Spatial assessment and source identification of heavy metals pollution in surface water using several chemometric techniques Azimah Ismail a , Mohd Ekhwan Toriman a, ⁎, Hafizan Juahir a , Sharifuddin Md Zain c , Nur Liyana Abdul Habir a , Ananthy Retnam b , Mohd Khairul Amri Kamaruddin a , Roslan Umar a , Azman Azid a a East Coast Environmental Research Institute (ESERI), Universiti Sultan Zainal Abidin, Gong Badak Campus, 21300 Kuala Terengganu, Malaysia b Environmental Health Division, Department of Chemistry Malaysia, Ministry of Science, Technology and Inovation, Jalan Sultan, Petaling Jaya, Selangor, Malaysia c Chemistry Department, University of Malaya, 50603 Kuala Lumpur, Malaysia abstract article info Article history: Received 27 June 2015 Received in revised form 7 October 2015 Accepted 11 October 2015 Available online xxxx Keywords: Heavy metals Straits of Malacca Principal component analysis Chemometric Source apportionment This study presents the determination of the spatial variation and source identification of heavy metal pollution in surface water along the Straits of Malacca using several chemometric techniques. Clustering and discrimina- tion of heavy metal compounds in surface water into two groups (northern and southern regions) are observed according to level of concentrations via the application of chemometric techniques. Principal component analysis (PCA) demonstrates that Cu and Cr dominate the source apportionment in northern region with a total variance of 57.62% and is identified with mining and shipping activities. These are the major contamination contributors in the Straits. Land-based pollution originating from vehicular emission with a total variance of 59.43% is attributed to the high level of Pb concentration in the southern region. The results revealed that one state representing each cluster (northern and southern regions) is significant as the main location for investigating heavy metal concen- tration in the Straits of Malacca which would save monitoring cost and time. Capsule: The monitoring of spatial variation and source of heavy metals pollution at the northern and southern regions of the Straits of Malacca, Malaysia, using chemometric analysis. © 2016 Elsevier Ltd. All rights reserved. 1. Introduction The increase in urbanization has led to an increase of pollutant dis- charge points into the Straits of Malacca, from both land-based and sea-based sources in a bulk-scale (Abdullah et al., 1999). Anthropogenic inputs contribute to the presence of pollutants that exhibit high toxicity into the marine ecological environment. The potential accumulation of waterborne heavy metals particularly Cadmium, Cuprum, Lead and Arsenic may have potential threat to the natural environmental marine communities and aggravate human health (Zakaria and Takada, 2007). In Malaysia, most pollutants are generated from industrial activities, in- tentional discharge from operation of vessels at ports, gas and crude oil platforms, petroleum refining and fertilizer manufacturing. According to Department of Environment (DOE) (2008), extensive changes in land use and industrialization have cause proliferation of heavy metal wastes like cadmium (Cd), copper (Cu), lead (Pb) and mer- cury (Hg), specifically in the littoral states; Pulau Pinang, Perak, Selang- or and Malacca into the Malacca Straits. Manufacturing sectors contribute a wide variety heavy metal pollutants in the coastlines of Western Peninsular Malaysia (Thia-Eng et al., 2000). Persistent organic pollutants (POPs) from the petroleum spills or tanker wreckage such as nickel and copper have environmentally contaminated and polluted the seawater surface and sediment, leading to the accumulation of heavy metals in aquatic systems (Santos-Echeandia et al., 2009). In addition, marine estuarine environment will be significantly impacted from accumulation of toxic substances and oil spill (Sun et al., 2012). Metal concentrations in sediment cores for example, were detected to be con- siderably higher in 1993, along the east–west axis of the Straits of Johore between Singapore and Malaysia compared to other years (Wood et al., 1997). Heavy metals and metallic chemical elements (such as hydrogen, lithium,sodium, potassium and rubidium), highly dense and toxic, non-biodegradable substances are transported into marine ecological environment through storm runoff, and subsequently result in bioaccu- mulation in aquatic living organisms over a long period, dangerously af- fecting human health via consumption of food from a variety of aquatic life forms (Irwandi and Farida, 2009; Nazli and Hashim, 2010). Agricul- tural sector is another endocrine contributor of heavy metals in the en- vironment, sourced from fertilizers, pesticides and herbicides. Research in marine environmental system relating to ecotoxicology stated that mercury, cadmium, copper and zinc are the most dangerous heavy metals in the environment (Golovanova, 2008). Studies on identifica- tion and apportionment of heavy metals in the environment have been conducted worldwide. One example is the study on the accumula- tion of mercury, chromium, lead, arsenic and cadmium in European Marine Pollution Bulletin xxx (2016) xxx–xxx ⁎ Corresponding author. E-mail address: ekhwan@unisza.edu.my (M.E. Toriman). MPB-07235; No of Pages 9 http://dx.doi.org/10.1016/j.marpolbul.2015.10.019 0025-326X/© 2016 Elsevier Ltd. All rights reserved. Contents lists available at ScienceDirect Marine Pollution Bulletin journal homepage: www.elsevier.com/locate/marpolbul Please cite this article as: Ismail, A., et al., Spatial assessment and source identification of heavy metals pollution in surface water using several chemometric techniques, Marine Pollution Bulletin (2016), http://dx.doi.org/10.1016/j.marpolbul.2015.10.019