You can draw your own conclusions from the 2 stories below. Apparently though, if done outdoors, it wouldnt be fatal. However, it does seem that shredding is better avoided.
A woman employed a contract gardener to remove a tree. He used a chipper to deal with the smaller branches. She asked him to also prune a run of cherry laurel and he said he would but he wouldn’t chip it having, on a previous occasion, almost passed out from the cyanide fumes coming off the chipper.
A tree surgeon talked about smelling almonds when he opened a van full of laurel shreddings.
But, the story of someone passing out while driving a van full of laurel prunings seems to be apocryphal. I have spoken to people who noted the smell associated with cyanide when using a chipper but, since this is an activity performed in the open air, the chances of becoming unwell seem small.
http://www.thepoisongarden.co.uk/atoz/p ... erasus.htm