Too much metal in the soil is considered pollution. Yet too little metal in a person’s diet can cause health problems. An American scientist says the answer to both problems may be plants that take up large amounts of metal in their tissues.
David Salt is an expert on plants at Purdue University in West Lafayette, Indiana. He is working with plants that store large amounts of metals.
In recent years, scientists have shown interest in using such plants to clean up harmful waste materials, Professor Salt says such plants also could be used to improve people’s diets or even to create foods that fight cancer.
Humans need a number of metals in their diets, including iron and zinc. These metals are needed in very small amounts, however. That is why they are called micronutrients. The lack of micronutrients is blamed for health problems in many developing countries. Children and pregnant women are mostly affected.
Recently, Mr. Salt an
A. Plants that absorb metals are being studied by scientists.
B. Scientists are trying to create cancer-fighting crops.
C. Some wild plants can store micronutrients naturally.
D. Anti-cancer products in the foods are good to people's diet.
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