Shots of different aircraft were used for takeoff, in-flight and landing.
Photos of the 737 airliner taking off show a plane with long and thin turbojet engines used on early models. Inflight photos show a later model with short, stout turbofan engines.
The airliner has no carrier or airline branding or logo of any kind on the outside. It's completely unmarked.
An aircraft departing London would not be cruising at 41,000 feet over the English Channel. It would not reach that altitude until almost into Germany.
Malcolm says that one gram of dimethylmercury is enough to kill 1 million people. Although dimethylmercury is one of the strongest known neurotoxins, a lethal dose is about 50 micrograms per kg of body weight meaning about 3-5 milligram would be a lethal dose for an adult of average weight. 1 gram would be enough to kill 200-300 people, not a million.
The tail number of the aircraft on the ground in Turkey was "N88892". Aircraft from the UK have numbers which begin with "G". (The FAA Number Registry lists N88892 as "reserved", with a purge date of 99/99/9999.)