Talk:Dimethyl carbonate

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1/15/2009 - I removed the claim that DMC is insoluble in water from the first sentence and indicated the aqueous solubility from Kowa's MSDS. The same solubility data is given in the first reference listed in the article: the reference is peer reviewed hence likely to be reasonably accurate. Plus, this is a very polar material, any chemist should know better than to claim H2O insolubility without strong evidence to back her/him up. It is also unusual in that it is a polar aprotic solvent, btw. —Preceding unsigned comment added by 63.81.122.66 (talk) 18:18, 15 January 2009 (UTC)

4/17/2009 - Dimethyl carbonate is a VOC exempt chemical

On January 13, 2009 the Environmental Protection Agnecy issued a final rule that no longer requires Dimethyl Carbonate to be regulated as a Volatile Organic compound for purposes of meeting the national ambient air quality standard for ozone under the Clean Air Act. The original petition to the EPA in 2004 by Kowa American to exempt DMC along with the full docket on information and comments leading up to this final rule can be found at: www.regulations.gov and accessing docket # EPA-HQ-OAR-2003-0948.

Dimethyl Carbonate was exempted as a VOC chemical because of its ultra low MIR (Maximum Incremental Reactivity)value of 0.06grams ozone / grams VOC and 5.4 grams of ozone / moles VOC were both below the EPA's benchmark of the MIR values for ethane (.31 and 9.3 respectively). A MIR value is a measure of a chemicals ability to produce ozone due to photochemical degradation, which was developed by Dr. William Carter. The lower the MIR value the less ozone is generated by that chemical to create smog.

This Federal VOC exemption for DMC allows it to be used immediately in most coatings to meet the national VOC rules found in 40 CFR part 59 for auto refinish coatings(subpart B), consumer products (subpart C), architectural coatings (subpart D) and aerosol coatings (subpart E). The federal government enforces these rules unlike most stationary source rules that are enforced by state governments. This exemption does not apply to states that have more stringent VOC rules than the federal government such as California and Northeast states in the NE ozone transport district as although the federal standards are met the state standards must rely on each individual state's definition of exempt VOC compounds for the more stricter state's rule.

For stationary sources of pollution (ie factories and repair shops that are regulated by a states implementaion plan, require that State to have added DMC to thier respective States VOC exemptlist. So far the following states have ALREADY approved DMC for use in their state Implementation plans: NH,PA,WV,NC,KY,CT,NJ,OH,MS,NM,MT,MN,MD,VT. Most other states besides California are planning to add DMC to their state's list of VOC exemptions to be in step with the federal definition, with implementation dates varying widely. Contacts for State regulators for air pollution compliance can be accessed at the NACAA webpage: www.4cleanair.org

Dimethyl Carbonate has a reccomended maximum exposure limit of 200 ppm (footnote 3)over 8 hours which based on methanol's TLV limit of 200 ppm. Dimethyl carbonate is expected to metabolized in the body to methanol, so general safety precautions warrant that exposure levels to DMC not exceed that of methanol. Although toxicity tests with animals show DMC to have a low toxicity profile, methanol is not as toxic to these test animals as to humans, so adhering to the 200 ppm recommended level would be prudent.

DMC has a light unobjectionable odor that has been referred to as methanol like or esterlike.

footnote 3 Kowa American MSDS dated January 21, 2009 (available at www.chemical.kowa.com)Rockwood33 (talk) 18:38, 17 April 2009 (UTC)