For my international work experience requirement for IARD I spent last summer working with a

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1 Nigar Safarova Summer Study Final report Azerbaijan For my international work experience requirement for IARD I spent last summer working with a group of researchers at the Radiology Department of Baku State University in Azerbaijan. I joined the Absheron bioremediation project last June, and worked on it with the other scientists for eight weeks. I had learned many things from this project, but most important of all I gained deep insights about sustainable and ecological methods to cleanup polluted areas. I was born in Azerbaijan - a small country that is situated on the west coast of the Caspian Sea and surrounded by the Caucasian mountains. Azerbaijan has a territory of about 87,000 square kilometers, and its total population is 9.0 million. About 40% of the people live on the Absheron peninsula, which is famous for its rich oil fields and large number of oil corporations working there. The Absheron area is also notoriously known for its disastrous pollution. The main causes of pollution are the exploitation of oil and gas fields, underground water flooding, toxic wastes from the chemical industry and other factors. Particularly harmful for Absheron are heavy metal and radioactive contaminants. Heavy metals are by-products generated by different technological processes. They are released into the atmosphere and deposited on the soil surface. Copper, zinc, cobalt, lead, cadmium, nickel, and chromium are the main polluting elements. The bulk of heavy metals are located in the surface soil layers.

2 Radionuclides also contaminate vast areas of Absheron. The high level of radioactivity is observed in the areas near the oldest oil fields and near the iodine plants. For many years the Azerbaijan government was not able to prevent pollution that traditionally escaped from any form of regulatory control. Only recently have public organizations and the government launched several remediation and research projects aiming at a variety of cleanup methods and reclamation techniques. I took part in one of those bioremediation projects. The project was planned for 30 weeks and had three strategic objectives: First, develop and test different bioremediation methods for in-situ soil cleanup Second, apply the developed bioremediation techniques on a wider scale throughout Absheron. Third, evaluate the financial and ecological benefits of bioremediation on the Absheron peninsula. Bioremediation is a group of ecologically friendly methods which utilize plants, microorganisms, and invertebrate animals to clean up soil from wastes from the oil industry, heavy metals, radionuclides, and different toxic compounds. My summer project was focused on phytoremediation which is an integral part of bioremediation. Phytoremediation is a method that uses plants to reduce, remove, degrade pollution and restore land for private or public use. My colleagues and I investigated and tried to prove there were viable cleanup methods for the polluted pilot area using phytoremediation techniques. The pilot area consisted of experimental and control sites. I usually spent my mornings working on the experimental and control sites, observing and taking care of plants, and collecting samples

3 of soil and plants for the lab analyses. In the afternoons I usually worked in the laboratory, and researched the theoretical and practical aspects of phytoremediation. I learnt that phytoremediation of contaminated sites is relatively inexpensive and appears good for the public compared to alternative remediation methods, involving soil excavation and removal. What interested me most was phytoextraction. Phytoextraction focuses on cultivation of specially selected species of plants on polluted sites. It is a sustainable, in situ based technology that uses natural hyperaccumulators. Artemisia plants and foliaceous lichen are the local hyperaccumulators that are widespread at Absheron. We used them in our bioremediation project. These plants accumulate high levels of contaminants throughout their lifetime. They help to rehabilitate land contaminated with heavy metals and radionuclides without soil destruction. Artemisia plants and foliaceous lichen are the best candidates for the removal of such metals as nickel, zinc, and copper from Absheron soil. These plants use their root systems to extract heavy metals and radionuclides, which are then transferred and accumulated in the aerial part of vegetation. After the plants have been allowed to grow for some time, they are harvested and either incinerated or composted to recycle the metals. This procedure may be repeated as necessary to bring soil contamination levels down to allowable limits. If plants are incinerated, the ash must be disposed of in a hazardous waste landfill. However, the volume of ash will be much less compared to the primary contaminated soil volume.

4 In our project we were experimenting with two types of phytoextraction - continuous and induced. Continuous phytoextraction requires the use of hyperaccumulators. Induced phytoextraction requires addition of accelerants to the soil. In the case of heavy metals, chelating agents like EDTA assist in mobilization and accumulation of metal contaminants. In our laboratory soil samples were ground and passed through a 2-mm sieve and extracted by the standard DTPA-extraction method. For the total extraction of metals, soil samples were digested by a microwave in aqua regia (1HNO3:3HCl by volume). The collected plant samples were washed thoroughly with de-ionized water for decontamination from the heavy metal deposited on the leaf and root surface, and then separated into roots and shoots. Wormwood and lichen material was pulverized and ashed in glass vials at 550 C in a muffle furnace. The resulting ash was digested in 4 M HCl at 125 C on a hot plate until dry and then dissolved in 0.4 M HCl. For heavy metal analyses we used Spectral and Omega Handheld XRF Analyzers, and for radionuclides we utilized Canberra gamma spectrometer with HPG detector. All analyses were run in three replications. Our research proved the viability of phytoextraction on the polluted Absheron areas. The results indicated that Artemisia and lichens accumulated the highest level of metals on contaminated sites. Artemisia scoparia showed the best accumulation properties and represents the best phytoremediation tool for recovering polluted soil. Our researchers come to the conclusion that the success of phytoextraction is determined by specific hyperaccumulators, or in some cases, high biomass-yielding plants, and the length of treatment.

5 The experience gained from our pilot bioremediation project can be used by local organizations in all countries of the Caspian region. The environmental and climatic conditions of the Caspian countries Kazakhstan, Turkmenistan, and the South Russia are almost identical. Pollutions and their causes are similar as well as. They can be successfully treated using the methodology and procedures proved during the pilot bioremediation project on the Absheron peninsula. I have been very fortunate to work with other researchers on this project. I am going to use all gained knowledge and experience in my future career challenges.