( ( Reported toxicity ) ( ( is ( very low ) ) . ) )
(ROOT (S (NP (JJ Reported) (NN toxicity)) (VP (VBZ is) (ADJP (RB very) (JJ low))) (. .)))
Reported toxicity is very low.
(ROOT (S (NP (NP (DT The) (JJ main) (NN advantage)) (PP (IN of) (NP (NN urea)))) (VP (VBZ is) (NP (PRP$ its) (ADJP (RB very) (JJ low)) (NN toxicity))) (. .)))