Although no new cases have appeared in the Bay Area, public health officials have maintained a health alert about mercury poisoning most recently caused by imported face creams from Mexico with high levels of mercury.

The El Paso Times wrote in late September about  six mercury poisoning cases in El Paso connected to Crema Antiedad y Desmanchadora, a Mexican anti-aging cream.

Health officials there told the El Paso paper that the product is nearly identical to another cream, Crema Aguamary, which may be responsible for 44 cases of mercury poisoning in Texas.  The cream has not been approved for use in the United States. In fact, the Associated Press reported last weekend that Mexican health officials are recalling Aguamary cream and have closed a factory in northwestern Sinaloa state after the latest mercury poisoning cases.

The latest case of mercury poisoning  in San Francisco was reported in May 2011, according to Jim Soos, assistant director of policy and planning in the San Francisco Department of Public Health.

It was traced to a commercial face cream that had been reformulated by a pharmacy in Michoacan, Mexico, and discovered because the woman participated in a community study that included measurements of mercury levels. “The test was not performed because the woman was feeling ill,” spokesperson of the California Department of Public Health Norma Arceo wrote in an email.

One year earlier, in May 2010, several other cases of mercury poisoning were discovered in the Bay Area after a family participated in a community study, Arceo said.  The poisoning came from an unlabeled cream from Mexico used for lightening the skin, fading freckles and age spots, and treating acne.

Both were attributed to creams, but none of the cases were in the Mission District. A check on the shelves at Milagros de Mexico at 2400 Mission Street, La casa de la salud at 3203 24th Street and the little unnamed store at 3260 24th Street showed no creams listing mercury in their ingredients.

In fact, most of the beauty creams sold at these stores are produced in the United States. “They’re putting a lot of troubles at the borders for products made in Mexico,” employee Ada Almendarez said in La casa de la salud. She said she had not heard of  the problems with mercury poisoning.

The department said consumers should not purchase or use any unlabeled products or any products that have mercury.

The U.S. Food and Drug Administration allows only trace levels of mercury (less than 1 part per million) in face cream products. As “thimerosal,” mercury is allowed in products for the eyes –  up to 65 parts per million  – only if no other effective and safe preservative is available for use.

“It is not legal to sell creams containing higher levels of mercury,” Arceo from the health department said. The cream detected last May contained very high levels of mercury: 56,000 parts per million.

After the cases discovered in 2010, the department prepared a Health Alert for clinicians and educational materials, Arceo said. The department put out a revised alert in February that listed the symptoms, including nervousness and irritability, difficulty with concentration, headache, tremors, memory loss, depression, insomnia, weight loss and fatigue.

They recommend taking unused home made face creams to a household hazardous waste collection site. People who may have used creams containing mercury or who think they have symptoms caused by mercury should seek medical care, health officials said.

Since many health care practitioners are unfamiliar with the effects of mercury, victims should take copies of the health alert and outreach materials with them to show to clinicians, she said.

The problem, said Arceo, is that the symptoms are similar to those of other illnesses. Moreover, mercury levels in the body are not routinely measured, and most health care practitioners may not suspect mercury as a cause of illness and therefore fail to  order tests or ask about the use of creams that might contain mercury.

“Getting a true count of mercury toxicity would be complex and extremely resource intensive,” she said. “Obtaining accurate count would involve setting up a counting and reporting system that does not currently exist. Because mercury tests are not routinely performed by clinicians this would involve legislative mandate.”

The cases in the Bay Area were discovered just because the victims participated in community studies that included measurements of mercury levels. The creams were purchased in Mexico by relatives of the users and imported in personal luggage, Arceo said.

If undetected, mercury toxicity may result in more severe health effects than if the exposure source is detected and stopped early. However, “death is unlikely to occur due to mercury toxicity alone,” Arceo said.

Moreover, mercury in the blood of pregnant women crosses the placenta into the blood of unborn babies. “Children may be more likely to suffer from the effects of mercury,” she said. In addition to the health effects in adults, children may show muscle weakness and painful red discoloration of the hands and feet.