Plastic does not rot. It weathers. Sunlight, waves, heat and friction grind every bottle, bag, rope and fleece into fragments that are too small to see and too light to settle. Once the pieces are that small there is no fence between the environment and you : they ride in on what you eat, what you drink and the air you breathe.
This article follows the routes in, then walks through the house room by room to show where it is coming from. The next article follows the plastic back to where it came from.
Microplastics are pieces smaller than 5 millimetres, down to about a thousandth of a millimetre. Nanoplastics are smaller again, and small enough to pass through the wall of the gut and the lung. The smaller the particle, the further into the body it can travel.
Anything that lived in the sea has been filtering plastic out of the water, and shellfish, eaten whole, carry the most. Sea salt is evaporated sea water. Crops grow in soil that has plastic in it. Then the food is wrapped, tinned, bagged and cut on plastic before it reaches your mouth.
Bottled water generally carries more plastic than tap water, because the bottle and the cap shed into the water they hold. Tap water carries it too, at lower levels, because treatment does not remove all of it. Anything hot in a plastic or plastic-lined container releases more than anything cold.
Indoors, most of the plastic in the air is fibre from clothing, carpet, curtains and furniture made of polyester, nylon and acrylic, and house dust is largely made of it. Outdoors, the biggest single source is tyres, which wear down to nothing over their life and leave it on the road and in the air beside it.
Intact skin stops most particles. The concern is what is deliberately put on it, and what is deliberately put into the nose, eyes and lungs by sprays, drops and inhalers. Microbeads have been banned in New Zealand, but plastic in other forms is still common in personal care products.
The general rule : plastic sheds when it is rubbed, heated, flexed or old. Look around each room for the things that get one of those every day.
In the Kitchen
In the Bathroom
In the House
In the Bedroom
What you wear
Outside
Medical
There is no diet, no water source and no room that is free of plastic. The routes in are eating, drinking and breathing, and the largest contributors are seafood, bottled water, synthetic fabrics and tyre dust. Heat, friction and age make everything shed faster. You can reduce your intake, but you cannot avoid it, because it is already everywhere. Where it came from is the subject of the next article.