Active biomonitoring in streams by using multimarker approaches of mussels

BACKGROUND AND OBJECTIVES: Streams that pass through densely populated areas and business and industrial centers are continuously threatened by various pollutants, including metals and microplastics, originating from dispersed sources. Biomonitoring is necessary to evaluate the
health of stream ecosystems, considering that streams are essential ecologically and for human life. A biomonitoring approach through multimarkers can provide a comprehensive picture of the
condition of stream ecosystems. It can identify biomarkers that are sensitive and specific to the
presence of certain types of pollutants. This study evaluates the ecosystem health of Code Stream,
Yogyakarta, Indonesia, through active biomonitoring by transplanting mussels Anodonta woodiana
into cages at three stations, representing mild (station 1), moderate (station 3), and severe (station
2) polluted ecosystem conditions based on human activities around the stream.
METHODS: The mussels were transplanted into the Code Stream. Then, on days 0, 3, 7, 14, 21,
and 28, the organisms were taken, and their gills and mantle were dissected in the laboratory. The
organs were analyzed for microplastic accumulation and characteristics, copper concentration,
superoxide dismutase, catalase, acetylcholinesterase activities, metallothionein concentration, and
deoxyribonucleic acid damage. Biomarkers sensitive to pollutants were evaluated by integrated
biomarker response. The combined effects of the complexity of environmental factors on the
biomarkers were analyzed by multiple-factor analysis.
FINDINGS: The Code Stream waters at all stations were polluted with microplastics and copper.
The increase in the two pollutants in the mussel organs was a function of time, with no differences
among stations. The abundance of microplastics and copper concentrations in the water was closely
related to their accumulation in both organs. Exposure to various contaminants in the stream
strongly increased the superoxide dismutase and catalase activities in both organs at the beginning
of exposure in all stations, with the highest being at station 3. The acetylcholinesterase activity was
strongly inhibited in the gills at station 2. The metallothionein concentration slightly increased, and
the highest increase occurred in the gills at station 2. The deoxyribonucleic acid damage was more
intense at stations 2 and 3. Integrated biomarker response analysis showed that deoxyribonucleic
acid damage, catalase activity, and metallothionein concentration were biomarkers responsive
to stream pollution. Multiple-factor analysis revealed that superoxide dismutase, catalase, and
acetylcholinesterase activities were biomarkers that indicated the environmental pollution of Code
Stream waters. Multimarker analysis confirmed that the pollution level at stations 2 and 3 was
higher than at station 1.
CONCLUSION: Active biomonitoring can offer a more accurate and comprehensive view of the
time-dependent link between exposure and biomarker response. This active biomonitoring strategy
identified sensitive and specific biomarkers for the presence of metal and pesticide contaminants
in stream ecosystems. The pollution of Code Stream waters harms oxidatively stressed mussels and
may endanger human health via the food chain. This work contributes substantially to understanding
pollution exposure and its effect on mussels. It develops pollution-sensitive biomarkers for routine
stream health monitoring. Mitigation activities involving diverse stakeholders and public education
on sustainable management efforts must continue to achieve sustainable development.