One of the end products of disinfection with water with chlorine (or chlorine bleach) is chloroform. This is a known problem for waste treatment and water sources with high organic load. Chloroform has a high vapor pressure especially in the presence of water (forms an azeotrope at 53.3 =B0C, 128 F with 97% of chloroform in the gas phase).
In the absence of an experiment it is hard to guess the air concentration, but one has to wonder if it would be close to the STEL (60 min STEL = 2 ppm, PEL = 50 ppm or 240 mg/m =B3, TLV-TWA = 10 ppm, IDLH = 500 ppm, data from the NTP monograph). The STEL would probably apply to the public and the actors would probably fall under the TLV-TWA limit.
Chloroform is also easily absorbed from water through skin. In one study the blood concentration increased 2-7 fold after a shower (see the reference below).
A measurable concentration of chloroform (above TCLP = 6 mg/L) would also pose costly problem for disposal of the dye solution after the production. This cost should be included in the production budget.
There is also the issue of potential toxicity of other oxidation/chlorination products from the dyes and stabilizers. Depending on the particular dye there is a potential the formation of quinoid compounds. Some of them are associated with toxicity if ingested. I don't have data on transdermal absorption.
A similar issue has been reported with BHT, the popular preservative in plastics etc. The BHT itself appears quite safe, but its oxidation byproducts are potentially toxic.
Finding good data on the oxidation of dyes would require some search, but perhaps a conversation with a friendly toxicologist could give you some hints.
Nuckols JR, Ashley DL, Lyu C, Gordon S, Hinckley AF, Singer P. 2005. Influence of tap water quality and household water use activities on indoor air and internal dose levels of trihalomethanes. Environ Health Perspect 113(7): 863-870
If they are planning to disinfect first then heat, they might be asking for more trouble. The heat breaks down the disinfectants into corrosive chemicals. Here is an article about bromine:
However, since the chemistry of disinfection is the same with chlorine, I am assuming heating would generate chlorine and hydrochloric acid with a chlorine based disinfectant.
Recommendations for hot tub water is that it not exceed 104 =CB=9AF. First because it could burn bathers, but also, because the heat starts to break down the disinfectants at this temp.
I understand that the water will be at room temp when all of this takes place, but if they take the water up to 140 =CB=9AF in the presence of disinfectants, then pump it back into the "pool," the damage will have been done.
On Dec 1, 2012, at 8:23 AM, ACTSNYC**At_Symbol_Here**CS.COM wrote:
I'm adding that to a list of suggestions. I'm going to prepare for them information gleaned from these WONDERFUL e-mails. And also the information about why chlorine and bromine are not likely to work.
Now here's the NEW QUESTION: They are now planning to pump the 1500 gallons into he liquid for storage between shows into (6) 275 gal tanks. They are working on finding a heater that would rotate between the tanks and bring the stuff up to 140 o F each for a period of time.
Assuming they can "pasturize" the stuff, now we really need that chemist to look at the reactions of this soup at 90 ' F for the hours of the show and 140 o F periodically during storage. I can help with the dyes, but the the rest is a mystery.
In a message dated 11/30/2012 5:27:02 PM Eastern Standard Time, dmdecker**At_Symbol_Here**UCDAVIS.EDU writes:
Always astonishing what our dear theatre folks have in mind ....
Tagging off Kim's suggestion .... Rather than water, could they use strips or pieces of fabric that would give the illusion of a liquid? A tub (puddle?) full of fabric "confetti, " if you will, dyed to look like blood, might work. It wouldn't stick to the performers but it might be close enough.
Just a thought .....
Debbie M. Decker, CCHO
Campus Chemical Safety Officer
Environmental Health and Safety
University of California, Davis
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