To maintain good liver health and detox gradually and naturally, include fiber rich fruits and vegetables in your diet to help eliminate toxins that the liver breaks down. Include Sulfur-rich foods (onions, garlic, broccoli, kale, collard greens, Brussels sprouts, etc.) in your diet that are known to help your liver detoxify environmental toxins, including prescription drugs and pesticides. While you eliminate toxins work towards putting them into your system in the first place by avoiding foods (alcohol, processed foods, carbonated beverages, fried foods, trans fats, etc.) that increase the toxic load on your liver.
There is very little you can do about your external environment, but using a good quality RO water filter and air purifier at home should reduce the toxins the liver has to fight on a daily basis. Pure water is a great cleanser so keep your body and liver hydrated to aid smooth movement of toxins out of the system. Keep up your activity levels to expel toxins through sweat.
Ayurveda advocates a cleanse twice in a year (during specific seasons) and based on your prakriti that renews and resets the liver to fight the ever increasing battle against toxins.