Q1. Define what a heavy metal is and give some examples.
Heavy metals are naturally occurring metallic substances on the earth characterized with a high density and have a toxic nature to biological organisms. Examples of these metals include mercury, lead cadmium, arsenic, tin and chromium. Continued human exposure to these metals can cause serious health complications.
Q2. Describe some of the effects that heavy metals have on biological systems and discuss some of the ways they enter our system.
Mercury is, without doubt, among the world’s most poisonous and dangerous heavy metals found naturally on earth. It exists in large quantities in gold, silver mines or on its own as a metal ore. Mercury is one of the most expensive metals on earth due to its high density nature. Besides its immense value in life, mercury poses a threat to human life. The toxic nature depends on the chemical form that it takes in human bodies. Methyl mercury is the most toxic form (Mohammad 25). It affects the human immune system, damages the nervous system and alters the human genetic system. Human body takes up methyl mercury fast, but it excretes slowly. The other form of mercury is elemental mercury. It occurs mainly when substances holding mercury breaks. It can also be found in abundant in gold mines when it is part of the process for gold extraction. Elemental mercury causes digestion problems and kidney failure. A National Research Council report (69) suggested that negative effects of mercury on humans were as a result of consuming contaminated fish.
Lead is a soft, heavy, gray metal naturally occurring on earth. Humans use it widely in homes and factories since it is relatively cheaper than other metals. Overexposure to lead causes brain damage, high blood pressure, blood anemia and bone weakness while low exposure to lead causes slowed mental and physical growth in children, as well as learning disabilities. Lead poisoning comes from consumption of contaminated food. In homes, people use lead for roofing since it is cheap (Mohammad 40). Rain water may collect in storage tanks and humans may use it for cooking and drinking. Often such domestic use of water will lead to lead poisoning. Companies also use lead to make paints and batteries. Children may expose themselves to lead when playing with discarded batteries, and may end up consuming lead when they eat without properly washing hands.
Arsenic is grayish in color and exists in large quantities on earth. Human beings may expose themselves to it through water, soil or air. Arsenic occurs in two different types: organic and inorganic. There are no reports on the effects of organic arsenic. However, inorganic arsenic, which contains oxygen, chlorine and sulfur, causes lung, bladder, kidney, liver and prostate cancer. Overexposure of pregnant mothers to arsenic causes low child development and low brain development leading to low IQ levels.
Cadmium is one of the widely used metals on earth. It is used in electroplating, making paints and batteries. Overexposure to cadmium causes lung cancer, kidney failure and liver complications. Several people have died from usage of cadmium in factories or when welding using cadmium alloys. Cadmium effects can also be felt from using batteries manufactured using cadmium. When used in welding, cadmium emits a non-irritating blue frame. As such, a welder will not have cause of alarm using it leading to poisoning.
Q3. Using at least two documented examples for background information, propose a hypothesis for the effects of heavy metals on the preservation of mummies and design a simple experiment to test your hypothesis.
Background Information
People can still use heavy metals for the preservation of mummies, regardless of the negative effects these metals pose to people and the environment. Firstly, People have over periods used arsenic for the preservation of soft tissues. This is evidence in the case of Elmer McCurdy, a young cowboy in USA who lived during the nineteenth century (Author 52). The case involves Arsenic fluid that maintained the body structure for a long period to permit its display at carnivals over a century later after his death. Researchers also found a number of mummies buried in Camarones River in Northern Chile. This River contained high concentrations of arsenic compounds, which was similar to high exposure of human tissues and skin on arsenic compounds. Lastly, health scientists have criticized the use of mercury, but it has proved extremely effective in the mummification process. This is evidence in a Swiss Franciscan case in the sixteenth century. His people used mercury ore to mummify his body. Mercury mummification was also found in a body of a Chinese woman who died 2000 years ago. Anthropologists found mercury ions in the coffin of this woman (Author 53). Apart from the negative effects of heavy metals on humans and the environment, heavy metals, on the other hand, offer exceptional support in mummification of humans. Scientists should develop a way using such metals in the mummification process just as ancient people did. Scientists should get dead bodies from mortuaries to carry on mummification analysis on them. Using knowledge obtained from above examples, scientists will select bodies they wish to carry their research on and then introduce different kinds of heavy metals on different samples. Researchers should introduce conditions necessary for bodies to rot and then check on the sample bodies to see whether there are changes to them.
Hypothesis
Considering the harmful nature of heavy me