  The spectral singularity have been extensively studied over the last one and
half decade for different non-Hermitian potentials in non-Hermitian quantum
mechanics. The nature of spectral singularities have not been studied for the
case of quaternionic potential. In the present work we perform an analytical
study for the scattering from a quaternionic point interaction represented by
delta function. New features of spectral singularities are observed which are
different than the case of complex (non-quaternionic) point interaction. Most
notable difference is the occurrence of spectral singularity from lossy point
interaction which is forbidden in the case of standard non-Hermitian quantum
mechanics.
