However in the case of Neal Soil Suppliers - where dairy and food effluent was spread over a field - there had been "substantial and serious pollution".

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In this case, there are fears that dioxins, drifting through the air, could settle on soil or crops and somehow pass into the food chain.

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But such is their persistence that they can also be found in soil, sediment, food, air and house dust, and 97% of Americans have detectable levels in their bodies.

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This is dangerous for those who eat cadmium-laden food, and it imperils China's future food supply as the soil is damaged.

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It changes soil, preserves food, inspires polar explorers and gives hope to those in search of resurrection now that bodies can be preserved in liquid nitrogen.

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That means more nutrients in the soil, where it feeds food crops, and less in lakes and streams, where it feeds algae that sucks up oxygen and kills fish.

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An honest assessment of soil quality would put further pressure on food supplies, and challenge the government's policy of food self-sufficiency, which it believes is a strategic imperative.

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The culprit parasite, Toxoplasma gondii, can get into the food chain via cats faeces causing contamination of soil, water and plants.

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When the next food crop is planted, it benefits from the nutrients and improved physical properties of the soil that the trees have provided.

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Rather, it pairs well with food, expresses purity, floral characteristics and, of course, the mineral aspect of the soil.

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