TCS Daily

The Paraquat Principle

By Duane D. Freese - December 16, 2003 12:00 AM

It's rarely wise to throw caution to the wind. But the precautionary principle? As it is currently promoted by some environmental organizations and practiced by some countries, it deserves to be blown away.

The problems of the principle received a thorough airing from its critics at a forum sponsored by the Marshall Institute, a Washington-based think tank focusing on science policy. The forum at the National Press Club last week, "Uses and Misuses of Science in Regulating Chemicals: Unintended Consequences for the Developing World," reviewed application of the precautionary principle to new biotechnology products, old restrictions on DDT and new restrictions on an old tried and true herbicide, paraquat.


Henry Miller of the Hoover Institution and founder of the Food and Drug Administration's Office of Biotechnology noted that environmental organizations don't seek "prudent, safe use" of such old chemicals as paraquat or new biotechnology products "but their complete elimination."


"A large number of people in poor nations have food allergies," he pointed out, including to such common foods as milk, wheat and nuts. "Biotechnology can remove the allergens ... so people in developing countries can enjoy some of these foods."


But environmental groups, such as Greenpeace, are using the precautionary principle to oppose development of those products and others that would improve agricultural productivity, Miller argues, not because they are dangerous, but because of a social vision that is "anti-business, anti-technology and anti-American."


The Case of DDT


Roger Bate of the health advocacy organization Africa Fighting Malaria and a frequent contributor to TCS pointed out that the restrictions placed by developed nations on the pesticide DDT are especially dangerous to the health of people in poor countries.


The European Union's targeting of 12 chemicals, including DDT, based on the precautionary principle, Bate said, ignores "the risk profiles of nations at different stages of development." Poorer nations, in short, simply can't afford some of the more elaborate bureaucratic controls that rich nations place on the use of many pesticides, he argued.


DDT, he said, is vital to combating malaria, dengue fever and locusts -- scourges that still kill hundreds of thousands in developing countries. The developed world's controls put on DDT, which can delay imports for nearly six months, are leading to black markets and the development of less-safe imitation chemicals, he said.


The precautionary principle's prescriptions, he said, "have hampered trade, are hurting economic growth and are damaging health."


The Case of Paraquat


Some of the most serious questions about motives behind the use of the precautionary principle by environmental groups came from the presentation by Prasanna Srinivasan of Business Environment Assessments and an expert on developing countries' economics.


Srinivasan released a new study sponsored by 30 organizations from 13 countries, Paraquat: A Unique Contributor to Agriculture and Sustainable Development.


Paraquat is the most widely used herbicide in the developing world and has come under increasing attack by environmental groups, who claim it is dangerously toxic to humans.


"In addition to health hazards, regulators are concerned that the chemical is persistent and accumulates in soil. Studies indicate that paraquat has adverse effects on mammals, birds, fish and amphibians. In Sweden we believe that, for the environment and for health, the only safe use is no use," Göran Eklöf  of the Swedish Society for Nature Conservation argued this fall when a European Union scientific committee found paraquat safe for use in the EU.


Srinivasan found most of such claims to be simply false. On claims of dangers of persistence in soil, for example, Srinivasan found that paraquat is, in essence, "environmentally benign." It binds to clay soils and doesn't affect soil life or leech into groundwater. It then degrades and "doesn't create any toxic effects in the breakdown," he said. Further, because it doesn't destroy roots, it prevents soil erosion, which is especially important in tropical regions, Srinivasan argued.


As to human health effects, paraquat droplets are such that inhalation poses little health threat, although it can in circumstances lead to bloody noses, Srinivasan found. It doesn't absorb through the skin and can be washed off, he noted, and Syngenta, the major maker of paraquat herbicides, has added a foul smell, dye and an emetic to help prevent and protect against any accidental ingestion of the herbicide.


 "The big problem is if there is deliberate consumption for the purposes of suicide," Srinivasan found. Pesticides are popular tool in suicides, he noted, and as one of the more common pesticides, paraquat is among those most used


According to the Food and Agricultural Organization and World Health Organization, paraquat "may be absorbed through the gastrointestinal tract. Paraquat is not absorbed to any great extent by intact skin and there is no evidence of significant absorption from spray mist. ... Repeated daily six-hour exposure of rats to paraquat aerosols over a three-week period produced signs of lung irritation but no deaths. ... Fish - Not hazardous: rapidly absorbed by aquatic plants and inactivated in mud. Birds - Not highly toxic. No hazard under normal conditions of use. ... Protective clothing should be provided for those handling concentrates. Adequate washing facilities should be available close at hand. Eating, drinking and smoking should be prohibited during handling and before washing after handling."


And paraquat, along with other pesticides, Srinivasan argued, serves a vital need. Even with them, crop losses annually amount to about 33 percent to 42 percent of world production. Without them, though, crop losses would amount to 80 percent. And without the productivity enhancements such chemicals provide, the world would use more than double the 38 percent of arable land now used for agricultural purposes -- an additional 14.1 billion acres, or 44 percent of the land available on Earth, Srinivasan said.


So, why the pressure from environmental groups that pesticides, in general, and paraquat, in particular, be banned? Why the attempt to intimidate the EU science commission approving the sale of paraquat in Europe by EU environmental groups?


To Srinivasan the answer is that "certain extremist environmental groups ... seem to be more concerned with power than the truth." That is no reason, though, "to deny access to cost effective technology," he said.


His own principle to counter the precautionary principle is simple: "To protect the farmers' rights wherever they may be to use whatever products and technologies they need."


Will the rights of farmers -- and consumers and producers -- blow away the precautionary principle in its many deadly manifestations? We'll have to wait and see.

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