Ota-piapia can damage liver, cause anaemia —Expert
As the dry season approaches with mosquitoes likely to be more rampant, a medical expert, Dr Olatunde Owoeye, has warned against the indiscriminate use of ota-piapia, a common locally made insecticide because its prolonged use can affect body organs and cause anaemia.
Dr Owoeye, a lecturer at the Department of Anatomy, University of Ibadan, said prolonged exposure to fumes of these insecticides can damage organs of the body such as the liver, kidney and the lungs.
Dichlorvos, traded under names as Nuvan, Sniper and Ota-piapia is used to control insects on crops, household and store products, and also to treat external parasitic infections in farms.
Spraying ota-piapia without good ventilation before going in to sleep, he said would expose humans to its inhalation and absorption through the skin and its accumulated negative consequences.
Dr Owoeye stated that studies in animals at the University of Ibadan over a seven-week period should that prolonged exposure to the insecticide in poorly ventilated rooms had negative effects on important organs of the body such as the lung, liver, brain and kidney.
He declared, “it is worthwhile to note that the effect of dichlorvos was more deleterious on the liver than the lung, despite the same duration of exposure.”
Dr Owoeye noted that prolonged exposure to the insecticide also breaks down red blood cells, thus predisposing to anaemia, added that it could also lower sperm count.
He stated, “when people burn mosquito coil or spray ota-piapia and then go to sleep inside such a room, they are inhaling the gaseous part of that dichlorvos, the insecticide that is to kill mosquitoes.
“So, when we use insecticides, we should always wait and allow a minimum of one hour to pass. If possible one can use a fan to blow away its fumes before going in to sleep. As long as you can pick the smell of the insecticide, you must not sleep in the room.
“Studies have shown that continuous exposure to the pesticide could lead to neurotoxicity, adverse reproductive and immunological effects as well as cancers of the blood and brain, pancreas and prostate in humans.
“For instance, the decrease in blood levels was due to a quick breakdown in red blood cells in body circulation as well as a suppression of red blood cell production by the accumulated insecticide in the body system.
“Apart from its adverse effect on kidney functions, the insecticide has a proven lethal effect on sperm production. It impairs sperm production in the testes.”
Dichlorvos has been banned in EU since 1998. The United States Environmental Protection Agency has reviewed the safety data of dichlorvos several times.
In 1995 a voluntary agreement was reached with the supplier, which restricted the use of dichlorvos in many, but not all, domestic uses, all aerial applications, and other uses.
A 2010 study found that each 10-fold increase in urinary concentration of organophosphate metabolites was associated with a 55 to 72 per cent increase in the odds of Attention deficit hyperactivity disorder (ADHD) in children.