2019_EJRNL_PP_SIMONE_BAGNIS_1.pdf
Terbatas Lili Sawaludin Mulyadi
» ITB
Terbatas Lili Sawaludin Mulyadi
» ITB
The direct discharge of untreatedwastewater has been identified as an important source of environmental contamination
by active pharmaceutical ingredients and other ‘down-the-drain’ chemicals in developing countries. It necessitates
the development of an environmental risk assessment approach for the resulting impact zone. This studywas
designed to investigate the impact of lowlevel of dilution (b10) on the natural attenuation processes of distribution
and degradation within the impact zone. Dilution of the untreatedwastewater resulted in increased desorption and
corresponding environmental concentrations. The presence/absence of the microbial population in the batches
affected the degree of sorption depending on the compound charge (i.e. positive or negative), highlighting an experimental
technical bias. The degradation half-lives of acebutolol and diclofenac increased with increasing dilution and
resulted in higher environmental persistence. The modelling of the biochemical oxygen demand (BOD) allowed an
estimate of the temporal end boundary of the impact zone to be predicted as 24 h. Therefore, itwas concluded that
most of the investigated compounds would persist beyond the end of the impact zone as defined by the return to
environmental BOD concentrations. It is proposed that, within environmental risk assessment protocols, the impact
zone should be considered as a semi-natural wastewater treatment area in such a way to allow the estimate of
environmental concentrations of pharmaceuticals beyond its end