Evidence map›Paper›PMID 41733708›Full record

ArticleEnvironmental monitoring and assessment2026

Heavy metal contamination in sediments of the Sematan-Serayan River, Sarawak: Assessment of pollution indices and environmental risk implications.

Farah Akmal Idrus, Valerie Urai Ding

Abstract read
In one paragraph

Article in Environmental monitoring and assessment, 2026. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 1 paper.

0numbers the graph read from it
0cells of the map it votes in
1citing papers in PubMed
–field-weighted citation impact
1 · What the graph read from it

What it found

Each row is one number read from the abstract, on the scale the paper reported it, with its interval. Left of the dashed line favours the treatment, right favours the comparator. Under each row is the sentence it came from. New to these charts? A ten-minute tutorial.

The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.

2 · The registry

The trial behind it

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Neither the registry nor the abstract names a trial number. If this is a trial report, that itself is worth knowing.

3 · Its place in the literature

Who cites it

1 citing paper in PubMed.

  1. Review
4 · The record

Corrections and comments

PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.

5 · Who and what money

Authors and funding

2 authors.

Farah Akmal IdrusFaculty of Resource Science and Technology, Universiti Malaysia Sarawak (UNIMAS), 94000 Kota Samarahan, Sarawak, Malaysia. aifarah@unimas.my.ORCID http://orcid.org/0000-0003-3095-1707
Valerie Urai DingFaculty of Resource Science and Technology, Universiti Malaysia Sarawak (UNIMAS), 94000 Kota Samarahan, Sarawak, Malaysia.

Funding

Shell Chair Grant Scheme UNI/F07/SHC/85541/2023
6 · The paper itself

Abstract

Sediments in river systems act as both sinks and sources of pollutants, which can have significant environmental and health implications. This study aimed to assess the concentrations of heavy metals in relation to total organic carbon (TOC) in the sediments of the Sematan-Serayan River, Sarawak, Malaysia. Sediment samples were collected in November 2024. Heavy metal and TOC concentrations were analysed via flame atomic absorption spectroscopy and a TOC analyser, respectively. The average heavy metal concentrations decreased in the order of Fe > Al > As > Zn > Ni > Cr > Pb > Mn > Cu > Co > Cd. Higher heavy metal concentrations associated with TOC were observed, particularly at stations close to anthropogenic activities, indicating pollution hotspots. The surface sediments were dominated by sand (> 90%). Pollution indices, including the contamination factor (CF), geoaccumulation index (Igeo), pollution load index (PLI), and potential ecological risk index (RI), were used to assess the severity of environmental pollution. All the stations were highly contaminated (CF > 6) and moderately to strongly polluted by Pb and As (Igeo > 2). Moreover, Stations 1 and 3-7 were considered deteriorated zones during the monsoon season (PLI > 1). The RI was very high (RI > 600) for Pb, As, Cu, Zn, and Cr at all stations. A comparison of the pollution indices with hierarchical cluster analysis suggested that anthropogenic activities were the main sources of heavy metal contamination in this river, potentially disturbing the biological functions of the benthos.

Indexed as

Environmental MonitoringGeologic SedimentsMetals, HeavyRiversWater Pollutants, ChemicalMalaysiaRisk AssessmentMetals, HeavyWater Pollutants, ChemicalAnthropogenic sourcesHeavy metalsSediment pollution indicesSematan-Serayan River SarawakTotal organic carbon

Identifiers

PMID41733708
PMCPMC12932345

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Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.