Ethylene Glycol (eg) or Propylene Glycol (pg)

Do glycol recycling programs result in a significant increase in dissolved oxygen (DO) levels in surrounding storm water runoffs, due to the reduction of bio-degradation of ethylene glycol (EG) and propylene glycol (PG)?

Research Prospectus

Research Problem

Aircraft deicing fluids are typically composed of either ethylene glycol (EG) or propylene glycol (PG). The glycol main ingredient is mixed with thickening agents, wetting agents, corrosion inhibitors, and colored dye for identification. Propylene Glycol has become more common due to the fact it is less toxic than EG.

The primary source of EG in the environment is still run-off at airports. EG in air will break down in about 10 days. EG in soil and water will break down in several days to a few weeks. EG is moderately toxic in humans and ingestion by humans or animals can result in death. When ingested, it first affects the central nervous system, then the heart, and finally the kidneys. Reproductive health has also been shown to be at risk when humans are subject to EG vapors in large concentrations.

While PG has a low toxicity level in humans, it is known to exert high levels of biochemical oxygen demand while breaking down in surface waters. This can deplete dissolved oxygen aquatic life needs to survive. Runoff from typical concentrations of PG deicing fluid can have biochemical oxygen demands 2,500 times higher than raw sewage. Depending on airport size and the amount of deicing/anti-icing required, it is possible for thousands of gallons of deicing/anti-icing fluid runoff to make its way into surrounding waters. (Dave)

Assumptions

Stating glycol has a less than perfect track record in terms of safety would be an understatement. History has shown the adverse effects of Ethylene glycol on humans and other life forms have been more than evident. Therefore Polyethylene glycol or any derivative should be approached with great caution.

It will be assumed that the introduction of Polyethylene glycol beyond minimal levels in the environment will spawn adverse effects in aquatic ecosystems. There is creditable literature linking the addition of (PE)glycol in ecosystems resulting in an increase of O2. The speculation lies in connecting these increased O2 levels with ecosystem health. Constructing a link between these two variables will foster much criticism.

-Note (Ryan) this is only a draft any input on compressing or expanding it would be helpful (I didn't want to overlap others answers), also any problems with it's facts or readability. Thank you (Ryan)

Theoretical Issues

This paper will analyze existing data of the concentrations of various pollutants and O2 in runoff areas surrounding three major