Can the avian influenza contaminate air or water and what disposal options are recommended?
Category: Food, Water, & Air Safety Questions
Answer:
The Environmental Protection Agency (EPA) believes that safe disposal can be conducted with proper site-specific consideration. EPA is aware that transporting infected carcasses could increase the risk of contaminating other areas, including air and water; however, these risks can be minimized with proper biosecurity measures (or precautions taken to minimize the risk of introducing an infectious disease into an animal population).
Any burial or landfill plan will need to carefully consider the distance to water bodies and wells, the depth to the water table, soil type and depth, temperature, weather, odor potential, and impact to public, private or agricultural wells.
While there are no documented human cases of avian flu caused by exposure to highly pathogenic H5N1 avian influenza (HPAI H5N1)-contaminated water, it is important to be aware of the potential for such exposure. Potential disease transmission through natural waters, e.g., ponds where wild birds gather, is also one reason why physical separation (e.g., bio-security) of commercial flocks from wild birds is important. While HPAI H5N1 has not been found anywhere in the United States, as well as the rest of North America, or in Central and South America, it is possible that it could. However, a detection of HPAI H5N1 in birds would not signal the start of a human flu pandemic and a detection in wild birds would not mean HPAI H5N1 will reach commercial poultry.
Equipment design, operation, and maintenance are important considerations when evaluating incinerators and air curtain burners as disposal options. The design should provide sufficient temperature and residence time to destroy the materials being burned. Proper equipment operation could include preheating of primary or secondary burners to minimum temperatures prior to charging, and not exceeding the maximum suggested charging rates. Maintenance of the burners, burning chambers, fans, and instrumentation also is important to reduce air emissions and to completely destroy the waste. Air emissions from combustion of the waste, include particulate matter, nitrogen oxides, carbon monoxide, sulfur dioxides and visible emissions; air emissions from the equipment will disperse over the general area surrounding the incinerators. Stack height, exhaust temperatures, and meteorology (e.g., wind speed and direction) are also important factors that affect dispersion.
Although open burning is not recommended by EPA due to air emissions, it is considered an option in some states. If open burning is considered, and allowed under state or local laws, prior consultation with the appropriate public health and environmental officials is strongly recommended. Previous experience in other countries that have utilized open burning to control a foreign animal disease outbreak suggests that it should only be considered as a last resort after all other disposal options have been considered. Any method to burn or incinerate the waste must comply with all applicable state and local air permitting requirements.
In addition to viral fate and transport, burial or landfilling will need to consider more traditional pollutant contamination such as ammonia from carcass degradation. These considerations are also identified in USDA disposal guidance.
Related Water & Air Safety Question
Last Updated: 05/22/2007
