北纬沿海地区广泛报道的陆地溶解有机物(terrDOM)增加(“沿海变暗”)可能会影响受影响系统中的污染物动态。一个潜在的影响是基于分子较大的terrDOM与海洋DOM(marDOM)相比的化学吸附过程的差异,这导致亲脂性污染物与terrDOM的乳化增加。过滤喂食器每天过滤大量的水和DOM,因此通过呼吸和喂食活动直接暴露于相关的污染物。因此,暴露于terrDOM的增加可能会导致滤食中脂溶性污染物的生物积累增加。为了评估DOM对滤嘴中生物累积的影响,我们暴露了基于粘液的过滤器喂养海鞘Cionatestinalis(以前称为CionatestinalisB型),亲脂性兽药四氟苯并隆(logKOW:5.39)与四种DOM治疗相结合:TerrDOM,MarDOM,两者的混合称为mixDOM,和没有DOM添加的海水。暴露持续了15天,此后,所有DOM处理中的个体都显示出比海水对照中的个体更高的四氟苯隆生物累积趋势。然而,后验分布有相当大的重叠。违背我们的期望,火星导致了最高的生物积累因子(BAF),其次是mixDOM,除海水外,地形导致最低的BAF(动态BAFL/kg中位数,2.5%-97.5%百分位数marDOM94,74-118;mixDOM82,63-104;terrDOM79;61-99;海水61,44-79)。根据欧盟REACH法规(BAF<2000L/kg),所有BAF均低于关注水平,因此,在检查的背景下,可能没有环境问题。然而,结果表明,DOM可以作为膳食载体;因此,污染物的不同组合,DOM,和滤食生物应进一步测试。
The widely reported increase of terrestrial dissolved organic matter (terrDOM) in northern latitude coastal areas (\"coastal darkening\") can impact contaminant dynamics in affected systems. One potential impact is based on differences in chemical adsorption processes of the molecularly larger terrDOM compared to marine DOM (marDOM) that leads to increased emulsification of lipophilic contaminants with terrDOM. Filter feeders filter large amounts of water and DOM daily and thus are directly exposed to associated contaminants through both respiration and feeding activity. Thus, increased exposure to terrDOM could potentially lead to an increase in bioaccumulation of lipid soluble contaminants in filter feeders. To assess the effect of DOM on bioaccumulation in filter feeders, we exposed the mucous based filter feeding ascidian Ciona intestinalis (formerly known as Ciona intestinalis Type B), to the lipophilic veterinary drug teflubenzuron (log KOW: 5.39) in combination with four DOM treatments: TerrDOM, marDOM, a mix of the two called mixDOM, and seawater without DOM addition. The exposure lasted for 15 days, after which the individuals in all DOM treatments showed a trend towards higher bioaccumulation of Teflubenzuron than those in the seawater control. However, there was considerable overlap in posterior distributions. Against our expectations, marDOM resulted in the highest bioaccumulation factor (BAF), followed by mixDOM, with terrDOM resulting in the lowest BAF except for seawater (kinetic BAF L/kg median, 2.5 %-97.5 % percentile marDOM 94, 74-118; mixDOM 82, 63-104; terrDOM 79; 61-99; seawater 61, 44-79). All BAFs were below the level of concern according to the EU REACH regulation (BAF < 2000 L / kg) and, therefore, likely not environmentally problematic in the examined context. However, the results show that DOM can act as a dietary vector; thus, different combinations of contaminants, DOM, and filter feeding organisms should be tested further.