This is a controversial topic, here you will find a lot of the science and reports about 1080 in water supplies...make your own informed decisions
From TBfree: "No withholding period is necessary for fruit, vegetables or animals. However, as a precaution, residents who have concerns for drinking water may choose to disconnect their water supply intakes for 24 hours after an aerial application. Other mitigation measures can be agreed and arranged such as establishing exclusion areas around water intakes and water testing to confirm the absence of contamination. There is no risk but to make people doubly comfortable, they can disconnect their water until we receive the results of water tests."