Is the hot air emitted by celebrities when they spout ecological platitudes a greenhouse gas? If so, then the melting of the polar ice caps just moved a step closer, following calls by Trudie Styler, a leading celebrity ecological hypocrite - call them hippy-crites for short - for the general public to eat more locally grown vegetables.
Campaigning against food miles might seem an unlikely cause for Styler, given that a tribunal last year heard how she ordered her personal chef to travel over 100 miles to make a bowl of pasta for her youngest child and has sold olive oil and honey from her Tuscan estate, Il Palagio, 1,000 or so miles away, in Harrods in London.
So it was hardly surprising that an alert journalist present at the lecture, which was being staged as part of the Earls Court Real Food Festival, had the wit to question the environmental record of Styler and her husband Sting.
The couple's carbon footprint, the impertinent ink-stained wretch pointed out, has been estimated at 30 times greater than the average Briton's. How did Styler and Sting - who have seven homes - square that with their environmental crusading?