1 The botulism neurotoxin is one of the most potent, lethal substances known.  Botulism is a disease caused by this neurotoxin (specifically A, B, E, or F type neurotoxin); symptoms include a flaccid paralysis (weakness or slackness) in various muscles.
On that trip I used both Gatwick and Heathrow airports, as I stayed in London a few days then went on to Madeira, Portugal via Gatwick. When I first arrived from the US, I came into London Gatwick around 8am. The line for customs was miles long and it took about 30 minutes to get through.But when I came into Gatwick around 5pm from Madeira it was a ghost town. I kid you not, there wasn't a soul in the line, and the baggage re-claim area was dead quiet.ast Tuesday, it took 45 minutes to get to an immigration officer through a queue line that would do Disneyland proud...the immigration inspection took oh about 15 seconds, she looked at my landing card, my passport, asked how long I would be in the UK, stamped my passport and said, off you go..
The exception would be if you have an international flight, and are making the connection in a different country than you started in, then you may have to clear customs at the connecting airport rather than the final destination.n that case you have to get your bags, clear customs, re-check your bags (or at least drop them off at specific location, depending on the airport), and clear security again. When the airline tells you to check in 2 hours before departure, they mean it regardless of whether you're checking bags or not.