What makes silica toxic?

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      <subfield code="a">What makes silica toxic?</subfield>
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      <subfield code="a">Published data suggest that particle charge could be related to its toxicity. Respirable particles containing silica were therefore collected in foundries and their charge measured. These particles carried high levels of positive charge that were related to low humidity. incubating these particles with pulmonary macrophages from mice produced detectable activities of collagenase, aprecursor of silicosis. These experiments confirm that the toxicity of silica particles is likely to be because of the positive charge they carry</subfield>
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      <subfield code="a">British journal of industrial medicine</subfield>
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      <subfield code="t">British journal of industrial medicine</subfield>
      <subfield code="d">London and Margate</subfield>
      <subfield code="g">nº 3, March 1992 ; p. 163-166</subfield>
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