"Published Occasionally at Irregular Intervals"
~ Dr.
Arthur L. Craigmill ~
Extension
Toxicologist
Third National Report on Human Exposure to Environmental Chemicals
~~ TOXICOLOGY TIDBITS ~~
ADA Updates Fluoridation Booklet
On November 10, school officials at a county high school in rural Kentucky discovered approximately 15 students playing with liquid mercury in the school cafeteria. School officials separated the students, confiscated and bagged their clothes, and closed the cafeteria. Local health department and environmental protection officials were notified. Questioning revealed that a boy aged 15 years had brought a vial of mercury to school on a school bus. Parents were advised to consult their health-care providers about whether their child should be tested for mercury exposure. Several children were tested at the local hospital, but none had concentrations exceeding background levels other than the student who brought the mercury to the school.
During November 10-24, local and state health department staff coordinated a public health investigation of the mercury exposure, and the U.S. Environmental Protection Agency (EPA) conducted an environmental investigation. Law enforcement and health department staff interviewed relevant observers and persons who directly handled the mercury. Serum and 24-hour urine mercury samples (measured in micrograms per liter [µg/L]) were collected for all persons who reported substantial exposure (i.e., persons who were known to have handled the mercury on multiple occasions or who spent 1 hour or more in rooms or vehicles during periods in which those places were known to be contaminated) and were tested at a local hospital. EPA and Kentucky Department for Environmental Protection (KDEP) personnel collected environmental air samples (measured in nanograms per cubic meter [ng/m3]) at implicated locations and conducted ongoing cleaning and environmental assessment until ambient mercury levels were brought within acceptable limits (i.e., <3,000 ng/m3) or the site was deemed unrecoverable.
EPA and KDEP officials assessed the student's school and home environments and initiated cleanup procedures. The school cafeteria contained mercury levels ranging from 5,280 ng/m3 to 36,600 ng/m3. The school was closed by the school superintendent to limit the potential for exposure of children and to facilitate cleaning of the cafeteria. After 2 days of cleanup, heating, and venting, EPA deemed the school safe for students to return.
Approximately 15 school buses were also tested
and/or cleaned. The
family's mobile home and possessions were deemed unrecoverable (ambient
mercury was >50,000 ng/m3 at outset of investigation and
later reduced to 11,550 ng/m3) and were removed and
destroyed. The family van (14,950 ng/m3 reduced to 1,285 ng/m3)
and an additional vehicle (>50,000 ng/m3 reduced to 174
ng/m3) were eventually cleaned and returned to the family.
However, a third vehicle (41,275 ng/m3 reduced to 36,610 ng/m3),
belonging to the family of a friend of the student, was determined
unrecoverable and removed by EPA.
During the cleanup process, more liquid mercury was collected than could be contained in the vial that the student had carried to school. The student claimed that he had found the mercury in the trash of a dentist's office during a visit on November 9. Investigation revealed that the mercury was kept in a storage area at the dentist's office that doubled as a restroom for patients. Examination of dental office records indicated that the student had visited the dentist on August 29, 1997, August 21, 2003, and November 9, 2004. Additional evidence suggested that the student had mercury for several months before the school exposure. Under further questioning, the student admitted having obtained the mercury during a previous visit to the dentist (presumably the August 2003 visit). Investigators suspected that the student took mercury during each of the last two visits, accounting for the excess mercury recovered in the cleanup process. EPA personnel disposed of all remaining mercury in the dentist's office.
Nine family members, including the student, had lived in the mobile home during different periods preceding the incident. In addition, the student's friend and his family, including a pregnant female, indicated that they had spent considerable time in one of the contaminated vehicles. Moreover, an additional 12 persons were said to have spent substantial amounts of time in the mobile home.
Blood concentrations were obtained for the
student and seven family
members who were living in the mobile home. Blood mercury levels ranged
from 32 µg/L to 72 µg/L (normal: 0-10 µg/L).
The 24-hour urine mercury
concentrations obtained from seven of these patients ranged from 28 µg/L
to 496 µg/L (normal: 0-19 µg/L).
The student had the highest mercury levels for both blood and urine
(i.e., 72 µg/L blood and 496 µg/L for
initial urine concentration). Urine mercury concentrations were
directly associated with amount of time spent in the mobile home. Three
of the children, including the student, lived in the contaminated home
for 15 months and had urinary concentrations ranging from 193 µg/L
to 496 µg/L, whereas three of the children who lived in
the home for only 10 weeks had urinary concentrations ranging from 28 µg/L
to 68 µg/L. The additional family member, a woman who had
not been in the mobile home since June 2004, had a urine mercury
concentration of 241 µg/L. Three additional persons, who
were exposed to the contaminated vehicle that had to be destroyed, had
urinary mercury levels ranging from 4 µg/L to 8 µg/L.
An infant born to one of these persons in May 2004 had no signs of
mercury exposure. Five family members, including the student
responsible for the initial exposure, were chelated by using succimer.
The three adolescent family members with the longest exposures received
chelation in multiple sessions. Final urine mercury levels were 48, 44,
and 35 µg/L, for the student and the two other children,
respectively.
Several of the children living in the mobile home experienced itchy rashes and headaches. In late 2003, one girl aged 13 years residing in the mobile home had experienced several months of illness consistent with mercury exposure (e.g., unexplained tachycardia, hypertension, desquamation of soles and palms, rashes, diaphoresis, muscle pain, insomnia, vomiting, and behavioral and psychiatric changes). She was hospitalized for approximately 30 days. Mercury toxicity was not considered at the time, so testing was not performed. The patient improved with a cardiac stent concurrent with removal from the exposure setting.
Editorial Note: Mercury spills and exposures are common. In EPA Region 4, a total of 40 documented mercury spills occurred during September 1, 1999-March 23, 2005, with 14 of those spills occurring in fiscal year 2005. Kentucky experienced 15 spills during that period, 10 of which were associated with schools and five with residences only.During this investigation, a strong association was observed between the duration of exposure and remaining levels of mercury in patients. Compared with three children who had recent exposures of 10 weeks' duration, a woman who had been exposed for 8-10 months but left that setting approximately 5 months before the November incident had substantially higher levels of mercury, as evidenced by high urine concentrations. Children exposed for 15 months in the mobile home had substantially higher levels than those who had only 10 weeks' exposure. Only those children who experienced the 15-month exposure were recommended for chelation. Finally, although the family acquaintances were exposed to high levels of mercury (i.e., in their contaminated vehicle), their exposures were periodic and brief, which might have resulted in limited mercury levels.
The mercury exposures described in this report, which occurred in multiple locations and resulted in extensive property loss and intensive cleanup efforts, highlight the utility of multiagency collaboration in investigations. Collaboration of local, state, private, and federal officials improved the response time and investigation outcome. This coordination is essential to mount a public health response to exposures such as this, which quickly outstrip local resources.
REF: MMWR, August 19, 2005 / 54(32);797-799
TOXICOLOGY TIDBITS
Smoking harms nearly every organ of the body, causing many diseases and reducing quality of life and life expectancy. This report assesses the health consequences and productivity losses attributable to smoking in the United States during 1997-2001. CDC calculated national estimates of annual smoking-attributable mortality (SAM), years of potential life lost (YPLL) for adults and infants, and productivity losses for adults. The findings indicated that, during 1997-2001, cigarette smoking and exposure to tobacco smoke resulted in approximately 438,000 premature deaths in the United States, 5.5 million YPLL, and $92 billion in productivity losses annually. Implementation of comprehensive tobacco-control programs as recommended by CDC can reduce smoking prevalence and related mortality and health-care costs.
REF: MMWR, July 1, 2005.
The FDA is warning consumers not to take Liqiang 4 Dietary Supplement Capsules because they contain glyburide, a drug that could have serious, life-threatening consequences for some people. Liqiang 4 has also been called Liqiang Xiao Ke Ling--Liqiang Thirst Quenching Efficacious--in ads in Chinese language publications. The ads promote the substance as being derived from only natural ingredients and as being useful for controlling diabetes.
Glyburide, a drug used to lower blood sugar, is safe and effective when used as labeled in FDA-approved medications. But people who have low blood sugar or those with diabetes can receive dangerously high amounts of glyburide by consuming Liqiang 4. Consumers should immediately stop using this product and seek medical attention, especially if they are being treated with diabetes drugs or if they have symptoms of fatigue, excessive hunger, profuse sweating, or numbness of the extremities. Consumers who have this product should dispose of it immediately.
The FDA learned of the potential problem through an anonymous consumer complaint, and followed up with testing that revealed the presence of glyburide in Liqiang 4. The product is sold as part of a shrink-wrapped two-bottle set. One of the 90-capsule bottles is labeled Liqiang 4 Dietary Supplement Capsules, and the other bottle is promoted as a "bonus pack" of Liqiang 1. The FDA is evaluating Liqiang 1 and other versions of this line of products to determine their composition and safety.
The product is manufactured by Liqiang Research Institute, China, and marketed throughout the United States in herbal stores and through mail order by Bugle International of Northridge, Calif.
The FDA encourages consumers, health
professionals, and caregivers to report adverse events related to this
product to MedWatch, the agency's voluntary reporting program. Phone:
(800) FDA-1088; Fax: (800) FDA-0178; Online: www.fda.gov/medwatch/report.htm;
or
Mail: MedWatch, FDA, 5600 Fishers Lane, Rockville, MD 20857-9787.
REF: FDA Consumer Magazine, September/October 2005
The FDA is reminding consumers about the risks of drinking juice and cider that has not been treated through pasteurization or other means to ensure its safety. When fruits and vegetables are made into juice, harmful bacteria which may be present on the produce can become part of the juice. Unless the juice is pasteurized or otherwise treated, the bacteria may cause serious and even fatal illness in consumers. Young children, the elderly and persons with weakened immune systems have the highest risk of contracting illness. Parents, school officials, and children's activity leaders need to be aware of this.
When purchasing juice in a store it is easy to tell if it has been treated for safety. Untreated packaged juice products are required to bear the following label: WARNING: This product has not been pasteurized and, therefore, may contain harmful bacteria that can cause serious illness in children, the elderly, and persons with weakened immune systems. However, not all juice comes from a retail store. School officials and others often take children to farms and orchards for fall activities. Untreated cider may be served by the glass at these activities. No warning signs or labels are required for juice served by the glass. Therefore, FDA recommends that, when you plan such activities, you ask if untreated juice or cider is served at the location, and if it is avoid giving it to children. Fruit and vegetable juices and cider are nutritious, healthful beverages as long as they are pasteurized or otherwise treated to kill harmful bacteria. By following these recommendations, fall activities can be safe as well as fun.REF: FDA Consumer Magazine, September/October 2005
If you think you're having a heart attack, you're supposed to take an aspirin right away. A dose of 325 milligrams will do. Aspirin keeps platelets from clumping. And that should help keep the blood clot (or clots) in your coronary arteries -- which is what triggers the heart attack -- from getting any bigger and further depriving your heart of the blood it needs.
Time is of the essence, and chewing the aspirin tablet will get the anti-sticky-platelet action going faster. Needless to say, you shouldn't take coated aspirin, which is designed to bypass the stomach and be absorbed in the intestine.
But the advice to "chew then swallow" only
applies in emergencies. A report published in 2004 in the Journal of the American Dental Association
described the consequences of routine aspirin chewing for two patients
with jaw problems (temporomandibular pain) and overly sensitive teeth.
They chewed four to eight aspirins a day for two years, seriously
damaging the enamel and dentin of their teeth. Obviously these were
extreme cases, but the lesson learned is that regularly chewing aspirin
is bad for your teeth.
REF: Harvard Health Letter, September 2005
