Cole, D., Cole, R., Gaydos, S., et al.(2009). Aquaculture: Environmental, toxicological, and health issues. International Journal of Hygiene and Environmental Health, 212, 369-377.
Thailand is the largest shrimp producer in Southeast Asia with shrimp farms developed along the Thai coastline (Graslund, 2001). The shrimp farms are about 80,000 hectares, and since 1992, Thailand has produced from 150,000 to 220,000 tons of shrimp every year (Graslund, 2001). Ninety percent of the shrimp is exported to Japan, America, Europe, and other Asian countries, and shrimp export is one of the main agriculture products bringing money to the country (Graslund, 2001). However, the development of this industry has caused environmental hazards from antibiotics and pesticides, and these chemicals are mainly used to protect the shrimps from diseases and maintain the water quality (Cole, 2009 and Graslund, 2001).These chemicals can be toxic or mutagenic on the wild flora and fauna, and antibiotics can cause resistance and changing the micro-organism composition in the aquatic environment (Graslund, 2001).
Oxytetracycline, an antibiotic, is widely used by farmers; however, studies have shown that almost all of the bacteria isolated from shrimp and water samples are resistant to oxytetracycline (Graslund, 2001). Oxytetracyline can cause health hazards for farmers such as abdominal pain and burning, nausea, vomiting, discoloration of the skin, diarrhea, and liver and kidney damage (“Oxytetracyline”, 2009). Antibiotics can be carcinogenic and can cause antibiotic resistance in human consumers (Cole, 2009).
Another environmental hazard is trichlorfon. It is a toxic pesticide and mostly used in aquaculture (Graslund, 2001). Trichlorfon dissolves in water; therefore, it easily contaminates the water environment. Besides, trichlorfon degrades to dichlorvos, a more toxic and more stable form, and it can stay 526 days in the water at 20oC (“Trichlorfon”, 1993).
References: Fisheries and Aquaculture Department (FAD) (1995). Report on a Regional Study and Workshop on the Environmental Assessment and Management of Aquaculture Development. Retrieved from http://www.fao.org/docrep/field/003/AC279E/AC279E00.htm#TOC. Accessed May 20, 2012. Graslund, S., Bengtsson, B. (2001). Chemicals and biological products used in south-east Asian shrimp farming, and their potential impact on the environment-A review. The Science of the Total Environment 280, 93-131. Oxytetracyline (2009). http://datasheets.scbt.com/sc-205784.pdf. Accessed May 25,2012. Trichlorfon (1993). http://pmep.cce.cornell.edu/profiles/extoxnet/pyrethrins-ziram/trichlorfon-ext.html. Accessed May25, 2012.