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Letter to Doctors on Lead Poisoning

5 February 2001

Dear Doctors,

A case of lead poisoning was reported to the Department of Health recently. Investigation by this Department showed that the poisoning was due to ingestion of a herbal pill named "Bao ning dan" ( 保 寧 丹 ) home-made and prescribed by ONE  Traditional Chinese Medicine practitioner.

Because of lack of information, we are not able to trace all the people who have taken the pill before its distribution was stopped. Therefore, the Department has appealed to members of the public who have ever  taken this Bao Ning Dan to contact the Department for counselling, testing and management.

Should you encounter patients who have a history of ever  taking the herbal pill named "Bao ning dan"  supplied by this practitioner, please advise them to contact the Department of Health at the telephone hot-line number 2961 8883 for further management.

An information sheet on lead poisoning is enclosed for your reference.

In order to facilitate prompt investigation and control of heavy metal poisoning including lead, please report all heavy metal poisoning cases to the respective Regional Office of the Department of Health at the following telephone numbers:

Region Tel no.
Hong Kong 2961 8791
Kowloon 2199 9100
New Territories (East)      2684 5138
New Territories (West)      2615 8571

    Yours sincerely



  (Dr C K LI)
for Director of Health

Lead Poisoning - Information Sheet for Doctors

Lead and lead metabolism

Lead is a naturally occurring heavy metal, and usually presents in very small amount in the environment. Lead and its compounds may be found in products such as batteries, lead-based paints (on walls, toys etc), some vinly mini-blinds, lead-containing ceremics, lead pipes and lead solder in pipes, leaded petrol. In everyday life, lead does not pose a threat to health.

Lead enters the human body primarily by ingestion and inhalation (and organic lead via skin absorption). It is accumulated in soft tissues (kidney, bone marrow, liver and brain) and hard tissues (bones and teeth). Lead is excreted mainly in the urine and in the faeces. The half-life of lead is about 25 days in blood, about 40 days in soft tissues, and more than 25 years in non-labile portion of bone.

Clinical features of lead poisoning

When absorbed into the body in significant amount, lead is toxic to many organs and systems, including the central and peripheral nervous systems, gastrointestinal tract, kidneys, red blood cells, and cardiovacular and reproductive systems. Lead poisoning can present as follows :-

Adults Children
Abdominal pain
Fatigue
Anaemia
Heart failure
Depression
Gout
Kidney failure
High blood pressure
Wrist or foot weakness
Reproductive problems
Deficits in short term memory
Inability to concentrate
Lead line (a blue/black line at the gingival-tooth border)
Abdominal pain
Fatigue
Anaemia
Learning problems
Constipation
Vomiting
Diarrhoea
Decreased appetite
Sleeplessness
Lowered IQ
Lead line (a blue/black line at the gingival-tooth border)

Severe cases of lead poisoning can lead to acute encephalopathy. Signs and symptoms of lead encephalopathy include seizure, bizarre behaviours, ataxia, apathy, incoordination, vomiting and alteration in conscious state. Acute lead encephalopathy is a medical emergency, but it rarely occurs in adults.

Infants and children are particularly vulnerable to lead exposure since lead is more easily absorbed into growing bodies and the tissues of children are more sensitive to the damaging effects of lead. Elevated blood lead levels in children can also lead to learning disabilities, behavioural problems and mental retardation. In pregnant women, as lead readily crosses the placenta, fetuses are also at risk.

Management of patients with suspected lead poisoning

A blood test is available to measure the amount of lead in blood. The laboratory reference blood lead level is 0.2-0.7 micro mol/L for adults, and 0.2-0.47 micro mol/L for children. In pregnant women, the acceptable level of lead in blood is much lower. For patients with lead poisoning, further investigation & in-patient management may be required. Chelating therapy may be indicated in some cases.

The Department of Health has set up a service for counselling, screening and treatment for people who had taken to a herbal pill named "Bao ning dan"   (保 寧 丹) home-made and prescribed by ONE  Traditional Chinese Medical Practitioner. People who have ever  taken the pill in question should be advised to contact the Department at the telephone hotline 2961 8883.

Department of Health

February 2001

Fact Sheet
Lead Poisoning

Lead is a naturally occurring heavy metal, and usually presents in very small amount in the environment. Lead and its compounds may be found in products such as batteries, lead-based paints, lead-containing ceremics and leaded petrol. In everyday life, lead does not pose a threat to our health.

Health effects of lead

Lead can enter the human body by ingestion, inhalation and skin absorption. When lead is absorbed into the body in excessive amount, it is toxic to many organs and systems. It can affect the blood, nervous system, the gut, and kidneys; leading to anaemia, fatigue, joint and muscle pain, muscle weakness, poor memory, abdominal pain, vomiting and kidney damage.

Children are particularly vulnerable to lead exposure. Elevated blood lead in children can also result in learning disabilities, behavioural problems and mental retardation. In pregnant women, as lead readily crosses the placenta, fetuses are also at risk.

Lead Poisoning and "Bao ning dan"

There was a recent report of lead poisoning due to ingestion of an herbal pill named "Bao ning dan".  This was an isolated incident related to a herbal pill home-made and prescribed by ONE  particular Traditional Chinese Medicine practitioner. The distribution of the herbal pill in question has already been stopped.

The Department of Health has a surveillance system in place for detecting heavy metals in Chinese Medicine. In the past five years, more than 4,000 samples were tested, of which 99% were within acceptable limits for heavy metals. Those which failed the tests had been withdrawn from the market promptly.

If you suspect that you or your family members are suffering from lead poisoning, you can consult your family doctor.

If you have ever  taken the above-named "Bao ning dan",  please call the Department of Health hotline at 2961 8883 for counselling and assessment.

Department of Health
February 2001

  Last Revision Date : 18 Dec 2015