Little is known about lead poisoning

This is the title of a text message that one of my readers sent to me not too long ago and in that short message, she wanted more information about lead poisoning as well as its implication to health. She also observed that the media are reporting about the lead poisoning being experienced in Zamfara and Niger States but yet little is known about its hazards and why the public should bother about it. I totally agree and apart from her , I got relevant questions from many people face to face which I had to explain as there’s little information in the public domain about lead poisoning’s health and environmental hazard.

According to the World Health Organization, lead is a naturally occurring toxic metal found in the earth’s crust. Its widespread use has resulted in extensive environmental contamination, human exposure and significant public health problems in many parts of the world.

Important sources of environmental contamination include mining, smelting, manufacturing and recycling activities, and, in some countries, the continued use of leaded paint and leaded gasoline. More than three quarters of global lead consumption is for the manufacture of lead-acid batteries for motor vehicles. Lead is, however, also used in many other products, for example pigments, paints, solder, stained glass, crystal vessels, ammunition, ceramic glazes, jewellery, toys and in some cosmetics and traditional medicines. Drinking water delivered through lead pipes or pipes joined with lead solder may contain lead. Much of the lead in global commerce is now obtained from recycling.

Lead poisoning is entirely preventable, yet lead exposure is estimated to account for 0.6% of the global burden of disease, with the highest burden in developing regions. Childhood lead exposure is estimated to contribute to about 600 000 new cases of children with intellectual disabilities every year. Some simple fact about lead poisoning; 1. Lead is a cumulative toxicant that affects multiple body systems and is particularly harmful to young children.

2. Childhood lead exposure is estimated to contribute to about 600 000 new cases of children developing intellectual disabilities every year.

3. Lead exposure is estimated to account for 143 000 deaths per year with the highest burden in developing regions.

4. Lead in the body is distributed to the brain, liver, kidney and bones. It is stored in the teeth and bones, where it accumulates over time. Human exposure is usually assessed through the measurement of lead in blood.

5. There is no known level of lead exposure that is considered safe. 6. Lead poisoning is entirely preventable. It is highlighted that young children are particularly vulnerable to the toxic effects of lead and can suffer profound and permanent adverse health effects, particularly affecting the development of the brain and nervous system. Lead also causes long-term harm in adults, including increased risk of high blood pressure and kidney damage. Exposure of pregnant women to high levels of lead can cause miscarriage, stillbirth, premature birth and low birth weight, as well as minor malformations. Some sources and routes of exposure; 1. People can become exposed to lead through occupational and environmental sources. This mainly results from:Inhalation of lead particles generated by burning materials containing lead, e.g. during smelting, informal recycling, stripping leaded paint and using leaded gasoline; and ingestion of leadcontaminated dust, water (from lead pipes), food (from lead-glazed or lead-soldered containers).

2. Young children are particularly vulnerable because they absorb 4–5 times as much ingested lead as adults from a given source. Moreover, children’s innate curiosity and their age-appropriate hand-to-mouth behaviour result in their mouthing and swallowing lead-containing or lead-coated objects, such as contaminated soil or dust and flakes of decaying lead-containing paint. This route of exposure is magnified in children with pica (persistent and compulsive cravings to eat non-food items), who may, for example pick away at, and eat, leaded paint from walls, door frames and furniture.

3. Once lead enters the body, it is distributed to organs such as the brain, kidneys, liver and bones. The body stores lead in the teeth and bones where it accumulates over time. Lead stored in bone may be remobilized into the blood during pregnancy, thus exposing the fetus. Undernourished children are more susceptible to lead because their bodies absorb more lead if other nutrients, such as calcium, are lacking. Children at highest risk are the very young (including the developing fetus) and the impoverished.

What are the health effects of lead poisoning on children?

Lead has had serious consequences on the health of children. At high levels of exposure, lead attacks the brain and central nervous system to cause coma, convulsions and even death.

Children who survive severe lead poisoning may be left with mental retardation and behavioural disruption. At lower levels of exposure that cause no obvious symptoms, and that previously were considered safe, lead is now known to produce a spectrum of injury across multiple body systems.

In particular lead affects children’s brain development resulting in reduced intelligence quotient (IQ), behavioural changes such as shortening of attention span and increased anti-social behaviour, and reduced educational attainment. Lead exposure also causes anaemia, hypertension, renal impairment, immunotoxicity and toxicity to the reproductive organs. The neurological and behavioural effects of lead are believed to be irreversible.

In conclusion, these are simple information that we should continue to amplify in many fora and platforms to improve preventing lead poisoning in our midst.

All comments to Dr Aminu Magashi, Publisher Health Reporters. (healthweekly@ yahoo.com)