Forum, Aug. 7: The Dose Makes the Poison

Monday, August 06, 2018
The Dose Makes the Poison

I am writing in response to the report that polyfluorinated alkyl substances, known as PFAS, are present in the drinking water at two Vermont elementary schools at levels slightly above the state standard of 20 parts per trillion (“Vt. Schools Inspected for Chemicals,” July 31).

Astute readers will recognize that this level is equivalent to 0.02 ppb (parts per billion) or 0.00002 ppm (parts per million), which are the more commonly used descriptors for assessing concentrations of chemical contaminants. I point this out because very few chemicals are toxic at levels of parts per trillion (some examples are botulinus toxin, cobra venom, and perhaps plutonium).

As my chemistry colleagues continue to improve analytical methods, it is inevitable that we will find myriad chemicals — presently undetectable — in our water and food at levels of parts per quadrillion and even parts per quintillion. Readers also should know that molecules are unimaginably tiny. For example, a single drop of water contains 1,000,000,000,000,000,000,000 molecules of “dihydrogen monoxide” (water), a number that has been estimated to be equal to the number of grains of sand on all the beaches on earth.

How small is a part per trillion? One coconut in a row of coconuts to the sun; one penny in $10 billion; one drop of vermouth in 16 million gallons of gin (a very dry martini!); one second in 33,000 years.

I certainly do not belittle the fact that potentially toxic PFAS are present in drinking water in any amount, but given the current science on these chemicals, I do not believe that these extraordinary low levels pose adverse health effects, even to children. Readers need to realize that any chemical can be toxic, depending on the dose and manner of absorption. As Paracelsus said in the 16th century: “All things are poison and nothing is without poison. It is the dose only that makes a thing not a poison.”

Dr. Gordon W. Gribble


The writer is an emeritus professor of organic chemistry at Dartmouth College.

Hallquist Is the Best Choice for Vt.

If you plan to vote in the Democratic primary on Aug. 14, I urge you to vote for Christine Hallquist as the party’s candidate for governor of Vermont.

In 2005 Hallquist became CEO of Vermont Electric Cooperative, Vermont’s largest locally owned utility. Near bankruptcy then, the utility now has achieved a top bond rating without increasing rates. It is nationally recognized for adopting modern energy technology and providing 96 percent carbon-free electricity.

While government is not a business, much of it ought to be run in a businesslike way. At the same time, a governor must be politically astute to get things done.

Vermont Electric Cooperative is owned by its customers, so the CEO cannot dictate its direction heedless of often starkly differing opinions among its membership. Hallquist’s experience as the co-op’s leader has thus provided her with grass-roots experience in the politics of governance, as well as a solid grounding in prudent business management.

Christine Hallquist is your best choice for Vermont’s next governor.

Richard Andrews

Springfield, Vt.

Nuclear Power Is Safe, Not Perfect

The report by the three students from the Fukushima area (“At Dartmouth, Japanese Students Update on Fukushima Disaster,” July 28) is good news to those who believe nuclear power is part of the solution to our climate and energy problems, and bad news to those who oppose nuclear power and claimed the area would be unusable “forever.”

The tsunami of 2011 affected the Fukushima Daiichi site, where units 1, 2 and 3 had meltdowns. Those units and unit 4 had hydrogen explosions. Prompt actions of the operators, coupled with better site design, prevented reactor damage. But the tsunami flooded the basements and wiped out the electric power distribution system, causing reactor loss of cooling and leading to meltdowns.

The meltdown heat caused pressure in the containments (the same as Vermont Yankee’s) to far exceed the design, leading to leakage after about a day, many hours after an evacuation had been ordered. The leakage had radioactive particles and gasses from the meltdowns and hydrogen from the chemical reaction between water and hot metal. The hydrogen exploded in units 1-4, having leaked to Unit 4’s reactor building, where all the fuel had been removed from the reactor for maintenance. The unit 4 fuel pool was of immediate concern because freshly used fuel generates the most heat. Claims that a nuclear explosion had happened in the pool were proven wrong a few years later when all the fuel in the unit 4 pool was moved to the common site pool, undamaged.

Nuclear power was advertised as safe, not perfect.

Howard Shaffer


Trump’s Hypocrisy in Attacks on Iran

In recent verbal attacks on Iran, President Donald Trump is once again displaying his full command of hypocrisy. The Iranian leaders are charged with lining their pockets at the expense of the Iranian people and behaving like the “Mafia.” Yet the president has nothing to say about Russian President Vladimir Putin and North Korean leader Kim Jong Un, who make the Iranian leaders’ alleged crimes appear to be penny ante. And remember, Trump is in open violation of the Constitution’s emoluments clause, protected by the servile and spineless GOP in Congress.

There are many real, outstanding issues with Iran — most of which are, in fact, the result of U.S. geopolitical clodhopping. The best way to work toward resolution of these issues is start looking at them in their historical-political context, not with the pot calling the kettle black.

Mark R. Allen


Taking a Knee ... at Church

I find it fascinating that different gestures mean different things to different groups. The differences seem to depend on circumstances.

In my church, there is much standing and sitting. During Mass we sit for the readings, stand for the Gospel and the Lord’s Prayer, and for the prayers for the dead. We sit for the homily. However, we kneel at the Consecration. On arriving at the pew we kneel for a moment “on one knee.” This is called genuflection.

Do these gestures not remind one of a certain recent controversy? What about those NFL players?

Bob Cattabriga

West Lebanon