Leaf Burning has more effects than you think

Leaf Burning has more effects than you think


Autumn is here, the leaves are falling and already an alarming number of residential bonfires are being set. Choking on an inconsiderate neighbour’s leaf smoke is more than just an irritation: it can pose serious health risks. The open burning of leaves produces particulate matter and hydrocarbons (similar to those found in tobacco smoke), which contain a number of toxic, irritant, and carcinogenic (cancer-causing) compounds, as well as carbon monoxide.


1. The particulate matter consists of tiny particles (<10 microns) that can reach the deepest regions of the lung and remain there for months. Particles less than 2.5 microns are the cause for most concern as these can penetrate blood vessels and lead to heart attacks and strokes. Breathing particulate matter can increase the chances of respiratory infection, reduce the volume of air inhaled and impair the lungs’ ability to use that air. Particulate matter can also trigger asthma attacks.


2. Because leaves are often moist and burn without proper air circulation (those insidious smouldering fires that last all night!), they often burn poorly, producing high levels of hydrocarbons. Hydrocarbons are chemicals, e.g. aldehydes and ketones that can cause irritation of the eyes, nose, throat, and lungs, and can cause cancer in the long term.


3. Carbon monoxide is an invisible gas that results from incomplete combustion in burning leaf piles. Carbon monoxide is absorbed into the bloodstream through the lungs and combines with red blood cells. This reduces the amount of oxygen the red blood cells can absorb and supply to body tissues. Unborn children, newborn infants, smokers, the elderly, and persons with heart and chronic lung disease are the most susceptible to carbon monoxide.


Additionally, burning organic matter also releases carbon dioxide into the air which can contribute to global warming and climate change. Current CO2 levels in the world are 391 parts per million (ppm), a whopping 111ppm greater than pre-industrial levels of 280ppm! We need to take protecting our air quality seriously. I’m sure nobody wants to don respirators just to go outside as residents have to do in Beijing. Our children may well be faced with that prospect if we do not do something. There are 7 billion people that we share this planet with, and we each need to make sure we are not part of the problem. The eco-friendly alternative of disposing leaves is to make compost.

Composting is a simple process that involves placing yard trimmings and other organic materials such as vegetable peelings into a pile or bin.

Microorganisms gradually break down the yard trimmings. The process is speeded up by watering the compost heap and turning it occasionally to mix in oxygen. You can cover with plastic once watered to keep the moisture in.

Use the compost to enrich your soil – your plants will love it.

Also, don’t be afraid to educate your neighbours on the hazards of leaf burning. Awareness is needed.


Dr Lisa Marabini


Director, AWARE Trust

Cell: 0712 886650