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Home >> Biology >> Environmental Pollution >>Soil Pollutants and Their Effects
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Some Soil Pollutants and Their Effects
1. Fluorides.
They combine with Mg2+ of chlorophyll and hence inhibit photosynthesis, cause leaf abscission and of fruit. Maize is the sensitive indicator of fluoride pollution. In human beings mottling of teeth (fluorosis) is an indication of fluorination. Bone fluorosis results in weak bones, boat shaped posture and knocking of knee.
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2. Nitrogen fertilization (nitrates + nitrite).
Toxic concentration in leaves and fruits enters into food chain. In alimentary canal, activity of bacteria changes nitrates into nitries. The latter entres blood and combine with haemoglobin to form met6-haemoglobin so oxygen transport is reduced. It give rise to disease called methanaemoglobinaemia. In infants it cause cyanosis (blue babies due to bluish tint of skin). Nitrate poisoning is fatal unless methylene blue is injected (in infants) while in adult it produces breathlessness.
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3. Weedicides.
They are usually metabolic inhibitors which stop photosynthesis and other metabolic activities killing the plant. Some causes death due to proliferation of phloem cells to block transport of organic food.
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