PULP MILLS (JUDGMENT) 99 the record does not substantiate the claims made by Argentina on this matter. (v) Dioxins and furans 258. Argentina has alleged that while the concentration of dioxins and furans in surface sediments is generally very low, data from its studies demonstrated an increasing trend compared to data compiled before the Orion (Botnia) mill commenced operations. Argentina does not claim a violation of standards, but relies on a sample of sábalo fish tested by its monitoring team, which showed that one fish presented elevated levels of dioxins and furans which, according to Argentina, pointed to a rise in the incidence of dioxins and furans in the river after the commissioning of the Orion (Botnia) mill. Uruguay contests this claim, arguing that such elevated levels cannot be linked to the operation of the Orion (Botnia) mill, given the presence of so many other industries operating along the River Uruguay and in neighbouring Nandubaysal Bay, and the highly migratory nature of the sábalo species which was tested. In addition, Uruguay advances that its testing of the effluent coming from the Orion (Botnia) mill demonstrate that no dioxins and furans could have been introduced into the mill effluent, as the levels detected in the effluent were not measurably higher than the baseline levels in the River Uruguay. 259. The Court considers that there is no clear evidence to link the increase in the presence of dioxins and furans in the river to the operation of the Orion (Botnia) mill. (d) Effects on biodiversity 260. Argentina asserts that Uruguay “has failed to take all measures to protect and preserve the biological diversity of the River Uruguay and the areas affected by it”. According to Argentina, the treaty obligation “to protect and preserve the aquatic environment” comprises an obligation to protect the biological diversity including “habitats as well as species of flora and fauna”. By virtue of the “referral clause” in Article 41 (a), Argentina argues that the 1975 Statute requires Uruguay, in respect of activities undertaken in the river and areas affected by it, to comply with the obligations deriving from the CITES Convention, the Biodiversity Convention and the Ramsar Convention. Argentina maintains that through its monitoring programme abnormal effects were detected in aquatic organisms — such as malformation of rotifers and loss of fat by clams — and the biomagnification of persistent pollutants such as dioxins and furans was detected in detritus feeding fish (such as the sábalo fish). Argentina also contends that the operation of the mill poses a threat, under conditions of reverse flow, to the Esteros de Farrapos site, situated “in the lower section of the River . . . downstream from 89