Development of growth inhibition tests on species of the genus Myriophyllum L. 1754 (Saxifragales, Haloragaceae) for use in environmental risk assessment of herbicides and sediment quality control

Abstract

<p>&nbsp; &nbsp; Razvojem testova inhibicije rasta na vrstama&nbsp; roda&nbsp;<em> Myriophyllum&nbsp;</em> ispitan je<br />potencijal&nbsp; vrsta <em>Myriophyllum&nbsp; aquaticum</em>&nbsp; (Vell.) Verd.&nbsp; i&nbsp;<em> Myriophyllum spicatum</em>&nbsp; L. u<br />ekolo&scaron;koj proceni rizika&nbsp; od herbicida i kontrole kvaliteta sedimenta. Ispitana je<br />primenljivost&nbsp; kontaktnog testa toksičnosti sedimenta sa vrstom&nbsp; M. aquaticum&nbsp; u<br />retrospektivnoj&nbsp; proceni&nbsp; rizika&nbsp; sedimenta&nbsp; na uzorcima iz prirode&nbsp; &ndash;&nbsp; na sedimentu&nbsp; reka Tami&scaron;, Krivaja i Jegrička.&nbsp; Testom toksičnosti sedimenta obogaćenog atrazinom,<br />analiziran je i potencijal kontaktnog testa u preventivnoj proceni rizika od hemikalija<br />koje pokazuju afinitet vezivanja za sediment. Testovima inhibicije rasta <em>M. aquaticum</em><br />i&nbsp; <em>M. spicatum&nbsp;</em> u voda-sediment sistemu ispitana je osetljivost i mogućnost primene<br />metode u preventivnoj proceni rizika od herbicida i regulatora rasta.<br />&nbsp; &nbsp; Deo rezultata dobijenih u radu uključen je u zavr&scaron;ne izve&scaron;taje internacionalnih<br />testova interkalibracije metoda,&nbsp; a kao rezultat ovih aktivnosti usvojene su nove<br />standardne metode na ukorenjenim akvatičnim makrofitama ISO 16191/2013 i OECD 239/2014.<br />&nbsp; &nbsp; &nbsp; Na osnovu istraživanja, zaključeno je da je kontaktni test toksičnosti<br />sedimenta&nbsp; jednostavan i lak za izvođenje, kao i da je vrsta<em>&nbsp; M. aquaticum</em>&nbsp; u jedno-komponentnom sistemu (sediment)&nbsp; adekvatan test model. Rastom kontrolnih biljaka, niskom varijabilno&scaron;ću i visokom osetljivo&scaron;ću biolo&scaron;kih&nbsp; odgovora zadovoljen je kriterijum validnosti testa. Preporučeno je kori&scaron;ćenje dodatne kontrole&nbsp; u&nbsp; slučajevima kada postoje značajna odstupanja u strukturi između&nbsp; standardnog sintetičkog kontrolnog i&nbsp; testiranog prirodnog sedimenta.&nbsp; Kontaktnim&nbsp; testom toksičnosti sedimenta obogaćenog&nbsp; atrazinom&nbsp; pokazano je da se ovaj test&nbsp; može smatrati potencijalno dobrom metodom za pro&scaron;irenje ekolo&scaron;ke procene rizika od hemikalija koje pokazuju afinitet vezivanja za sediment.<br />&nbsp; &nbsp; Ispitivanjem potencijala&nbsp; testa&nbsp; inhibicije rasta vrsta roda&nbsp;<em> Myriophyllum</em>&nbsp; u voda-sediment sistemu&nbsp; utvrđeno je da su testovi&nbsp; izvodljivi u praksi, da pokazuju&nbsp; visoki stepen stabilnosti, statističku snagu i malu varijabilnost&nbsp; većine&nbsp; ispitivanih parametara rasta. Poređenjem testova sa vrstama&nbsp;<em> M. aquaticum</em>&nbsp; i&nbsp;<em> M. spicatum</em>, nije utvrđena značajna&nbsp; razlika u osetljivosti na odabrane herbicide.&nbsp; Osetljivost&nbsp; testova na vrstama roda&nbsp; <em>Myriophyllum</em>&nbsp; i standardnih&nbsp; Lemna&nbsp; testova je bila slična,&nbsp; osim u slučaju auksin simulatora gde su&nbsp; vrste roda <em>Myriophyllum</em>&nbsp; sp. bile osetljivije,&nbsp; &scaron;to&nbsp; ukazuje&nbsp; na njihovu primenljivost u proceni rizika od pesticida specifičnog mehanizma toksičnog dejstva.<br />&nbsp; &nbsp; Iako&nbsp; obe vrste roda&nbsp; <em>Myriophyllum</em>&nbsp; imaju&nbsp; prednosti i nedostatke&nbsp; kao test<br />organizmi,&nbsp; vrste se&nbsp; mogu&nbsp; smatrati reprezentativnim akvatičnim ukorenjenim<br />makrofitama i predstavljati&nbsp; adekvatne&nbsp; dopunske test vrste u vi&scaron;im nivoima ekolo&scaron;ke<br />procene rizika od herbicida i regulatora rasta.&nbsp; Takođe, vrsta <em>M. aquaticum&nbsp; </em>je pogodna za&nbsp; testiranje u&nbsp; različitim test sistemima,&nbsp; a samim tim&nbsp; ima i veći&nbsp; potencijal primene u preventivnoj, ali i retrospektivnoj ekolo&scaron;koj proceni rizika.</p>

<p>Growth inhibition tests on <em>Myriophyllum&nbsp; aquaticum</em>&nbsp; (Vell.) Verd.&nbsp; and <em>Myriophyllum spicatum</em>&nbsp; L.&nbsp; were conducted in order to assess their use in refined risk assessment&nbsp; of chemicals, as well as in&nbsp; sediment&nbsp; risk assessment.&nbsp; The applicability, stability and sensitivity of the&nbsp;<em> M.&nbsp; aquaticum&nbsp; </em>sediment contact test on natural sediments (from rivers Tami&scaron;, Krivaja and&nbsp; Jegrička) was assessed for use in retrospective ecological risk assessment (ERA). The potential use of the spiked sediment contact test in risk assessment&nbsp; of&nbsp; sediment bound chemicals was&nbsp; also investigated. The sensitivity and applicability of the growth inhibition tests on&nbsp;<em> M. aquaticum</em>&nbsp; and&nbsp; <em>Myriophyllum </em>spicatum&nbsp; in a water-sediment system was assessed for potential use in prospective ERA of plant protection products.</p><p>A part of the results of this study was included in the final report of the two&nbsp; international ring tests, which resulted with new standardised methods with rooted macrophytes:&nbsp; ISO 16191/2013 i&nbsp; OECD&nbsp; 239/2014. Tests on&nbsp; <em>Myriophyllum</em>&nbsp; species were compared to standard Lemna&nbsp; tests.&nbsp; Test substances in <em>M. aquaticum</em>&nbsp; and&nbsp; <em>Lemna minor&nbsp; L</em>. tests were 3,5 dichlorphenol, atrazine, isoproturon, trifluralin, 2,4 D and dicamba, while substances used in&nbsp;<em> M. spicatum&nbsp;</em> tests were atrazine, isoproturon and 2,4 D.</p><p>The sediment contact test proved to be simple and robust, while <em>M. aquaticum</em> can be considered as an adequate test model in a one-compartment (sediment) test. The validity criteria regarding control plant growth and variability was met. The use of an additional control is suggested when testing of sediments with considerably different properties of the standard synthetic control is taking place.&nbsp; The spiked sediment contact tests with atrazine showed that the method could be applied in prospective risk assessment of sediment bound chemicals.</p><p>The water-sediment growth inhibition test with&nbsp; <em>Myriophyllum</em>&nbsp; species proved to be applicable in practice, with high stability, statistical power and low variability of the majority of the growth parameters.<em>&nbsp; M. aquaticum&nbsp;</em> and&nbsp; M. spicatum&nbsp; didn&rsquo;t show major&nbsp; differences&nbsp; in sensitivity to tested substance.&nbsp; The sensitivity of&nbsp; <em>Myriophyllum</em> and&nbsp; Lemna&nbsp; tests was also similar, except to auxin simulators, where&nbsp; <em>Myriophyllum </em>species were considerably more sensitive, which makes them adequate&nbsp; candidates for use in risk assessment of chemicals with specific mode of action.</p><p>Even though both&nbsp; <em>Myriophyllum</em>&nbsp; species show advantages and disadvantages as test organisms, they can be regarded as representative rooted aquatic macrophyte species and additional test species in refined risk assessment of herbicides and growth regulators. &nbsp;Also,&nbsp; <em>M. aquaticum&nbsp; </em>can be tested in various test syytems, which makes this species &nbsp;applicable in prospective as well as retrospective ecological risk assessment.</p>