Certainly, distance from the source and dilution in the atmosphere lowers exposure risk.

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Tyrrell says that unlike with widely dispersed asbestos, the pattern in most toxic-tort cases is to settle with everyone living some critical distance from the source.

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In the specific case of maize, to ensure that seed stocks achieve 99.9% purity, a separation distance of 200 metres is required from any source of "contaminating" maize pollen.

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So if birds were the source, it seemingly would mean they feasted on carp, flew a long distance and excreted feces within a few hours of when the researchers collected water samples.

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Ambient radio waves have largely been ignored as a potential power source until recently, because the power of a broadcast radio signal rapidly decreases with distance.

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According to a source with a stake in the region, many larger stake firms have kept their distance as not to hurt their partnerships with countries that would not be keen on collaborating with Israel.

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Police searched the suspect's home, "a short distance" from the temple, on Sunday evening, according to a law enforcement source with direct knowledge of the investigation.

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