( ( ( A ( ( very low ) toxicity ) ) ( to ( ( birds and ) humans ) ) ) . )
(ROOT (NP (NP (NP (DT A) (ADJP (RB very) (JJ low)) (NN toxicity)) (PP (TO to) (NP (NNS birds) (CC and) (NNS humans)))) (. .)))
A very low toxicity to birds and humans.
(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))) (. .)))