The key difference between heavy metals and trace elements is that the heavy metals are usually toxic at very low concentrations whereas the trace elements are not toxic at low concentrations.
Heavy metals are usually high dense materials with high atomic numbers and atomic weights. These are toxic even in very low concentrations. However, there are some non-toxic heavy metals such as gold, which are non-toxic due to the highly unreactive nature of the element. In contrast, trace elements are micronutrients which we need in minute amounts for the growth and development of our body. Therefore, these are dietary elements.
CONTENTS
1. Overview and Key Difference
2. What are Heavy Metals
3. What are Trace Elements
4. Side by Side Comparison – Heavy Metals vs Trace Elements in Tabular Form
5. Summary
What are Heavy Metals?
Heavy metals are dense materials having high atomic numbers and high atomic masses. Usually, these metals are toxic. However, there are some non-toxic metals as well. Ex; gold. Gold id not toxic because it is highly unreactive. The specific gravity of these metals is higher than 5.0. These metals include transition metals, metalloids, lanthanides, and actinides.
Most common metals such as iron, copper, tin and precious metals such as silver, gold, and platinum are heavy metals. Some of the heavy metals are nutrients which are essential for our body. Ex: iron, cobalt. Heavy metal poisoning usually occurs at mining, tailing, industrial waste management, exposure topaints, etc.
What are Trace Elements?
Trace elements are micronutrients we need in minute amounts for the growth and development of our body. These are dietary elements. This means we can get these elements via food. These elements are essential for us but in trace quantities.
Figure 01: The Trace Elements and Macronutrients We Need
Most of the times, we can find these elements as part of an enzyme. Some examples for trace elements include copper, boron, zinc, magnesium, molybdenum, etc. Lack of these elements may cause disorders in animals and plants.
What is the Difference Between Heavy Metals and Trace Elements?
Heavy metals are dense materials having high atomic numbers and high atomic masses. Almost all the heavy metals (except gold) are toxic even in very low concentrations. Moreover, these metals have a very high density. Trace elements are micronutrients which we need in minute amounts for the growth and development of our body. Unlike heavy metals, trace elements are not toxic but can be toxic at very high concentrations. In addition, these metals have a low density.
Summary – Heavy Metals vs Trace Elements
Heavy metals are considered toxic elements. Trace elements are micronutrients. However, some trace elements are also categorized as heavy metals. However, these elements do not harm us since we need them in very minute amounts. The difference between heavy metals and trace elements is that the heavy metals are usually toxic at very low concentrations whereas the trace elements are not toxic at low concentrations.
Reference:
1. Helmenstine, Anne Marie. “Are All Heavy Metals Toxic?” ThoughtCo, ThoughtCo. Available here
2. Britannica, The Editors of Encyclopaedia. “Trace Element.” Encyclopædia Britannica, Encyclopædia Britannica, Inc., 28 Nov. 2016. Available here
Image Courtesy:
1.’Periodic table of the chemical elements (1-118)Dietary minerals’By Tosaka – Own work, (Public Domain) via Commons Wikimedia