Want to take part in the newest viral challenge? All you have to do is eat an egg with its shell still on. The "shell on" challenge can also entail biting into an unpeeled banana or chomping into foods still wrapped inside plastic or cardboard packaging. While amusing, doctors warn that the internet dare can pose serious health risks, such as salmonella and pesticide contamination,TODA Yreports. Eating packaging is dangerous and may contain phthalates and carcinogenic substances. The "shell on" challenge also poses serious choking hazards.