An MSDS is a Material Safety Data Sheet. They are required for products in the US and Canada that are used in the workplace. Many retail products do have MSDS’s available. I did a quick search. There were a number for Rain-X. I thought that this one would be the most appropriate.
http://www.pennzoil-quakerstate.com/techdata/msds/Display_MSDS.asp?ID=205754
This document indicates that it contains:
WATER, METHYL ALCOHOL, ISOPROPYL ALCOHOL, BUTYL CELLOSOLVE, SILOXANES AND SILICONES
The MSDS quotes the hazard as follows:
Ingestion: Do not ingest. Ingestion of large quantities may be harmful. Can cause central nervous system (CNS) depression if ingested. Can cause reversible or permanent blindness. Ingestion may result in lung aspiration. Aspiration may lead to chemical pneumonitis which is characterized by pulmonary edema and hemorrhage and may be fatal. Signs of lung involvement include increased respiratory rate, increased heart rate, and a bluish discoloration of the skin. Coughing, choking, and gagging are often noted at the time of aspiration.
This warning refers to the blend of ingredients in the product.
Assuming that the alcohol will evaporate off… there would be two ingredients remaining. One of those ingredients, Butyl Cellosolve, is most probably the main contributor.
Here is a reference for an MSDS for Butyl Cellosolve:
http://www.sciencestuff.com/msds/C1396.html
It contains the following warning:
DANGER!! This material is a hemolytic agent and prolonged exposure will cause liver and kidney damage. Effects of over exposure: headache,nausea,dizziness,vomiting,tears,temporary clouding of the eyes,shortness of breathe and irratition of the eyes,nose and throat. Acute: prolonged exposure will make the effects of over exposure more severe. Chronic: none are listed by manufacturer however, it is stated that this material has not been fully investigated. Target organs: eyes,liver, kidneys, and upper respiratory tract. Conditions aggravated/target organs. Persons with pre-existing eye,skin,liver,kidney or respiratory conditions may be more susceptible.
… I wouldn’t even give this to my boss !