3. Filter your water.
Every community is different, but nearly every municipality adds something to their water. What exactly? I can't speak to that. You'll need to contact your water supplier and discuss with them the additives in the water and then do research on each one.
Ugh, more research???
Yeah, sorry about that. A little bit of Googling goes a long way though. In the meantime, add a filter to your water. There are a lot of different types - some that just filter a few things, and some that are able to filter everything. Of course, the latter are way more expensive.
4. Flush 'em out.
Alright, here's where things get tricky. Some websites will tell you that you need to eat salt and lemon juice and maple syrup or something. That's all BS. Don't ever believe some magical cleanse remedy that includes chugging olive oil and salt. They don't work.
If you'd like to immediately begin to undo the damage, it's inexpensive and easy. The first step is to drink water. A lot of it. There's a lot of debate about how much water a human being needs to drink in order to be healthy.
Some argue that it's not much, some argue that it's upwards of two gallons of water each day. My personal rule of thumb is halve your body weight and drink that many ounces of water a day. So If you're 120 pounds, you'll want to drink 60 ounces of water each day.
Once you've started drinking adequate amounts of water, you'll notice your urination tick up a little bit. If you make this a habit and stay hydrated, that'll subside as your body gets used to it.
Now, start eating whole sources of fiber. Fruits, vegetables, chia seeds, hemp seeds, flax powder, oatmeal; anything with lots of fiber. This will help your intestines stay healthy and will improve your intestinal flora.
That's really all it takes to start flushing toxins. No magical elixirs, just water and good food.