Chance of loss is in racetrack environs (4)
I believe the answer is:
risk
'chance of loss' is the definition.
'risk' can be an answer for 'chance' (I've seen this before). I am not sure about the 'of loss' bit.
'is in racetrack environs' is the wordplay.
'in' indicates putting letters inside.
'racetrack environs' becomes 'rk' (I can't explain this - if you can you should give a lot more credence to this answer).
'is' going inside 'rk' is 'RISK'.
Can you help me to learn more?
(Other definitions for risk that I've seen before include "Jeopardy" , "Take a chance" , "Gamble" , "The possibility of danger - chance it" , "Endanger, jeopardise" .)