Wait until more is known???
You do realize Zinn's column was from 2005?
There's been 10 years of data collected since then. How much more do we need before some imaginary rash of asploding chains internet hoax is put to rest forever?
There has simply been no rash of chain breakage traced to spraying, hosing or soaking in Simple Green or ANY other cleaning agent since that blog. The purported 'Hydrogen Embrittlement' mentioned is both physically and chemically impossible.
There WAS a well known issue with SRAM chain breakage that was traced to the manufacturer. Simple Green, nor ANY other cleaner/degreaser had anything to do with that problem.
Frankly, short of using some percentage of concentrated acid or alkalis used to attack the steel...which WOULD result in readily identifiable micro-cracking, pitting, etching or surface treatment degradation. And there has been NONE of this reported.
I would have been the poster child for chain breakage 'if' cleaning a bicycle chain in Simple Green could somehow work an impossible chemical attack on the many chains I've cleaned with Simple Green. These include Sedis, Regina, Campagnolo...and yes...even my shitmaNO chain on the Emonda. Not the el cheapo Sedis...which is cheaply black oxided carbon steel...or the most expensive Campagnolo high Nickel plated chains were damaged in any way.
Looking at once-a-week and many times twice-a-week cleanings on multiple bikes over at least 10 years, I'm guessing I've performed well over 600 cleanings with Simple Green and have yet to die or sustain even a hangnail as the result of using that excellent product.
From the MSDS the active ingredients in Purple Power are:
INGREDIENTS: Water, Sodium Hydroxide, Sodium Metasilicate, 2-butoxyethanol, and surfacants
MANUFACTURER: Aiken Chemical Co., Inc., Greenville, SC
2- Butoxyethanol* 111-76-2 <8 25 ppm N/A
Sodium Metasilicate
Sodium Hydroxide 1344-09-8 1310-73-2 <5 <6 N/A 2 mg/m3 N/A N/A 25 ppm N
This product is destructive to eye tissues. Will cause burns that result in damage to the eyes and blindness if the solution remains in contact with the eye.
Swallowing will irritate throat, esophagus and digestive tract. Product may cause burns to mucous membranes of the mouth, throat, esophagus and stomach.
Airborne concentrations of mists/vapors may cause damage to the upper respiratory tract and even to lung tissue. If the product is heated, vapors are acutely toxic if inhaled.
From the MSDS the active ingredients in Simple Green are:
Water ≥ 78%
2‐butoxyethanol ≤ 5%
Ethoxylated Alcohol ≤ 5%
Tetrapotassium Pyrophosphate ≤ 5%
Sodium Citrate ≤ 5%
Fragrance Proprietary Mixture ≤ 1%
Colorant Proprietary Mixture ≤ 1%
NFPA/HMIS Rating:
Health = 1 = slight
Fire, Reactivity, and Special = 0 = minimal
Eye Contact: Mildly irritating.
Skin Contact: No adverse effects expected under typical use conditions. Prolonged exposure may cause dryness. Chemically sensitive individuals may experience mild irritation.
Ingestion: May cause stomach or intestinal irritation if swallowed.
Inhalation: No adverse effects expected under typical use conditions. Adequate ventilation should be present for prolonged usage in small enclosed areas.
If anything, the reactivity, toxicity and corrosive effects of Purple Power are greater than those of Simple Green. And despite the dire warnings on the Purple Power MSDS I highly doubt there has been one person in the entire United States hospitalized due to its use.
They give this stuff to housewives to clean with so I could be completely wrong on that! Please don't shoot me for qualifying my statement!