<p>Sentence 1:<br /> The presence of existing contaminants decreases bioavailability through hetero-aggregation, sorption, and/or complexation upon <strong>an</strong> interaction with MNPs. Contaminants also influence the fate and transport of MNPs <strong>and exhibit their synergistic toxic effects that contribute to the extent of the toxicity.</strong><br /> <br /> Phrase 1:Future research <strong>is needed</strong> on <strong>the</strong> toxicity modeling assessments <strong>of</strong> heterogeneous systems.</p>
<p><br /> To check:<br /> <br /> .....an update on the latest development....<br /> <strong>(&ldquo;an&rdquo; is correct)</strong></p>