What is the lowest intake suv on a pet scan(lung nodule)?

None: In general, any suv below 2.5 is considered not malignant, however one has to be careful as several factors affect suv, like the size of the lesion, also there is a lot of variability in suv among different machines and depends also on the dose injected.

Lung background: I think that you are asking what is the lowest suv value that a lung nodule could have? Or when is a lung nodule suspicious? We usually use the lung background as reference for lung nodules. Lung background is very low and often 1-.5 or below. If the metabolic activity on a nodule stands out as compared to background (e.g. Suv above background), follow-up pet/ct is recommended to ensure resolution.

Zero: The lowest suv (standardized uptake value - a semiquantitative measure of metabolism) is zero. The maximum suv in a region of interest is called suv max. Generally, if the lung nodule is less than an suv max of 1, it is likely benign. However, there are plenty of non malignant diseases that can have increased FDG uptake, such as healing fungal lung infections, called granulomas.