Broad beans with curling leaves

[bazzaboy]

My allotment neighbour's broad beans are producing leaves that appear to a) slightly blister (photo 2) and then b) curl up tightly (photo 1). No sign of aphids, K is worried it might be chemical damage (aminopyralid) in this year's farmyard manure. Are these typical symptoms or what else could it be?

[zazen999]

Definitely looks like it to me. Sorry.