Re-posted from Huffington Post)

I became an environmental activist in the early 1970s just as I was completing my doctorate in ecology at the University of British Columbia. It was the height of the Cold War and the height of the Viet Nam War and we were compelled to take a very public stand against activities we thought to be catastrophic both for people and for the planet.

I joined a small committee that was meeting in the basement of the Unitarian Church. We organized a protest voyage against U.S. hydrogen bomb testing in Alaska and had tens of thousands marching in the streets. When that H-bomb was set off at Amchitka Island in November 1971, it was the last hydrogen bomb the U.S. ever detonated.

It was the birth of Greenpeace, the organization I co-founded, spending 15 years in its top committee, helping to lead environmental campaigns around the world.

But it’s ironic in the extreme that, as we mark the 100th anniversary of drinking water chlorination, my old organization and other activist groups aligned with it continue to oppose this most important public health achievement.  

Activist organizations like Greenpeace have access to a full century of observations on the results of water chlorination in the US, all the way back to September 26, 1908 when Jersey City, NJ became the first US city to chlorinate its public water supply.

It’s true, there were those back then who vehemently opposed the use of this “poison” in public water supplies. According to one official at the time, continued chlorination to eradicate typhoid was akin to being “between the devil and the deep blue sea, for at present we don’t know whether typhoid fever or the (chlorinated) drinking water is the worst.”

Thankfully from the perspective of human health, chlorination of water supplies spread rapidly. Today, chlorination is the overwhelming choice for treating public water systems.

The results are clear. This widespread adoption of chlorine disinfection across the U.S. has had very important results. Waterborne diseases like typhoid, Hepatitis A and cholera that once killed thousands of Americans each year have been virtually eliminated. Typhoid fever cases fell by more than 99 percent between 1900 and 1960. Related childhood mortality fell dramatically. And average life expectancy rose from 47 years in 1900 to nearly 78 years in 2006.

Yet, many of my old environmental colleagues continue to vilify chlorination of water by raising unwarranted fears about health risks of chlorine and disinfection byproducts. In fact, it was a Greenpeace decision in 1986 to support a world-wide ban on all chlorine use that turned out to be a breaking point between my old organization and me.

My strongly held view is that chlorine is essential for our health. It is that simple. At the time I explained to my fellow Greenpeace International directors that water chlorination was the biggest advance in the history of public health, and in addition that the majority of our pharmaceuticals are based on chlorine chemistry. As the only board member with an education in science, my words fell on deaf ears.

In short, my former colleagues ignored science and supported the ban, giving me no choice but to leave the group as I could not support such a policy. Despite science concluding no known health risks – and ample benefits – from water chlorination, Greenpeace and other environmental groups have continued to oppose its use for more than 20 years.

I believe the opposition to the use of chemicals such as chlorine is part of a broader hostility to the use of chemicals in general. I often cite Rachel Carson’s 1962 book, Silent Spring, as having had a significant impact on many pioneers of the green movement. The book raised some legitimate concerns, many rooted in science, about the risks and negative environmental impact associated with the indiscriminate use of chemicals.

But the day-to-day water chlorination that occurs across America is not in the category of indiscriminate use. For Greenpeace and groups like it, the healthy skepticism learned from Carson has hardened over the years, and given way to a mindset that treats virtually all use of chemicals with suspicion.

After a century of use and the resulting eradication of waterborne diseases across the US and the world, those activists who continue, absurdly, to oppose water chlorination only illustrate the need for an alternative environmental policy based on science and logic – not misinformation and campaigns of fear.

After all, campaigns based on groundless fears distract the public from real environmental threats such as air pollution and tropical deforestation for example.

As we mark one of the key milestones in improving the public health of Americans right across the country, let’s always remember we all have a responsibility to be environmental stewards. But stewardship requires that science drive our public policy, just as it did a hundred years ago in Jersey City.