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U.S. Department of Transportation U.S. Department of Transportation Icon United States Department of Transportation United States Department of Transportation

Interpretation Response #11-0070 ([DS Environmental Solutions] [Mr. Ricardo Guerra])

Below is the interpretation response detail and a list of regulations sections applicable to this response.

Interpretation Response Details

Response Publish Date:

Company Name: DS Environmental Solutions

Individual Name: Mr. Ricardo Guerra

Country: PR

View the Interpretation Document

Response text:

April 21, 2011



Mr. Ricardo Guerra

DS Environmental Solutions

Floral Park

62 Gautier Benitez

San Juan, PR 00917

Ref. No. 11-0070

Dear Mr. Guerra:

This responds to your December 21, 2010 letter and follow-up emails requesting clarification of the Hazardous Materials Regulations (HMR; 49 CFR Parts 171-180). Specifically, you inquire as to the applicability of the HMR to shipments of scrap dental amalgam. According to your letter, the material that you intend to ship is dental amalgam that is not derived from the medical treatment of humans, in that it has not been in contact with a patient; rather, it is the excess amalgam that remains unused in a dental filling procedure. You indicate that the amalgam contains approximately 50% mercury and 50% metal alloy, which is comprised of silver, copper and tin. You further state that you intend to ship approximately 6 ounces of amalgam at a time. You ask several questions regarding the classification of the scrap dental amalgam. Your questions are paraphrased and answered as follows:

Q1. Is the scrap amalgam considered to be regulated medical waste?

A1. Under § 173.22, it is the shipper's responsibility to properly classify and describe a hazardous material. This office does not normally perform that function. However, provided the amalgam does not come in contact with a patient or bodily fluids, it is not considered a regulated medical waste as defined in § 173.134 of the HMR.

Q2. Is the scrap amalgam considered a hazardous waste?

A2. The U.S. Environmental Protection Agency (EPA) and implementing states regulate the collection and management of certain widely generated wastes, such as mercury-containing equipment, as a universal waste. Certain states include dental amalgam waste as a universal waste. Universal waste is not subject to the Hazardous Waste Manifest Requirements specified in 40 CFR part 262 and thus, is not a hazardous waste as defined in the HMR (see § 171.8).

EPA Region 2 oversees the universal waste program for Puerto Rico. For more information regarding EPA universal waste regulations as they apply to dental amalgam, please contact the EPA Region 2 Division of Environmental Planning and Protection (DEPP) at 877-251-4575.

Q3. May we use the Unites States Postal Service (USPS), UPS or FedEx to ship the scrap amalgam?

A3. As we explain in A1, under § 173.22, it is the shipper's responsibility to properly classify and describe a hazardous material. However, it is our understanding that corrosive characteristics typically associated with liquid mercury are neutralized during the formation of amalgam. Therefore, given that amalgam does not meet the one pound RQ for mercury and does not meet any of the criteria of a hazardous material specified in § 171.8, it would not be subject to the HMR.

If you choose to transport the material using a common carrier, you should contact that carrier directly to determine if the carrier will transport the material. Postal shipments are under the jurisdiction of the USPS. Shipments of hazardous materials by the USPS are governed by 39 CFR Part 124, Domestic Mail Manual, U.S. Postal Service Regulations. For more information regarding the USPS hazardous materials regulations, you may call Mary Collins at


Q4. Do we need a permit issued by PHMSA to transport the scrap amalgam?

A4. No. See A3.

I hope this information is helpful. If you have further questions, please contact this office at (202) 366-8553.


Ben Supko

Acting Chief, Standards Development Branch

Standards and Rulemaking Division

173.22, 171.8

Regulation Sections

Section Subject
173.22 Shipper's responsibility