Yes, any petroleum compound can release fumes that are toxic within an enclosed space. These hydrocarbons have vapors that are heavier than air and can collect in a low or enclosed area. The vapors will displace the oxygen in the air and create an atmosphere that is oxygen-deficient.
Toxic symptoms can range from eye and respiratory irritation to severe inflammation and chemical burning within the lungs.
http://primis.phmsa.dot.gov/comm/FactSheets/FSProductList.htm -see under distillate fuels