There are some general points that need to be made about this question, and some will not directly answer your question. They may, hopefully be useful for future generations of home-chemists seeking answers on this site.
Firstly, all of these very practical questions should have been asked well before you carried out this process. Hindsight is a wonderful gift. Prior to any chemical handling process, all industrial and research chemists will carry out an extensive Hazard Identification and Risk Assessment. Prior to taking possession of this chemical you should be aware of how to store, handle and dispose of your chemicals. Disposal management includes spill control and safe disposal of unwanted waste materials.
Secondly, spilling some material on yourself during cleanup indicates that you were not sufficiently protected. Gloves, glasses, labcoats and other protective equipment need to be used during cleanup as well. Accidents can happen at any stage, and you need to be prepared for this.
Thirdly, if you are using a hazardous chemical in an environment where you can so readily smell it suggests to me that you have inadequate ventilation in your work area. You should address this immediately.
Finally, the first Risk Control measure the home chemist (any chemist!) needs to consider is subsitution. Is this really the only suitable reagent for you to use, or can you substitute it for another, less harmful, chemical?
Cyclohexylamine is a nasty chemical. It has a GHS signal word DANGER, which should immediately make any handler seek further information prior to using it. It is classed as
- Category 3 flammable liquid,
- Category 2 Oral Acute Toxicity,
- Cat 3 Dermal Acute Toxicity,
- Cat 1 Skin corrosion,
- Cat 1 Serious Eye Damage and
- Cat 2 Reproductive Toxicity.
Yes, Cyclohexylamine is a nasty chemical. Now, on to your questions.......
"as long as I don't feel irritation of my lungs or eyes, am I safe?"
No, no, no, good god, no. You will be subject to the dangerous effects of any chemical as long as you are exposed to them. Many effects will not be instantaneous; many can take hours or days (or even weeks) to manifest symptoms. I recall a case in the mid-90's, as an example, where a postgrad student died after cleaning up a spill of acrylonitrile in a lab. Symptoms of distress only became apparent several hours after the incident, and the person was hospitalized and died within 24 hours. Acrylonitrile essentially dissolves the tissues of the lungs. Not a nice way to die. Your lungs and eyes are the most sensitive areas of your body, and are likely to show irritation first. Consider, however, that your skin (especially your face) may have a much greater area of exposure, and this may be a pathway for contamination.
The PAC guidelines you ask about relate to extended periods of exposure. It does not mean that if you inhale 30ppm of a particular chemical you will experience life-threatening health effects immediately. Perhaps a more relevant and practical exposure guide is the Acute Exposure Guideline Levels (listed in your first reference), which shows that extended exposure at 30ppm for an hour could lead to life-threatening health effects or death. Or 10 minutes at 38ppm. The take home message from this is that if you can smell it, you are working in a dangerous environment.
"I accidentally touched a drop of cyclohexylamine (from the pipette) when I was cleaning up, with no gloves on".
Clearly, your previous statement "Of course I'm wearing a lab coat, safety goggles and chemical resistant gloves" was not quite correct. Personal safety equipment should be the first thing to go on, and the last thing to come off. I hope you treated the exposed area according to the MSDS first aid advice. Like other adverse chemical affects, corrosive properties do not need to be instantaneous. They can take a long time to manifest symptoms; HF, for instance, does not produce inflammation or burns until many hours after exposure.
"I still haven't figured out if I can pour the diluted mixture of water and cyclohexylamine down the drain, without poisoning myself or the neighborhood."
Many SDS do not explicitly describe safe disposal considerations, and you should probably seek a more comprehensive source. Chemical suppliers should now be moving toward the GHS system for chemical management, and the SDS from these companies should include (albeit brief and generic) disposal considerations. However, this is a chemical which is toxic to the environment and should be disposed of correctly. Most local Council or Municipal Waste Management Facilities will have chemical collection days, or specific chemical drop-off centres to receive these types of items. Speak to your local government authority, and seek advice from them. Occasionally, for some chemicals, you can return any unused portions to the place of sale. Normally, these types of chemicals are burnt in a chemical incinerator with afterburner and scrubber. You should collect waste mixtures in an appropriate container and store safely until ready for disposal. For small volumes of waste, you may consider using the spill control guidelines, which may offer a more practical approach to providing a safer chemical to store and dispose of.
