The world's oldest and deepest waters are not immune from contamination, warn scientists. It had been assumed that "fossil" reserves found hundreds of metres underground would be largely untouched by modern water sources. But sampling from some 10,000 wells shows this not to be the case

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The world's oldest and deepest waters are not immune from contamination, warn scientists. It had been assumed that "fossil" reserves found hundreds of metres underground would be largely untouched by modern water sources. But sampling from some 10,000 wells shows this not to be the case