Before revision: In other cases, the presence of specific chemical species may produce toxic effects limiting growth and abundance of living matter.Metcalf & Eddy pp.256-258&492 Metals Many dissolved or suspended metal salts exert harmful effects in the environment sometimes at very low concentrations.
After revision: In other cases, the presence of specific chemical species may produce toxic effects limiting growth and abundance of living matter.Metcalf & Eddy pp.256-258&492 Metals Many dissolved or suspended metal salts exert harmful effects in the sometimes at very low concentrations.