Measuring the Body Burden of Toxic Trace Metals in Humans
Dennis N. Crouse
Aluminum – Drinking water containing orthosilicic acid (OSA) has been proven to remove aluminum from most organs of the body including bone and brain. Therefore, the best way to measure your body burden of aluminum is to drink a liter of Fiji water or Silicade that contains 124ppm of OSA and then collect your urine for 24 hours. Measure the total volume of the collected urine and have total aluminum concentration (in units of nanomolar) and total creatinine (in units of micromolar) both quantified in the collected urine. The ratio of aluminum to creatin concentrations reflects the blood aluminum through-out the body over a 24-hour period. This is more representative of your aluminum body burden than a blood sample that is only representative of the time and place where the blood sample is taken. It is also more reliable than hair samples as some shampoo and hair colorants have aluminum as an ingredient.
Based upon the color of your urine you know that it is sometimes more dilute than at other times. This can be due to inhibition of diuretic hormone by substances, such as alcohol, that reduce the reabsorption of water from the urine resulting in dilute urine. Both aluminum and creatinine once in the kidney are not reabsorbed back into the blood, unlike water. Creatinine is a breakdown waste product from muscle and is present in a narrow concentration range in urine. Therefore, a ratio of aluminum to creatinine concentrations minimizes the effect of urine dilution.
For 10 healthy adults who had not consumed 1 liter of OSA rich water the mean of urinary aluminum (nM/mM creatinine) is 43 and silicon (mcM/mM creatinine) is 32. These numbers are dependent upon the health of an individual and amount of aluminum and silicon in their diet and drinking water. For instance, secondary progressive multiple sclerosis (SPMS) is a disease in which aluminum accumulates in the brain at levels higher than normal. Patients with SPMS who drank 1 to 1.5 liters per day of OSA rich water for twelve weeks had mean urinary aluminum levels of 135 (nM/mM creatinine) before drinking OSA rich water and 349 (nM/mM creatinine) after 12 weeks or drinking OSA rich water.
Lead – Exposure to lead can be measured with a whole blood test. However, the blood lead level (BLL) is not a reliable indicator of prior or cumulative dose or total body burden of lead. An indicator of prior lead exposure is a buildup of erythrocyte protoporphyrin in red blood cells. Tests are used to measure free erythrocyte protoporphyrin (FEP) and zinc protoporphyrin (ZPP) in the blood. When BLLs reach or exceed 25mcg/dL an increase in FEP and/or ZPP can be detected. These increases in FEP and ZPP usually lag increases in BLL by two to six weeks. When BLLs reach 40mcg/dL the FEP or ZPP levels increase abruptly and stay elevated for 3-4 months which is the average life span of a red blood cell.
· Elevated BLL and Normal FEP/ZPP = Recent exposure to lead in last 2-6 weeks
· Elevated BLL and Elevated FEP/ZPP = Chronic/ongoing exposure to lead
There is no safe level of lead and all adults have some body burden of lead. The U.S. National Institute for Occupational Health and Safety (NIOSH) in 2015 indicated 5mcg/dL as a reference BLL above which action should be taken to target the detox of lead.
Mercury – Mercury in the body can be in three chemical forms: organic mercury, such as methylmercury from eating fish, inorganic mercury, such as mercuric ion and mercury selenide, and metallic mercury, such as the mercury in dental fillings and some thermometers.
· Methylmercury is measured in a whole blood sample taken from a vein.
· Inorganic mercury and metallic mercury are measured in a random or 24-hour urine sample.
A hair sample can be measured to indicate exposure to increased levels of methyl mercury. However, hair samples are rarely used due to hair exposure to mercury containing dyes, bleach, and shampoo.
The Centers for Disease Control and Prevention (CDC) define the laboratory criteria for a diagnosis of excessive mercury exposure is blood mercury level greater than 10mcg/L. Most people have hair mercury levels well below 1mcg/gr (ppm). Adults with average hair mercury level of 4.2mcg/gr have neuropsychological function deficits. Maternal hair mercury levels of 0.3 to 1.2mcg/gr have been associated with prenatal neurodevelopmental effects. If you have levels over these limits, stop eating fish and begin augmenting your diet with L-selenomethionine.
Arsenic – Significant exposure to arsenic results in greater than 12nanograms/ml in blood taken 4 to 6 hours after exposure. Blood concentration of arsenic are elevated for only a short period of time after exposure. This is because arsenic has a high affinity for tissue proteins. The body treats arsenic like phosphate and incorporates it in place of phosphate. Arsenic is excreted at the same rate as phosphate with an excretion half-life of 12 days because most of ingested arsenic is in tissues, not in the blood where it has a half-life of 4 to 6 hours. Therefore, 24-hour total urine samples, not blood samples, are most useful for measuring the body burden of arsenic. The concentration of inorganic arsenic and its metabolites (i.e., MMA and DMA) in urine reflects the body burden of absorbed arsenic due to acute or chronic arsenic exposure.Hair analysis can only be used as a screening tool for arsenic intoxication as there can be arsenic deposition in hair due to hair exposure to arsenic containing dyes, bleach, and shampoo. Also, there are uncertainties about the normal levels of arsenic in hair.