Heavy Metal Accumulation in Sri Lanka

How Lead, Mercury, Cadmium contaminate your body ?


Chamali Liyanage

The outbreak of heavy metal pollution is not new to the world. Mercury pollution in Minamata Bay and Cadmium pol­lution in Toyama Prefecture in Ja­pan are among the popular inci­dents which led to several deaths and long term neurological symp­toms. In the Sri Lankan situation, the accumulation and contami­nation of heavy metals is not very much considered, addressed or studied.

Trace metals, whose densities are greater than 5 g/cm3, are simply considered as heavy metals. These metals enter the environment through natural processes and also exces­sively due to human activities. The production of toxins is caused by forming complexes/’ligands’ with organic compounds. Modified biological molecules cannot function prop­erly and results in malfunctioning of affected cells. Oxygen, Sulphur and Nitrogen are the common groups of ‘ligand’ formations and when metals bind to these groups, they inac­tivate important enzyme systems.

The conditions that lead to accumulation and spread of toxic heavy metals are extensive in the country. Massive garbage dumps and discharging of industrial waste water and domestic waste to water bodies are the most common situations. As the Sri Lankan garbage is just collected and dumped without sorting, metals coming from industries, houses and various other sources are accumulated. In this phenomenon, garbage dumped areas can be considered as rich sinks of heavy metals. Bloemendhal, exceeding 80 feet, 700 tons of garbage per day is a future catastrophe.

Studies done in Navinna area by Dr. Padmalal of the University of Sri Jayawardenapura re­vealed that the Lead, Cadmium, Chromium and Mercury levels in well water is greater than the standard values for drinking water. Even the vegetables grown around this area contain these metals. The issue is hidden and has not raised its head completely!
Fortunately no heavy metal poisoning has been recorded in Sri Lanka up to now. But there is a danger. One prediction is from Mer­cury, which is highly hazardous and slight ex­posure can affect human health. Normal soil levels of Mercury are between 0.0005 and 1 ppm and marine and freshwater phytoplank­ton are very sensitive and 0.001ppm can re­duce the photosynthetic efficiency. Animals, plants and many algae tend to absorb and accumulate Mercury.

Neither Mercury isolation, safe disposing nor similar mechanism is operated and a signifi­cant amount of Mercury can accumulate in the country. These amounts may be further enhanced with the promotion of new appli­ances to a larger extent such as CFL’s for en­ergy conserving. No doubt that it is a positive step towards conserving of energy but with­out having a proper recycling or recovering facility, the said benefit will not be gainful.
Among all the heavy metal poisonings, Lead is one of the most common. This can be seen affecting children who are in develop­ing stages, mainly via soil and paints. Lead is included in paints for drying, durability and moisture resistance. Most popular brands of paint manufactured in Sri Lanka exceed the standard limits of Lead in both enamel and emulsion paints. In the enamel category, Lead content is more than 200 times higher than the permitted level of Sri Lanka Standards Institution. Although the SLSI gives the stan­dards, they do not have the facilities to check the Lead contents in paints. Although Lead poisoning is not fatal, certain severe impacts can occur, specially in children
When we address the controlling of heavy metals, waste management comes to the top. Unless there is a proper management of waste, specially the urbanized waste, head­ing towards the prevention from heavy metal poisoning is nothing. As this is a wide rang­ing procedure, waste reduction, reusing and segregation, even in households have to be promoted.

Awareness is one of the most important posi­tive steps when controlling heavy metal pol­lution as we have identified that most people are unaware of safe handling techniques of these instruments. Industries, where general public is working in risky areas, have to be aware of the proper and better precautions to minimize the adverse impacts.

It is a foregone conclusion that heavy metals play an essential part in the manufacturing process. Therefore long term mechanisms have to be implemented by participating government authorities, manufacturers, deal­ers and consumers for sustainable handling of toxic metals.

Although the issue is yet in the preliminary stage it will be converted to a crucial stage. Therefore each of us, including decision mak­ers and the general public, have a unique re­sponsibility to perform their maximum con­tribution to mitigate the future disasters.

Chamali Liyanage an Environmental Officer of the Centre for Environmental Justice.