Avobenzone is the only chemical UV-protection component with a broad spectrum coverage. It can help to block both UVA I and UVA II rays. It's safe and it is allowed to use at a 3% concentration in the USA and a 5% concentration in the EU countries.
There is one problem: avobenzone loses efficiency when exposed to the sun. If you are outside, it loses 36% of its ability to block UV rays an hour after application. That's why it's recommended to reapply sunscreen every 2 hours.
Octinoxate is an effective sun protector that absorbs UV-B rays mostly. That means it can help to protect the skin from burns and from cancer. It’s also a solvent for other sunscreen components. This helps manufacturers to make products less oily.
Water is a great solvent. It’s neutral and doesn’t provide any strong positive or negative effects. It just helps components to mix better and to transport active components.
