‘Lead contamination in schools’ playgrounds can cause learning disabilities, behavioural challenges in children’

A Professor of Nuclear Analytical Geo-Chemistry at the Ajayi Crowther University, Oyeyemi Oshin, has warned that high concentration of lead contamination on schools’ playgrounds can affect children’s blood, which can cause learning disabilities, behavioral problems, anemia and even deaths.
Speaking as a guest lecturer at the 6th inaugural lecture of the university, Professor Oshin said it is a known fact that children are daily exposed to metal concentrations from play ground equipment and playground dust ingested via the hand-to-mouth pathway.
‘’Lead is one of the naturally occurring elements in our environment,
usually found in combination with other elements to form different
minerals. Lead is also toxic to all humans, and when exposed to high
concentration, an individual may get lead poisoning and eventually
die.’’
Oshin explained that one pathway by which individuals can be exposed
to abnormally high concentration of lead is through Lead Acid Battery
Recycling.
‘’This is the act of processing used or scrap lead-acid batteries for
the recovery of lead. The recycling process starts by removing the
combustible materials, such as plastics, and insulators by manual
sorting or burning. The metal alloy containing lead and other elements
like antimony  can then be smelted.  Alternatively, the lead in the
battery can be processed as a whole through heating in a special
furnace with the metals recovered at the end of the process’’.
The expert hinted that whatever the method used, gases from the
burning of the battery contains particles of lead and other
pollutants.
‘’When done in a controlled and organized manner, the combustion gases
are sent to a scrubber where the pollutants are neutralized and
removed. However, when the recycling is done in a crude manner, the
combustion gases are spewed into the environment through a chimney
thereby creating a potential threat to the humans around the
processing plant.
Oshin, who is also Head of the Department of  Earth Sciences, Ajayi
Crowther University,  further cautioned  that  Oyo town may be prone
to many of the problems that impact on human lives and health.
This, according to him, may be due to the impacts of indiscriminate
discharge of cassava juice on soil and groundwater.
Cassava is perennial root crop that is consumed in Nigeria in various
forms, including cassava flour [garri].
Oshin explained that that in Oyo township alone, there are over thirty
garri processing centres, adding that cassava is known to contain
small quantities of cyanogenic glycosides, especially hydroxycyanic
acid.
‘’Cyanide compounds are toxic to humans. Up to ninety-percent of the
total cyanogens in cassava may however be removed in the fermentation
fluid [cassava juice] produced during  the processing of cassava to
garri .The  cassava juice is potentially toxic to the environment , if
carelessly discharged during the dewatering stage of the cassava
processing.’’
He submitted that research results of the systematic  geochemical
mapping conducted in Oyo town and its environs revealed that soil in
the immediate vicinity of the cassava processing sites have relatively
high concentrations of total cyanide .
‘’This suggests that cyanide is rapidly attenuated  by the soil, and
unless the discharged cassava juice is allowed to navigate into a
receptacle , the cyanide in it is quickly absorbed by the soil.
However, the presence of significant amount of cyanide in well water
around the processing  sites shows that some cyanide is also leached
into the groundwater that feeds the well water.