Quarterdeck Volume 4, Number 3, Winter 1996
Ecotoxicology in Azerbaijan
John W. Bickham
The Republic of Azerbaijan is facing perhaps the most serious ecological challenge in its history at a time when it is poorly prepared to deal with such a crisis. Notwithstanding the fact that the country has an adequate supply of well-trained scientists who are aware of the serious environmental problems and capable of addressing such issues, the resources available to them are woefully inadequate.
For example, the salary of Azeri scientists working for the government agencies is only about $15 per month, which requires scientists to maintain two jobs. Support for laboratories and offices is virtually nonexistent. Our studies of the ecological effects of pollution in Azerbaijan consist of a collaborative research program involving scientists from the Institutes of Physiology and Zoology of the Azerbaijan Academy of Sciences, the Departments of Wildlife and Fisheries Sciences and Oceanography at Texas A&M University, and Battelle Memorial Institute, a private environmental research firm. Funding for the program comes from Amoco Corporation.
We investigate the effects of oil pollution and industrial wastes on terrestrial and aquatic organisms. These studies include laboratory experiments designed to test the acute toxicity and damage to DNA caused by exposure to contaminated sediments from Baku Harbor and the industrial center of Sumgait. Baku Harbor is heavily contaminated with crude oil that leaks from various sources, especially from the nearby oil fields and a refinery. At one time, Sumgait contained about 80% of the industrial chemical manufacturing capacity of the Soviet Union. Although it operates only at about 15% capacity today, a tremendous amount of waste exists that is slowly being released into the Caspian Sea. Ecological dead zones exist in Baku Harbor and all along the north shore of the peninsula (see map on page 8).
Sturgeon represent an important source of foreign capital for Azerbaijan. At one time, the Caspian Sea sturgeon fishery produced 90% of the world's caviar. The catch has declined steadily since the 1930s as a result of overfishing, poaching, pollution, and damming of the spawning rivers. To compensate for the lack of natural spawning, 17 production hatcheries were built in the states surrounding the Caspian Sea.
The Kura River provides a good example of the problems faced by the fishery. This is the largest river in Azerbaijan and historically has served as a spawning habitat for the six native Caspian Sea sturgeon species. The river is polluted as a result of agricultural practices in Azerbaijan and mining and industrial activities in Georgia and Armenia. Two dams on the Kura River in Azerbaijan have an even greater impact on the sturgeon populations. In May 1996, we visited the huge hydroelectric dam at Mingechaur and found an impressive electrical generating facility, but there is no fish ladder to provide access to the upstream spawning-grounds necessary for the survival of the Kura River sturgeon stocks. The hydroelectric station was commissioned in 1954, so no natural spawning of these stocks has occurred for over 40 years.
Three sturgeon hatcheries on the Kura River sit at the mouth of the river, at Neftchala, and at Ali Bayramly. Although these hatcheries have reduced their productivity since the fall of the Soviet Union, they still operate and produce on the order of a few million fingerling sturgeon each year. The purpose of these hatcheries is to artificially spawn sturgeon, grow the animals in tanks and ponds for about three to four months, and then release them into the wild to supplement the natural spawning.
Unfortunately, this process is not designed for the conservation of the native Kura River populations of sturgeon because the specimens used for breeding are caught at sea by commercial fishermen. It is unknown from which spawning stock, or stocks, the breeders are taken. It is highly likely that the sturgeon stocks native to the Kura River are extinct or nearly so. Nonetheless, the fish hatcheries probably perform a very useful function in supplementing natural spawning, but as far a we know, no data exist by which the system can be evaluated.
Due to the economic importance of sturgeon, their availability through the fish hatcheries, and the sensitivity of these animals to pollution, we have used Acipenser gueldenstaedti as an experimental model to test the toxicity of the sediments in Baku Harbor and at Sumgait. Our data show that both larvae and fingerlings are highly sensitive to exposure to these sediments.
Acute toxicity studies of sturgeon exposed to Baku Harbor mud resulted in 40% mortality for fish exposed to 2.4 parts per thousand of harbor sediment in clean water for three days. We also found evidence that the frequency of micronuclei in blood cells increased with the corresponding increase of exposure rate in the survivors of the acute toxicity study. Micronuclei result from chromosomal breakage in the cells of the anterior kidney which produce the red blood cells. Their frequency is a commonly used estimator of damage to DNA. Chemical analyses of the sediment have shown the presence of great amounts of highly mutagenic polycyclic aromatic hydrocarbons, a major component of crude oil. Similar studies are presently underway using sediment contaminated with industrial waste from Sumgait.
DNA damage, like that demonstrated here for sturgeon, can reduce health and viability and cause heritable genetic changes. Thus it has a potentially devastating effect on the fish populations. Our studies have shown that the most economically important fishes in the Caspian Sea are highly sensitive to the effects of industrial pollutants. This, combined with the problems of overfishing and damming of the rivers, could contribute to the ultimate demise of the fishery.
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Last updated January 31, 1997