ANALYSES AND DETERMINATION OF THE CHEMICAL COMPOSITIONS OF MOSQUITO REPELLANTS SOLD IN IMO STATE, NIGERIA – INDICATING THEIR LEVELS OF ECO-FRIENDLINESS AND TOXICITY

A lot of persons make use of mosquito repellants in order to be free of mosquito bites irrespective of the aftereffects of these repellants. More serious illnesses other than those infected by mosquitoes seem to arise from some of these repellants. In this research, the chemical composition and safety profile of various chemically synthesized mosquito repellants commonly used in Imo State, Nigeria were carried out. X-ray fluorescence was done to find out the elements present in each. GC-MS analyses were carried out to identify the organic compounds while the ADMET (toxicity) test was followed to evaluate the level of toxicity in each repellant. From the GC-MS analyses, it was deduced that six of the ten types of repellants analyzed contain a non-friendly compound generally known as DEET (Diethyltoluamide). These are medi soft cream with 3.567% of DEET, gardia cream = 22.544%, fly killing bait powder = 7.602%, Rambo coil = 2.822%, reptogel cream = 7.972% and super kill coil = 0.094% all by mass. X-ray done indicated the presence of lead, a harmful element though found at a low concentration in medi soft cream, super kill coil, Swan Green coil, Rambo paper, Rambo coil, odomos cream and fly killing bait powder. Sulphur too detected in Rambo powder, Rambo coil and reptogel cream seems not threatening. Considering the ADMET test, it reveals that most of these repellant are not safe especially when applied for long as each of their prediction toxicity does not correspond to a manageable extent to the DrugBank% database. Odomos cream with no DEET and no elemental sulphur may be less toxic as its toxicity prediction tallies more with the DrugBank% data base. This research therefore recommends that the use of chemical mosquito repellants be discouraged till the producers get back to the drawing board. Natural repellants could be resorted to.