Attack of the Heavy Metals

As a (mostly) transition metal chemist, I enjoy heavy metals -- the elements, not the bands. Heavy metals should be a part of any self-respecting chemist’s lab. But they shouldn’t be part of our ecosystem, at least not in the levels associated with human use. The health effects can be serious. Industrial waste, residential garbage (you do recycle your Ni-Cd batteries, don’t you?), and certain pesticides all lead to elevated levels of these elements. I now read that heavy metals are a concern in organically grown foods. Not the first place I would have associated with toxic materials. The whole point of organic growing techniques is to be more biofriendly to the environment by using recycled organic matter instead of synthetic fertilizers. Unfortunately, these organic fertilizers, “composted animal manure, rock phosphates, fish emulsions, guano, wood ashes, etc.” can contain significant levels of these metals. Now this does not necessarily mean that heavy metal concentrations are always higher in organically managed soils, but it has been observed and is a concern. Regulations are tightening and research is continuing, but as we release more and more metals into the environment, the differences between organic and nonorganic farming may become smaller and smaller.

Of course, this is an example of unintentional exposure to heavy metals. Some health practitioners actually want you to ingest heavy metals for your own good. For example, Ayurvedic medicine, based on an ancient practice, uses herbal remedies for a wide variety of illnesses. In the practice of Ayurveda, “…a balance of the metals, including lead, copper, gold, iron, mercury, silver, tin, zinc are considered to be essential for normal functioning of the human body and an important component of good health.” So these metals are often added to Ayurvedic medicines. Unfortunately, there have apparently been reports of heavy metal poisoning related to the use of these medicines, especially in the case of lead. Again, regulations are tightening, but it’s hard to control substances you can buy over the Internet.^*

I think I’ll just stick with playing with my metals in the lab.
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^*Why is the Internet always capitalized? Are there religious connotations here?