Heavy metal poisoning, lead poisoning, Mercury poisoning, treatment policies, causes, arsenic toxicity, aluminium toxicity,

3. What are heavy metals?
• Naturally occurring elements
having high atomic weight and
specific gravity more than 4.0 are
the heavy metals.

4. » Heavy metal poisoning refers to when
excessive exposure to heavy metals affect
the normal functions of body .
» Examples : lead, mercury, arsenic,
aluminium, chromium and cadmium.
» Sources may be diet, medications,
environmental pollutions , and even
occupations (due to chronic exposure to
industrial effluents ).
» Occupational exposure account for a vast
majority of heavy metal poisoning and so
workers working at industries of metal
works are more susceptible.

5. Why the heavy metals are
harmful?
» Heavy metals are dangerous because
they tend to bio accumulate .
» The main pathophysiology behind
their harmful affects is that the heavy
metals bind with the oxygen ,
nitrogen, and the sulfhydryl groups in
the proteins and so causing alteration
in the enzyme activity.

6. » The toxicity depends upon :
» Amount of the dose exposed,
» Whether the exposure was chronic
or acute,
» Age of the person,
» Route of exposure. Example :
elemental mercury.

8.  Lead is a cumulative poison.
 Lead has no physiological role in
biological systems .
 Lead is included in the class of
summer diseases.
 Normal levels :
In children : 10mg/dl
In Adults : 25mg/dl

9. Lead
Newspapers
Curcumin
Battery
Cigarette
Lead
pipes
Exhaust
of
vehicles
Paint

11. Absorption
GI tract Lungs skin

17. Diagnosis
» Diagnosis of lead poisoning is difficult.
» Laboratory analysis of BLL, CBC, and some times by
checking the concentration of lead in bones .
» CBC examination reveals the basophilic stippling of RBC
and symptoms associated with Iron deficiency anaemia.
» FEP level may be useful in demonstrating the degree of
biological abnormalities.

18. Treatment policies
• Chelation therapy : -
• Calcium dodecyl edatate (CaNa2 EDTA) is
a parental chelating agent but a care must
be taken during its administration that it is
never administered alone and
dimercaperol is administered first.

20. » Fatal dose: 1-2 grams.
» Mercury may be absorbed in
elemental, organic or inorganic
forms.

21. FORMS SOURCES MAJOR
ROUTE OF
ABSORPTION
Target
Organs
ELEMENTAL broken
thermometers,
mercury bulbs,
sphygmomanometer
,
barometer
Respiratory tract
Nervous
system,
Kidney And
GIT
ORGONIC Fungicide , seed
dressings and
methyl mercury in
fishes
Gastrointestinal ,
skin (minor)
INORGANIC Used in gold
extraction and
caustic soda
manufacturing ,
Rodenticides
Gastrointestinal ,
skin ,Respiratory
(minor)

22. Symptoms
Elemental
Oral lesions
,tremors ,
physiological
changes
Organic
Paraesthesia ,
spasticity , taking
and hearing
impairment
Inorganic
ACRODYNIA,
Neuropathy and
renal disorders

24. ACRODYNIA

26. Arsenic

27. Agricultural Medical Alloys Military
Glassworks
industry
Exposure to Arsenic

28. » Hemoglobinuria
» Diarrhoea (rice and water
stools)
» Garlic like breath
» Jaundice
» Encephalitis

29. » Diagnosis include the analysis of arsenic
contents in hair and nails.
» Laboratory analysis of urinary and whole
blood arsenic measurements.
» CBC: acute haemolytic anaemia
» Serum electrolyte levels is lowered including
calcium and magnesium and is seen in
patients with vomiting and diarrhoea

30. » Dimercaprol
» Succimer
» Dimerval
» These chelating agents may no be
useful in treating the toxicity but helps
in curing haemolysis.

31. Aluminium

32. Sources
Building
materials
Cosmetics
Insulating
material
Food
Packing
Antacids
Cooking
Vessels
Cheese

33. » Is an oestrogen mimicker and so leads
to hypothyroidism, endometriosis and
other health issues
» Alzheimer's
» Brittle bones
» Damage to CNS (parkinsonism)
» It impairs the glutathione production
which is the mist important detoxifying
substance

34. » Diagnosis is mainly based on
symptoms and also indicated
by serum aluminium levels and
also by DFO ( Deferrioxamine)

35. » The treatment is basically symptomatic
» Deferrioxamine is the only treatment for
aluminium toxicity.
» It causes an acute in the serum aluminium
levels by chelating aluminium levels .
» Vitamin C also acts chelating agent.

36. » Volcanic activity is natural sources of
cadmium poisoning, used as a colour
pigment, batteries and stabilizer.
» Acute exposure may cause flu like
symptoms and muscle ache, called
as ‘The cadmium blues’.
» Treatment is by chelation therapy
using calcium disodium EDTA or
through dimercaprol.

37. » Chromium compounds when inhaled, act as
respiratory tract irritants and cause pulmonary
sensitization.
» Chronic inhalation increases the risk of lung, nasal
and sinus cancer.
» No proven antidote available for treatment and so
treatment is by removal of patient from further
exposure and reliance on body’s rapid clearance of
metal and symptomatic treatment is given.

39. » Chelation therapy is a common treatment in
heavy metal poisoning, but different drugs
are used in the treatment of different metals
because their site of accumulation,
mechanism of action and metabolism are
different, though they are put under common
class of heavy metals.