Question

You are an employee of the EPA. You are given the task of conducting risk management for the spraying of insecticides to kill the mosquitoes that carry West Nile virus. 1. How might you determine the proper concentration needed to kill mosquitoes? 2. How might you determine whether the concentration used to kill mosquitoes might also kill other species or insects? 3. If you knew the insecticide's LD50 value for humans, what concentration would be the safe upper limit for humans? 4. Given the information you have accumulated as part of your risk assessment, describe the factors that might be important in the risk management of spraying insecticides to kill the mosquitoes that carry West Nile virus

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Answer 1

1. Take a fix population of mosquitoes and open these to changing dosage of the insecticides using spary or aerosol. Measure the reaction of each dose, the quantity of mosquitoes die from the insecticide.

(From the information, If LD50 is required dose to kill 50% of the mortality in a population. To kill all mosquitoes it required 2 or 2.5 times of LD50 dose).

2. A environment study should be done before using insecticides for certain type of harmful mosquitoes. We don't want to kill ladybug(or any other useful insects), ideally lower LD50 for mosquitoes and high LD50 for ladybugs.

3. In this case safe concentration of LD50 for human should be range between 0.1-1.0%.

4. Risk management for spraying insecticides must take quantitative measure such as economic,population, health and social factor,