What are the environmental risks of mycotoxins present in freshwater ecosystems within UK agricultural landscapes?

英国农业景观中淡水生态系统中存在的霉菌毒素有哪​​些环境风险？

• 批准号: 2119798
• 金额: --
• 依托单位: Plymouth University
• 依托单位国家: 英国
• 项目类别: Studentship
• 财政年份: 2016
• 资助国家: 英国
• 起止时间: 2016 至 无数据
• 项目状态: 已结题
• 来源: https://gtr.ukri.org/projects?ref=studentship-2119798
• 关键词: What; environmental; risks; mycotoxins; present

Mycotoxins are toxic secondary metabolites of fungi such as Aspergillus sp. and Fusarium sp. that grow on a wide variety of cereal crops. Fungal infestations in crops have increased in recent years due to the adoption of minimal tillage practices, decreased crop rotations and climate change. Exposure to mycotoxins has adverse impacts on the health of humans and wildlife following ingestion, inhalation or skin contact. United States government scientists very recently reported worryingly high concentrations of mycotoxins in streams used by livestock or as sources of human drinking water. Results of the 2014 US study suggest that both diffuse (e.g. release from fungi infected crops) and point (e.g. food processing plants) sources are important pathways for mycotoxin transport into freshwater ecosystems. Mycotoxins are therefore an important class of emerging contaminants and yet there is a clear lack of scientific data on their health impacts in aquatic organisms. Mycotoxins display a wide range of physico-chemical properties (with log Kow values from <1 to >7) and are often resistant to biodegradation. The main groups of mycotoxins including aflatoxins, beauvericin, trichothecenes and zearalenone. Some metabolites of mycotoxins cause endocrine disruption in mammals (for instance alpha-zearalanol (a-ZOL) and beta-zearalanol (b-ZOL) have oestrogenic activity similar to that of steroidal oestrogens and a-ZOL is commonly used in North America for growth promotion in cattle). However, there is a lack of data on the developmental and reproductive effects of most mycotoxins to fish and other aquatic organisms. In the future the increase in disease resistance problems with synthetic fungicides will likely lead to increased mycotoxin exposure and consequent health risks. Recent European regulation may also lead to significant reductions in fungicide availability for sustainable agriculture and horticulture unless the science is available to undertake a comparative risk assessment of mycotoxins and fungicides. It is essential to fill this critical knowledge gap in order to support sustainable crop production and make evidence-based decisions on the risks to wildlife of mycotoxin versus synthetic fungicides. This studentship will address the hypothesis that there are harmful levels of mycotoxins in freshwaters and biota within UK agricultural landscapes. The proposed work will (a) quantify mycotoxin concentrations in surface waters and invertebrates and (b) conduct laboratory studies to investigate their ecotoxicological impacts in fish and aquatic invertebrates. The field and laboratory data will be integrated to address for the first time the relative risks posed by mycotoxins detected in UK surface waters.

真菌毒素是曲霉等真菌的有毒次生代谢产物。和镰刀菌属(Fusarium sp.)它们生长在各种各样的谷类作物上。近年来，由于采用最少耕作措施、作物轮作减少和气候变化，作物中的真菌感染有所增加。在摄入、吸入或皮肤接触后，暴露于真菌毒素会对人类和野生动物的健康产生不利影响。美国政府的科学家最近报告说，在牲畜使用的溪流或作为人类饮用水来源的溪流中，真菌毒素浓度高得令人担忧。2014年美国的研究结果表明，扩散源(例如从受真菌感染的作物释放)和点源(例如食品加工厂)都是霉菌毒素进入淡水生态系统的重要途径。因此，霉菌毒素是一类重要的新兴污染物，但显然缺乏关于其对水生生物健康影响的科学数据。霉菌毒素表现出广泛的物理化学性质(logKow值从&lt；1到&gt；7)，并且通常对生物降解具有抵抗力。真菌毒素的主要类群包括黄曲霉毒素、白僵菌素、毛霉烯和玉米赤霉烯酮。真菌毒素的一些代谢物会扰乱哺乳动物的内分泌(例如，α-玉米赤霉醇(a-ZOL)和β-玉米赤霉醇(b-ZOL)具有与类固醇雌激素相似的雌激素活性，a-ZOL在北美通常用于促进牛的生长)。然而，缺乏关于大多数真菌毒素对鱼类和其他水生生物的发育和生殖影响的数据。在未来，合成杀菌剂的抗病问题的增加可能会导致真菌毒素暴露的增加，并随之而来的健康风险。欧洲最近的法规还可能导致可持续农业和园艺业的杀菌剂供应大幅减少，除非有科学依据对霉菌毒素和杀菌剂进行比较风险评估。必须填补这一关键的知识空白，以支持可持续的作物生产，并就霉菌毒素与合成杀菌剂对野生动物的风险作出循证决定。这项研究将解决这样一种假设，即英国农业景观中的淡水和生物群中存在有害水平的真菌毒素。拟议的工作将(A)量化地表水和无脊椎动物中的真菌毒素浓度，(B)进行实验室研究，以调查其对鱼类和水生无脊椎动物的生态毒理影响。现场和实验室数据将被整合，以首次解决在英国地表水中检测到的霉菌毒素构成的相对风险。