  Using the two-body interactions obtained from a chiral constituent quark
model we study all $\Lambda NN$ and $\Sigma NN$ states with I=0,1,2 and
J=1/2,3/2 at threshold, taking into account all three-body configurations with
S and D wave components. We constrain further the limits for the $\Lambda N$
spin-triplet scattering length a_{1/2,1}. Using the hypertriton binding energy
we find a narrow interval for the possible values of the $\Lambda N$
spin-singlet scattering length a_{1/2,0}. We found that the $\Sigma NN$ system
has a quasibound state in the (I,J) = (1,1/2) channel very near threshold with
a width of about 2.1 MeV.
