Tuesday, June 26, 2012

Comment from the EPA

A comment published in ES&T from the U.S. Environmental Protection Agency (EPA) allowed us to elaborate on safety issues related to unused medications and their disposal/removal from the household as well as clarify some of our methods in our response.

-A comment on our published paper from Dr. Christian Daughton, representing the EPA: http://dx.doi.org/10.1021/es301975v

-Our response to this comment: http://dx.doi.org/10.1021/es302534a

Supporting Information - data tables and spreadsheet

The supporting information for our paper can be found at the following locations (free of charge):

-The supporting information file that contains more detailed information about the published study, including data tables for the emission values of each scenario, and talks through how the spreadsheet is setup and how to use it:  http://pubs.acs.org/doi/suppl/10.1021/es203987b
-The spreadsheet that contains all of the calculations:  http://deepblue.lib.umich.edu/handle/2027.42/91619

Thursday, May 24, 2012

FAQs

Below are some of the common questions we have been asked and our answers:


Isn't part of the point of take-backs to remove drugs from leaking into the environment through flushing or landfill leakage? Did your study address whether this is really a problem or not?
Yes it is a goal of take-back programs to reduce the amount of drugs that end up in the environment. And yes, our study did address whether this is a problem or not; the transport of unused medications to the environment via flushing and landfill was considered. Another point to make is that many of the pharmaceutical compounds that are found in the environment are expected to be from animal and human excretion, not from the disposal of unused medication. Given this point along with the increasing interest in and implementation of take-back programs in the U.S., our study shows that major efforts to take-back medications are not currently warranted environmentally.


People will now ask you what advice you give for disposing of drugs. What is your advice? Have you consulted with the DEA or environmental authorities about giving that advice?
For consumers, our recommendation is that people follow the FDA's guidelines for "Disposal in Household Trash".  Primarily, though, the advice we are giving is to those entities that are implementing and raising awareness about unused medication disposal (DEA, FDA, ONDCP). We are examining current practice and raising big questions about whether these programs are worth it.  Also, we are currently working on contacting these different organizations and fortunately several individuals at these organizations are already aware of this study. 


One of the goals of take-back is to reduce the storage (and the resulting risk of accidental poisoning, diversion, and abuse) of unused medications in the household. Will supporting trash disposal increase home storage? 
No. Based on:  (i) current disposal trends in the U.S. that show people favor trash disposal over storage, and (ii) current disposal trends in Sweden, where there has been a national take-back program for 40 years, show that only about 40% of people will take-back their medication while about 50% will store their unused medication instead of disposing of it at all.  Similar to battery disposal, it seems that more people will get rid of unused medications if they have a clear message and convenient disposal route, such as trash.


How did you handle making assumptions for this analysis?
Since all of the data needed to make these calculations is not known, and will possibly never be known (such as how many times a person will drive to the pharmacy to take-back medication in one year and how many trips will be combined with other errands), we conducted an uncertainty analysis. This analysis allowed us to report a large range of possible outcomes. Even with these large ranges the trends of environmental emissions are unaffected; take-back and trash have similar emissions of drugs to the environment and take-back has many more emissions of other pollutants (such as greenhouse gases) than trash disposal.

Did you look at the impact of the DEA's national take-back events that happen periodically?
No. We looked at the environmental emissions that would result from the national implementation of take-back, which would translate into pharmacies having that ability to take-back unused medications year round.


Why were you surprised that trash disposal turned out to be the best recommendation for disposal?There is a push for take-back (several pilot take-back programs in the U.S. and new U.S. federal legislation that supports national implementation of take-back). But, it turns out that our municipal solid waste system (for household trash), which is already in place and heavily used, is a good option based on environmental emissions, participation, and cost.

Sunday, May 13, 2012

Responses to Chemistry World Press

Regarding the Chemistry World Article “What to do with leftover prescription drugs?” (http://www.rsc.org/chemistryworld/News/2012/May/drug-waste-unused-medicine.asp), there were some issues with the article that led to some false tension between the authors and Michael Depledge. 

Professor Depledge rightly points out the issue of API/metabolite excretion and that this may be the real issue we should be concerned with.  I made this point as well in my interview with Hayley Birch, pointing out that only bringing “silver bullet” technology to Wastewater Treatment Plants (WWTPs) or reformulating medications as biologics could really solve both excretion and unused medication disposal problems.  This would also address the hotspot issue that Professor Depledge raises. 

It is also important to note that the authors agree that unused pharmaceuticals are not the first place to be concerned with when it comes to APIs in water – which further supports the main point of the paper that major efforts to take-back medications are not currently warranted environmentally.

Steve Skerlos

Monday, May 7, 2012

LCA on the Disposal of Unused Medications

The full research article that quantifies the environmental impacts associated with the disposal options for unused, unwanted, and expired medications can be found here in Environmental Science & Technology:  Life Cycle Comparison of Environmental Emissions from Three Disposal Options for Unused Pharmaceuticals.



Our research shows that the disposal of unused medications in the trash can provide consumers with the ability to immediately and conveniently remove medications from their households while resulting in similar environmental emissions of pharmaceutical compounds but significantly less emissions of other polluting substances, such as greenhouse gases, compared to "take-back" programs.

We are hoping that this blog will serve as a central location for the discussion of this study, both the research methods and the impacts of its results and conclusions.