M JOAN B. ROSE
Action is needed to safeguard our drinking
water supplies from a bioterrorist attack.
he horrific events of September 11 and the outbreak of anthrax cases that followed have brought the issue of security to the forefront of everyone’s agenda. Risks that were deemed highly unlikely have now become risks for which we should be prepared. This is particularly true for the water industry. From the perspectives of health and economics, water is the lifeblood of communities. Water safety has always been of the highest priority, but in this climate of general concern, communities and the water industry have to deal with the specifics of water security. In response, the American Water Works Association and the Association of Metropolitan Water Agencies started working with EPA in October and released a list of 25 water security recommendations. Not one of these items addresses water quality, preparedness, and testing. This is a significant oversight. In a statement before the House Committee on Transportation and Infrastructure Subcommittee on Water Resources and Environment on October 18, 2001, FBI Deputy Assistant Director Ronald Dick said, “Based upon available intelligence and investigative information, there are no specific credible threats to major waterways or distribution networks at this time. Because of the vital importance of water to all life forms, however, the U.S. Federal Bureau of Investi-
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© 2002 American Chemical Society
gation (FBI) considers all threats to attack the water supply as serious threats.” EPA Administrator Christine Whitman has said she agrees that water is not a major target and the threat would be minimal. I believe that the knowledge base used by the government to justify this stated sense of security for water supplies is inappropriate. It is built on a significant misunderstanding of the issue and a lack of science- and risk-based information. Contrary to the FBI and EPA appraisal, scientists and water specialists report that the nation’s water supply is indeed vulnerable (1). The water industry therefore must assume that water resources are at risk and develop a preparedness plan for monitoring, communication, and decontamination in the event that a bioterrorist’s attack on the water supply occurs.
What are the biological threats? Several publications list microorganisms that could potentially be used as biological weapons. For example, Burrows and Renner identify 18 organisms and 9 biotoxins, of which 44% and 89%, respectively, are listed as water threats and another 28% and 11%, respectively, are considered probable water threats (see Table 1 on next page and Table 2 on page 249A) (2). The enteric bacteria, such as Vibrio cholera, Salmonella, and Shigella; protozoa, such as CryptoJUNE 1, 2002 / ENVIRONMENTAL SCIENCE & TECHNOLOGY
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TA B L E 1
Microbial threats to potable water supplies Agent/disease
Water Weaponized threat
Anthrax Brucellosis Cholera Clostridium perfringens Glanders Melioidosis Plague Psittacosis Q fever Salmonella Shigellosis Tularemia Typhus Encephalomyelitis Enteric viruses Hemorrhagic fever Smallpox Cryptosporidiosis
Yes Yes Unknown Probable Probable Possible Probable Possible Yes Unknown Unknown Yes Probable Probable Unknown Probable Possible Unknown
Yes Probable Yes Probable Unlikely Unlikely Yes Possible Possible Yes Yes Yes Unlikely Unlikely Yes Unlikely Possible Yes
Infective dosea
Stability in water
Chlorine toleranceb
6000 spores (inh) 10,000 organisms (uns) 1000 organisms (ing) 108 organisms (ing) 3.2 × 106 organisms (uns) Unknown 500 organisms (inh) Unknown 25 organisms (uns) 104 organisms (ing) 104 organisms (ing) 108 organisms (ing) 10 organisms (uns) 25 particles (aer) 6 particles (ing) 105 particles (ing) 10 particles (uns) 132 oocysts (ing)
2 years (spores) 20–72 days Survives well Common in sewage Up to 30 days Unknown 16 days 18–24 hours in seawater Unknown 8 days, fresh water 2–3 days Up to 90 days Unknown Unknown 8–32 days Unknown Unknown Stable days or more
Spores resistant Unknown Easily killed Resistant Unknown Unknown Unknown Unknown Unknown Inactivated Inactivated, 0.05 ppm, 10 minutes Inactivated, 1 ppm, 5 minutes Unknown Unknown Readily inactivated (rotavirus) Unknown Unknown Resistant
Abbreviations:aer = aerosol; ing = ingestion; inh = inhalation; uns = unspecified; ppm = parts per million. aTotal
infective dose used to calculate water values. temperature,
