Iron is a highly reactive element with a strong tendency to oxidize in oxygen-containing environments. It is the fourth most abundant element by mass and a major component of the Earth’s core and outer layers.
Iron has a silvery white appearance but is extremely soft, allowing it to be hammered into sheets or drawn into wires. It is also very magnetic and conducts heat well. It is very reactive to acidic conditions and oxidizes rapidly in air to form hydrated iron oxides, commonly known as rust.
In the human body, iron is essential for making hemoglobin, a protein that transports oxygen in blood from the lungs to all parts of the body. It also helps form myoglobin, a protein that is involved in skeletal muscle contractions.
The most common dietary source of iron is red meat, poultry, fish (especially oysters), fortified breakfast cereals, dark green leafy vegetables (such as spinach and kale), eggs, tofu, and legumes, such as beans. A diet low in iron can result in a condition called iron deficiency, which may be characterized by symptoms including fatigue, weakness, and a decreased appetite. If these signs are present, it is recommended to see a doctor for an evaluation of the need for dietary supplements containing iron.
There are several types of supplemental iron available, including ferrous gluconate tablets, liquid drops, and slow-release capsules. Some clinical studies have shown that liquid iron is better absorbed than the standard ferrous sulfate tablet, but it contains less elemental iron. Slow-release capsules have the advantage of reducing the likelihood of gastrointestinal side effects, but they are more expensive and usually contain less iron than the standard ferrous sulfate.
Supplemental iron can be harmful if taken in excessive quantities or for prolonged periods of time, but this is rare since the body will usually regulate intake. Excessive iron can occur from taking high-dosage supplements or from a hereditary condition called hemochromatosis, in which excess iron is stored in the liver and other organs. If left untreated, this can lead to serious health problems, such as cirrhosis of the liver and liver cancer.
Zero-valent iron (ZVI) has the potential to be used for the remediation of organohalide contamination in groundwater, particularly trichloroethene (TCE). To improve the reactivity of ZVI and to make it more selective for organohalides, it can be conditioned in a sulfate-reducing bacteria culture. The resulting product is called sulfur-amended zero-valent iron (SAZVI). This study will evaluate the effectiveness of SAZVI to reduce TCE in groundwater. The results will provide guidance for future work to assess the use of SAZVI as a remediation tool in other locations and contaminants.