Lead (Pb) is a very important
industrial metal, which is used in almost every industry. It's uses can be
observed in insulation electronic coatings, storage batteries, lead-pipes, for
stabilization of certain plastics, in solder industry, ammunition, paints and
dyes, as well as in pewter. It's anti-corrosion , poor-conducting and easy to
handle properties made it the earliest metal used since Roman times.
Even though lead based-paints and leaded gasoline were phased out, the lead
contamination, usage and exposures, in our daily environment is still on-going.
We are exposed to some concentrations of lead everyday!
We know that lead, is toxic, yet we cannot avoid it. But what makes it so toxic
for human beings?
To understand the answer , it is sensitive to the explanation of the mechanism
od how lead reacts with our body at cellular levels:
-Lead preferentially replaces other metals (e.g., zinc, calcium and iron) in
biochemical reactions.
-Lead interferes with the proteins that cause certain genes to turn on and off
by displacing other metals in the molecules. This changes the shape of the
protein molecule such that it can't perform its function.
Research to identify which molecules binds with lead is still on-going. Some of
the proteins that are known to be affected by lead regulate blood pressure
(which can cause development delays in children and high blood pressure in
adults), heme production (which can lead to anemia), and sperm production
(possibly implicating lead in infertility). It can cause everything from
constipation to permanent reduction in your IQ and mental capacity.
Nevertheless, we assume that lead-poisoning makes you loose memory. This is
because lead displaces calcium in the reactions that transmit electrical
impulses in the brain, which may diminish your ability to recall information, or
make you stupid.
At times, lead-poisoning can also alter an individual's personality. People tend
to suffer from erratic mood-swings and fatigue and become more irritable.
Chronic lead poisoning can cause stunted growth (in children); miscarriages; and
a whole slew of other terrifying symptoms. The main concern is lead exposure
with small children because lead can cause developmental problems, plus kids
engage in activities that increase their exposure to the metal (e.g., putting
things in their mouths, not washing their hands as Dust/ Soil can be
contaminated with lead, Drinking water may be lead contaminated etc).
There are 2 major types of toxic exposures , which lead to toxicity:
-Acute lead poisoning; which is somewhat rare, occurs when a relatively large
amount of lead is taken into the body over a short period of time. It's effects
have been known since a long time.
-Chronic lead poisoning — a common problem in children — occurs when small
amounts of lead are taken in over a longer period.
Unlike some concentration based toxic compounds, lead is simply poisonous.
Paracelsus' idea that the dose makes the poison does not apply with lead.
There are government regulations regarding 'acceptable' limits for products and
pollution because lead is useful and necessary, but the reality is, any lead is
too much lead.
Iron, on the other hand, is a key nutrient. It is a trace element, and a part of
the oxygen- bearing component of red blood cells (haemoglobin). Lead prevents
the formation of haemoglobin and this results in causing lead-induced anaemia (hypochromic
anaemia). This can also be caused of iron-deficiency even if no lead is present.
Iron competes with lead for absorption in the gut and uptake within the body,
and vitamin C can enhance its ability to displace lead. Iron can aid in reducing
lead induced apoptosis (cellular suicide) within the brain, and can aid in
proper organ-functioning.
Iron deficiency is one of the most common deficiencies known. It occurs
generally in premenopausal to pregnant females, and small children and
particularly infants are more prone to be deficient in iron concentrations.
A well-balanced and healthy diet is advised by doctors, daily consumption of
vegetables and milk, and iron-supplements/ syrups for small children (If
required) are also prescribed by doctors to regulate iron concentrations in the
body, as these will reduce the lead levels to an extent.
Always remember, you need balance in order to sustain every system. Too much
iron, can also be toxic, but that is another aspect. You need iron in order to
transport oxygen in your red-blood cells.Your body is a closed system, so supply
it with the essentials to a well-balanced extent; too much good, is also bad.