Coughing, congestion from plastic toy/containers?

My six year old is lego obsessed.  We have a giant under bed plastic storage container full of legos.  It is usually downstairs in the living room, but it spent the night in his bedroom for a few nights. These same nights he was coughing and woke up with a head full of snot.  I don't even know why, but i though, hmm, he started coughing the same time as the lego box moved into his room.  Last night I removed the lego box from his room.  No coughing, no head full of snot this morning!

I don't know much about a plastic allergy, i know some people react to it with skin rashes, but is there something in plastic that causes respiratory issues as well?  Our house is full of plastic toys.  The box is # 5 plastic, not sure what the legos are made of.

thanks in advance for any insight!
jenna pepper of http://foodwithkidappeal.blogspot.com/
growing good eaters one bite at a time.

[Dr Rajput]

Hi, welcome to the forum, little is known about the plastics causing allergy, but can be a possibility. Also you need to find any other objects which he may be allergic to. As it evident from the history that plastic can be probable cause for allergic rhinitis. It may be a plastic or paint and other materials on the plastic releasing particles i.e. probable allergen.  If so is the case, avoid further exposure to such plastics.  I suggest you to consult pediatrician if there is recurrence. Take care and regards.