There's no guarantee that they can't pick it up after a month, and if you lied on the application about smoking, it will go into your record at the Medical Information Bureau (M.I.B.) about the application being declined - and every life insurance company will be able to see that information.
That's one reason you shouldn't lie on the application for life insurance coverage. Another reason is because they can turn down a claim for life insurance if you die as a result of a lie you told on the application., if they catch it within the first 2 years of you being insured by the policy.
However, there are life insurance plans that do not require you to take a physical exam, blood or urine tests. These plans may ask you some health questions, and, if approved, you may even be able to start your life insurance coverage the same day.
Here's how you can learn more about the life insurance blood test and life insurance with no blood test required.