Tetrodotoxin in Various Tissues of Yellow Puffer Fish, Xenopterus naritus (Richardson 1848) from Betong, Sarawak, Malaysia

Tetrodotoxin (TTX) content of the yellow puffer fish, Xenopterus naritus (Richardson 1848) collected from Kg. Manggut, Betong, Sarawak, Malaysia was studied from August 2011 to June 2012. A total sample of 276 fish (141 males, 135 females) with total lengths ranging from 12.5 to 31.0 cm and body weights from 38.9 to 711g were used in the study. The amount of TTX in different tissues (liver, skin, muscle, gonad and stomach) was analysed using liquid chromatography-mass spectrometry mass spectrometry (LC-MS/MS). Results showed that the concentrations of TTX in all tissues between the months were significantly different throughout the year (p 0.05). The highest mean of TTX was detected in the ovary (330 μg.g^-1), followed by the stomach (22.1 μg.g^-1), liver (17.8 μg.g^-1), skin (17.1 μg.g^-1), muscle (11.1 μg.g^-1) and testis (7.88 μg.g^-1). The highest amount of TTX was recorded in June 2012 in all the tissues. The highest mean gonadosomatic index (GSI) was recorded in August 2011. All the tissues in the present study contained TTX that exceeded the regulatory limit of 2 μg.g-1 (10 MU·g^-1) established as a safe level for human consumption by the Japan Food Hygiene Association (2005). The information gained from this study indicates the importance removing TTX to ensure the safe consumption of puffer fish.