Both hot and cold smoked salmon are usually chilled and consumed within 10 days, or they are subsequently frozen. Unless you are considering storing them unchilled or for longer periods of time without freezing then the use of Cure #1 is not required. You may want to add it though if you are uncertain as to the provenance of the fish (in which case do not eat it) or is a variety that is more susceptible to having botulinum in their intestines or gills (usually more prevalent in bottom dwelling muddy river or lake fish).
Botulism as a result of eating fish is rare. The last recorded outbreak in the UK was in 1955 and was as a result of eating pickled imported fish. I do not have figures for the USA though - it may be more common there. The table below from the Food and Agriculture Organization of the United Nations shows laboratory results of different types of fish that were each inoculated with one million botulinum organisms (which is far higher than is found naturally occurring in fish) and the number of days that it took before they became potentially toxic at different temperatures.
Fish product
|
Temperature of storage
| | |
|
5°C
|
10°C
|
20°C
|
Herring
|
11
|
5
|
1
|
Cod
| |
10
| |
Plaice
| |
10
| |
Scallops
| | |
6
|
Kippers
| |
9
|
2
|
Smoked salmon
| |
18
|
7
|
Smoked trout
| |
11
|
5
|
Smoked haddock
| |
29
|
3
|
Even if you were to store it at room temperature (say 20 C (68 F)) it would still take at least 7 days before the botulinum toxic became potentially toxic. At higher temperatures this would be less, but I am sorry I don't have any figures to show how long it may take if left in your backpack while you are hiking around Furnace Creek in 46 C (115 F).
Providing you keep your smoked salmon chilled and eat it within 10 days (or freeze it for longer term storage) then there is no need to use nitrite in your cure. Of course, if you do it will not hurt you either - providing it is within safe limits.