In the past urethane has been produced commercially in the United States for well over 30 years. It has been used as an antineoplastic agent and for other medicinal purposes. It saw relatively heavy use in the treatment of multiple myeloma before it was found to be toxic and largely ineffective.[1] By US FDA regulations urethane has been withdrawn from pharmaceutical use. Urethane is not acutely toxic to humans, as shown by its use as a medicine. Acute toxicity studies show that the lowest fatal dose in rats, mice, and rabbits equals 1.2 grams/kg. or more. When urethane was used medicinally, about 50 percent of the patients exhibited nausea and vomiting, and long time use led to gastroenteric hemorrhages (USEPA 1979). The compound has almost no odor and a cooling, saline, bitter taste (HSDB 2006a).
Urethane is not acutely toxic to humans, as shown by its use as a medicine. Acute toxicity studies show that the lowest fatal dose in rats, mice, and rabbits equals 1.2 grams/kg. or more. When urethane was used medicinally, about 50 percent of the patients exhibited nausea and vomiting, and long time use led to gastroenteric hemorrhages (USEPA 1979). The compound has almost no odor and a cooling, saline, bitter taste (HSDB 2006a).
Studies with rats, mice, and hamsters has shown that urethane will cause cancer when it is administered orally, injected, or applied to the skin, but no adequate studies of urethane-caused cancer in humans has been reported (IARC,1974). The International Agency for Research on Cancer has stated that urethane can be “reasonably anticipated to be a human carcinogen based on sufficient evidence of carcinogenicity in experimental animals.” (NTP 2005). This evaluation has led to the following US regulatory actions:
NESHAP: Listed as a Hazardous Air Pollutant (HAP) Comprehensive Environmental Response, Compensation, and Liability Act: Reportable Quantity (RQ) = 100 lb Emergency Planning and Community Right-To-Know Act, EPA’s Toxics Release Inventory: A listed substance subject to RCRA reporting requirements RCRA Listed Hazardous Waste: substance - U238
I'm not sure we want that on our roofs, now do we?
Let me preface this by saying that I know pretty close to jack about chemistry, and surely about what's in this plastic dirt. And so do you.
What I can tell you is that "made from urethane" does not equate with "is urethane." The majority (all?) of non-recycled plastics are made from petroleum, but you wouldn't think of drinking from a soda bottle as getting oil in your mouth, would you?
When you take one urethane and put it with a bunch of others, you get polyurethane. If you don't want it on your roof, you surely don't want it on your furniture and especially not your dining room table, you know, the one you eat off of, so likely you'll want to get rid of that, because there's a very good chance it's got some kind of plastic sealant on it. And if not your dining room table, you surely have SOME furniture that's made shiny thanks to polyurethane.
My point is, plastic dirt COULD be carcinogenic, but it seems to me that your objection to the dirt, if based on the evidence you posted, is a pretty big leap. It sounds to me largely like an emotional reaction to an unfamiliar substance that's maybe not as unfamiliar as you think.
What you REALLY need to be worrying about is dihydrogen monoxide. That stuff is a major element of acid rain, it's found in almost all foods and every single ocean, river and lake on earth...but no government in the world will consider banning it. Stick it to the man!!!
The whole line-up consists of the $60 Amps in-ears and $100 Tracks on-ear headphones, which both also come in slightly souped-up and pricier HD variations at $100 and $130, respectively.
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This is what wikipedia has to say about urethane
In the past urethane has been produced commercially in the United States for well over 30 years. It has been used as an antineoplastic agent and for other medicinal purposes. It saw relatively heavy use in the treatment of multiple myeloma before it was found to be toxic and largely ineffective.[1] By US FDA regulations urethane has been withdrawn from pharmaceutical use. Urethane is not acutely toxic to humans, as shown by its use as a medicine. Acute toxicity studies show that the lowest fatal dose in rats, mice, and rabbits equals 1.2 grams/kg. or more. When urethane was used medicinally, about 50 percent of the patients exhibited nausea and vomiting, and long time use led to gastroenteric hemorrhages (USEPA 1979). The compound has almost no odor and a cooling, saline, bitter taste (HSDB 2006a).
Urethane is not acutely toxic to humans, as shown by its use as a medicine. Acute toxicity studies show that the lowest fatal dose in rats, mice, and rabbits equals 1.2 grams/kg. or more. When urethane was used medicinally, about 50 percent of the patients exhibited nausea and vomiting, and long time use led to gastroenteric hemorrhages (USEPA 1979). The compound has almost no odor and a cooling, saline, bitter taste (HSDB 2006a).
Studies with rats, mice, and hamsters has shown that urethane will cause cancer when it is administered orally, injected, or applied to the skin, but no adequate studies of urethane-caused cancer in humans has been reported (IARC,1974). The International Agency for Research on Cancer has stated that urethane can be “reasonably anticipated to be a human carcinogen based on sufficient evidence of carcinogenicity in experimental animals.” (NTP 2005). This evaluation has led to the following US regulatory actions:
NESHAP: Listed as a Hazardous Air Pollutant (HAP)
Comprehensive Environmental Response, Compensation, and Liability Act: Reportable Quantity (RQ) = 100 lb
Emergency Planning and Community Right-To-Know Act, EPA’s Toxics Release Inventory: A listed substance subject to RCRA reporting requirements
RCRA Listed Hazardous Waste: substance - U238
I'm not sure we want that on our roofs, now do we?
@Niels:
Let me preface this by saying that I know pretty close to jack about chemistry, and surely about what's in this plastic dirt. And so do you.
What I can tell you is that "made from urethane" does not equate with "is urethane." The majority (all?) of non-recycled plastics are made from petroleum, but you wouldn't think of drinking from a soda bottle as getting oil in your mouth, would you?
When you take one urethane and put it with a bunch of others, you get polyurethane. If you don't want it on your roof, you surely don't want it on your furniture and especially not your dining room table, you know, the one you eat off of, so likely you'll want to get rid of that, because there's a very good chance it's got some kind of plastic sealant on it. And if not your dining room table, you surely have SOME furniture that's made shiny thanks to polyurethane.
My point is, plastic dirt COULD be carcinogenic, but it seems to me that your objection to the dirt, if based on the evidence you posted, is a pretty big leap. It sounds to me largely like an emotional reaction to an unfamiliar substance that's maybe not as unfamiliar as you think.
What you REALLY need to be worrying about is dihydrogen monoxide. That stuff is a major element of acid rain, it's found in almost all foods and every single ocean, river and lake on earth...but no government in the world will consider banning it. Stick it to the man!!!