Juru River Research Articles

URBAN WATER SECURITY PROTECTION: IDENTIFYING POLLUTION SOURCES IN JURU RIVER BASIN USING CHEMOMETRICS

The consumption of surface water is becoming increasingly significant as a main solution for Malaysia's issues with water supply, especially in urban areas. The study addresses the protection of urban water security by multivariate analysis, evaluating trends in the distribution of water quality parameters and identifies the primary sources and processes involved in water quality contamination in the Malaysian Juru River Basin. Conventional graphical and multivariate statistical methods HACA and PCA from chemometric techniques were used. The data collected in the Juru River was subjected to this investigation, which recorded 19 physical-chemical and microbiological characteristics at two sampling locations throughout the Juru River Basin. Consequently, the HACA was effectively split into the downstream and upstream areas. Six VFs are displayed by PCA in the high pollution source area (HPS), which represents 81.11% of the variance. The main cause of a decrease in water quality in the downstream areas of the Juru River Basin is anthropogenic pollution, or pollution caused by human activities. The study concludes by demonstrating how chemometric techniques can be used to identify significant details about their capacity to interpret complex data that determines the Juru River Basin's spatial and temporal variation in water quality distribution trends into MPS and HPS areas to ensure the urban water security protection.

Anthropogenic disturbance of aquatic biodiversity and water quality of an urban river in Penang, Malaysia

Malaysia's rapid economic and demographic development have placed negative pressure on its water supplies and the quality of the Juru River, which is close to the nation's capital and its major source of water. Healthy aquatic ecosystems are supported by physicochemical properties and biological diversity. This study evaluated the anthropogenic impacts on aquatic biodiversity, especially plankton, fish, and macrobenthos, as well as the water quality of the Juru River in the Penang area. Aquatic biodiversity and river water parameters were collected from ten sampling stations along the Juru River. Seven variables were used to assess the physicochemical environment: pH, temperature, total suspended solids (TSS), salinity, dissolved oxygen (DO), biochemical oxygen demand (BOD), and chemical oxygen demand. At each sampling station, the total number of plankton, fish, and macrobenthic taxa were counted and analyzed. The relationships between the physicochemical parameters and aquatic biodiversity were investigated with biotypological analysis, principal component analysis, hierarchical cluster analysis, and linear regression analysis. These analyses showed that the richness and diversity indices were generally influenced by salinity, temperature, TSS, BOD, and pH. The data obtained in this study supported the bioindicator concept. The findings, as they related to scientifically informed conservation, could serve as a model for Juru River management, as well as for river management throughout Malaysia and other tropical Asian countries.

Decolorization of Reactive Red 120 by a novel bacterial consortium: Kinetics and heavy metal inhibition study

<abstract><p>Juru River is one of the most polluted rivers in Malaysia. A dye-degrading bacterial consortium has been isolated from the river's sediment. This consortium JR3 consists of <italic>Pseudomonas aeruginosa</italic> MM01, <italic>Enterobacter</italic> sp. MM05 and <italic>Serratia marcescens</italic> MM06, which were able to decolorize up to 700 ppm of the Reactive Red 120 (RR120) dye under optimal conditions with limited substrate available. Substrate inhibition kinetics were investigated, and, based on the best model, Aiba, the maximum growth rate was 0.795 h<sup>–1</sup>, while the saturation constant and inhibitory constant were 0.185% and 0.14%, respectively. In addition, the influence of various metal ions on the growth and decolorization rate of this bacterial consortium on RR120 was investigated. Chromium showed the weakest effect on the decolorization of 200 ppm RR120, with 73.5% removal and bacterial growth of 11.461 log CFU mL<sup>–1</sup>. Zinc yielded the second weakest effect, followed by silver and lead, with percentages of RR120 decolorization of 63.8%, 54.6% and 50.5%, respectively. Meanwhile, cadmium, arsenic and copper reduced the decolorization of RR120 in consortium JR3 by half. Mercury strongly inhibited decolorization by 32.5%. Based on the least inhibited heavy metal in RR120 decolorization activity of consortium JR3, the best inhibitory kinetic model was Levenspiel, with a maximum growth rate of 0.632 h<sup>–1</sup>, while the saturation constant and inhibitory constants were 15.08% and 0.5783%, respectively. The metal-tolerant azo dye-degrading bacterial consortium will be very useful in dye remediation in metal-laden polluted environments.</p></abstract>

Isolation and Growth Characterization of an Acrylamide-degrading Bacillus sp. strain UPM2021n Isolated from the Juru River

Polyacrylamide, in which acrylamide is the primary component, degrades back into acrylamide over time. Major amounts of acrylamide can be found in soil. The bioremediation strategy of using microbes to break down acrylamide is gaining popularity in many parts of the world. Several acrylamide-degrading bacteria have been isolated from sediment from the Juru River’s bank. The best isolate was a bacterium identified tentatively as Bacillus sp. strain UPM2021n based on cultural, colony morphology and biochemical tests. According to early studies, ideal growth parameters included a pH range of 6.5 and 7.0 and a temperature range of 25 to 35 degrees Celsius. Both glucose and sucrose performed at a similar level in supporting the growth of this bacterium on acrylamide as the sole nitrogen source. The highest growth occurs in between 300 and 500 mg/L of acrylamide, resulting in a growth of nearly 7.7 log CFU/mL with a nett growth of about 4 Log CFU/mL as compared to the control. Growth was nearly tolerated at the highest concentrations tested, which was 1500 mg/L and growth completely ceased at higher concentrations Toxic heavy metals tested such as mercury, copper, chromium, and cadmium showed that mercury strongly hampered growth on acrylamide whilst other metal ions such as copper, lead, cadmium, and chromium showed from 30 to 60% inhibition. The relatively high tolerance of acrylamide makes this bacterium suitable for remediation of soil contaminated with acrylamide whilst its sensitivity to heavy metals chiefly mercury means metal-chelating or sequestering compounds must be added to soil contaminated with both acrylamide and heavy metals.

Determination of Trace Elements in Sediments Samples by Using Neutron Activation Analysis

The Juru River is a highly industrialized, urbanized, and agricultural catchment. This study aimed to investigate trace elements in Juru mangrove sediments, including geochemical baselines and enrichment. Sediment was collected from the mangrove in Juru, Penang, Malaysia. A total of eight target elements was examined. Instrumentation activation analysis (INAA) was used to determine the concentration of Fe, V, Cr, Zn and Co. Atomic absorption spectrometry (AAS) was used to determine the concentration of elements that not detectable by INAA (Cd, Pb, and As). In both methods, validated reference material studies were used for validation of the methodology. Metal pollution was estimated using the Enrichment Factor (EF), Geoaccumulation Index (Igeo), Contamination Factor (CF), and Pollutant Load Index (PLI). The EF, Igeo, and CF ranges from 0.45–7.96, -2.18 – 1.95, and 0.33–5.83 respectively. The order of accumulation of the elemental concentration found was Fe > Zn> Cr > V > Pb > As > Co >Cd. The computed mean value of PLI exceeds the unit (PLI > 1).

Decolourisation of Reactive Red 120 by a Heavy Metal-tolerant Bacterium Isolated from Juru River, Malaysia

Application of dyes is prevalent in industries involved in textile and food manufacturing. Effluent discharge from these industries to neighbouring water bodies cause significant health concerns due to dye toxicity. To date, only very few bacteria are isolated with the ability to completely assimilate dyes. The main objective of this study is to isolate bacteria(s) with the ability to utilise reactive red dye 120. Local strains were isolated from contaminated sites in Northern Malaysia. Based on 16S rDNA gene sequence analysis, the best strain was identified as Pseudomonas sp. strain DRY011. Optimum RR120 decolourisation was observed at 200 ppm with 71.07% removal rate within 5 days and able to tolerate up to 500 ppm. The effect of heavy metals (silver, arsenic, cadmium, chromium, copper, mercury, lead and zinc) were investigated. Mercury, 1 ppm had the highest inhibition effect, followed by zinc and silver, with decolourisation of 12 % and 14.3 % respectively. Chromium had the least effect with 55.6% decolourisation and bacterial growth of 11.5 CFU/mL. The rest of the heavy metal had the least effect on the decolourisation rate. As a conclusion, the finding of microbial degrader able to utilise dye will become crucial bioremediation key in controlling the level of dye wastes in water bodies.

Assessment of water quality status using univariate analysis at Klang and Juru River, Malaysia

Klang River and Juru River which today suffers from water quality problems resulting from anthropogenic and geomorphology factors . The purpose of this study was to assess the water quality status from 2009 until 2013. 10 monitoring stations covering along Klang River and Juru River were selected. Six water quality parameters analyzed based on in-situ and ex-situ analysis were carried out according to the univariate analysis to obtain WQI level. The result indicated the impact of various anthropogenic and geomorphology activities contributed higher values of BOD, COD, SS and NH 3 -NL but the TSS concentration contamination at Juru River still on stable condition. Downstream and middle stream more polluted than upstream area triggered by pollutants from waste products of development activities, which inclusion of a high amount of pollutants of Klang River and Juru River.

Heavy metal concentrations in fishes from Juru River, estimation of the health risk.

This study examined the concentration of heavy metals in 13 fish species. The results indicated that shellfish species (clams) have the highest metal concentrations, followed by demersal and pelagic fishes. The mean concentration of metals in clams are Zn 88.74±11.98µg/g, Cu 4.96±1.06µg/g, Pb 1.22±0.19µg/g, Cd 0.34±0.04µg/gdry wt. basis, whereas the same measure in fish tissues was 58.04±18.51, 2.47±1.21, 0.58±0.27 and 0.17±0.08µg/gdry wt. basis. The concentrations of heavy metals in clams and fish tissues were still lower than the maximum allowable concentrations as suggested by the Malaysian Food Act (1983) and are considered safe for local human consumption.

Monitoring of heavy metals level in fish using Photobacterium sp. strain MIE


 Luminescence-based assays for toxicants such as Microtox®, ToxAlert™ and Biotox™ have been used extensively worldwide. However, the use of these assays in near real-time conditions is limited due to nonoptimal assay temperature for the tropical climate. An aerobic isolate that exhibits a high luminescence activity in a broad range of temperatures was successfully isolated from the mackerel, Rastrelliger kanagurta. This isolate was tentatively identified as Photobacterium sp. strain MIE, based on partial 16S rDNA molecular phylogeny. Optimum conditions that support high bioluminescence activity occurred between 24 and 30 oC, pH 5.5 and 7.5, 10 and 20 g/L of sodium chloride, 30 and 50 g/L of tryptone, and 4 g/L of glycerol as the carbon source. Assessment of near real-time capability of this bacterium for heavy metals in a contaminated river running through the Juru River Basin that fed a large agriculture area has shown near real-time capability with assaying time of less than 30 min per samples. Thus, this strain is suitable for near real-time monitoring of toxicants especially in the tropics

Heavy Metals Nickel and Chromiumin Sediments in the Juru River, Penang, Malaysia

Study was conducted to determine the concentrations of (Ni) and (Cr) in sediment and to investigate the effect pH and organic matters on concentrations of nickel and chromium in sediment at Juru River, Penang, Malaysia. The sequential extraction procedure was used based on defined fractions: exchangeable, acid reduction, oxidation and residual. The concentrations of Ni and Cr in residual fraction were higher than the other fractions. In non-residual fractions, the concentration of heavy metals in organic matter fraction was much higher than other fractions (6.63 ± 3.90 μg/g-1 dry weight ) for nickel and (6.44 ± 2.10 μg/g-1 dry weight) for chromium. The pH of the sediment in all sites was acidic. The mean of total concentrations of Ni and Cr was 38.21 and 24.92 μg/g-1 dry weight, respectively. Results of organic matter analysis showed that the percentage of organic matter present in sediment samples varied throughout the river and all sites of sediments were ranged from 7.10% to 16.20%. Comparison between sampling sites using one-way analysis of variance showed that there were significant differences for Ni (P P > 0.05) in changeable fraction. At acid reduction, oxidation and residual fractions, there were significant differences for the two metals (P P P > 0.05). Analysis of pH and percentage of organic matter present in sediment conclude that Ni and Cr were not strongly correlated at oxidation fraction.

Heavy Metal Concentrations (Cu, Cd and Pb) in Sediments in the Juru River, Penang, Malaysia

Heavy Metal Concentrations (Cu, Cd and Pb) in Sediments in the Juru River, Penang, Malaysia

Concentration of selected heavy metals in water of the Juru River, Penang, Malaysia

This study was conducted to determine heavy metal lead (Pb), cadmium (Cd), Zinc (Zn) and copper (Cu) concentrations in water body of the Juru River, Penang, Malaysia. A total of 20 sampling stations were chosen and water at 1 m below the surface was sampled using Van Dorn water sampler in December 2009 and April 2010. Collected water samples were kept in ice and acidified to pH 2 using nitrite acid (analytical grade HNO 3 ). Heavy metal concentrations were determined using inductively couple plasma (ICP model Perkin elmer/elan 9000) following standard method procedures. For comparison purposes, the river was divided into three different zones in the first and second samplings that is, upstream zone, middle reach zone and estuary zone and each zone consists of 7, 7, 6 sampling sites, respectively. Generally, results indicate that Pb and Cd and Cu in the first sampling were higher than the second sampling while the concentrations of Zn in the second sampling were higher than the first sampling. Also the results indicate that the Cd and Pb and Zn in the estuary zone were the lowest as compared to other zones. Meanwhile the highest concentration of Cu was in the middle zone. In conclusion, the lowest concentrations of some heavy metals were in estuary zone, it seems to be naturally due to dilution to heavy metals from sea water. Average metal concentrations from 20 water samples indicate that studied metal concentrations were still lower than Malaysian’s National Water Quality Standards (INWQS) guideline. Keywords: Heavy metals, pollution, river, inductively couple plasma

Artificial Neural Networks Combined with Sensitivity Analysis as a Prediction Model for Water Quality Index in Juru River, Malaysia

The manuscript describes the application of artificial neural networks (ANNs) for the series modeling of surface water quality prediction in Juru River, Malaysia. This is based on water quality data from twelve monitoring stations of Juru River (6 January 2003 until 5 November 2007) provided by Department of Environment (DOE), Malaysia. Thirty physicochemical parameters were involved in this analysis as input variables and water quality index as output variable. Three models were proposed to identify the most effective model in attempt to predict the WQI. Sensitivity analysis (SA) was carried out by using leave one out approach in order to indentify the most significant input-output relationship. The ANNs developed was successfully trained and tested using the available data sets and the performance of ANNs models was determined by coefficient of determination (R 2 ), coefficient of correlation (R) and root mean square error (RMSE). Results show that ANN-1 gives the higher value of R 2 (0.9942) and RMSE (2.8966), however this model was only trained and tested using all available parameters. The second model (ANN-2) gives R 2 value (0.9839) slightly higher compare to the third model, ANN-3 (0.9811). This is supported by the RMSE values which indicate that ANN-2 has a lower value compared to ANN-3 which is 2.1877 and 2.411. Hence, this study will trigger DOE to use ANNs in order to predict WQI other than using conventional method (WQI equation) that is currently being used by DOE. In addition, the ANNs managed to show remarkable prediction performance to predict the WQI in Juru River.

Influence of agricultural, industrial, and anthropogenic stresses on the distribution and diversity of macroinvertebrates in Juru River Basin, Penang, Malaysia

Abundance and diversity of benthic macroinvertebrates as well as physico-chemical parameters were investigated in five rivers of the Juru River Basin in northern Peninsula Malaysia: Ceruk Tok Kun River (CTKR), Pasir River (PR), Permatang Rawa River (PRR), Kilang Ubi River (KUR), and Juru River (JR). The physico-chemical parameters and calculated water quality index (WQI) were significantly different among the investigated rivers (ANOVA, P<0.05). The WQI classified CTKR, PR, and JR into class III (slightly polluted). However, PRR and KUR fell into class IV (polluted). High diversity and abundance of macroinvertebrates, especially the intolerant taxa, Ephemeroptera, Plecoptera, and Trichoptera, were observed in the least polluted river, CTKR. Decreasing abundance of macroinvertebrates followed the deterioration of river water quality with the least number of the most tolerant taxa collected from PR. On the basis of composition and sensitivity of macroinvertebrates to pollutants in each river, the highest Biological Monitoring Working Party (BMWP) index score of 93 was reported in CTKR (good water quality). BMWP scores in PRR and JR were 38.7 and 20.1, respectively, classifying both of them into “moderate water quality” category. Poor water quality was reported in PR and KUR. The outcome of the multivariate analysis (CCA) was highly satisfactory, explaining 43.32% of the variance for the assemblages of macroinvertebrates as influenced by 19 physical and chemical variables. According to the CCA model, we assert that there were three levels of stresses on macroinvertebrate communities in the investigated rivers: Level 1, characterized of undisturbed or slightly polluted as in the case of CTKR; Level 2, characterized by a lower habitat quality (the JR) compared to the CTKR; and Level 3 showed severe environmental stresses (PRR, PR, and KUR) primarily contributed by agricultural, industrial, and municipal discharges.

Study on the Impact of Tidal Effects on Water Quality Modelling of Juru River, Malaysia

This study on water quality modelling in Sungai Juru, Penang was undertaken as one of the most polluted rivers in Malaysia and is literally known as the 'dying river'. The research objectives are to assess the parameters that govern the amount of pollutants in the river and to identify appropriate measures to improve the river water quality. The main pollution sources are pig waste, discharge from agro-based industries, dumping of municipal and industrial waste. Due to its relatively flat bed gradient, Sungai Juru experienced tidal effect up to a distance of 13 km from the estuary. As a result, pollutants in the river are hardly discharged into the sea. This research on Dissolved Oxygen (DO) parameter has been carried out to develop a rehabilitation solution for Sungai Juru by using the numerical hydrodynamic modeling technique simulated by I-D Infoworks R.S software. The modeling involved two phases namely, development of a flow model followed by a water quality model. After the model has been successfully calibrated, the pollutant behaviour under various scenarios can be investigated. The hydraulic study of Sungai Juru revealed that the velocity at STJ02 ranging from -0.1 to +0.12 m sec-1 during high and low tide, respectively. Based on this velocity, traveling time from S TJ02 (Sungai Juru) to STJ01 (Sungai Rambai) (3.5 km) is approximately between 9-10 h. The duration provides ample time for photosynthesis to occur resulting high DO ranging from 4-10 mg at STJ01. The information is useful to determine pollution characteristics in Sungai Juru particularly related to tidal impacts. It is hoped that the modeling technique developed can be applied in other rivers in Malaysia which are subjected to tidal influences.

Assessment of Cu, Pb, and Zn contamination in sediment of north western Peninsular Malaysia by using sediment quality values and different geochemical indices

Surface sediments were collected from the north western aquatic area (13 intertidal sites and 5 river drainages) of Peninsular Malaysia, which were suspected to have received different anthropogenic sources. These sites included town areas, ports, fishing village, industrial areas, highway sides, jetties and some relatively unpolluted sites. The present study revealed that 4.79-32.91 μg/g dry weight for Cu, 15.85-61.56 μg/g dry weight for Pb, and 33.6-317.4 μg/g dry weight for Zn based on 13 intertidal surface sediments while those based on 5 river drainage surface sediments were 10.24-119.6 μg/g dry weight for Cu, 26.7-125.7 μg/g dry weight for Pb and 88.7-484.1 μg/g dry weight for Zn. In general, the metal levels in the drainage sediments are higher than in the intertidal sediments, suggesting dilution factor in the intertidal sediment and direct effluent from point sources in the drainage sediment. In particular, the total concentrations of Cu, Pb, and Zn for the sampling site at Kuala Kurau Town exceeded the Effect Range Median values for Cu, Pb, and Zn for assessments of sediment quality values for freshwater sediment as proposed by MacDonald et al. (Arch Environ Contam Toxicol 39:20-31, 2000), thus adverse biological effects would be observed above this level. Assessment using enrichment factor (using Fe as a normalizer) and geoaccumulation index showed that the three metals at Kuala Kurau Town and Juru Industry drainage were evidenced as having more enrichment and mostly due to non-natural sources. However, caution should be exercised that the interpretation can only become valid when the ratios, indices, and sediment quality values are combined. This is due to the fact that not all the established indices are applicable and, to a certain extent, some of them should be further revised and improved to suit a different metal for Malaysian sediment. Undoubtedly, sites near drainages at Kuala Kurau Town and Juru River Basin need greater attention to mitigate the heavy metal pollution in the future.

Distribution of Chironomidae (Insecta: Diptera) in polluted rivers of the Juru River Basin, Penang, Malaysia

The influence of physical and chemical parameters on the abundance and diversity of chironomids was studied in six rivers with moderate to highly polluted water in the Juru River Basin. The rivers: Ceruk Tok Kun (CTKR) as reference site, and polluted rivers of Pasir (PR), Juru (JR), Permatang Rawa (PRR), Ara (AR) and Kilang Ubi (KUR) were sampled over a period of five months (November 2007-March 2008). Nine chirnomid species: Chironimus kiiensis, C. javanus, Polypedilum trigonus, Microchironomus sp., Dicrotendipes sp., Tanytarsus formosanus, Clinotanypus sp., Tanypus punctipennis and Fittkauimyia sp. were identified. Assessment of their relationships with several environmental parameters was performed using the canonical correspondence analysis (CCA). Tanytarsus formosanus was the most dominant in the relatively clean CTKR and moderately polluted JR with mean densities of 19.66 and 25.32 m −2, respectively while C. kiiensis was abundant in more polluted rivers. Tanytarsus formosanus, Dicrotendipes sp. and Microchironomus sp. were grouped under moderate to high water temperature, total organic matter (TOM), total suspended solids (TSS), velocity, pH, phosphates and sulphates. However, Tanypus punctipennis, Fittkauimyia sp., and Clinotanypus sp. were associated with high contents of river sediment such as TOM, Zn and Mn and water ammonium-N and nitrate-N and they were associated with higher dissolved oxygen (DO) content in the water. Chironomus kiiensis, C. javanus and P. trigonus showed positive relationships with TOM, ammonium-N and nitrate-N as well as trace metals of Zn, Cu and Mn. These three species could be considered as tolerant species since they have the ability to survive in extreme environmental conditions with low DO and high concentrations of pollutants. Based on the water parameter scores in all rivers, the highest diversity of chironomid larvae was reported in CTKR. With higher concentrations of organic and/or inorganic pollutants as reported in PPR, KUR and AR, the chironomid larval diversity decreased, and the abundance of tolerant species, mainly Chironomus spp., increased.

Heavy metal concentrations in the different tissues of horseshoe crabs collected from intertidal sites of the polluted Juru River and the relatively unpolluted Sepang Besar River, Peninsular Malaysia

Horseshoe crabs (Tachypleus gigas) were collected from intertidal sites of the polluted Juru River (Penang) and the relatively unpolluted Sepang Besar River (Selangor) in September and December 2007. They were dissected into six parts namely carapace, muscle, telson, leg, operculum and gills. For each site, different tissues from the horseshoe crabs were determined for the concentrations of Cd, Cu, Ni, Fe, Pb and Zn in them. Gills accumulated the highest concentrations of Cu, Cd, Fe, Ni and Pb. Muscles were found to have the highest concentrations of Zn. Most distinctively, the concentrations of Cu, Ni and Zn in the muscles of the Juru River population were significantly (P&lt; 0.05) higher than those from the Sepang Besar River, indicating that the Juru River had higher contaminations and bioavailabilities of these metals than the Sepang Besar River. This conclusion was also well supported by the sediment data. These results suggest that T. gigas (especially the muscle) is a potential biomonitor of Cu, Ni and Zn contaminations and bioavailabilities in tropical intertidal areas.

Evaluation of mentum deformities of Chironomus spp. (Chironomidae: Diptera) larvae using modified toxic score index (MTSI) to assess the environmental stress in Juru River Basin, Penang, Malaysia

Morphological mentum deformities which represent sublethal effect of exposure to different types of pollutants were evaluated in Chironomus spp. larvae inhabiting three polluted rivers of Juru River Basin in northwestern peninsular Malaysia. Using mentum deformity incidences, the modified toxic score index (MTSI) was developed based on Lenat's toxic score index (TSI). The suggested MTSI was compared with TSI in terms of its effectiveness to identify different pollutants including heavy metals. The MTSI showed stronger relationship to total deformity incidence expressed as percentage. Additionally, the multivariate RDA model showed higher capability of MTSI to explain the variations in heavy metal contents of the river sediments. The MTSI was recommended in bioassessment of water and sediment quality using the mentum deformities of Chironomus spp. larvae from aquatic ecosystems receiving anthropogenic, agricultural, or industrial discharges.

Fluctuating Asymmetry of Chironomus spp. (Diptera: Chironomidae) Larvae in Association with Water Quality and Metal Pollution in Permatang Rawa River in the Juru River Basin, Penang, Malaysia

The levels of fluctuating asymmetry [random differences between symmetric organismal traits, fluctuating asymmetry (FA)] in the fourth instar of Chironomus spp. larvae inhabiting an agrochemical polluted river [Permatang Rawa River (PRR)] in the Juru River Basin, northeastern peninsular Malaysia, were measured. The PRR receives waters primarily from adjacent rice fields which are exposed to fertilizer and pesticide residues. Samples of larvae, water, and sediments were collected monthly from November 2007 to June 2008. In situ measurements of water pH and dissolved oxygen were made at three sampling locations along the river. Monthly water and benthic sediment collections were also conducted for the following laboratory water analyses: biological oxygen demand (BOD), chemical oxygen demand (COD), total suspended solids (TSS), and ammonium-N content. Non-residual metals in the sediment samples were also analyzed. The water quality index (WQI) of the PRR was also calculated. This study attempted to relate FA levels based on selected traits of Chironomus spp. larval head capsule (mentum width and first and second antennal segment length) to water quality and sediment heavy metal contamination in the PRR. All monthly measurements of FA levels including transcriptors (FA10a, FA4a, ME3, and ME1) and indices [FA, absolute asymmetry (AbsFA), and composite fluctuating asymmetry (CFA)] were calculated. The ordination model of redundancy analysis showed that the dissolved oxygen and water quality in the river expressed as WQI were negatively correlated with all FA indices (FA, AbsFA, and CFA) of the larval mentum width and length of antennal segments I and II. The water pH, BOD, and COD and sediment Cu positively influenced the FA incidence in the larval mentum. The FA indices of the antennal segment I were positively correlated with the increase in the levels of water pH, ammonium-N, BOD, and COD. The FA indices, especially CFA, were sensitive to the water pH and ammonium-N and sediment contaminated by Mn, Cu, and Zn. The FA levels calculated as FA indices of the larval antennal segment II length were positively correlated with water TSS and sediment Mn, Cu, Zn, and Ni. This study revealed that the river water quality and heavy metal contamination affect developmental stability in Chironomus spp. larvae. The FA indices of different structures in the Chironomus spp. larval head capsule could be used as bioindicators for water and sediment pollution.