Choose the correct word to complete the gap in the following sentence.
We are more concerned than ever, it seems, ___________ the water we drink and the air we breathe, and are smoking less, though not yet drinking less alcohol.
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Choose the correct word to complete the gap in the following sentence.
We are more concerned than ever, it seems, ___________ the water we drink and the air we breathe, and are smoking less, though not yet drinking less alcohol.