This appears to be Eastern Black Nightshade.  While all parts of the plant contain toxic compounds, primarily solanine, the plant does not transmit the toxin to garden produce growing nearby such as green bean plants.  Further, it will not poison your garden soil. However, it can pose a problem in that it competes with garden plants and can act as a host for various plant pests and diseases which may affect green beans.  The risk associated with Eastern Black Nightshade is from consuming the plant itself, particularly the unripe green berries and leaves.