Zinc is a metal that is necessary for human life, but dangerous at high concentrations. Zinc is used in batteries and pennies and die casting for cars. It occurs naturally in soil but more is being released into the environment by humans, especially from mining. Plants use zinc in creating chlorophyll, but in areas where soil is contaminated by zinc, only certain plants can grow.
Zinc Carried by Water
Zinc can be carried by water. Water that runs by mining operations, disposal sites, or other highly concentrated areas can carry zinc to agricultural areas and adversely affect the plants.
Too Little Zinc
Zinc is a component of protein for the plant so the roots may be reduced without it. If there is not enough zinc, the plant may have small, yellow and bunched leaves, according to Garden Guide.
Too Much Zinc
Too much zinc can disrupt the life in soil, creating a hostile environment for earthworms and microorganisms. Plants rely on a rich life in the soil to break down and make nutrients accessible. Plants do not have a good way to dispose of zinc that gets into their systems, which can make them die. Vegetables and other crops may be sensitive to zinc levels.
Zinc Passed Along
Zinc can get into plants in excess and be passed on to those who consume the plant. Both humans and animals can suffer from too much zinc. Too much zinc in humans can cause stomach problems and interfere with the absorption of other minerals. One additional problem in animals is that excess zinc intereferes with their ability to taste and smell, in which case they suffer from malnutrition, says tasteandsmell.com.