There are currently 61 nuclear power plants operating in the US, containing 99 nuclear reactors. Most plants are located along the east coast, with the highest concentration between New Hampshire and Virginia. Nuclear plant meltdowns can be extremely dangerous, as seen at Fukushima in 2011 where up to 10,000 deaths are estimated from the three meltdowns and radioactive release. Radiation exposure can cause health effects like hair loss, cancer, and birth defects depending on the dose. While nuclear power provides around 19.5% of US electricity, the radioactive waste remains a challenge to store safely for thousands of years and nuclear accidents continue to be a risk that some argue is not worth the benefit of the energy.