A radio report this morning says a major recall of propane due to hydrogen sulphide contamination has been done for all propane sold in the past week in a small city and its surrounding area. Several searches have yielded no articles about it online yet. Any industry experts out there who care to hazard a guess as to whether or not the contamination could have been due to y2k testing?

-- Rachel Gibson (rgibson@hotmail.com), June 11, 1999

Answers

Why do folks want to blame every foul-up on Y2K? Computers may be great at duplicating fairly ordinary foul-ups tens of thousands of times a second, but the truly wierd ones usually require a human.

This is the second most bizarre product contamination I've ever heard of. The most bizarre was several hundred gallons of maple syrup being turned into industrial alcohol, because it had been contaminated with Tabasco sauce!

By the way, hydrogen sulphide will burn into fairly harmless sulphur dioxide, so the hazard would be breathing the propane unburnt. Hard to see how H2S poisoning from that could be a greater hazard than the probable propane explosion ... unless you're a substance abuser ... unless what they really mean is that there's no propane at all in the bottles...

-- Nigel Arnot (nra@maxwell.ph.kcl.ac.uk), June 11, 1999.

as in y2kPROpain, he,s a gas. && very contaminated.

-- al-d. (catt@zianet.com), June 11, 1999.

Nigel, Thank you for your thoughtful response.

More info now available from Canadian Press:

(For educational purposes only)

"RED DEER, Alberta -- Propane suppliers in central Alberta are scrambling to deal with a massive recall of poisonous propane distributed throughout the region.

About 100-thousand litres of propane contaminated with hydrogen sulphide was shipped by Western Facilities Management to retailers over the last week.

The gas was sold to industrial and residential consumers. The scare prompted the Alberta government to issue a public health advisory yesterday warning about the potential dangers of the contaminated propane.

Dr. Karen Grimsrud, Alberta's deputy provincial health officer, says people should not sniff their propane tanks to see they are contaminated.

She says at concentrated levels hydrogen sulphide is odourless and inhalation could result in respiratory paralysis.

The contaminated propane was sold at 16 retailers in central Alberta between May 29th and June 9th."

-- Rachel Gibson (rgibson@hotmail.com), June 11, 1999.

The remarks I saw about the toxicity of H2S and SO2 didn't sit quite right with me, so I looked in my old chem 201 text.

From "Chemistry and Chemical Reactivity," Kotz and Purcell, page 844:

BEGIN TEXT

Hydrogen sulfide, H2S, is the simplest hydrogen- containing compound of sulfur... However, unlike water, hydrogen sulfide is a gas under normal conditions...

Furthermore, hydrogen sulfide is a deadly poison, comparable to hydrogen cyanide. Fortunately, the sulfide has a terrible odor, and can be smelled in concentrations as low as 0.02 ppm. You must be careful with H2S, however, because it has an anesthetic effect on the olfactory nerve, so your nose can lose its ability to detect H2S. Death occurs at H2S concentrations of 100 ppm.

SULFUR-OXYGEN COMPOUNDS

At least thirteen oxides of sulfur are known to exist, but only the dioxide (SO2) and trioxide (SO3) are important. The former is produced on an enormous scale by the combustion of sulfur, by roasting sulfide ores (especially iron pyrites, FeS2) in air or by the combustion of sulfur-containing coal and fuel oil...

Sulfur dioxide is a colorless, toxic gas with a choking odor. It readily dissolves in water to give solution of a species that we write as H2SO3 (sulfurous acid...

The most important reaction of SO2 is its oxidation to the trioxide...

Sulfur trioxide is extremely reactive and is very difficult to handle; as described below, it is almost always deliberately converted to sulfuric acid by reaction with water.

END TEXT

So, unless you are willing to consider the authors of a college level Chemistry textbook wrong, that propane is deadly in more ways than just flammable or explosive.

-- LP (soldog@hotmail.com), June 12, 1999.

Nigel,

I posed the same question on the Bellingham explosion. Every time someone farts they blame it on Y2K. I'm all for Y2k awareness and preparation, but this is riduculous.

-- GeeGee (GeeGee@madtown.com), June 12, 1999.

Thanks for that detailed description of possibilities, LP. It took a while for the articles about it to come online, but one indicates that the government of Saskatchewan has also issued a warning, so it appears outlets other than the ones tallied in the article above also sold this substance.

-- Rachel Gibson (rgibson@hotmail.com), June 12, 1999.

Western Facilities says it does not know what caused the contamination. All its press release indicates is that: "The Nevis Gas Plant is currently closed for a scheduled maintenance turnaround and this incident is not expected to affect ongoing operations." With all due respect to you serious preparers who did not read/understand my original question, will we have the same checks and balances of corporate warnings/government health bulletins when/if contaminations occur in gas plants and chemical plants next year?

-- Rachel Gibson (rgibson@hotmail.com), June 12, 1999.

A "maintenance shutdown" is usually used to change cmoputer programs and control systems. If they were brought back on line incorrectly....but, it doesn't matter.

Again, look at the relationship to learn how fast and how far the impact was; and how wide that impact was; from only ONE mistake.

-- Robert A. Cook, PE (Kennesaw, GA) (cook.r@csaatl.com), June 12, 1999.