Industrialization and modern methods of insect control have improved the standard of living around the globe while at the same time they have introduced some 100,000 dangerous chemical pollutants, having gone virtually unregulated since they were developed more than 50 years ago.


while at the same time they have introduced some 100,000 dangerous chemical pollutants, having

while at the same time introducing some 100,000 dangerous chemical pollutants that have

while they have introduced some 100,000 dangerous chemical pollutants at the same time, which have

but introducing some 100,000 dangerous chemical pollutants at the same time that have

but at the same time introducing some 100,000 dangerous chemical pollutants, having

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Prep2007E1-SC