VDH recommends that medical providers discuss the possibility of mercury exposure with patients who may be using non-prescription skin
lightening creams. Patients reporting the use of mercury containing
products should be evaluated for symptoms consistent with mercury
exposure. Please encourage your patients to refrain from using imported
products if there are no ingredients on the label, or if a product lists
mercury as an ingredient. Individuals should not use any cosmetic or
cream that lists any of the following on the label: “mercury,“
“mercurio,” “calomel,” or mercury compounds such as “mercurous
chloride.”
All three chemical forms of mercury (inorganic, organic or methyl, and elemental) have toxic properties. Inorganic mercury is used in a
number of homemade products, ranging from teething powders to skin
lightening creams. In the past it was used in antiseptics, laxatives,
and diuretics, but its use has since been banned in the United States.
Some of these products are still available in the international
marketplace.
The clinical effects of mercury toxicity can become manifest in a variety of ways, depending on the route of exposure, the duration and
intensity of the exposure, and the chemical form itself. Human case
studies and animal studies suggest effects of chronic exposure to
inorganic mercury may include skin sensitization, hypertension,
increased heart rate, sensitivity to light, fatigue, gastrointestinal
symptoms, and neurologic symptoms such as tremor, irritability, memory
loss, and difficulty thinking. Chronic exposure to inorganic mercury may
cause renal toxicity.
Young children and developing fetuses are more sensitive to the adverse effects of mercury. Children may become exposed when they are
touched by family members who use homemade face creams. Also, family
members may spread mercury to the food they handle and feed to children.
Mercury passes from mother to fetus through the placenta and from the
circulating blood stream into the brain. It can also pass to a nursing
infant through breast milk. Fetuses may have higher levels of mercury in
their blood than their mothers; exposing the fetus to high levels of
mercury may lead to developmental problems as a child. In children,
prolonged exposure to inorganic mercury may cause redness of the palms,
irritability, and loss of appetite. Children poisoned by mercury may
also develop neurologic, gastrointestinal, and renal problems.
Tests are available that measure the amount of mercury in blood, urine, breast milk, and hair. Twenty-four hour urine sampling is the
preferred testing standard for detecting inorganic mercury, however,
spot urine and/or blood sample may also used to screen for exposure.
Most clinical laboratories have the technology to test for mercury.
Because the elimination half-life of mercury is 30-60 days, a urine test
may be able to detect a past exposure. According to the CDC case
definition, a biologic confirmed case is one in which elevated urinary
or whole blood mercury levels (> 10 micrograms/liter) exist.
