新菸鹼類農藥在台灣與日本茶葉中殘留之比較

Abstract

茶是世界上消費量第二大的飲料。雖然日本以其綠茶而聞名，台灣也有享譽全球的茶，如烏龍茶、紅茶、和高山茶。隨著飲茶的普及，茶葉在食品安全的議題也逐漸被重視。過去的研究顯示，茶葉在食品安全的議題也逐漸被重視；飲茶的潛在風險逐漸增加。在台灣，新菸鹼類已成為茶葉種植中最重要的殺蟲劑之一。但是，我們對茶葉中的新菸鹼類農藥殘留物了解甚少。新菸鹼類是一種系統性的殺蟲劑，已知對環境有不利的影響，並導致蜜蜂不育以及土壤和水污染。利用液相層析質譜儀（LC / MS-MS）來分析台灣產量排名前十二的鄉鎮所產之茶葉，來評估新菸鹼類殘留物及其是否有代謝產物殘留的可能性。並使用日本、歐盟、和中國的最大殘留標準（MRL）與之前日本茶葉殘留的研究（n = 39）進行比較。此研究結果表明，台灣樣本檢測到的新菸鹼類頻率較低，而代謝物殘留值相近於日本茶葉樣本。雖然在台灣茶樣品中未檢出賽果培，但檢出賽果培的代謝產物N-dc-dh-thiacloprid，可能具有新菸鹼類代謝產物殘留的隱患。台灣和日本的茶葉樣品都沒有超出該國所定的最大殘留量標準，但兩國所檢出之亞滅培及益達胺殘留量皆不符合歐盟標準。此研究反映各國最大農藥殘留料標準不同，可能在茶葉進出口上有所影響，新菸鹼類代謝產物在未來的研究中也應被重視。

Tea is the second most consumed beverage in the world. While Japan is famous for its green tea, Taiwan has many varieties, such as oolong, black tea, and mountain teas, which are also world-renowned. As the popularity of tea increases, food safety has been considered. Studies have indicated that there is a growing concern of pesticide residue in food and insecticides residue in tea. In Taiwan, neonicotinoids have become one of the most significant insecticides used in tea cultivation. Neonicotinoid is a major insecticide known to have adverse environmental effects and have contributed to infertility in bees as well as soil and water pollution. However, little is known of neonicotinoid residues in tea. The aim of this study is to evaluate the possibility of neonicotinoids and their metabolites residues remaining in tea. 12 tea samples collected from the highest tea producing townships in Taiwan were analyzed by liquid chromatography-mass spectroscopy (LC/MS-MS). The results using maximum residue level (MRL) standards from Taiwan, Japan, the European Union, and China were compared with the previous study of Japanese tea (n=39). Our findings show that Taiwanese samples have a lower frequency of neonicotinoids while the median level of metabolites is higher than that of Japanese samples. Although thiacloprid was not detected in Taiwanese tea samples, its metabolite N-descyano-dehydro-thiacloprid was expressed, suggesting a hidden risk of neonicotinoids in tea. The levels of neonicotinoids in both Taiwanese and Japanese tea samples do not exceed their domestic MRL standards, whereas the levels of acetamiprid and imidacloprid do not meet the European Union standard. This study concludes that different residue standards among countries may affect export and import of tea and that metabolites residue in tea leaves should be a concern in a further study.