**4. Conclusions**

Pesticides in groundwater are as a result of percolating irrigation water that has been treated with pesticieds into the groundwater. In areas where soil cover is thick with clays such as montmorillonite that have the capacity to trap organometallic and organic molecules, the attenuation of pesticides can be appreciable. Soil is not an effective filter, and some

Should We Be Concerned with Long-Term Health

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groundwater aquifers will be contaminated where prolonged use of pesticides is practiced.In the case where ephemeral rivers flow throughirrigated land, they serve as a mechanism to re-distribute pesticides in the groundwater aquifers. Where flooding is frequent, the same mechanism of redistribution of pesticides occurs. The long-term effects pesticides in groundwater are much more long lived, and are difficult to remove from the aquifers. Hence their effects will be cumulative on the communities using the aquifers.The effects of pesticides on human health has now been shown to have several health effects with long term effects that need to be minimized or avoided.
