I bet Bt is not the only chemical in GMO foods causing toxic skin and respiratory problems in at least some people. I have noticed some new people mentioning reddened skin as one of their symptoms and in the past there has been some discussion of face swelling too.:
Article : POINT OF VIEW: Genetically Modified Foods Unsafe? Evidence that Links GM Foods to Allergic Responses Mounts Genetic Engineering & Biotechnology News - Biotechnology from Bench to Business
"The consistency between the reactions related to Bt sprays and those reported by Bt-cotton workers is astounding. The Bt spray was associated with sneezing, runny nose, watery eyes, skin inflammation and irritation, rashes, itching and burning, swelling, red skin and eyes, exacerbations of asthma, facial swelling, and fever. Some people required hospitalization.23,24 Bt-cotton workers in India reported sneezing, runny nose, watery eyes,
skin eruptions, itching and burning, red skin and eyes, facial swelling, and fever. Some people required hospitalization.28 The two lists are nearly identical—only “exacerbations of asthma” was on the spray list and not the other.
Asthma and breathing difficulties were reported by Filipinos who inhaled Bt-corn pollen.35 They also described swollen faces, flu-like symptoms, fever, and sneezing. Some individuals in both India and the Philippines also reported long-term effects after exposure. The list of symptoms in the Philippines, however, did contain items not reported by the other two groups. These included coughs, headache, stomachache, dizziness, diarrhea, vomiting, weakness, and numbness.30"