsenic and organic Mercury, not useful for elemental and inorganic Mercury.

Tissue

Liver Copper and Iron levels are commonly analyzed to investigate Wilson’s disease and Hemochromatosis.

Schulich School of Medicine and Dentistry London Health Sciences CentreSt. Joseph's Health Care LondonWestern University