We are aware that you have very small quantities of ethylene glycol solutions. If you are likely to repeat the activity and if the solutions are not contaminated, then you could suitably label and keep the solutions for the next time you conduct the activity.
Ethylene glycol is a scheduled poison and is classified as toxic1. Although the threat it poses to aquatic organisms is low,2 water authorities we contacted3,4 do not recommend that it be disposed of down the sink. One authority4 advises that the substance has a high biological/chemical oxygen demand and can therefore potentially affect waste water treatment processes4. Ethylene glycol has household and industrial applications as an antifreeze/coolant; manufacturers of the substance recommend that with respect to disposal, it is considered hazardous waste5,6.
Some options for disposal are:
- reuse as antifreeze;
- deposit it at a recycling collection point or alternatively, at a nearby automotive workshop which has the capacity to recycle it.
- contacting local waste facilities or the environmental protection agency for your state/territory7.
In the absence of these options, the ethylene glycol solution can be transferred to a labelled container and stored for collection by a licenced chemical waste disposal contractor8.
1 ChemSupply. 2014. Ethylene Glycol, Safety Data Sheet, ChemSupply website, https://www.chemsupply.com.au/documents/EA0071CH2S.pdf
2 Concise International Chemical Assessment Document 22 ETHYLENE GLYCOL: Environmental aspects http://www.inchem.org/documents/cicads/cicads/cicad_22.htm#PartNumber:1 (Accessed November 2017)
3 TasWater. 2017. Personal communication.
4 SA Water. 2017. Personal Communication.
5 Department of the Environment and Blue Environment Pty Ltd. 2015. Hazardous Waste in Australia, Australian Government Department of the Environment and Energy website, http://www.environment.gov.au/system/files/resources/9ae68d42-d52e-4b1d-... (Accessed November 2017)
6 ‘Hazardous waste’, Better Health Channel website, https://www.betterhealth.vic.gov.au/health/healthyliving/hazardous-waste... (August 2014)
7 ‘Household Chemical CleanOut’. NSW EPA Website. http://www.epa.nsw.gov.au/your-environment/recycling-and-reuse/household... (Accessed November 2017)
8Science ASSIST. 2017. Science ASSIST Chemical Management Handbook, Science ASSIST website, https://assist.asta.edu.au/resource/4193/chemical-management-handbook-au...