When people typically talk about non-renewable resources, or about sustainability and preservation, the discussion often immediately jumps to oil. This makes a lot of sense - after all, oil is a very important resource, used for a wide variety of purposes from transportation to the creation of plastics, and because of that we’re using it up at an incredibly fast pace.

However, because oil is on the forefront of everybody’s minds, it tends to steal the spotlight from other resources we’re running out of. Most people would be hard pressed to name a non-renewable resource that isn’t a fossil fuel of some kind, but many of them are just as vital to our modern society as oil, if not more so.

For example, Helium. Helium is the second most common element in the entire universe, with massive clouds of it spanning the enormous space between star systems. It makes up one fourth of the total amount of mass in existence, but it’s rapidly running out in one very specific location: Earth.

Helium is very useful for an abundance of uses, from cryogenics to arc welding, from MRI scanners to silicon manufacturing and, of course, balloons at birthday parties. But because of its abundance of uses, our reserves are rapidly vanishing. It was recently estimated that America’s largest reserve of Helium, the Amarillo Gas Fields, only has enough remaining helium to last until 2020, at the very latest.

Thankfully, researches recently discovered a significantly sized reservoir of Helium in Tanzania, large enough to supply 1.2 million MRI scanners. But even this reservoir of Helium is finite, and can be expected to run dry in the future - unless we’re able to harvest helium directly from space nebulae sometime in the near future, we may be looking at a serious shortage soon.

And then there’s uranium, which isn’t just used for bombs and weaponry, or even just for power plants. It’s also used extensively in medicine. Medical isotopes are special varieties of radioactive substances, almost all created using Uranium, and they’re used in hospitals around the world for everything from full body scans (to detect cancer) and irradiation (to fight cancer).

While Uranium isn’t being used at nearly the same rate as oil or other natural gases (mostly because one kilogram of U-235 produces as much energy as 2,700 tons of coal), we’re still using it up much faster than we’re able to produce it. In 2012, it was estimated that the United States had access to enough Uranium to sustain its current rate of usage for 81 more years - which sounds like a long time, but that’s only a generation or two away.

We’ve already had a taste of what that would be like: in 2007, the Chalk River Laboratory in Ontario, Canada shut down for routine maintenance. It was only non-operational for a single month, but that was still enough to cause worldwide panic. It turns out that Chalk River provides 75% of the world’s medical isotopes, and shutting it down for a single month caused a worldwide shortage, putting millions of lives at risk.

And possibly most important of all is Phosphorus. Phosphorus is a vital nutrient for all life on the planet. Plants and animals of all kind require a daily intake of phosphorus to continue to live - and there’s no substitute, or way to synthesize it. That normally isn’t much of a problem. Like water, phosphorus moves through the ecosystem naturally, in a cycle, ensuring that while the amount of phosphorous in the system doesn’t often increase, it also almost never decreases.

However, humans don’t exactly like to play by natural rules. For the last century or so, we’ve been using massive amounts of phosphorus-based fertilizer, breaking the natural phosphorous cycle. Sure, it provides us with the massive amount of food we need to sustain our ludicrously huge world population of 8 billion, but it’s not sustainable.

Scientists estimate that if we don’t find some way to recycle phosphorus, the same way nature does it, we may hit peak phosphorus as soon as 35 years from now. And if the price of phosphorus goes up, the price of food will go up in tandem; if phosphorus runs out completely, we’ll just be out of luck. Without a reliable source of fertilizer, international food production would plummet, and it’s possible that millions could starve.

Our current usage of resource simply isn’t sustainable. The fact of the matter is that there’s a finite amount of almost every resource on our little planet, and unless we can figure out how to make that amount last indefinitely, through recycling or renewable alternatives, then human society as we know it won’t last either.