From first look, yes, and for more or less modern engines, which really don't need lead.
But for planes, normal age more than 20 years, even exist workhorses with 70 years.
They have very old engine technologies, some literally spread gas on ground (use lead in it to lubricate valves, which are outside, like on old star engines).
So even when you walking where such plane was, you will gather some lead.
