I am often asked why I broke ranks with Greenpeace after 15 years as a founder and full-time environmental activist. I had my personal reasons, but it was on issues of policy that I found it necessary to move on.

By the mid-1980s, the environmental movement had abandoned science and logic in favor of emotion and sensationalism. I became aware of the emerging concept of sustainable development: balancing environmental, social and economic priorities. Converted to the idea that win-win solutions could be found by bringing all interests together, I made the move from confrontation to consensus.

Since then, I have worked under the banner of Greenspirit to develop an environmental policy platform based on science, logic and the recognition that more than six billion people need to survive and prosper every day of the year. The environmental movement has lost its way, favoring political correctness over factual accuracy, stooping to scare tactics to garner support.

We're faced with environmental policies that ignore science and result in increased risk to human health and ecology. To borrow from the vernacular, how sick is that?...

• Genetic enhancement: Activists persist in their zero-tolerance campaign against genetically enhanced food crops. There is no evidence of harm to human health or the environment, and benefits are measurable and significant. Genetically enhanced (GE) food crops reduce chemical pesticides, boost yield and reduce soil erosion. Enriched with Vitamin A, Golden Rice could prevent blindness in 500,000 children per year in Asia and Africa if activists would stop blocking its introduction. Other food crops contain iron, Vitamin E, enhanced protein and better oils. The anti-GE campaign seeks to deny these environmental and nutritional advances by using ''Frankenfood'' scare tactics and misinformation campaigns.

• Salmon farming: The campaign against salmon farming, based on erroneous and exaggerated claims of environmental damage and chemical contamination, scares us into avoiding one of the most nutritious, heart-friendly foods available. The World Health Organization, the American Heart Association and the Food and Drug Administration say that eating salmon reduces the risk of heart disease and fatal heart attack. Salmon farming takes pressure off wild stocks, yet activists tell us to eat only wild fish. Is this how we save them, by eating more?

• Vinyl: Greenpeace wants to ban the use of chlorine in all industrial processes. The addition of chlorine to drinking water has been the greatest public-health advance in history, and 75 percent of our medicines are based on chlorine chemistry. Greenpeace calls for a ban on polyvinyl chloride (PVC or vinyl), claiming it is the ''poison plastic.'' There is not a shred of evidence that vinyl damages human health or the environment. Apart from lowering construction costs and delivering safe drinking water, vinyl's ease of maintenance and its ability to incorporate anti-microbial properties is critical to fighting germs in hospitals. Banning vinyl would raise the cost of an already struggling healthcare system, denying healthcare to those who can least afford it.

• Hydroelectricity: International activists boast to have blocked more than 200 hydroelectric dams in the developing world and are campaigning to tear down existing dams. Hydro is the largest source of renewable electricity, providing about 12 percent of the global supply. Do activists prefer coal plants? Would they rather ignore the needs of billions of people?

• Wind power: Wind power is commercially feasible, yet activists argue that the turbines kill birds and ruin landscapes. A million times more birds are killed by cats, windows and cars than by all the windmills in the world. As for aesthetics, wind turbines are works of art compared to some of our urban environments.

• Nuclear power: A significant reduction in greenhouse gas emissions seems unlikely given our continued heavy reliance on fossil fuel consumption. Even UK environmentalist James Lovelock, who posited the Gaia theory that the Earth operates as a giant, self-regulating super-organism, now sees nuclear energy as key to our planet's future health. ''Civilization is in imminent danger,'' he warns, ``and has to use nuclear -- the one safe, available energy source -- or suffer the pain soon to be inflicted by our outraged planet.''

Yet environmental activists, notably Greenpeace and Friends of the Earth, continue lobbying against clean nuclear energy and for the Band-Aid Kyoto Treaty. Renewable energies, such as wind, geothermal and hydro are part of the solution. Nuclear energy is the only nongreenhouse gas-emitting power source that can effectively replace fossil fuels and satisfy global demand.

• Forestry: Activists tell us to stop cutting trees and to reduce our use of wood. Deforestation is caused by clearing forests for farms and cities. Forestry operations are geared toward reforestation and the maintenance of forest cover. Forests are stable and growing where people use the most wood and are diminishing where they use less. Using wood sends a signal to the marketplace to plant more trees and produce more wood. North Americans use more wood per capita than any other continent, yet there is about the same forest area in North America as there was 100 years ago.

Trees are the most abundant, renewable and biodegradable resource in the world. If we want to retain healthy forests, we should be growing more trees and using more wood, not less. This logic seems lost on activists who use chilling rhetoric and apocalyptic images to drive us in the wrong direction.

• Prognosis: Environmentalism has become anti-globalization and anti-industry. Activists have abandoned science in favor of sensationalism. Their zero-tolerance, fear-mongering campaigns would ultimately prevent a cure for Vitamin A deficiency blindness, increase pesticide use, increase heart disease, deplete wild salmon stocks, raise the cost and reduce the safety of healthcare, raise construction costs, deprive developing nations of clean electricity, stop renewable wind energy, block a solution to global warming and contribute to deforestation. How sick is that?

Patrick Moore is chairman and chief scientist of Greenspirit Strategies Ltd. in Vancouver, Canada.