JOURNAL OF OIL PALM RESEARCH 18 (DECEMBER 2006) 288 Journal of Oil Palm Research Vol. 18 December 2006 p. 288-295 SAFETY ASSESSMENT OF PALM KERNEL OIL, PALM KERNEL STEARIN AND PALM KERNEL OLEIN IN MARINE ENVIRONMENT RAZMAH GHAZALI*; MOHD JAAFFAR AHMAD*; TANG THIN SUE*; MOHTAR YUSOF* and SALMIAH AHMAD* Keywords: palm kernel oil, palm kernel stearin, palm kernel olein, Acartia tonsa, Skeletonema costatum. Date received: 13 April 2006; Sent for revision: 23 April 2006; Received in final form: 16 May 2006; Accepted: 1 August 2006. ABSTRACT The acute toxicity of water accommodated fraction (WAF) of crude palm kernel oil (CPKO), crude palm kernel stearin (CPKST) and crude palm kernel olein (CPKOL) to Acartia tonsa (a marine copepod) and Skeletonema costatum (a chain forming marine algae) was determined at three loading rates: 10, 100 and 1000 mg litre -1 . WAF methodology was used for the toxicity tests as these palm products are poorly water- soluble. Measurement of the total carbon (TC) of the test medium before the start of the tests confirmed that there were low levels of solubilized material in the WAFs. The mean concentrations of TC in 1000 mg litre -1 WAFs prepared from palm kernel oil, palm kernel stearin and palm kernel olein were 4.5, 1.0 and 5.2 mg litre -1 , respectively. All the palm products tested were not toxic to A. tonsa. Palm kernel oil and palm kernel olein were harmless to S. costatum at a loading rate of 10 mg litre -1 . They were slightly toxic at 100 mg litre -1 and toxic at 1000 mg litre -1 . Palm kernel stearin was harmless to S. costatum at a loading rate of 100 mg litre -1 and only slightly toxic at 1000 mg litre -1 . INTRODUCTION There is general consensus that vegetable oil is generally safe for consumption as food. Large volumes of vegetable oils are shipped throughout the world, subject to various kinds of handling. There may well be spillage, in the worst case scenario, an accident with detrimental effect on the environment. Compounds are classified as pollutants if they cause a detrimental biological effect. This suggests that all compounds, whether considered pollutants or not, can become pollutants if present in a sufficiently large volume, such as those happens in a major spillage. Palm kernel oil is obtained from the kernel of the oil palm fruit. In its crude form, it is yellowish in colour and is easily bleached to a lighter colour suitable for both edible and inedible applications. The oil has a narrow melting range of 25C-28C and a much sharper solid fat content profile (Siew, 2004). The dominant fatty acid is lauric acid, constituting 46% to 51% of it. Fractionation of palm kernel oil gives a liquid (olein) and solid (stearin) fractions. The longer chain (≥C12) saturated acids occur in the stearin while the short chain (C6-C10) and unsaturated acids in the olein. Palm kernel stearin is the product most suitable for making cocoa-butter substitutes. It can be used directly or improved by hydrogenation. Palm kernel olein, on the other hand, is used in imitation dairy products or hydrogenated for confectionery. Palm kernel oils (PKO) are transported in very large volumes by sea around the world. Malaysia exported 850 649 t of PKO in 2005. The major buyers were the USA, which took 198 093 t (23% of Malaysian exports), European Union (EU) 169 769 t (20%), Japan 61 060 t (7.2%), China 48 050 t (5.6%) and Turkey 40 437 t (MPOB, 2006). The environmental toxicity of crude palm kernel oil (CPKO), crude palm kernel stearin (CPKST) and * Malaysian Palm Oil Board, P. O. Box 10620, 50720 Kuala Lumpur, Malaysia. E-mail: razmah@mpob.gov.my