Department of Environmental Science and Analytical Chemistry, Stockholm University, Stockholm, Sweden.
Department of Ecology, Environment and Plant Science, Stockholm University, Stockholm, Sweden.
Sci Rep. 2019 Jul 18;9(1):10406. doi: 10.1038/s41598-019-46815-3.
The evidence regarding BMAA occurrence in the Baltic Sea is contradictory, with benthic sources appearing to be more important than pelagic ones. The latter is counterintuitive considering that the identified sources of this compound in the food webs are pelagic primary producers, such as diatoms, dinoflagellates, and cyanobacteria. To elucidate BMAA distribution, we analyzed BMAA in the pelagic and benthic food webs in the Northern Baltic Proper. As potential sources, phytoplankton communities were used. Pelagic food chain was represented by zooplankton, mysids and zooplanktivorous fish, whereas benthic invertebrates and benthivorous fish comprised the benthic chain. The trophic structure of the system was confirmed by stable isotope analysis. Contrary to the reported ubiquitous occurrence of BMAA in the Baltic food webs, only phytoplankton, zooplankton and mysids tested positive, whereas no measurable levels of this compound occurred in the benthic invertebrates and any of the tested fish species. These findings do not support the widely assumed occurrence and transfer of BMAA to the top consumers in the Baltic food webs. More controlled experiments and field observations are needed to understand the transfer and possible transformation of BMAA in the food web under various environmental settings.
关于波罗的海 BMAA 存在的证据相互矛盾，底栖来源似乎比浮游来源更为重要。考虑到这种化合物在食物网中的已知来源是浮游初级生产者，如硅藻、甲藻和蓝藻，这是反直觉的。为了阐明 BMAA 的分布，我们分析了波罗的海北部的浮游和底栖食物网中的 BMAA。浮游植物群落被用作潜在的来源。浮游食物链由浮游动物、糠虾和浮游动物鱼类组成，而底栖无脊椎动物和底栖食鱼动物组成了底栖链。系统的营养结构通过稳定同位素分析得到证实。与报道的 BMAA 在波罗的海食物网中普遍存在的情况相反，只有浮游植物、浮游动物和糠虾呈阳性，而底栖无脊椎动物和任何测试的鱼类都没有可测量水平的这种化合物。这些发现不支持 BMAA 在波罗的海食物网中广泛存在并转移到顶级消费者的假设。需要进行更多的控制实验和现场观察，以了解在各种环境条件下，BMAA 在食物网中的转移和可能的转化。
