This week, Professor Liao will introduce heavy metals exposure to human health. There are two parts this week. First, he will show you the definition of heavy metals and toxic metals, and why we should be concerned about toxic metals. And the second part, he will introduce major toxic metals, including arsenic, cadmium, lead, and mercury.
Professor Liao will explain why there are heavy metals in our food. Metals are redistributed naturally in the environment by both geological and biological cycles. For biological cycles, human activities shorten the residence time of metals in ore deposits and greatly enhance metal distribution in the global environment by discharge into the soil, water, and air. Metals via biomagnification by microorganisms, plants, and animals result in incorporation in food cycles.
The main routes of human exposure to metals include oral ingestion, inhalation, and dermal contact. Hence, many different sources of both natural and anthropogenic character are responsible for the presence of toxic metals in the surrounding environment. Once released into the environment, the toxic metals are via various routes into the food chain.
Are you aware of the possible hazard of heavy metals intake?