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This technology was disclosed to the U.S. Environmental Protection Agency in communications dated Sept. 17, 2001. A general news release and full public disclosure followed on Oct. 8, 2001.
The
information herein was revised Feb. 13, 2002 upon a finding that
the oral rat LD50 value for ethylene glycol is 8,300, not 4,700 mg/kg.
Abstract
It is estimated that approximately 4,500 humans are poisoned and 90,000 domestic animals plus countless wild animals die annually in the USA by ethylene glycol (EG) from products such as antifreeze. Ingested EG is not itself toxic until it becomes metabolized by the alcohol dehydrogenase (ADH) enzyme to glycoaldehyde and then metabolized further to other toxic metabolites. The inventors of the Evans De-Tox™ process have discovered that a practical and inexpensive substance, namely propylene glycol (PG), when mixed with EG, acts as an ADH enzyme inhibitor, preventing the metabolism of EG and preventing the toxic metabolites that are the essence of EG poisoning. The effectiveness of the method has been proven in a series of laboratory tests using Sprague-Dawley rats according to GLP test procedures in a facility certified by the EPA. The LD50 value of EG is 8,300 mg/kg. Mixtures of 50% EG/50% PG (by wt.) and 70% EG/30% PG (by wt.) are demonstrated to be so low in toxicity that LD50 values for them cannot be determined. The LD50 value for a mixture that is 95% EG/5% PG (by wt.) was experimentally found to be approximately 15,000 mg/kg, a figure that indicates a very low toxicity and that compares to the toxic LD50 value of 8,550 that would be predicted by using a standard industry formula. Poisonings by ingestion of products containing EG are preventable by simply including a modest percentage of PG in the mixture. This fact should be the subject of an EPA mandate.
Revision required
Evans Cooling Systems, Inc. was informed by letter dated February 7, 2002, from the American Chemistry Council (ACC), that the LD50 value for EG of 4,700 mg/kg, a value that has been published for years in numerous MSDS documents and published elsewhere by respected sources, including the NIOSH Registry of Toxic Effects of Chemical Substances (RTECS) is incorrect. Soon after the October 2001 disclosure by ECS of its DeTox™ technology, the ACC undertook the re-translation of the Russian language publication, written in the early 1980's, that has been the supposed source of the 4,700 mg/kg figure. Two significant errors were found in the original translation. First, the 4 and the 7 were transposed. The figure was 7,400, not 4,700. Compounding the first error was that the study results in ml/kg somehow became mg/kg in the literature. As the specific gravity for EG is about 1.120, the correct LD50 value for EG is 8,300 mg/kg. ECS is indebted to the ACC for taking the initiative to correct the LD50 information and bring it to ECS' attention.
The
basic thesis of the original disclosure remains. Tests that were performed,
however, using rats at dosages less than 8,300 mg/kg are recognized as irrelevant
and have been removed from the revised disclosure. Projections from tests performed
using rats at dosages less than 8,300 mg/kg are also removed. Based on the higher
LD50 value for rats against which ECS compares its experimental results, ECS'
current thinking is that EG poisoning can be prevented if a quantity of propylene
glycol (PG) equal to about 11 percent of the weight of the EG is mixed with
the EG. Previously, ECS had thought that about 5 percent would suffice.
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