Step-by-step explanation:
1) The letter — with copies to the health and the science and technology ministry — cites medical studies to buttress the charge that our lucre is, indeed, filthy and can give rise to septicaemia, skin infections, toxic shock syndrome and various gastrointestinal complaints.
2) Thornton Wilder observed that money is like manure in that neither is any use unless it gets spread around.
3) It might be less than fair to liken money to an indigenous form of fertiliser that in idiomatic usage is abbreviated to BS
4) However, it seems that our currency is far from coming up smelling of roses. The Confederation of All India Traders (CAIT) has petitioned finance minister Arun Jaitley for action to prevent people handling cash from contracting diseases from germ carrying banknotes.