Right, should have said, "Nicotine sulfate". That's what I get for spouting before searching.

From the MSDS at http://www.sciencelab.com/xMSDS-Nicotine_Sulfate_40_in_aqueous_solution_-9926226

Section 11: Toxicological Information
Routes of Entry: Absorbed through skin. Eye contact. Ingestion.
Toxicity to Animals:
Acute oral toxicity (LD50): 125 mg/kg (Rat) (Calculated value for the mixture).
Acute dermal toxicity (LD50): 125 mg/kg (Rabbit) (Calculated value for the mixture).
Chronic Effects on Humans:
DEVELOPMENTAL TOXICITY: Classified Development toxin [POSSIBLE] [Nicotine Sulfate].
Contains material which may cause damage to the following organs: lungs, upper respiratory tract, central
nervous system (CNS).
Other Toxic Effects on Humans:
Hazardous in case of skin contact (irritant), of ingestion.
Slightly hazardous in case of eye contact (corrosive), of inhalation (lung irritant).
Non-permeator by skin. Non-hazardous in case of inhalation.
Special Remarks on Toxicity to Animals: Not available.
p. 4
Special Remarks on Chronic Effects on Humans: Not available.
Special Remarks on other Toxic Effects on Humans: Not available.
Section 12: Ecological Information
Ecotoxicity: Not available.
BOD5 and COD: Not available.
Products of Biodegradation:
Possibly hazardous short term degradation products are not likely. However, long term degradation products may
arise.
Toxicity of the Products of Biodegradation: The products of degradation are less toxic than the product itself.
Special Remarks on the Products of Biodegradation: Not available.
Section 13: Disposal Considerations
Waste Disposal:
Section 14: Transport Information
DOT Classification: CLASS 6.1: Poisonous material.
Identification: : Nicotine Sulfate, Solution (Nicotine Sulfate) UNNA: 1658 PG: II
Special Provisions for Transport: Not available.
Section 15: Other Regulatory Information
Federal and State Regulations:
Pennsylvania RTK: Nicotine Sulfate
Florida: Nicotine Sulfate
Massachusetts RTK: Nicotine Sulfate
New Jersey: Nicotine Sulfate
TSCA 8(b) inventory: Nicotine Sulfate; Water
TSCA 8(d) H and S data reporting: Nicotine Sulfate: June 1999
SARA 302/304/311/312 extremely hazardous substances: Nicotine Sulfate
CERCLA: Hazardous substances.: Nicotine Sulfate: 1 lbs. (0.4536 kg);
Other Regulations: OSHA: Hazardous by definition of Hazard Communication Standard (29 CFR 1910.1200).
Other Classifications:
WHMIS (Canada):
CLASS D-1A: Material causing immediate and serious toxic effects (VERY TOXIC).
CLASS D-2A: Material causing other toxic effects (VERY TOXIC).
DSCL (EEC):
R26/27/28- Very toxic by inhalation, in
contact with skin and if swallowed.
HMIS (U.S.A.):