Are functions in libmwblas and libmwlapack thread safe?

I saw that Matlab exposes BLAS/LAPACK functions through libmwblas and libmwlapack. I am calling these functions from a mex function. I would like to know if the functions in these libraries are thread safe, so OK to call from inside an OpenMP parallel region (I know that matlab mex...() / mx...() functions are not).