  We show how, in the presence of quantum noises generated by non-commuting
Lindblad operators, a maximally entangled Bell state may suffer entanglement
sudden death (ESD). Similarly, ESD may occur when a Bell state is under the
action of a quantum operation generated by a Hamiltonian in the presence of a
quantum noise, provided that the Hamiltonian does not commute with the
corresponding Lindblad operator. Practically this means noisy quantum
operations could cause ESD during the encoding process in quantum communication
protocols like special dense coding ($\cal S$). Next, we show how in the
presence of quantum noises which cause ESD, a Bell state may lose its capacity
for $\cal S$ before ESD occurs. Finally, we show that a Bell state may indeed
fail to yield information transfer better than classically possible when the
encoding operations of $\cal S$ are noisy, even though entanglement is not
totally destroyed in the process.
