Еколого-гігієнична оцінка гостої токсичності води поверхневих водойм Українського Придунав’я за результатами біотестування

Abstract

Supervising international legal document on protection superficial, and also transit, coastal and underground waters is the Water frame directive (WFD), accepted by the European Parliament and the Council of Europe on October, 23rd, 2000. WFD it is obligatory for performance in the EU countries and it is desirable for the countriesneighbours, including for Ukraine. Instruction requirements extend to Ukraine in connection with presence of the general transboundary river pools, for example the river Danube which need performance of eurointegration obligations on their protection. WFD provides improvement of an ecological condition of water objects of delta of Danube to a condition “well” till the end of 2015 According to requirements WFD, generalisation of the received biotest results on the unified five-ball scale which gives the characteristic of an ecological condition of water objects (exelent, well, perfectly well, badly, very badly) is provided. This scale is approved at an ecological estimation of water of delta of Danube. Objective: to evaluate the results of ecological – hygienic assessment of acute toxicity of water surface reservoirs of Ukrainian Danube Region by the data of biological testing. Material and methods. The material is the aqueous samples of surface water bodies from Ukrainian Danube Region. The samples were taken on July 23 – 24, 2014. Place of sampling: the Danube ( Reni, Izmail, Kilia, Vilkovo) (samples 1-4); Lake Cahul (5); Lake Ialpug (6. 7); Lake Katlabuh (8, 9); Lake Kitay (10, 11); the Ialpug (12); the Karasulak (13); the Enic (14); irrigation canal the Danube – Lake Sasyk (15). We used the international standard for setting of acute toxicity using early stages of nauplial stages of Thamnocephalus platyurus (Crustacea, Anostraca). Ecological condition was evaluated according to the requirements of the EU Water Framework Directive 2000/60 / EC (WFD). Results and discussion. Exposure of early nauplial stages of T. platyurus in the water samples under analysis led to reduced survival in a number of samples, up to the absolute mortality. Water samples collected in the Danube (Reni, Izmail, Vylkove; 1, 2, 4), lakes Cahul (5) and Ialpug (6, 7), an irrigation canal the Danube – Lake Sasyk (15) showed an “excellent” class. Environmental class “good” is marked for the water of the Danube selected in Kealia (3). State of Lake Katlabuh (8, 9) water is evaluated as “good” and “satisfactory” (mortality of test -objects was at the level of 15 – 40 %, which corresponds to the low level of integrated toxicity). It should be noted that the water of the Lake Kitay is referred to the “excellent” (10) and “bad” (11) environmental classes. All samples (12-14) water of small rivers Ialpug, Karasulak, Enic flowing into the lake, were very toxic (environmental class “very bad”). Conclusions. Taking into account the persistent nature of the pollution of surface waters of Ukrainian Danube Region we suggested that there is a need for continued monitoring of acute aquatic toxicity of these objects, especially lakes and rivers, by bioassay methods.

Мета дослідження - еколого-гігіенічна оцінка гостої токсичності води поверхневих водойм Українського Придунав’я за результатами біотестування. Матеріалом слугували зразки води поверхневих водойм Українського Придунав’я, які відбирали 23,24 липня 2014 р.