Among skin lightening cream users, absorption
of mercury likely occurred by applying the cream directly to the face and
inhaling mercury vapor generated by the skin lightening cream. Nonusers who had
elevated mercury levels likely came in contact with household items frequently
touched by cream users (1).
The infected individuals used the unlabeled
skin lightening creams with mercury content measured at 2.0% – 5.7% by weight
(1). The users report applying the cream intermittently to as frequently as two
times per day for as long as several months up to five years. The half-life of
inorganic mercury is 1-2 months (1). As a result, mercury levels increase
gradually due to repeated use of the skin cream.
Five households totaling twenty-two
individuals were exposed to an unlabeled skin lightening cream. Household one
received the skin cream from relatives in another state, and thus recommended
it to other locals in California. Exposed individuals all used skin to lighten
skin or to treat acne (1). Of the twenty-two exposed, fifteen individuals had
urinary mercury concentrations ?5 ?g/g creatinine (1).
Six of the skin cream users experienced nonspecific
symptoms such as numbness, tingling, dizziness, forgetfulness, headaches, and
depression (1). All of these symptoms
are consistent with chronic exposure to mercury.
In terms of toxic endpoints, no one in this
case report died by exposure to mercury from regular skin cream use. All
individuals with elevated urinary mercury concentrations were advised to seek
medical evaluation (1). Although only five were evaluated, all were diagnosed
with mercury poisoning.
The Environmental Protection Agency (EPA)
advised that the individuals infected should stop the use of the lightening
cream immediately and discard of all creams and other contaminated items and thoroughly
clean contaminated effected areas of the home (1). They were advised to have
repeat urine mercury concentration tests conducted to ensure mercury levels
continue to decrease.
Chronic exposure to inorganic mercury can
affect the kidney, producing oliguria, proteinuria, edema, and nephrotic
syndrome (1). Chronic exposure to mercury can also cause many neuropsychologic
effects including nervousness, irritability, decreased cognitive function,
tremor, insomnia, paresthesias, fasciculations, ataxia, and fatigue (1). In
exposed children, mercury can cause additional problems such as actodynia,
irritability, anorexia, and poor muscle tone (1).
To prevent further exposures in the five
households, the EPA revisited all households and tested the areas of the homes
that previously shown elevated mercury levels. The results indicated the
mercury contamination had either decreased or dissipated in all areas of the
homes (1). The California Department of Public Health (CDPH) and the Virginia
Department of Health (VDH) worked
together to issue Spanish and English alerts to the public in their respective
states to immediately stop the use of unlabeled skin lightening creams. CDPH
and VDH worked with the CDC to alert federal health authorities in Mexico of
the mercury exposure in the skin lightening creams manufactured in their
country (1). Furthermore, the CDPH notified the California Office of Binational
Border Health (1).
Similar case reports discuss elevated mercury
levels among those who use skin-lightening creams. For example, Mercury Poisoning Associated with Beauty
Cream – TX, NM, CA, 1995-1996 reported several
individuals who experienced mercury poisoning from using skin lightening cream (2). In contrast, Mercury Exposure Among Household Users and Nonusers of Skin-Lightening
Creams – CA, VA, 2010 was the first of its kind to report Mercury exposure in
nonusers who also resided in the household (1). Additionally, the
1995-1996 case report was able to
identify the cream to be “Crema de Belleza” (2). But the 2010 case report was unable to
identify the skin cream’s name due to unlabeled bottles.