LUSI (Lumpur“mud”-Sidoarjo) is the mud volcanic which was initiated by the failed gas drilling exploration activities
carried out near an urban area. The evaluation of the LUSI mud volcanic emission and its dried mud effects on air pollution
and human health was carried out from 2011 to 2012. The concentrations of particulate matter (PM2
.
5
), hazardous
gases (H2
S, SO2
, NO2
), volatile organic compounds (VOC): Including total hydrocarbons (THC)), toluene (C6
H5
CH3
) and
benzene (C6
H6
) as well as heavy metals (Pb, Cr and Cd) were measured following standard methods. The results showed
that the average concentration of PM2.5 ranged from 24.0-399.9 μg/m3
, H2
S: 1.53-2.92 ppm; SO2
: 0.021-1.321 ppm and
NO2
: 0.007-0.076 ppm. The VOC included total hydrocarbons from 0.57-0.96 ppm, toluene 0.33-0.92 ppm and benzene
0.33-0.40 ppm. Furthermore, heavy metal concentrations were as follows: Pb 2.6-37.34 μg/m3
; Cr 0.14-12.8 μg/m3
and
Cd 0.78-4.16 μg/m3
. LUSI contributed to increased air pollution primarily through H2
S, SO2 and PM2.5. The Air Quality
Index (AQI) of PM2.5 (164-217) and SO2
(235-291) showed that the air quality at the disaster area was ‘very unhealthy’.
Backward trajectories indicated that the wind direction may have had an impact on the air pollution load.
The Sidoarjo mud is the first visible phenomenon of a mud volcano that occurs in a human settlement and which is
subsequently channelled into a river. Clay, aluminium and iron were reported to be the dominant contaminants that could
possibly come into contact with and accumulate on the surface of local fish and initiate alteration in scale microstructure.
The aim of this study was to evaluate the extent of water body contamination in the Sidoarjo mud by evaluating the
chromatophore density and microstructure deformation of fish scales that act as biomarkers. Scale samples were
obtained from caged Mozambique tilapia (Oreochromis mossambicus) fish that were placed downstream and upstream
of the Sidoarjo mud spillway pipes. With respect to melanophore density, it was found that the scales of fish exposed in
the downstream section were significantly lower in chromatophores (<50 chr/mm²) than the control scales in fish from
the upstream station (>100 chr/mm²). This study suggested that the density of chromatophores was closely related to
the concentration of total suspended solids (r = 0.69), which was possibly enhanced by iron (r = 0.56). Using scanning
electron microscopy analysis, some deformation, i.e. irregularity of spherule shape and increasing pits in the space
between ridges, were observed.